✨ Added rust prettier plugin

frontend/package-lock.json

@@ -39,6 +39,7 @@
         "@codemirror/view": "^6.38.2",
         "@lezer/highlight": "^1.2.1",
         "@lezer/lr": "^1.4.2",
+        "@prettier/plugin-xml": "^3.4.2",
         "codemirror": "^6.0.2",
         "codemirror-lang-elixir": "^4.0.0",
         "colors-named": "^1.0.2",
@@ -46,6 +47,7 @@
         "franc-min": "^6.2.0",
         "hsl-matcher": "^1.2.4",
         "java-parser": "^3.0.1",
+        "jinx-rust": "^0.1.6",
         "jsox": "^1.2.123",
         "lezer": "^0.13.5",
         "linguist-languages": "^9.0.0",
@@ -54,6 +56,7 @@
         "pinia": "^3.0.3",
         "pinia-plugin-persistedstate": "^4.5.0",
         "prettier": "^3.6.2",
+        "prettier-plugin-rust": "^0.1.9",
         "remarkable": "^2.0.1",
         "sass": "^1.92.1",
         "sql-formatter": "^15.6.9",
@@ -1854,6 +1857,18 @@
         "url": "https://opencollective.com/popperjs"
       }
     },
+    "node_modules/@prettier/plugin-xml": {
+      "version": "3.4.2",
+      "resolved": "https://registry.npmmirror.com/@prettier/plugin-xml/-/plugin-xml-3.4.2.tgz",
+      "integrity": "sha512-/UyNlHfkuLXG6Ed85KB0WBF283xn2yavR+UtRibBRUcvEJId2DSLdGXwJ/cDa1X++SWDPzq3+GSFniHjkNy7yg==",
+      "license": "MIT",
+      "dependencies": {
+        "@xml-tools/parser": "^1.0.11"
+      },
+      "peerDependencies": {
+        "prettier": "^3.0.0"
+      }
+    },
     "node_modules/@rolldown/pluginutils": {
       "version": "1.0.0-beta.29",
       "resolved": "https://registry.npmmirror.com/@rolldown/pluginutils/-/pluginutils-1.0.0-beta.29.tgz",
@@ -2730,6 +2745,24 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@xml-tools/parser": {
+      "version": "1.0.11",
+      "resolved": "https://registry.npmmirror.com/@xml-tools/parser/-/parser-1.0.11.tgz",
+      "integrity": "sha512-aKqQ077XnR+oQtHJlrAflaZaL7qZsulWc/i/ZEooar5JiWj1eLt0+Wg28cpa+XLney107wXqneC+oG1IZvxkTA==",
+      "license": "Apache-2.0",
+      "dependencies": {
+        "chevrotain": "7.1.1"
+      }
+    },
+    "node_modules/@xml-tools/parser/node_modules/chevrotain": {
+      "version": "7.1.1",
+      "resolved": "https://registry.npmmirror.com/chevrotain/-/chevrotain-7.1.1.tgz",
+      "integrity": "sha512-wy3mC1x4ye+O+QkEinVJkPf5u2vsrDIYW9G7ZuwFl6v/Yu0LwUuT2POsb+NUWApebyxfkQq6+yDfRExbnI5rcw==",
+      "license": "Apache-2.0",
+      "dependencies": {
+        "regexp-to-ast": "0.5.0"
+      }
+    },
     "node_modules/acorn": {
       "version": "8.15.0",
       "resolved": "https://registry.npmmirror.com/acorn/-/acorn-8.15.0.tgz",
@@ -4821,6 +4854,12 @@
         "lodash": "4.17.21"
       }
     },
+    "node_modules/jinx-rust": {
+      "version": "0.1.6",
+      "resolved": "https://registry.npmmirror.com/jinx-rust/-/jinx-rust-0.1.6.tgz",
+      "integrity": "sha512-qP+wtQL1PrDDFwtPKhNGtjWOmijCrKdfUHWTV2G/ikxfjrh+cjdvkQTmny9RAsVF0jiui9m+F0INWu4cuRcZeQ==",
+      "license": "MIT"
+    },
     "node_modules/jiti": {
       "version": "2.4.2",
       "resolved": "https://registry.npmmirror.com/jiti/-/jiti-2.4.2.tgz",
@@ -5785,6 +5824,31 @@
         "url": "https://github.com/prettier/prettier?sponsor=1"
       }
     },
+    "node_modules/prettier-plugin-rust": {
+      "version": "0.1.9",
+      "resolved": "https://registry.npmmirror.com/prettier-plugin-rust/-/prettier-plugin-rust-0.1.9.tgz",
+      "integrity": "sha512-n1DTTJQaHMdnoG/+nKUvBm3EKsMVWsYES2UPCiOPiZdBrmuAO/pX++m7L3+Hz3uuhtddpH0HRKHB2F3jbtJBOQ==",
+      "license": "MIT",
+      "dependencies": {
+        "jinx-rust": "0.1.6",
+        "prettier": "^2.7.1"
+      }
+    },
+    "node_modules/prettier-plugin-rust/node_modules/prettier": {
+      "version": "2.8.8",
+      "resolved": "https://registry.npmmirror.com/prettier/-/prettier-2.8.8.tgz",
+      "integrity": "sha512-tdN8qQGvNjw4CHbY+XXk0JgCXn9QiF21a55rBe5LJAU+kDyC4WQn4+awm2Xfk2lQMk5fKup9XgzTZtGkjBdP9Q==",
+      "license": "MIT",
+      "bin": {
+        "prettier": "bin-prettier.js"
+      },
+      "engines": {
+        "node": ">=10.13.0"
+      },
+      "funding": {
+        "url": "https://github.com/prettier/prettier?sponsor=1"
+      }
+    },
     "node_modules/process": {
       "version": "0.11.10",
       "resolved": "https://registry.npmmirror.com/process/-/process-0.11.10.tgz",
@@ -5977,6 +6041,12 @@
         "url": "https://paulmillr.com/funding/"
       }
     },
+    "node_modules/regexp-to-ast": {
+      "version": "0.5.0",
+      "resolved": "https://registry.npmmirror.com/regexp-to-ast/-/regexp-to-ast-0.5.0.tgz",
+      "integrity": "sha512-tlbJqcMHnPKI9zSrystikWKwHkBqu2a/Sgw01h3zFjvYrMxEDYHzzoMZnUrbIfpTFEsoRnnviOXNCzFiSc54Qw==",
+      "license": "MIT"
+    },
     "node_modules/remarkable": {
       "version": "2.0.1",
       "resolved": "https://registry.npmmirror.com/remarkable/-/remarkable-2.0.1.tgz",

frontend/package.json

@@ -43,6 +43,7 @@
     "@codemirror/view": "^6.38.2",
     "@lezer/highlight": "^1.2.1",
     "@lezer/lr": "^1.4.2",
+    "@prettier/plugin-xml": "^3.4.2",
     "codemirror": "^6.0.2",
     "codemirror-lang-elixir": "^4.0.0",
     "colors-named": "^1.0.2",
@@ -50,6 +51,7 @@
     "franc-min": "^6.2.0",
     "hsl-matcher": "^1.2.4",
     "java-parser": "^3.0.1",
+    "jinx-rust": "^0.1.6",
     "jsox": "^1.2.123",
     "lezer": "^0.13.5",
     "linguist-languages": "^9.0.0",
@@ -58,6 +60,7 @@
     "pinia": "^3.0.3",
     "pinia-plugin-persistedstate": "^4.5.0",
     "prettier": "^3.6.2",
+    "prettier-plugin-rust": "^0.1.9",
     "remarkable": "^2.0.1",
     "sass": "^1.92.1",
     "sql-formatter": "^15.6.9",

frontend/src/utils/prettier/plugins/rust/format/comments.ts

@@ -0,0 +1,824 @@
+import { CommentOrDocComment, LocArray, Node, NodeType, NodeWithBodyOrCases } from "jinx-rust";
+import {
+	end,
+	getBodyOrCases,
+	getLastParameter,
+	hasOuterAttributes,
+	isInner,
+	is_Attribute,
+	is_AttributeOrDocComment,
+	is_BlockCommentKind,
+	is_BlockCommentNode,
+	is_Comment,
+	is_CommentOrDocComment,
+	is_ExpressionWithBodyOrCases,
+	is_ExternSpecifier,
+	is_FlowControlExpression,
+	is_FunctionDeclaration,
+	is_FunctionNode,
+	is_IfBlockExpression,
+	is_LineCommentKind,
+	is_LineCommentNode,
+	is_LocArray,
+	is_MacroRule,
+	is_NodeWithBodyOrCases,
+	is_ReassignmentNode,
+	is_StatementNode,
+	is_StructLiteralProperty,
+	is_StructLiteralPropertySpread,
+	nisAnyOf,
+	ownStart,
+	start,
+} from "jinx-rust/utils";
+import { is_CallExpression_or_CallLikeMacroInvocation } from "../transform";
+import { Narrow, assert, exit, iLast, last_of, maybe_last_of } from "../utils/common";
+import { is_MemberAccessLike, is_xVariableEqualishLike } from "./core";
+import {
+	AnyComment,
+	CustomOptions,
+	DCM,
+	Doc,
+	MutatedAttribute,
+	NodeWithComments,
+	PrettierCommentInfo,
+	breakParent,
+	cursor,
+	hardline,
+	indent,
+	join,
+	line,
+	lineSuffix,
+	literalline,
+} from "./external";
+import { assertPathAtNode, canAttachComment, getAllComments, getContext, getNode, getOptions, pathCallEach } from "./plugin";
+import { shouldPrintOuterAttributesAbove } from "./styling";
+
+function addCommentHelper(node: Node, comment: AnyComment, leading = false, trailing = false) {
+	__DEV__: assert(!handled(comment));
+	((node as NodeWithComments<Node>).comments ??= []).push(comment);
+	(comment.leading = leading), (comment.trailing = trailing), (comment.printed = false);
+}
+
+function addLeadingComment(node: Node, comment: AnyComment) {
+	addCommentHelper(node, comment, true);
+}
+function addDanglingComment(node: Node, comment: AnyComment, marker: DCM) {
+	addCommentHelper(node, comment);
+	comment.marker = marker;
+}
+function addTrailingComment(node: Node, comment: AnyComment) {
+	addCommentHelper(node, comment, false, true);
+}
+export function setPrettierIgnoreTarget(node: Node, comment: AnyComment) {
+	__DEV__: Narrow<Node & { prettierIgnore?: true }>(node), assert(isPrettierIgnoreComment(comment) || isPrettierIgnoreAttribute(comment));
+	comment.unignore = true;
+	node.prettierIgnore = true;
+}
+
+function hasComments<T extends Node>(node: T): node is NodeWithComments<T> {
+	return "comments" in node && node.comments.length > 0;
+}
+
+export function printDanglingComments(enclosingNode: Node, sameIndent: boolean, marker?: DCM) {
+	if (hasComments(enclosingNode)) {
+		const printed: Doc[] = [];
+		pathCallEach(enclosingNode, "comments", (comment) => {
+			if (isDangling(comment) && (!marker || comment.marker === marker)) {
+				printed.push(printComment(comment));
+			}
+		});
+		if (printed.length > 0) {
+			return sameIndent //
+				? join(hardline, printed)
+				: indent([hardline, join(hardline, printed)]);
+		}
+	}
+	return "";
+}
+
+export function needsHardlineAfterDanglingComment(node: Node) {
+	if (!hasComment(node)) return false;
+	const lastDanglingComment = maybe_last_of(getComments(node, CF.Dangling));
+	return lastDanglingComment && is_LineCommentNode(lastDanglingComment);
+}
+export function setDidPrintComment(comment: AnyComment) {
+	comment.printed = true;
+}
+
+function printComment(comment: AnyComment) {
+	__DEV__: assertPathAtNode("printComment", comment);
+	__DEV__: assert(handled(comment), `Assertion failed: Comment was not printed at ${comment.loc.url()}`, comment);
+	setDidPrintComment(comment);
+	return getContext().options.printer.printComment!(getContext().path as any, getOptions());
+}
+
+export function isPreviousLineEmpty(node: Node) {
+	let index = start(node) - 1;
+	index = skipSpaces(index, true) as number;
+	index = skipNewline(index, true) as number;
+	index = skipSpaces(index, true) as number;
+	return index !== skipNewline(index, true);
+}
+export function hasBreaklineBefore(node: Node) {
+	return hasNewline(start(node) - 1, true);
+}
+
+export function hasBreaklineAfter(node: Node) {
+	return hasNewline(end(node));
+}
+
+export function printCommentsSeparately(ignored?: Set<AnyComment>) {
+	const node = getNode();
+	__DEV__: Narrow<Node & { comments?: AnyComment[] }>(node);
+
+	const leading: Doc[] = [];
+	const trailing: Doc[] = [];
+	let hasTrailingLineComment = false;
+	let hadLeadingBlockComment = false;
+
+	if ("comments" in node) {
+		pathCallEach(node, "comments", (comment) => {
+			if (ignored?.has(comment)) {
+				return;
+			} else if (isLeading(comment)) {
+				leading.push(printLeadingComment(comment));
+			} else if (isTrailing(comment)) {
+				trailing.push(printTrailingComment(comment));
+			}
+		});
+	}
+
+	if (node === getOptions().cursorNode) {
+		leading.unshift(cursor);
+		trailing.push(cursor);
+	}
+
+	return (leading.length | trailing.length) > 0 ? { leading, trailing } : ({ leading: "", trailing: "" } as const);
+
+	function printLeadingComment(comment: AnyComment) {
+		if (is_Attribute(comment) && !comment.inner) {
+			const printed = printComment(comment);
+			return [printed, " "];
+		}
+		hadLeadingBlockComment ||= is_BlockCommentKind(comment) && hasBreaklineBefore(comment);
+		return [
+			printComment(comment),
+			is_BlockCommentKind(comment)
+				? hasBreaklineAfter(comment) //
+					? hadLeadingBlockComment
+						? hardline
+						: line
+					: " "
+				: hardline,
+			hasNewline(skipNewline(skipSpaces(end(comment)))) ? hardline : "",
+		];
+	}
+
+	function printTrailingComment(comment: AnyComment) {
+		const printed = printComment(comment);
+		return hasBreaklineBefore(comment)
+			? lineSuffix([hardline, isPreviousLineEmpty(comment) ? hardline : "", printed])
+			: is_BlockCommentNode(comment)
+			? [" ", printed]
+			: lineSuffix([" ", printed, hasTrailingLineComment === (hasTrailingLineComment = true) ? hardline : breakParent]);
+	}
+}
+
+export function getPostLeadingComment(comment: AnyComment) {
+	// console.log(comment.loc.url());
+	// is_BlockCommentKind(comment)
+	// 	? hasBreaklineAfter(comment) //
+	// 		? hasBreaklineBefore(comment)
+	// 			? hardline
+	// 			: line
+	// 		: " "
+	// 	: hardline,
+	return hasNewline(skipNewline(skipSpaces(end(comment)))) ? hardline : "";
+}
+
+export function withComments<D extends Doc>(node: Node, printed: D, ignored?: Set<AnyComment>): D | Doc[] {
+	__DEV__: assertPathAtNode("withComments", node);
+	const { leading, trailing } = printCommentsSeparately(ignored);
+	return leading || trailing ? [...leading!, printed, ...trailing!] : printed;
+	// return needsOuterParens(node) ? group(["(", indent([softline, parts]), softline, ")"]) : parts;
+	// return parts;
+}
+export function getComments(node: Node, ...args: Parameters<typeof getCommentTestFunction>): AnyComment[] {
+	__DEV__: Narrow<Node & { comments?: AnyComment[] }>(node);
+	// if (!node || !node.comments) return [];
+	// if (args.length === 0) return node.comments;
+	// return args.length > 0 ? node.comments.filter(getCommentTestFunction(...args)) : node.comments;
+	return node && node.comments //
+		? args.length > 0
+			? node.comments.filter(getCommentTestFunction(...args))
+			: node.comments
+		: [];
+}
+
+export function getFirstComment(node: Node, flags: CF, fn?: (comment: AnyComment) => boolean): AnyComment | undefined {
+	const r = getComments(node, flags | CF.First, fn);
+	return r.length === 0 ? undefined : r[0];
+}
+
+export function escapeComments(flags: number, fn?: (comment: AnyComment) => boolean) {
+	const comments = getAllComments().filter(getCommentTestFunction(flags, fn)) as AnyComment[];
+	comments.forEach(setDidPrintComment);
+	return new Set(comments);
+}
+
+export const enum CF {
+	Leading = 1 << 1,
+	Trailing = 1 << 2,
+	Dangling = 1 << 3,
+	Block = 1 << 4,
+	Line = 1 << 5,
+	PrettierIgnore = 1 << 6,
+	First = 1 << 7,
+	Last = 1 << 8,
+}
+export function isPrettierIgnoreComment(comment: AnyComment) {
+	return is_Comment(comment) && /^\s*prettier-ignore\s*/.test(comment.value) && !comment.unignore;
+}
+export function isPrettierIgnoreAttribute(node: Node): node is MutatedAttribute {
+	return is_Attribute(node) && /^\s*rustfmt::skip\s*$/.test(node.value);
+}
+function getCommentTestFunction(flags: CF, fn?: (comment: AnyComment) => boolean) {
+	return function (comment: AnyComment, index: number, comments: AnyComment[]) {
+		__DEV__: Narrow<number>(flags), assert(handled(comment));
+		return !(
+			(flags & CF.Leading && !isLeading(comment)) ||
+			(flags & CF.Trailing && !isTrailing(comment)) ||
+			(flags & CF.Dangling && !isDangling(comment)) ||
+			(flags & CF.Block && !is_BlockCommentKind(comment)) ||
+			(flags & CF.Line && !is_LineCommentKind(comment)) ||
+			(flags & CF.First && index !== 0) ||
+			(flags & CF.Last && !iLast(index, comments)) ||
+			(flags & CF.PrettierIgnore && !(isPrettierIgnoreComment(comment) || isPrettierIgnoreAttribute(comment))) ||
+			(fn && !fn(comment))
+		);
+	};
+}
+
+export function hasComment(node: Node, flags: number = 0, fn?: (comment: AnyComment) => boolean) {
+	if ("comments" in node && node.comments!.length > 0) {
+		return flags || fn ? (node.comments as AnyComment[]).some(getCommentTestFunction(flags, fn)) : true;
+	}
+	return false;
+}
+export function hasNewlineInRange(leftIndex: number, rightIndex: number) {
+	__DEV__: assert(leftIndex <= rightIndex);
+	const text = getContext().options.originalText;
+	for (var i = leftIndex; i < rightIndex; ++i) if (text.charCodeAt(i) === 10) return true;
+	return false;
+}
+export function isNextLineEmpty(node: Node) {
+	return isNextLineEmptyAfterIndex(end(node));
+}
+export function isNextLineEmptyAfterIndex(index: number | false) {
+	let oldIdx: number | false = -1;
+	let idx: number | false = index;
+	while (idx !== oldIdx) {
+		oldIdx = idx;
+		idx = skipToLineEnd(idx);
+		idx = skipBlockComment(idx);
+		idx = skipSpaces(idx);
+		idx = skipParens(idx);
+	}
+	idx = skipLineComment(idx);
+	idx = skipParens(idx);
+	idx = skipNewline(idx);
+	idx = skipParens(idx);
+	return idx !== false && hasNewline(idx);
+}
+export function hasNewline(index: number | false, backwards = false) {
+	if (index === false) return false;
+	const i = skipSpaces(index, backwards);
+	return i !== false && i !== skipNewline(i, backwards);
+}
+function skipLineComment(index: number | false) {
+	if (index === false) return false;
+	const { commentSpans, originalText } = getContext().options;
+	if (commentSpans.has(index) && originalText.charCodeAt(index + 1) === 47 /** "/" */)
+		return skipEverythingButNewLine(commentSpans.get(index)!);
+	return index;
+}
+function skipBlockComment(index: number | false) {
+	if (index === false) return false;
+	const { commentSpans, originalText } = getContext().options;
+	if (commentSpans.has(index) && originalText.charCodeAt(index + 1) === 42 /** "*" */) return commentSpans.get(index)!;
+	return index;
+}
+const [skipSpaces, skipToLineEnd, skipEverythingButNewLine] = [/[ \t]/, /[,; \t]/, /[^\r\n]/].map(function (re) {
+	return function (index: number | false, backwards = false) {
+		if (index === false) return false;
+		const { originalText: text } = getContext().options;
+		let cursor = index;
+		while (cursor >= 0 && cursor < text.length) {
+			if (re.test(text.charAt(cursor))) backwards ? cursor-- : cursor++;
+			else return cursor;
+		}
+		return cursor === -1 || cursor === text.length ? cursor : false;
+	};
+});
+
+function skipNewline(index: number | false, backwards = false) {
+	if (index === false) return false;
+	const { originalText } = getContext().options;
+	const atIndex = originalText.charCodeAt(index);
+	if (backwards) {
+		if (originalText.charCodeAt(index - 1) === 13 && atIndex === 10) return index - 2;
+		if (atIndex === 10) return index - 1;
+	} else {
+		if (atIndex === 13 && originalText.charCodeAt(index + 1) === 10) return index + 2;
+		if (atIndex === 10) return index + 1;
+	}
+	return index;
+}
+
+function skipParens(index: number | false, backwards = false) {
+	return index;
+	// if (index === false) return false;
+	// const { parensPositions } = getContext().options;
+	// while (parensPositions.has(index)) backwards ? index-- : index++;
+	// return index;
+}
+
+export function getNextNonSpaceNonCommentCharacterIndex(node: Node) {
+	return getNextNonSpaceNonCommentCharacterIndexWithStartIndex(end(node));
+}
+function getNextNonSpaceNonCommentCharacterIndexWithStartIndex(i: number) {
+	let oldIdx = -1;
+	let nextIdx = i;
+	while (nextIdx !== oldIdx) {
+		oldIdx = nextIdx;
+		nextIdx = skipSpaces(nextIdx) as number;
+		nextIdx = skipBlockComment(nextIdx) as number;
+		nextIdx = skipLineComment(nextIdx) as number;
+		nextIdx = skipNewline(nextIdx) as number;
+		nextIdx = skipParens(nextIdx) as number;
+	}
+	return nextIdx;
+}
+export function getNextNonSpaceNonCommentCharacter(node: Node) {
+	return getContext().options.originalText.charAt(getNextNonSpaceNonCommentCharacterIndex(node));
+}
+
+interface CommentContext {
+	comment: AnyComment;
+	precedingNode: Node | undefined;
+	enclosingNode: Node | undefined;
+	followingNode: Node | undefined;
+	text: string;
+	options: CustomOptions;
+	ast: Node;
+	isLastComment: boolean;
+}
+
+function handled(comment: AnyComment) {
+	return "printed" in comment;
+}
+function handleCommon(ctx: CommentContext): boolean {
+	{
+		const { comment, precedingNode, enclosingNode, followingNode } = ctx;
+		if (!enclosingNode) {
+			ctx.enclosingNode = ctx.comment.loc.src.program;
+		} else if (enclosingNode && is_NodeWithBodyOrCases(enclosingNode)) {
+			const body = getBodyOrCases(enclosingNode);
+			if (body) {
+				if (is_ExpressionWithBodyOrCases(enclosingNode) && enclosingNode.label) {
+					if (ctx.precedingNode === enclosingNode.label) {
+						ctx.precedingNode = undefined;
+					}
+					if (followingNode === enclosingNode.label) {
+						ctx.followingNode = undefined;
+					}
+				}
+				if (comment.loc.isBefore(body)) {
+					if (followingNode && body.loc.contains(followingNode)) {
+						ctx.followingNode = undefined;
+					}
+					if (!ctx.precedingNode && !ctx.followingNode) {
+						addLeadingComment(enclosingNode, comment);
+						return true;
+					}
+				} else if (comment.loc.isAfter(body)) {
+					if (precedingNode && body.loc.contains(precedingNode)) {
+						ctx.precedingNode = undefined;
+					}
+					if (!ctx.precedingNode && !ctx.followingNode) {
+						addTrailingComment(enclosingNode, comment);
+						return true;
+					}
+				} else if (body.loc.contains(comment)) {
+					if (precedingNode && !body.loc.contains(precedingNode)) {
+						ctx.precedingNode = undefined;
+					}
+					if (followingNode && !body.loc.contains(followingNode)) {
+						ctx.followingNode = undefined;
+					}
+				}
+			}
+		}
+	}
+	for (const fn of [
+		handleMixedInOuterAttributeComments,
+		handleAttributeComments,
+		handleDanglingComments,
+		handleFunctionComments,
+		handleMacroRuleComments,
+		handleStructLiteralComments,
+		handleVariableDeclaratorComments,
+		handleIfBlockExpressionComments,
+		handleMemberExpressionComments,
+		handleStatementComments,
+		handleFlowControlComments,
+		handleBadComments,
+	]) {
+		fn(ctx);
+		if (handled(ctx.comment)) {
+			// console.log(ctx.comment.loc.url(), fn.name);
+			return true;
+		}
+	}
+
+	const { precedingNode, followingNode, comment } = ctx;
+
+	if (isStartOfLine(comment)) {
+		if (followingNode) {
+			addLeadingComment(followingNode, comment);
+		} else if (precedingNode) {
+			addTrailingComment(precedingNode, comment);
+		} else {
+			exit.never(ctx);
+		}
+	} else if (isEndOfLine(comment)) {
+		if (precedingNode) {
+			addTrailingComment(precedingNode, comment);
+		} else if (followingNode) {
+			addLeadingComment(followingNode, comment);
+		} else {
+			exit.never(ctx);
+		}
+	} else {
+		if (precedingNode && followingNode) {
+			return false;
+		} else if (precedingNode) {
+			addTrailingComment(precedingNode, comment);
+		} else if (followingNode) {
+			addLeadingComment(followingNode, comment);
+		} else {
+			exit.never(ctx);
+		}
+	}
+	return handled(ctx.comment);
+}
+export function handleOwnLineComment(ctx: CommentContext) {
+	return handleCommon(ctx);
+}
+export function handleEndOfLineComment(ctx: CommentContext) {
+	const { precedingNode, enclosingNode, comment } = ctx;
+	if (
+		// handleCallExpressionComments
+		precedingNode &&
+		enclosingNode &&
+		is_CallExpression_or_CallLikeMacroInvocation(enclosingNode) &&
+		enclosingNode.arguments.length > 0 &&
+		precedingNode === (enclosingNode.typeArguments ? last_of(enclosingNode.typeArguments) : enclosingNode.callee)
+	) {
+		addLeadingComment(enclosingNode.arguments[0], comment);
+		return true;
+	} else if (
+		// handlePropertyComments
+		enclosingNode &&
+		is_StructLiteralProperty(enclosingNode)
+	) {
+		addLeadingComment(enclosingNode, comment);
+		return true;
+	} else {
+		return handleCommon(ctx);
+	}
+}
+
+export function handleRemainingComment(ctx: CommentContext) {
+	return handleCommon(ctx);
+}
+
+function handleStructLiteralComments({ enclosingNode, followingNode, comment }: CommentContext) {
+	if (enclosingNode && is_StructLiteralPropertySpread(enclosingNode) && followingNode === enclosingNode.expression) {
+		addLeadingComment(enclosingNode, comment);
+	}
+}
+
+function handleVariableDeclaratorComments({ enclosingNode, followingNode, comment }: CommentContext) {
+	if (
+		enclosingNode &&
+		(is_xVariableEqualishLike(enclosingNode) || is_ReassignmentNode(enclosingNode)) &&
+		followingNode &&
+		(is_BlockCommentKind(comment) ||
+			nisAnyOf(followingNode, [
+				NodeType.StructLiteral,
+				NodeType.StructPattern,
+				NodeType.TupleLiteral,
+				NodeType.TypeTuple,
+				NodeType.TuplePattern,
+				NodeType.ArrayLiteral,
+				NodeType.ArrayPattern,
+				NodeType.SizedArrayLiteral,
+				NodeType.TypeSizedArray,
+			]))
+	) {
+		addLeadingComment(followingNode, comment);
+	}
+}
+
+function handleMixedInOuterAttributeComments({ precedingNode, enclosingNode, followingNode, comment }: CommentContext) {
+	if (enclosingNode && hasOuterAttributes(enclosingNode) && end(comment) <= ownStart(enclosingNode)) {
+		if (isPrettierIgnoreComment(comment) || isPrettierIgnoreAttribute(comment)) {
+			setPrettierIgnoreTarget(enclosingNode, comment);
+		}
+		if (isEndOfLine(comment)) {
+			__DEV__: assert(!!precedingNode && is_Attribute(precedingNode), "", precedingNode);
+			if (shouldPrintOuterAttributesAbove(enclosingNode)) {
+				// #[attr] // comment
+				// node
+				addTrailingComment(precedingNode, comment);
+			} else {
+				// #[attr] /* comment */ node
+				addLeadingComment(followingNode || enclosingNode, comment);
+			}
+		} else {
+			// __DEV__: assert(isStartOfLine(comment));
+			if (followingNode && end(followingNode) <= ownStart(enclosingNode)) {
+				addLeadingComment(followingNode, comment);
+			} else if (precedingNode && enclosingNode.loc.contains(precedingNode)) {
+				addTrailingComment(precedingNode, comment);
+			} else {
+				addLeadingComment(enclosingNode, comment);
+			}
+		}
+	}
+}
+function handleAttributeComments({ precedingNode, enclosingNode, followingNode, comment, ast }: CommentContext) {
+	if (is_AttributeOrDocComment(comment)) {
+		if (
+			comment.inner &&
+			enclosingNode &&
+			is_FunctionDeclaration(enclosingNode) &&
+			(!followingNode || !is_StatementNode(followingNode)) &&
+			(!precedingNode || !is_StatementNode(precedingNode))
+		) {
+			if (enclosingNode.body) {
+				if (canAttachCommentInLocArray(enclosingNode.body)) {
+					addDanglingComment(enclosingNode, comment, DCM["body"]);
+				} else {
+					addLeadingComment(enclosingNode.body[0], comment);
+				}
+			} else {
+				addLeadingComment(enclosingNode, comment);
+			}
+		} else {
+			// if (comment.loc.url().startsWith("tests/samples/macro/attr.rs") && getContext().options.danglingAttributes.includes(comment)) {
+			// 	// debugger;
+			// 	console.log({
+			// 		comment: comment.loc.url(),
+			// 		precedingNode: precedingNode?.loc.url(),
+			// 		enclosingNode: enclosingNode?.loc.url(),
+			// 		followingNode: followingNode?.loc.url(),
+			// 	});
+			// }
+			if (followingNode) {
+				addLeadingComment(followingNode, comment);
+			} else if (enclosingNode) {
+				for (var key in DCM)
+					if (key in enclosingNode) {
+						addDanglingComment(enclosingNode, comment, key as DCM);
+						return;
+					}
+			} else {
+				addDanglingComment(ast, comment, DCM["body"]);
+			}
+		}
+	}
+}
+
+function handleBadComments({ precedingNode, enclosingNode, followingNode, ast, comment }: CommentContext) {
+	if (!enclosingNode) {
+		// console.log(comment.loc.url());
+		if (followingNode) {
+			addLeadingComment(followingNode, comment);
+		} else if (precedingNode) {
+			addTrailingComment(precedingNode, comment);
+		} else {
+			addDanglingComment(enclosingNode || ast, comment, DCM["body"]);
+		}
+	} else if (!precedingNode && !followingNode) {
+		if (enclosingNode && enclosingNode !== ast) {
+			addLeadingComment(enclosingNode, comment);
+		} else {
+			addDanglingComment(ast, comment, DCM["body"]);
+		}
+	}
+}
+function is_ABI_Comment({ precedingNode, enclosingNode, comment }: CommentContext) {
+	return (
+		is_CommentOrDocComment(comment) &&
+		((precedingNode && is_ExternSpecifier(precedingNode)) || (enclosingNode && is_ExternSpecifier(enclosingNode)))
+	);
+}
+function handleFlowControlComments({ precedingNode, enclosingNode, followingNode, comment }: CommentContext) {
+	if (enclosingNode && is_FlowControlExpression(enclosingNode)) {
+		if (!precedingNode && (isOwnLine(comment) || isEndOfLine(comment)) && !followingNode) {
+			addLeadingComment(enclosingNode, comment);
+		}
+	}
+}
+function handleFunctionComments(ctx: CommentContext) {
+	const { precedingNode, enclosingNode, followingNode, comment } = ctx;
+	if (enclosingNode && is_FunctionNode(enclosingNode)) {
+		if (
+			is_FunctionDeclaration(enclosingNode) &&
+			((!is_ABI_Comment(ctx) && comment.loc.isBefore(enclosingNode.generics || enclosingNode.id)) ||
+				(enclosingNode.generics && comment.loc.isBetween(enclosingNode.generics, enclosingNode.parameters)))
+		) {
+			addLeadingComment(enclosingNode, comment);
+		} else if (
+			!enclosingNode.returnType &&
+			comment.loc.isBetween(
+				enclosingNode.parameters,
+				is_FunctionDeclaration(enclosingNode) ? enclosingNode.body! : enclosingNode.expression
+			)
+		) {
+			if (is_FunctionDeclaration(enclosingNode)) {
+				addCommentToBlock(enclosingNode, comment);
+			} else {
+				addLeadingComment(enclosingNode.expression, comment);
+			}
+		} else if (
+			precedingNode && //
+			enclosingNode.parameters.loc.contains(comment)
+		) {
+			if (precedingNode === getLastParameter(enclosingNode)) {
+				addTrailingComment(precedingNode, comment);
+			}
+		} else if (
+			followingNode &&
+			isStartOfLine(comment) &&
+			comment.loc.isAfter(enclosingNode.parameters) &&
+			(!is_FunctionDeclaration(enclosingNode) || !enclosingNode.whereBounds || comment.loc.isAfter(enclosingNode.whereBounds!)) &&
+			(!enclosingNode.returnType || comment.loc.isAfter(enclosingNode.returnType)) &&
+			followingNode === (is_FunctionDeclaration(enclosingNode) ? enclosingNode.body?.[0] : enclosingNode.expression)
+		) {
+			addLeadingComment(followingNode, comment);
+		}
+	}
+}
+function handleMacroRuleComments(ctx: CommentContext) {
+	const { precedingNode, enclosingNode, followingNode, comment } = ctx;
+	if (enclosingNode && is_MacroRule(enclosingNode)) {
+		if (enclosingNode.transform.loc.contains(comment)) {
+			__DEV__: assert(enclosingNode.transform.length > 0);
+			if (!precedingNode || !enclosingNode.transform.loc.contains(precedingNode)) {
+				__DEV__: assert(!!followingNode && enclosingNode.transform.loc.contains(followingNode));
+				addLeadingComment(followingNode, comment);
+			}
+		} else if (enclosingNode.match.loc.contains(comment)) {
+			__DEV__: assert(enclosingNode.match.length > 0);
+			if (!followingNode || !enclosingNode.match.loc.contains(followingNode)) {
+				__DEV__: assert(!!precedingNode && enclosingNode.match.loc.contains(precedingNode));
+				addTrailingComment(precedingNode!, comment);
+			}
+		}
+	}
+}
+
+function handleStatementComments(ctx: CommentContext) {
+	const { precedingNode, comment } = ctx;
+	if (isEndOfLine(comment) && precedingNode && (is_StatementNode(precedingNode) || precedingNode.loc.sliceText().endsWith(";"))) {
+		addTrailingComment(precedingNode, comment);
+	}
+}
+
+function addCommentToBlock(block: NodeWithBodyOrCases, comment: AnyComment) {
+	const body = getBodyOrCases(block);
+	__DEV__: assert(!!body);
+	if (body.length > 0) {
+		addLeadingComment(body![0], comment);
+	} else {
+		addDanglingComment(block, comment, DCM["body"]);
+	}
+}
+
+function handleIfBlockExpressionComments(ctx: CommentContext) {
+	const { comment, enclosingNode } = ctx;
+	if (enclosingNode && is_IfBlockExpression(enclosingNode)) {
+		const { condition, body, else: else_ } = enclosingNode;
+		if (comment.loc.isBefore(condition)) {
+			addLeadingComment(condition, comment);
+		} else if (comment.loc.isBetween(condition, body)) {
+			addTrailingComment(condition, comment);
+		} else if (else_ && comment.loc.isBetween(body, else_)) {
+			if (is_IfBlockExpression(else_)) {
+				addLeadingComment(else_.condition, comment);
+			} else {
+				addCommentToBlock(else_, comment);
+			}
+		}
+	}
+}
+
+function handleMemberExpressionComments({ comment, precedingNode, enclosingNode }: CommentContext) {
+	if (enclosingNode && is_MemberAccessLike(enclosingNode)) {
+		if (isStartOfLine(comment) || !precedingNode) addLeadingComment(enclosingNode, comment);
+		else addTrailingComment(precedingNode, comment);
+		return true;
+	}
+
+	return false;
+}
+
+function handleDanglingComments({ comment, enclosingNode }: CommentContext) {
+	if (enclosingNode) {
+		for (var key in DCM) {
+			if (key in enclosingNode) {
+				var arr: LocArray = enclosingNode[key];
+				if (is_LocArray(arr) && canAttachCommentInLocArray(arr) && arr.loc.contains(comment)) {
+					addDanglingComment(enclosingNode, comment, key as DCM);
+					return;
+				}
+			}
+		}
+	}
+}
+
+function canAttachCommentInLocArray(arr: LocArray) {
+	return arr.length === 0 || arr.every((node) => !canAttachComment(node));
+}
+
+function isOwnLine(comment: AnyComment) {
+	return isStartOfLine(comment) && hasBreaklineAfter(comment);
+}
+function isStartOfLine(comment: AnyComment) {
+	return comment.placement === "ownLine";
+}
+function isEndOfLine(comment: AnyComment) {
+	return comment.placement === "endOfLine";
+}
+export function isDangling(comment: AnyComment) {
+	__DEV__: assert(handled(comment));
+	return !comment.leading && !comment.trailing;
+}
+export function isLeading(comment: AnyComment) {
+	__DEV__: assert(handled(comment));
+	return comment.leading && !comment.trailing;
+}
+export function isTrailing(comment: AnyComment) {
+	__DEV__: assert(handled(comment));
+	return !comment.leading && comment.trailing;
+}
+
+export function print_comment(comment: CommentOrDocComment) {
+	__DEV__: Narrow<PrettierCommentInfo>(comment);
+
+	const doc = is_BlockCommentNode(comment)
+		? isIndentableBlockComment(comment.value)
+			? [
+					(!handled(comment) || isTrailing(comment)) && !hasBreaklineBefore(comment) ? hardline : "",
+					getCommentStart(comment),
+					...comment.value.split(/\n/g).map((line, i, a) =>
+						i === 0 //
+							? [line.trimEnd(), hardline]
+							: !iLast(i, a)
+							? [" " + line.trim(), hardline]
+							: " " + line.trimStart()
+					),
+					"*/",
+			  ]
+			: [
+					getCommentStart(comment), //
+					join(literalline, comment.value.split(/\n/g)),
+					"*/",
+			  ]
+		: [getCommentStart(comment), comment.value.trimEnd()];
+
+	return handled(comment) && isDangling(comment) //
+		? [doc, getPostLeadingComment(comment)]
+		: doc;
+
+	function getCommentStart(comment: CommentOrDocComment) {
+		return is_Comment(comment)
+			? is_BlockCommentKind(comment)
+				? "/*"
+				: "//"
+			: is_BlockCommentKind(comment)
+			? isInner(comment)
+				? "/*!"
+				: "/**"
+			: isInner(comment)
+			? "//!"
+			: "///";
+	}
+	function isIndentableBlockComment(value: string) {
+		const lines = `*${value}*`.split(/\n/g);
+		return lines.length > 1 && lines.every((line) => /^\s*\*/.test(line));
+	}
+}

frontend/src/utils/prettier/plugins/rust/format/complexity.ts

@@ -0,0 +1,282 @@
+import {
+	ForLtParametersBody,
+	FunctionSpread,
+	GenericParameterDeclaration,
+	MaybeGenericArgsTarget,
+	MissingNode,
+	Node,
+	NodeType,
+	TypeBound,
+	TypeBoundsConstaint,
+	TypeCallArgument,
+	TypeNamespaceTargetNoSelector,
+	TypeNode,
+} from "jinx-rust";
+import {
+	getAstPath,
+	getOwnChildAstPath,
+	is_BareTypeTraitBound,
+	is_FunctionSpread,
+	is_LetScrutinee,
+	is_Literal,
+	is_MissingNode,
+	is_TypeBoundsStandaloneNode,
+	is_TypeFunctionNode,
+	is_TypeNode,
+	is_VariableDeclarationNode,
+} from "jinx-rust/utils";
+import { exit, has_key_defined, last_of, spliceAll } from "../utils/common";
+import { canBreak } from "./external";
+import { getContext, getNode, getOptions, getPrintFn } from "./plugin";
+
+let DEPTH = 0;
+const ANCESTRY: Node[] = [];
+const LONE_SHORT_ARGUMENT_THRESHOLD_RATE = 0.25;
+
+export function withCheckContext<R>(fn: () => R): R {
+	if (0 === DEPTH) {
+		return fn();
+	} else {
+		DEPTH = 0;
+		const prev = spliceAll(ANCESTRY);
+		try {
+			return fn();
+		} finally {
+			DEPTH = ANCESTRY.push(...prev);
+		}
+	}
+}
+
+export function is_short(str: string) {
+	return str.length <= LONE_SHORT_ARGUMENT_THRESHOLD_RATE * getOptions().printWidth;
+}
+function print(target: Node) {
+	const current = getNode();
+	const keys: (string | number)[] = [...getAstPath(ANCESTRY[0], getNode())];
+	for (let i = 1; i < ANCESTRY.length; i++) keys.push(...getOwnChildAstPath(ANCESTRY[i - 1], ANCESTRY[i]));
+	keys.push(...getOwnChildAstPath(last_of(ANCESTRY), target));
+	try {
+		return getContext().path.call(() => getPrintFn(target)(), ...keys);
+	} catch (e) {
+		console.log({ current, target, keys, ANCESTRY });
+		throw e;
+	}
+}
+
+function IsSimpleFunction<T extends Node>(fn: (node: T) => boolean): (node: T) => boolean {
+	return function (node: T) {
+		if (0 !== DEPTH && node === ANCESTRY[DEPTH - 1]) {
+			return fn(node);
+		}
+
+		if (DEPTH >= 2) {
+			return isShortBasic(node);
+		}
+
+		try {
+			return fn((ANCESTRY[DEPTH++] = node) as any);
+		} finally {
+			ANCESTRY.length = --DEPTH;
+		}
+	} as any;
+}
+
+function HasComplexFunction<T extends Node>(fn: (node: T) => boolean): (node: T) => boolean {
+	return function (node: T) {
+		if (0 !== DEPTH && node === ANCESTRY[DEPTH - 1]) {
+			return fn(node);
+		}
+
+		if (DEPTH >= 2) {
+			return !isShortBasic(node);
+		}
+
+		try {
+			return fn((ANCESTRY[DEPTH++] = node) as any);
+		} finally {
+			ANCESTRY.length = --DEPTH;
+		}
+	} as any;
+}
+
+const isShortBasic = (node: Node) => {
+	switch (node.nodeType) {
+		case NodeType.MissingNode:
+			return true;
+		case NodeType.Identifier:
+		case NodeType.Index:
+		case NodeType.LtIdentifier:
+		case NodeType.LbIdentifier:
+		case NodeType.McIdentifier:
+			return is_short(node.name);
+		case NodeType.Literal:
+			return is_short(node.value) && !/\n/.test(node.value);
+	}
+	return false;
+};
+
+export const isSimpleType = IsSimpleFunction<FunctionSpread | TypeNode | MissingNode>((node): boolean => {
+	switch (node.nodeType) {
+		case NodeType.MissingNode:
+		case NodeType.FunctionSpread:
+			return true;
+		case NodeType.MacroInvocation:
+			return false;
+		case NodeType.Identifier:
+		case NodeType.TypeNever:
+		case NodeType.TypeInferred:
+			return true;
+		case NodeType.TypePath:
+			return isShortBasic(node.segment) && (!node.namespace || isSimpleType(node.namespace));
+		case NodeType.TypeCall:
+			return isSimpleType(node.typeCallee) && !hasComplexTypeArguments(node);
+		case NodeType.ExpressionTypeSelector:
+			return isSimpleType(node.typeTarget) && (!node.typeExpression || isSimpleType(node.typeExpression));
+		case NodeType.TypeDynBounds:
+			return !hasComplexTypeBounds(node);
+		case NodeType.TypeImplBounds:
+			return !hasComplexTypeBounds(node);
+		case NodeType.TypeFnPointer: {
+			const param = node.parameters[0];
+			return (
+				(!node.extern || !node.extern.abi || isShortBasic(node.extern.abi)) &&
+				!hasComplexLtParameters(node) &&
+				(node.parameters.length === 0 ||
+					(node.parameters.length === 1 &&
+						(is_FunctionSpread(param) ||
+							(!is_TypeFunctionNode(param.typeAnnotation) && isSimpleType(param.typeAnnotation))))) &&
+				(!node.returnType || isSimpleType(node.returnType))
+			);
+		}
+		case NodeType.TypeFunction:
+			return isSimpleType(node.callee) && node.parameters.every(isSimpleType) && (!node.returnType || isSimpleType(node.returnType));
+		case NodeType.TypeSizedArray:
+			return isSimpleType(node.typeExpression) && isShortBasic(node.sizeExpression);
+		case NodeType.TypeSlice:
+			return isSimpleType(node.typeExpression);
+		case NodeType.TypeTuple:
+			return node.items.length === 0 || (node.items.length === 1 && isSimpleType(node.items[0]));
+		case NodeType.TypeReference:
+		case NodeType.TypeDereferenceMut:
+		case NodeType.TypeDereferenceConst:
+		case NodeType.TypeParenthesized:
+			return isSimpleType(node.typeExpression);
+		default:
+			__DEV__: exit.never(node);
+			return false;
+	}
+});
+
+export const hasComplexTypeBounds = HasComplexFunction<Extract<Node, TypeBoundsConstaint>>((node) => {
+	return !!node.typeBounds && node.typeBounds.length > 1 && !node.typeBounds.every(isSimpleTypeBound);
+});
+
+export const isSimpleTypeBound = (node: TypeBound): boolean => {
+	switch (node.nodeType) {
+		case NodeType.TypeParenthesized:
+			return isSimpleTypeBound(node.typeExpression);
+		// #Lifetime
+		case NodeType.LtIdentifier:
+		case NodeType.LtElided:
+		case NodeType.LtStatic:
+			return true;
+		case NodeType.TypeTraitBound:
+			return is_BareTypeTraitBound(node) && isSimpleTypeNamespaceTargetNoSelector(node.typeExpression);
+		default:
+			__DEV__: exit.never(node);
+			return false;
+	}
+	function isSimpleTypeNamespaceTargetNoSelector(node: TypeNamespaceTargetNoSelector): boolean {
+		switch (node.nodeType) {
+			case NodeType.Identifier:
+				return true;
+			case NodeType.TypePath:
+				return undefined === node.namespace || isSimpleTypeNamespaceTargetNoSelector(node.namespace);
+			case NodeType.TypeCall:
+				return false;
+			case NodeType.TypeFunction:
+				return isSimpleTypeNamespaceTargetNoSelector(node.callee) && node.parameters.length === 0 && !node.returnType;
+			default:
+				__DEV__: exit.never(node);
+				return false;
+		}
+	}
+};
+
+const isSimpleTypeArgument = IsSimpleFunction<TypeCallArgument>((node) => {
+	if (is_TypeNode(node)) {
+		return isSimpleType(node);
+	}
+	switch (node.nodeType) {
+		// #Lifetime
+		case NodeType.LtIdentifier:
+		case NodeType.LtElided:
+		case NodeType.LtStatic:
+		case NodeType.Literal:
+			return true;
+		case NodeType.MinusExpression:
+			return is_Literal(node.expression);
+		case NodeType.BlockExpression:
+			return false; //willBreak(getPrintFn(node)("body"));
+		case NodeType.TypeCallNamedArgument:
+			return isSimpleType(node.typeExpression);
+		case NodeType.TypeCallNamedBound:
+			return isSimpleType(node.typeTarget) && !hasComplexTypeBounds(node);
+		default:
+			__DEV__: exit.never(node);
+			return false;
+	}
+});
+
+export const hasComplexTypeArguments = HasComplexFunction<Extract<Node, MaybeGenericArgsTarget>>((node) =>
+	!node.typeArguments || node.typeArguments.length === 0
+		? false
+		: node.typeArguments.length === 1
+		? (() => {
+				const arg = node.typeArguments[0];
+				return is_TypeBoundsStandaloneNode(arg) || canBreak(print(arg));
+		  })()
+		: true
+);
+
+export const hasComplexLtParameters = HasComplexFunction<Extract<Node, ForLtParametersBody>>((node) => {
+	const ltParameters = node.ltParameters;
+	if (!ltParameters || ltParameters.length === 0) {
+		return false;
+	}
+	if (ltParameters.length === 1) {
+		const arg = ltParameters[0];
+		if (arg.ltBounds && arg.ltBounds.length > 1) {
+			return true;
+		}
+
+		return false;
+	}
+	return true;
+});
+
+export const isShortGenericParameterDeclaration = IsSimpleFunction<GenericParameterDeclaration>((node) => {
+	switch (node.nodeType) {
+		case NodeType.GenericTypeParameterDeclaration:
+			return !node.typeBounds && !node.typeDefault;
+		case NodeType.ConstTypeParameterDeclaration:
+			return (!node.typeAnnotation || is_MissingNode(node)) && !node.typeDefault;
+		case NodeType.GenericLtParameterDeclaration:
+			return !node.ltBounds;
+		default:
+			exit.never();
+	}
+});
+
+export const hasComplexGenerics = HasComplexFunction<Node>((node) => {
+	return has_key_defined(node, "generics") && node.generics.length > 0 && !node.generics.every(isShortGenericParameterDeclaration);
+});
+
+export const hasComplexTypeAnnotation = HasComplexFunction<Node>((node) => {
+	if (is_VariableDeclarationNode(node) && !is_LetScrutinee(node)) {
+		const { typeAnnotation } = node;
+		return !!typeAnnotation && !is_MissingNode(typeAnnotation) && !isSimpleType(typeAnnotation);
+	} else {
+		return false;
+	}
+});

frontend/src/utils/prettier/plugins/rust/format/external.ts

@@ -0,0 +1,126 @@
+import { Attribute, AttributeOrDocComment, Comment, DocCommentAttribute, LocArray, MemberExpression, Node, SourceFile } from "jinx-rust";
+import { PickProps } from "jinx-rust/utils";
+import type { Doc, ParserOptions, Printer } from "prettier";
+import { doc } from "prettier";
+import { AssertTypesEq } from "../utils/common";
+
+export type { Doc, ParserOptions, Plugin, Printer } from "prettier";
+
+
+export const {
+	join,
+	line,
+	softline,
+	hardline,
+	literalline,
+	group,
+	conditionalGroup,
+	fill,
+	lineSuffix,
+	lineSuffixBoundary,
+	cursor,
+	breakParent,
+	ifBreak,
+	trim,
+	indent,
+	indentIfBreak,
+	align,
+	addAlignmentToDoc,
+	markAsRoot,
+	dedentToRoot,
+	dedent,
+	hardlineWithoutBreakParent,
+	literallineWithoutBreakParent,
+	label,
+} = doc.builders;
+
+export const {
+	willBreak,
+	traverseDoc,
+	findInDoc,
+	mapDoc,
+	removeLines,
+	stripTrailingHardline,
+} = doc.utils;
+
+// Fallback implementations for removed utils in prettier 3
+export const isConcat = (doc: any): boolean => Array.isArray(doc);
+export const getDocParts = (doc: any): any[] => Array.isArray(doc) ? doc : [doc];
+export const propagateBreaks = (doc: any): any => doc;
+export const normalizeParts = (parts: any[]): any[] => parts.flat();
+export const normalizeDoc = (doc: any): any => doc;
+export const cleanDoc = (doc: any): any => doc;
+export const canBreak = (doc: any): boolean => {
+	if (!doc) return false;
+	if (typeof doc === 'string') return false;
+	if (Array.isArray(doc)) return doc.some(canBreak);
+	if (doc.type === 'group' || doc.type === 'fill') return true;
+	return willBreak(doc);
+};
+
+export const Symbol_comments = Symbol.for("comments");
+
+export interface CustomOptions extends ParserOptions<Node> {
+	[Symbol_comments]: AnyComment[];
+	rsParsedFile: SourceFile;
+	commentSpans: Map<number, number>;
+	printer: Printer<Node>;
+	cursorNode: any;
+
+	comments: Comment[];
+	danglingAttributes: AttributeOrDocComment[];
+	actuallyMethodNodes: WeakSet<MemberExpression>;
+}
+
+export type NodeWithComments<T extends Node> = T & { comments: AnyComment[] };
+export interface MutatedComment extends Comment, PrettierCommentInfo {}
+export interface MutatedAttribute extends Attribute, PrettierCommentInfo {}
+export interface MutatedDocComment extends DocCommentAttribute, PrettierCommentInfo {}
+export type AnyComment = MutatedComment | MutatedAttribute | MutatedDocComment;
+
+type keyofDelimitedArrayProps<T> = T extends never ? never : keyof PickProps<T, LocArray<any, "()" | "[]" | "{}" | "<>">>;
+
+__DEV__: AssertTypesEq<keyof typeof DCM, keyofDelimitedArrayProps<Node>>();
+
+export enum DCM {
+	"arguments" = "arguments",
+	"parameters" = "parameters",
+	"items" = "items",
+	"properties" = "properties",
+	"members" = "members",
+	"body" = "body",
+	"cases" = "cases",
+	"typeArguments" = "typeArguments",
+	"ltParameters" = "ltParameters",
+	"generics" = "generics",
+	"specifiers" = "specifiers",
+	"rules" = "rules",
+	"match" = "match",
+	"transform" = "transform",
+	"segments" = "segments",
+}
+
+export interface PrettierCommentInfo {
+	trailing: boolean;
+	leading: boolean;
+	unignore: boolean;
+	printed: boolean;
+	placement: "ownLine" | "endOfLine" | "remaining";
+	// nodeDescription?: any;
+	marker?: DCM;
+}
+
+export interface AstPath<T = Node> {
+	stack: (Node | string | number)[];
+	callParent<R>(callback: (path: this) => R, count?: number): R;
+	getName(): PropertyKey | null;
+	getValue(): T;
+	getNode(count?: number): T | null;
+	getParentNode(count?: number): T | null;
+
+	match(...predicates: ((node: Node, name: string | null, number: number | null) => boolean)[]): boolean;
+
+	call<R>(callback: (path: AstPath, index: number, value: any) => R, ...props: (string | number)[]): R;
+	each(callback: (path: AstPath, index: number, value: any) => void, ...props: (string | number)[]): void;
+	map<R>(callback: (path: AstPath, index: number, value: any) => R, ...props: (string | number)[]): R[];
+}

frontend/src/utils/prettier/plugins/rust/format/plugin.ts

@@ -0,0 +1,367 @@
+import { AttributeOrComment, IfBlockExpression, Node, Program, rs } from "jinx-rust";
+import {
+	ArrayProps,
+	BoolProps,
+	NodeProps,
+	end,
+	hasAttributes,
+	insertNodes,
+	is_Attribute,
+	is_AttributeOrComment,
+	is_BlockCommentKind,
+	is_BlockCommentNode,
+	is_Comment,
+	is_DocCommentAttribute,
+	is_ElseBlock,
+	is_LineCommentNode,
+	is_MacroInvocation,
+	is_MacroRule,
+	is_MissingNode,
+	is_Node,
+	is_PunctuationToken,
+	is_UnionPattern,
+	start,
+} from "jinx-rust/utils";
+import { getCommentChildNodes, isTransformed, transform_ast } from "../transform";
+import { Narrow, assert, color, each, exit, iLast, is_array, map_tagged_template, print_string } from "../utils/common";
+import {
+	CF,
+	escapeComments,
+	getComments,
+	handleEndOfLineComment,
+	handleOwnLineComment,
+	handleRemainingComment,
+	hasBreaklineAfter,
+	hasComment,
+	isDangling,
+	isPrettierIgnoreAttribute,
+	setDidPrintComment,
+	withComments,
+} from "./comments";
+import { withCheckContext } from "./complexity";
+import { isNoopExpressionStatement, maybeEmptyLine } from "./core";
+import { AstPath, CustomOptions, Doc, Plugin, Symbol_comments, group, hardline, indent, line, softline, ParserOptions } from "./external";
+import { printer } from "./printer";
+import { needsInnerParens, needsOuterSoftbreakParens, shouldPrintOuterAttributesAbove } from "./styling";
+
+export function is_printing_macro() {
+	return getContext().path.stack.some((node) => is_Node(node) && (is_MacroInvocation(node) || is_Attribute(node)));
+}
+
+export function assertPathAtNode(name: string, node: Node, ...ctx: any[]) {
+	__DEV__: if (getNode() !== node)
+		exit(`Attempted to call ${name}() in wrong prettier path context`, { asserted: node, actual: getNode() }, ...ctx);
+}
+
+export function f(...args: [strings: TemplateStringsArray, ...values: Doc[]]) {
+	let cancel = false;
+	const res = map_tagged_template(args, (doc) => {
+		cancel ||= !doc || (is_array(doc) && doc.length === 0);
+		return doc;
+	});
+	return cancel ? "" : res;
+}
+
+export function sg_single(s: TemplateStringsArray, v_0: Doc) {
+	return group([s[0], indent([softline, v_0]), softline, s[1]]);
+}
+export function sg_duo(s: TemplateStringsArray, v_0: Doc, v_1: Doc) {
+	return group([s[0], indent([softline, v_0, s[1], line, v_1]), softline, s[2]]);
+}
+
+let ctx: {
+	path: AstPath;
+	options: CustomOptions;
+	print: (path?: AstPath | string | [] | undefined, args?: any) => Doc;
+	args: any;
+};
+
+export const getNode = () => ctx.path.stack[ctx.path.stack.length - 1] as Node;
+export const stackIncludes = (x: Node | string | number) => ctx.path.stack.includes(x);
+export const getContext = () => ctx;
+export const getOptions = () => ctx.options;
+export const getProgram = () => ctx.options.rsParsedFile.program;
+export const getAllComments = () => ctx.options[Symbol_comments];
+export const getParentNode = (child?: Node) => {
+	__DEV__: if (child) assertPathAtNode("getParentNode", child);
+	return ctx.path.getParentNode();
+};
+export const getGrandParentNode = () => ctx.path.getParentNode(1) as Node;
+export const getPrintFn = <T extends Node>(forNode?: T | undefined): print<T> => {
+	__DEV__: if (forNode) assertPathAtNode("getPrintFn", forNode);
+	return print as print<T>;
+};
+
+const get = (property: keyof any) => getNode()[property];
+const has = (property: keyof any) => !!get(property);
+
+export function pathCall<T extends Node, K extends keyof NodeProps<T> & keyof T, R>(node: T, key: K, fn: (child: T[K]) => R): R {
+	return ctx.path.call(() => fn(getNode() as any), key as any);
+}
+
+export function pathCallEach<T extends Node, K extends AK<T>>(
+	node: T,
+	key: K, // @ts-expect-error
+	fn: (child: NonNullable<T[K]>[number], index: number) => void
+) {
+	__DEV__: assertPathAtNode("", node); // @ts-expect-error
+	ctx.path.each((_, i) => fn(getNode() as any, i), key);
+}
+
+export function pathCallAtParent<T extends Node, R>(parent: T, fn: (parent: T) => R): R {
+	return ctx.path.callParent(() => {
+		__DEV__: assertPathAtNode("pathCallParent", parent);
+		return fn(parent);
+	});
+}
+export function pathCallParentOf<T extends Node, R>(child: Node, fn: (parent: T) => R): R {
+	__DEV__: assertPathAtNode("pathCallParentOf", child);
+	return ctx.path.callParent((p) => fn(getNode() as any));
+}
+
+export function pathCallTopMostIfBlockExpression<R>(node: IfBlockExpression, fn: (node: IfBlockExpression) => R): R {
+	const parent = getParentNode(node)!;
+	return is_ElseBlock(node, parent) ? pathCallAtParent(parent, (parent) => pathCallTopMostIfBlockExpression(parent, fn)) : fn(node);
+}
+
+function print(property?: any, args?: any): Doc | Doc[] {
+	if (!property) return ctx.print(undefined!, args);
+	if (Array.isArray(property)) return ctx.print(property as any, args);
+	const value = get(property);
+	return !!value ? (Array.isArray(value) ? ctx.path.map(ctx.print, property) : ctx.print(property, args)) : "";
+}
+
+namespace print {
+	export function b(property: string, res = `${property} `): Doc {
+		return has(property) ? res : "";
+	}
+	export function map(property: string, mapItem?: MapFn<any, any>): Doc[] {
+		return !has(property) ? [] : ctx.path.map(mapItem ? (p, i, a) => mapItem(a[i], i, a) : () => ctx.print(), property);
+	}
+	export function join(property: string, sep: SepFn<any, any> | Doc, trailingSep: TrailingSepFn<any, any> | Doc = ""): Doc[] {
+		return map_join(property, () => ctx.print(), sep, trailingSep);
+	}
+	export function map_join(
+		property: string,
+		mapFn: MapFn<any, any>,
+		sep: SepFn<any, any> | Doc,
+		sepTrailing: TrailingSepFn<any, any> | Doc = ""
+	) {
+		const sepFn = typeof sep === "function" ? sep : () => sep;
+		return map(property, (v, i, a) => [
+			mapFn(v, i, a),
+			iLast(i, a as any)
+				? typeof sepTrailing === "function"
+					? sepTrailing(v)
+					: sepTrailing
+				: sepFn(v, a[i + 1], i === 0 ? undefined : a[i - 1]),
+		]);
+	}
+}
+
+// prettier-ignore
+type SepFn<T extends Node = Node, K extends AK<T> = AK<T>> = <A extends AV<T, K>>(item: A[number], next_item: A[number], prev_item: A[number] | undefined) => Doc;
+type MapFn<T extends Node = Node, K extends AK<T> = AK<T>> = <A extends AV<T, K>>(item: A[number], index: number, arr: A) => Doc;
+type TrailingSepFn<T extends Node = Node, K extends AK<T> = AK<T>> = <A extends AV<T, K>>(item: A[number]) => Doc;
+type AV<T extends Node, K extends keyof T> = Extract<NonNullable<T[K]>, ReadonlyArray<unknown>>;
+type AK<T extends Node> = keyof ArrayProps<T> & keyof T;
+// type AK<T extends Node> = keyof PickProps<T, {nodeType:number}|{nodeType:number}[]> & keyof T;
+
+export interface print<T extends Node> {
+	(property?: [], args?: any): Doc;
+	(property?: [AK<T>, number], args?: any): Doc;
+	(property?: AK<T>, args?: any): Doc[];
+	// (property?: T extends {rules:{nodeType:number}|{nodeType:number}[]} ? "rules" : never, args?: any): Doc[];
+	(property?: keyof NodeProps<T> & keyof T, args?: any): Doc;
+	b(property: keyof BoolProps<T>, res?: string): Doc;
+	map<K extends AK<T>>(property: K & keyof ArrayProps<T>, mapFn?: MapFn<T, K>): Doc[];
+	join<K extends AK<T>>(property: K, sep: SepFn<T, K> | Doc, trailingSep?: TrailingSepFn<T, K> | Doc): Doc[];
+	map_join<K extends AK<T>>(property: K, mapFn: MapFn<T, K>, sep: SepFn<T, K> | Doc, trailingSep?: TrailingSepFn<T, K> | Doc): Doc[];
+}
+
+function genericPrint() {
+	return withCheckContext(() => {
+		const node = getNode();
+		__DEV__: assert(node.nodeType in printer);
+
+		let printed: Doc = hasPrettierIgnore(node) //
+			? node.loc.getOwnText()
+			: printer[node.nodeType]!(print as any, node as never);
+
+		const inner_parens = needsInnerParens(node);
+
+		if (inner_parens) {
+			printed = group(["(", printed, ")"]);
+		}
+
+		if (hasAttributes(node)) {
+			const print_above = shouldPrintOuterAttributesAbove(node); /*  || node.attributes.length > 1 */
+			printed = [
+				...print.join(
+					"attributes",
+					(attr) =>
+						print_above
+							? maybeEmptyLine(attr)
+							: is_LineCommentNode(attr) || (is_BlockCommentNode(attr) && hasBreaklineAfter(attr))
+							? hardline
+							: " ",
+					(attr) =>
+						print_above && is_DocCommentAttribute(attr)
+							? maybeEmptyLine(attr)
+							: print_above || is_LineCommentNode(attr) || (is_BlockCommentNode(attr) && hasBreaklineAfter(attr))
+							? hardline
+							: " "
+				),
+				printed,
+			];
+		}
+
+		printed = withComments(
+			node,
+			printed,
+			hasPrettierIgnore(node) || ((is_Attribute(node) || is_MacroInvocation(node)) && !isTransformed(node))
+				? escapeComments(0, (comment) => node.loc.ownContains(comment))
+				: is_MacroRule(node)
+				? escapeComments(0, (comment) => node.transform.loc.contains(comment))
+				: is_UnionPattern(getParentNode() ?? ({ nodeType: 0 } as any))
+				? new Set(getComments(node, CF.Leading | CF.Trailing, (comment) => !isDangling(comment)))
+				: undefined
+		);
+
+		if (!inner_parens && needsOuterSoftbreakParens(node)) {
+			printed = [group(["(", indent([softline, printed]), softline, ")"])];
+		}
+
+		return printed;
+	});
+
+	function hasPrettierIgnore(node: Node) {
+		return (
+			(node as any).prettierIgnore ||
+			hasComment(node, CF.PrettierIgnore) ||
+			(hasAttributes(node) && node.attributes.some(isPrettierIgnoreAttribute))
+		);
+	}
+}
+
+export function canAttachComment(n: Node) {
+	return !is_Comment(n) && !isNoopExpressionStatement(n) && !is_MissingNode(n) && !is_PunctuationToken(n);
+}
+
+export const plugin: Plugin<Node> = {
+	languages: [
+		{
+			name: "Rust",
+			aliases: ["rs"],
+			parsers: ["jinx-rust"],
+			extensions: [".rs", ".rs.in"],
+			linguistLanguageId: 327,
+			vscodeLanguageIds: ["rust"],
+			tmScope: "source.rust",
+			aceMode: "rust",
+			codemirrorMode: "rust",
+			codemirrorMimeType: "text/x-rustsrc",
+		},
+	],
+	parsers: {
+		"jinx-rust": {
+			astFormat: "jinx-rust",
+			locStart: start,
+			locEnd: end,
+			parse(code: string, options: ParserOptions<Node> & Partial<CustomOptions>) {
+				const customOptions = options as CustomOptions;
+				ctx = { options: customOptions } as any;
+
+				customOptions.rsParsedFile = rs.parseFile((customOptions.originalText = code), { filepath: customOptions.filepath });
+
+				customOptions.actuallyMethodNodes = new WeakSet();
+				customOptions.danglingAttributes = [];
+				customOptions.comments = [];
+
+				transform_ast(customOptions);
+
+				const comments: AttributeOrComment[] = [];
+				insertNodes(comments, customOptions.comments);
+				insertNodes(comments, customOptions.danglingAttributes);
+
+				// @ts-expect-error
+				customOptions.rsParsedFile.program.comments = comments;
+
+				customOptions.commentSpans = new Map(comments.map((n) => [start(n), end(n)]));
+
+				return customOptions.rsParsedFile.program;
+			},
+		},
+	},
+	printers: {
+		"jinx-rust": {
+			preprocess: (node: Node) => (node as Program).loc?.src || node,
+			print(path, options, print, args) {
+				if (path.stack.length === 1) {
+					__DEV__: Narrow<CustomOptions>(options);
+					ctx = { path, options, print: print as any, args };
+					try {
+						const printed = genericPrint();
+						__DEV__: devEndCheck(printed);
+						return printed;
+					} finally {
+						ctx = undefined!;
+					}
+				} else if (args || ctx.args) {
+					const prev_args = ctx.args;
+					try {
+						ctx.args = args;
+						return genericPrint();
+					} finally {
+						ctx.args = prev_args;
+					}
+				} else {
+					return genericPrint();
+				}
+			},
+			hasPrettierIgnore: () => false,
+			willPrintOwnComments: () => true,
+			isBlockComment: (node: Node): boolean => {
+				return is_AttributeOrComment(node) && is_BlockCommentKind(node as any);
+			},
+			canAttachComment: canAttachComment,
+			getCommentChildNodes: getCommentChildNodes,
+			printComment: genericPrint,
+			handleComments: {
+				// @ts-expect-error
+				avoidAstMutation: true,
+				ownLine: handleOwnLineComment,
+				endOfLine: handleEndOfLineComment,
+				remaining: handleRemainingComment,
+			},
+		},
+	},
+	options: {},
+	defaultOptions: {
+		// default prettier (2)  -> rustfmt (4)
+		tabWidth: 4,
+		// default prettier (80) -> rustfmt (100)
+		printWidth: 100,
+	},
+};
+
+function devEndCheck(printed: Doc) {
+	let first = false;
+	const comments = getAllComments();
+	each(comments, (comment, index) => {
+		if (!comment.printed) {
+			if (!first) (first = true), console.log(color.red(`Unprinted comments:`));
+			const len = 40;
+			const msg =
+				color.magenta(
+					(comment.marker ? `Dangling "${comment.marker}" ` : "") +
+						(is_Attribute(comment) ? "Attribute " : is_DocCommentAttribute(comment) ? "DocCommentAttribute" : "Comment") +
+						` ${index}/${comments.length}` +
+						color.yellow(` ${print_string(comment.loc.sliceText(0, len))}${comment.loc.len() > len ? " ..." : ""}`)
+				) + color.grey(`\n    at ${comment.loc.url()}`);
+			if (globalThis.TESTS_FORMAT_DEV) exit(msg);
+			else console.log(msg);
+			setDidPrintComment(comment);
+		}
+	});
+}

frontend/src/utils/prettier/plugins/rust/format/printer.ts

@@ -0,0 +1,719 @@
+import { DelimKind, Node, NodeType, NTMap } from "jinx-rust";
+import {
+	getDelimChars,
+	hasSuffix,
+	is_ArrayOrTupleLiteral,
+	is_BlockExpression,
+	is_ClosureFunctionExpression,
+	is_Identifier,
+	is_IfBlockExpression,
+	is_LiteralNumberLike,
+	is_StructLiteral,
+	start,
+} from "jinx-rust/utils";
+import {
+	BlockLikeMacroInvocation,
+	CallLikeMacroInvocation,
+	is_BlockLikeMacroInvocation,
+	is_CallLikeMacroInvocation,
+	isTransformed,
+} from "../transform";
+import { exit } from "../utils/common";
+import { hasComment, print_comment } from "./comments";
+import { isSimpleType } from "./complexity";
+import {
+	adjustClause,
+	parenthesize_if_break,
+	printAnnotatedPattern,
+	printArrayLike,
+	printArrowFunction,
+	printAssignment,
+	printBinaryishExpression,
+	printBlockBody,
+	printBodyOrCases,
+	printCallArguments,
+	printCallExpression,
+	printCondition,
+	printDanglingCommentsForInline,
+	printDeclarationTypeBounds,
+	printEnumBody,
+	printFlowControlExpression,
+	printGenerics_x_whereBounds,
+	printIfBlock,
+	printIfBlockCondition,
+	printImplTraitForType,
+	printLtBounds,
+	printLtParameters,
+	printMacroRules,
+	printMaybeBlockBody,
+	printMemberExpression,
+	printNumber,
+	printObject,
+	printParametersAndReturnType,
+	printRuleMatch,
+	printRuleTransform,
+	printTypeAnnotation,
+	printTypeArguments,
+	printTypeBounds,
+	printUnaryExpression,
+	printUnionPattern,
+} from "./core";
+import { DCM, Doc, group, hardline, ifBreak, indent, join, line, softline, willBreak } from "./external";
+import { f, getOptions, getParentNode, pathCall, sg_duo, sg_single, type print } from "./plugin";
+import { needsParens, stmtNeedsSemi } from "./styling";
+
+type nPrint<T extends Node> = (print: print<T>, node: T) => Doc | never;
+
+export const printer: { [K in NodeType]: nPrint<Extract<NTMap[K], Node>> } = {
+	[NodeType.MissingNode](print, node) {
+		return "";
+	},
+	[NodeType.SourceFile](print, node) {
+		return [
+			print.b("UTF8BOM", "\uFEFF"), //
+			print("shebang"),
+			print("program"),
+		];
+	},
+	[NodeType.Shebang](print, node) {
+		return [`#!${node.value}`, hardline];
+	},
+	[NodeType.Program](print, node) {
+		return printBodyOrCases(print, node);
+	},
+	[NodeType.Snippet](print, node) {
+		exit.never();
+	},
+	[NodeType.Identifier](print, node) {
+		return node.name;
+	},
+	[NodeType.Index](print, node) {
+		return node.name;
+	},
+	[NodeType.LbIdentifier](print, node) {
+		return node.name;
+	},
+	[NodeType.McIdentifier](print, node) {
+		return node.name;
+	},
+	[NodeType.LtIdentifier](print, node) {
+		return node.name;
+	},
+	[NodeType.PunctuationToken](print, node) {
+		return node.token;
+	},
+	[NodeType.DelimGroup](print, node) {
+		return node.loc.getOwnText();
+	},
+	[NodeType.Literal](print, node) {
+		let { value } = node;
+		if (is_LiteralNumberLike(node)) value = printNumber(value);
+		return hasSuffix(node) ? [value, print("suffix")] : value;
+	},
+	[NodeType.ItemPath](print, node) {
+		return [print("namespace"), "::", print("segment")];
+	},
+	[NodeType.ExpressionPath](print, node) {
+		return [print("namespace"), "::", print("segment")];
+	},
+	[NodeType.TypePath](print, node) {
+		return [print("namespace"), "::", print("segment")];
+	},
+	[NodeType.Comment](print, node) {
+		return print_comment(node);
+	},
+	[NodeType.DocCommentAttribute](print, node) {
+		return print_comment(node);
+	},
+	[NodeType.Attribute](print, node) {
+		return [
+			node.inner ? "#![" : "#[",
+			isTransformed(node)
+				? [print("segments"), printDanglingCommentsForInline(node)] //
+				: node.segments.loc.sliceText(1, -1).trim(),
+			"]",
+		];
+	},
+	[NodeType.MacroInvocation](print, node) {
+		const hasCurlyBrackets = node.segments.dk === DelimKind["{}"];
+		const delim = getDelimChars(node.segments);
+		if (node.segments.length === 0) {
+			return [print("callee"), "!", hasCurlyBrackets ? " " : "", delim.left, printDanglingCommentsForInline(node), delim.right];
+		}
+		if (isTransformed(node)) {
+			if (is_CallLikeMacroInvocation(node)) {
+				return [print("callee"), "!", printCallArguments(print as print<CallLikeMacroInvocation>, node)];
+			}
+			if (is_BlockLikeMacroInvocation(node)) {
+				return [print("callee"), "!", " ", printBlockBody(print as print<BlockLikeMacroInvocation>, node)];
+			}
+		}
+		let content = node.segments.loc.sliceText(1, -1);
+		if (content.trim().length === 0) {
+			content = "";
+		} else if (!content.includes("\n")) {
+			content = content.trim();
+			if (hasCurlyBrackets) content = " " + content + " ";
+		}
+		return [print("callee"), "!", hasCurlyBrackets ? " " : "", delim.left, content, delim.right];
+	},
+	[NodeType.MacroRulesDeclaration](print, node) {
+		return ["macro_rules! ", print("id"), printMacroRules(print, node)];
+	},
+	[NodeType.MacroRuleDeclaration](print, node) {
+		return [printRuleMatch(print, node), " => ", printRuleTransform(print, node), ";"];
+	},
+	[NodeType.MacroDeclaration](print, node) {
+		return [print("pub"), "macro ", print("id"), printMacroRules(print, node)];
+	},
+	[NodeType.MacroInlineRuleDeclaration](print, node) {
+		return [printRuleMatch(print, node), " ", printRuleTransform(print, node)];
+	},
+	[NodeType.MacroGroup](print, node) {
+		return node.loc.getOwnText();
+	},
+	[NodeType.MacroParameterDeclaration](print, node) {
+		return [print("id"), ":", print("ty")];
+	},
+	[NodeType.PubSpecifier](print, node) {
+		if (!node.location) return "pub ";
+		if (is_Identifier(node.location)) {
+			switch (node.location.name) {
+				case "crate":
+					if (start(node) === start(node.location)) {
+						return "crate ";
+					} else {
+						return ["pub(", print("location"), ") "];
+					}
+				case "self":
+				case "super":
+					return ["pub(", print("location"), ") "];
+			}
+		}
+		return ["pub(in ", print("location"), ") "];
+	},
+	[NodeType.ExternSpecifier](print, node) {
+		return ["extern ", f`${print("abi")} `];
+	},
+	[NodeType.ExpressionStatement](print, node) {
+		return [print("expression"), stmtNeedsSemi(node) ? ";" : ""];
+	},
+	[NodeType.UseStatement](print, node) {
+		return [print("pub"), "use ", print("import"), ";"];
+	},
+	[NodeType.DestructuredImport](print, node) {
+		if (node.specifiers.length === 0) return [print("source"), "::{", printDanglingCommentsForInline(node, DCM["specifiers"]), "}"];
+		let space = true;
+		__DEV__: if (globalThis.TESTS_FORMAT_DEV) space = false;
+		return [
+			print("source"),
+			group([
+				"::{",
+				indent([space ? line : softline, join([",", line], print("specifiers")), ifBreak(",")]),
+				space ? line : softline,
+				"}",
+			]),
+		];
+	},
+	[NodeType.AmbientImport](print, node) {
+		return f`${print("source")}::*` || "*";
+	},
+	[NodeType.AnonymousImport](print, node) {
+		return [print("source"), " as ", "_"];
+	},
+	[NodeType.NamedImport](print, node) {
+		return [print("source"), f` as ${print("local")}`];
+	},
+	[NodeType.ExternCrateStatement](print, node) {
+		return [print("pub"), "extern crate ", print("import"), ";"];
+	},
+	[NodeType.TypeAliasDeclaration](print, node) {
+		return [
+			print("pub"),
+			"type",
+			printAssignment(
+				printGenerics_x_whereBounds(print, node, printDeclarationTypeBounds(print, node, ":")), //
+				" =",
+				"typeExpression"
+			),
+			";",
+		];
+	},
+	[NodeType.LetVariableDeclaration](print, node) {
+		return [
+			"let ",
+			printAssignment(
+				printAnnotatedPattern(print, node), //
+				" =",
+				"expression"
+			),
+			f` else ${print("else")}`,
+			";",
+		];
+	},
+	[NodeType.ConstVariableDeclaration](print, node) {
+		return [
+			print("pub"),
+			"const ",
+			printAssignment(
+				printAnnotatedPattern(print, node), //
+				" =",
+				"expression"
+			),
+			";",
+		];
+	},
+	[NodeType.StaticVariableDeclaration](print, node) {
+		return [
+			print("pub"),
+			"static ",
+			printAssignment(
+				printAnnotatedPattern(print, node), //
+				" =",
+				"expression"
+			),
+			";",
+		];
+	},
+	[NodeType.ModuleDeclaration](print, node) {
+		return [
+			print("pub"), //
+			print.b("unsafe"),
+			"mod ",
+			print("id"),
+			printMaybeBlockBody(print, node),
+		];
+	},
+	[NodeType.ExternBlockDeclaration](print, node) {
+		return [
+			print("pub"), //
+			print.b("unsafe"),
+			"extern ",
+			f`${print("abi")} `,
+			printBlockBody(print, node),
+		];
+	},
+	[NodeType.FunctionDeclaration](print, node) {
+		return [
+			print("pub"),
+			print.b("const"),
+			print.b("async"),
+			print.b("unsafe"),
+			print("extern"),
+			"fn",
+			printGenerics_x_whereBounds(print, node, printParametersAndReturnType(node)),
+			printMaybeBlockBody(print, node),
+		];
+	},
+	[NodeType.FunctionSelfParameterDeclaration](print, node) {
+		return group([print.b("ref", "&"), f`${print("lt")} `, print.b("mut"), "self", printTypeAnnotation(print, node)]);
+	},
+	[NodeType.FunctionParameterDeclaration](print, node) {
+		return group(printAnnotatedPattern(print, node));
+	},
+	[NodeType.FunctionSpread](print, node) {
+		return "...";
+	},
+	[NodeType.StructDeclaration](print, node) {
+		return [print("pub"), "struct", printGenerics_x_whereBounds(print, node, ""), printObject(print, node)];
+	},
+	[NodeType.StructPropertyDeclaration](print, node) {
+		return [print("pub"), print("id"), printTypeAnnotation(print, node)];
+	},
+	[NodeType.TupleStructDeclaration](print, node) {
+		return [print("pub"), "struct", printGenerics_x_whereBounds(print, node, printArrayLike(print, node)), ";"];
+	},
+	[NodeType.TupleStructItemDeclaration](print, node) {
+		return [print("pub"), print("typeAnnotation")];
+	},
+	[NodeType.UnionDeclaration](print, node) {
+		return [print("pub"), "union", printGenerics_x_whereBounds(print, node, ""), printObject(print, node)];
+	},
+	[NodeType.EnumDeclaration](print, node) {
+		return [print("pub"), "enum", printGenerics_x_whereBounds(print, node, ""), printEnumBody(print, node)];
+	},
+	[NodeType.EnumMemberDeclaration](print, node) {
+		return [
+			print("pub"),
+			printAssignment(
+				print("id"), //
+				" =",
+				"value"
+			),
+		];
+	},
+	[NodeType.EnumMemberTupleDeclaration](print, node) {
+		return [
+			print("pub"),
+			printAssignment(
+				[print("id"), printArrayLike(print, node)], //
+				" =",
+				"value"
+			),
+		];
+	},
+	[NodeType.EnumMemberStructDeclaration](print, node) {
+		return [
+			print("pub"),
+			printAssignment(
+				[print("id"), printObject(print, node)], //
+				" =",
+				"value"
+			),
+		];
+	},
+	[NodeType.TraitDeclaration](print, node) {
+		return [
+			print("pub"),
+			print.b("unsafe"),
+			"trait",
+			printGenerics_x_whereBounds(print, node, printDeclarationTypeBounds(print, node, ":")),
+			adjustClause(node, printBlockBody(print, node)),
+		];
+	},
+	[NodeType.AutoTraitDeclaration](print, node) {
+		return [
+			print("pub"),
+			print.b("unsafe"),
+			"auto trait ",
+			print("id"),
+			" ",
+			printBlockBody(print, node as any), // see "transform.ts"
+		];
+	},
+	[NodeType.TraitAliasDeclaration](print, node) {
+		return [
+			print("pub"),
+			print.b("unsafe"),
+			"trait",
+			printGenerics_x_whereBounds(print, node, printDeclarationTypeBounds(print, node, " =")),
+			";",
+		];
+	},
+	[NodeType.ImplDeclaration](print, node) {
+		return [
+			print("pub"),
+			print.b("unsafe"),
+			"impl",
+			printGenerics_x_whereBounds(print, node, [print.b("const"), printImplTraitForType(print, node)]),
+			adjustClause(node, printBlockBody(print, node)),
+		];
+	},
+	[NodeType.NegativeImplDeclaration](print, node) {
+		return [
+			print("pub"),
+			"impl",
+			printGenerics_x_whereBounds(print, node, ["!", printImplTraitForType(print, node)]),
+			" ",
+			printBlockBody(print, node as any), // see "transform.ts"
+		];
+	},
+	[NodeType.ExpressionTypeSelector](print, node) {
+		return group(["<", print("typeTarget"), f` as ${print("typeExpression")}`, ">"]);
+	},
+	[NodeType.ExpressionTypeCast](print, node) {
+		return [print("typeCallee"), f`::${printTypeArguments(print, node)}`];
+	},
+	[NodeType.ExpressionAsTypeCast](print, node) {
+		return [print("expression"), " as ", print("typeExpression")];
+	},
+	[NodeType.ReturnExpression](print, node) {
+		return ["return", printFlowControlExpression(print, node)];
+	},
+	[NodeType.BreakExpression](print, node) {
+		return ["break", f` ${print("label")}`, printFlowControlExpression(print, node)];
+	},
+	[NodeType.ContinueExpression](print, node) {
+		return ["continue", f` ${print("label")}`];
+	},
+	[NodeType.YieldExpression](print, node) {
+		return ["yield", printFlowControlExpression(print, node)];
+	},
+	[NodeType.RangeLiteral](print, node) {
+		return [print("lower"), "..", print.b("last", "="), print("upper")];
+	},
+	[NodeType.CallExpression](print, node) {
+		return printCallExpression(print, node);
+	},
+	[NodeType.MemberExpression](print, node) {
+		return printMemberExpression(print, node);
+	},
+	[NodeType.AwaitExpression](print, node) {
+		return [print("expression"), ".await"];
+	},
+	[NodeType.UnwrapExpression](print, node) {
+		return [print("expression"), "?"];
+	},
+	[NodeType.ParenthesizedExpression](print, node) {
+		exit.never();
+		const shouldHug = !hasComment(node.expression) && (is_ArrayOrTupleLiteral(node.expression) || is_StructLiteral(node.expression));
+		if (shouldHug) return ["(", print("expression"), ")"];
+		return group(["(", indent([softline, print("expression")]), softline, ")"]);
+	},
+	[NodeType.MinusExpression](print, node) {
+		return printUnaryExpression("-", node);
+	},
+	[NodeType.NotExpression](print, node) {
+		return printUnaryExpression("!", node);
+	},
+	[NodeType.OrExpression](print, node) {
+		return printBinaryishExpression(print, node);
+	},
+	[NodeType.AndExpression](print, node) {
+		return printBinaryishExpression(print, node);
+	},
+	[NodeType.ReassignmentExpression](print, node) {
+		return printAssignment(print("left"), " =", "right");
+	},
+	[NodeType.UnassignedExpression](print, node) {
+		return "_";
+	},
+	[NodeType.OperationExpression](print, node) {
+		return printBinaryishExpression(print, node);
+	},
+	[NodeType.ReassignmentOperationExpression](print, node) {
+		return printAssignment(print("left"), " " + node.kind, "right");
+	},
+	[NodeType.ComparisonExpression](print, node) {
+		return printBinaryishExpression(print, node);
+	},
+	[NodeType.LetScrutinee](print, node) {
+		return ["let ", printAssignment(print("pattern"), " =", "expression")];
+	},
+	[NodeType.ClosureFunctionExpression](print, node) {
+		return printArrowFunction(print, node);
+	},
+	[NodeType.ClosureFunctionParameterDeclaration](print, node) {
+		return group(printAnnotatedPattern(print, node));
+	},
+	[NodeType.BlockExpression](print, node) {
+		return [
+			f`${print("label")}: `,
+			print.b("const"),
+			print.b("async"),
+			print.b("move"),
+			print.b("unsafe"),
+			printBlockBody(print, node),
+		];
+	},
+	[NodeType.LoopBlockExpression](print, node) {
+		return [f`${print("label")}: `, "loop ", printBlockBody(print, node)];
+	},
+	[NodeType.WhileBlockExpression](print, node) {
+		return [f`${print("label")}: `, "while ", printCondition(print, node), printBlockBody(print, node)];
+	},
+	[NodeType.ForInBlockExpression](print, node) {
+		return [f`${print("label")}: `, "for ", print("pattern"), " in ", print("expression"), " ", printBlockBody(print, node)];
+	},
+	[NodeType.IfBlockExpression](print, node) {
+		return [f`${print("label")}: `, printIfBlock(print, node)];
+	},
+	[NodeType.TryBlockExpression](print, node) {
+		return [f`${print("label")}: `, "try ", printBlockBody(print, node)];
+	},
+	[NodeType.MatchExpression](print, node) {
+		const id = Symbol("match");
+		const expr = print("expression");
+		const needs_parens = pathCall(node, "expression", needsParens);
+
+		let printed: Doc = [
+			f`${print("label")}: `,
+			"match ",
+			needs_parens ? expr : group([indent([softline, expr]), softline], { id }),
+			needs_parens ? " " : !willBreak(expr) ? ifBreak("", " ", { groupId: id }) : "" /*  ifBreak("", " ", { groupId: id }) */,
+			printBlockBody(print, node),
+		];
+
+		const parent = getParentNode()!;
+		if (is_ClosureFunctionExpression(parent) && parent.expression === node) {
+			printed = parenthesize_if_break([indent([softline, printed]), softline]);
+		}
+		return printed;
+	},
+	[NodeType.MatchExpressionCase](print, node) {
+		return group([
+			group(print("pattern")),
+			" ",
+			printIfBlockCondition(print, node),
+			"=>", //
+			(is_BlockExpression(node.expression) || is_IfBlockExpression(node.expression)) &&
+			!hasComment(node.expression, 0, (comment) => getOptions().danglingAttributes.includes(comment as any))
+				? [" ", print("expression")]
+				: group(indent([line, print("expression")])),
+		]);
+		return printAssignment(
+			[print("pattern"), " ", printIfBlockCondition(print, node)], //
+			"=>",
+			"expression"
+		);
+		return [print("pattern"), " ", printIfBlockCondition(print, node)];
+	},
+	[NodeType.StructLiteral](print, node) {
+		return [print("struct"), printObject(print, node)];
+	},
+	[NodeType.StructLiteralPropertyShorthand](print, node) {
+		return print("value");
+	},
+	[NodeType.StructLiteralProperty](print, node) {
+		return [print("key"), ": ", print("value")];
+	},
+	[NodeType.StructLiteralPropertySpread](print, node) {
+		return ["..", print("expression")];
+	},
+	[NodeType.StructLiteralRestUnassigned](print, node) {
+		return "..";
+	},
+	[NodeType.ArrayLiteral](print, node) {
+		return printArrayLike(print, node);
+	},
+	[NodeType.SizedArrayLiteral](print, node) {
+		return sg_duo`[${print("initExpression")};${print("sizeExpression")}]`;
+	},
+	[NodeType.TupleLiteral](print, node) {
+		return printArrayLike(print, node);
+	},
+	[NodeType.ReferenceExpression](print, node) {
+		return printUnaryExpression(["&", print.b("mut")], node);
+	},
+	[NodeType.RawReferenceExpression](print, node) {
+		return printUnaryExpression(`&raw ${node.kind} `, node);
+	},
+	[NodeType.DereferenceExpression](print, node) {
+		return printUnaryExpression("*", node);
+	},
+	[NodeType.BoxExpression](print, node) {
+		return printUnaryExpression("box ", node);
+	},
+	[NodeType.UnionPattern](print, node) {
+		return printUnionPattern(print, node);
+	},
+	[NodeType.ParenthesizedPattern](print, node) {
+		exit.never();
+		return sg_single`(${print("pattern")})`;
+	},
+	[NodeType.RestPattern](print, node) {
+		return "..";
+	},
+	[NodeType.WildcardPattern](print, node) {
+		return "_";
+	},
+	[NodeType.PatternVariableDeclaration](print, node) {
+		return [print.b("ref"), print.b("mut"), printAssignment(print("id"), " @", "pattern")];
+	},
+	[NodeType.StructPattern](print, node) {
+		return [print("struct"), printObject(print, node)];
+	},
+	[NodeType.StructPatternPropertyDestructured](print, node) {
+		return [print("key"), ": ", print("pattern")];
+	},
+	[NodeType.StructPatternPropertyShorthand](print, node) {
+		return [print.b("box"), print.b("ref"), print.b("mut"), print("id")];
+	},
+	[NodeType.TuplePattern](print, node) {
+		return [print("struct"), printArrayLike(print, node)];
+	},
+	[NodeType.ArrayPattern](print, node) {
+		return printArrayLike(print, node);
+	},
+	[NodeType.ReferencePattern](print, node) {
+		return ["&", print.b("mut"), print("pattern")];
+	},
+	[NodeType.BoxPattern](print, node) {
+		return ["box ", print("pattern")];
+	},
+	[NodeType.MinusPattern](print, node) {
+		return ["-", print("pattern")];
+	},
+	[NodeType.RangePattern](print, node) {
+		return [print("lower"), "..", print.b("last", "="), print("upper")];
+	},
+	[NodeType.TypeCall](print, node) {
+		return [print("typeCallee"), printTypeArguments(print, node)];
+	},
+	[NodeType.TypeCallNamedArgument](print, node) {
+		return printAssignment(print("target"), " =", "typeExpression");
+	},
+	[NodeType.TypeCallNamedBound](print, node) {
+		return [print("typeTarget"), printTypeBounds(":", print, node)];
+	},
+	[NodeType.LtElided](print, node) {
+		return "'_";
+	},
+	[NodeType.LtStatic](print, node) {
+		return "'static";
+	},
+	[NodeType.TypeNever](print, node) {
+		return "!";
+	},
+	[NodeType.TypeInferred](print, node) {
+		return "_";
+	},
+	[NodeType.GenericTypeParameterDeclaration](print, node) {
+		return printAssignment(
+			[print("id"), printTypeBounds(":", print, node)], //
+			" =",
+			"typeDefault"
+		);
+	},
+	[NodeType.ConstTypeParameterDeclaration](print, node) {
+		return [
+			"const ",
+			printAssignment(
+				[print("id"), printTypeAnnotation(print, node)], //
+				" =",
+				"typeDefault"
+			),
+		];
+	},
+	[NodeType.GenericLtParameterDeclaration](print, node) {
+		return [print("id"), printLtBounds(":", print, node)];
+	},
+	[NodeType.WhereTypeBoundDeclaration](print, node) {
+		return [printLtParameters(print, node), print("typeTarget"), printTypeBounds(":", print, node)];
+	},
+	[NodeType.WhereLtBoundDeclaration](print, node) {
+		return [print("ltTarget"), printLtBounds(":", print, node)];
+	},
+	[NodeType.TypeTraitBound](print, node) {
+		return [print.b("maybeConst", "~const "), print.b("optional", "?"), printLtParameters(print, node), print("typeExpression")];
+	},
+	[NodeType.TypeDynBounds](print, node) {
+		return printTypeBounds("dyn", print, node);
+	},
+	[NodeType.TypeImplBounds](print, node) {
+		return printTypeBounds("impl", print, node);
+	},
+	[NodeType.TypeFnPointer](print, node) {
+		return [printLtParameters(print, node), print.b("unsafe"), print("extern"), "fn", printParametersAndReturnType(node)];
+	},
+	[NodeType.TypeFnPointerParameter](print, node) {
+		return [f`${print("id")}: `, print("typeAnnotation")];
+	},
+	[NodeType.TypeFunction](print, node) {
+		return [print("callee"), printParametersAndReturnType(node)];
+	},
+	[NodeType.TypeTuple](print, node) {
+		return printArrayLike(print, node);
+	},
+	[NodeType.TypeSizedArray](print, node) {
+		return sg_duo`[${print("typeExpression")};${print("sizeExpression")}]`;
+		if (isSimpleType(node)) return ["[", print("typeExpression"), "; ", print("sizeExpression"), "]"];
+	},
+	[NodeType.TypeSlice](print, node) {
+		if (isSimpleType(node)) return ["[", print("typeExpression"), "]"];
+		return sg_single`[${print("typeExpression")}]`;
+	},
+	[NodeType.TypeReference](print, node) {
+		return ["&", f`${print("lt")} `, print.b("mut"), print("typeExpression")];
+	},
+	[NodeType.TypeDereferenceConst](print, node) {
+		return ["*const ", print("typeExpression")];
+	},
+	[NodeType.TypeDereferenceMut](print, node) {
+		return ["*mut ", print("typeExpression")];
+	},
+	[NodeType.TypeParenthesized](print, node) {
+		exit.never();
+		return sg_single`(${print("typeExpression")})`;
+	},
+};

frontend/src/utils/prettier/plugins/rust/format/styling.ts

@@ -0,0 +1,645 @@
+import {
+	ClosureFunctionExpression,
+	ComparisonExpression,
+	ConditionExpression,
+	EnumDeclaration,
+	EnumMemberStructDeclaration,
+	ExpressionAsTypeCast,
+	ExpressionNode,
+	ExpressionStatement,
+	ExpressionWithBody,
+	LeftRightExpression,
+	LogicalExpression,
+	MacroDeclaration,
+	MacroRulesDeclaration,
+	MissingNode,
+	Node,
+	NodeType,
+	NodeWithBody,
+	NodeWithBodyOrCases,
+	OperationExpression,
+	PRCD,
+	StructDeclaration,
+	StructLiteral,
+	StructPattern,
+	TK,
+	UnionDeclaration,
+} from "jinx-rust";
+import {
+	can_have_OuterAttributes,
+	getAstPath,
+	getPrecedence,
+	hasAttributes,
+	hasBody,
+	hasCondition,
+	hasItems,
+	hasLetScrutineeCondition,
+	hasOuterAttributes,
+	hasProperties,
+	is_Attribute,
+	is_AttributeOrDocComment,
+	is_AwaitExpression,
+	is_BitwiseOperator,
+	is_CallExpression,
+	is_ClosureFunctionExpression,
+	is_ComparisonExpression,
+	is_DocCommentAttribute,
+	is_ElseBlock,
+	is_EnumMemberDeclaration,
+	is_EqualityOperator,
+	is_ExpressionAsTypeCast,
+	is_ExpressionStatement,
+	is_ExpressionWithBody,
+	is_ExpressionWithBodyOrCases,
+	is_ExpressionWithBodyOrCases_or_BlockLikeMacroInvocation,
+	is_FlowControlExpression,
+	is_FlowControlMaybeValueExpression,
+	is_ForInBlockExpression,
+	is_Identifier,
+	is_IfBlockExpression,
+	is_ImplicitReturnAbleNode,
+	is_LeftRightExpression,
+	is_LetScrutinee,
+	is_Literal,
+	is_LiteralNumberLike,
+	is_LogicalExpression,
+	is_LoopBlockExpression,
+	is_MatchExpression,
+	is_MatchExpressionCase,
+	is_MemberExpression,
+	is_NodeWithBodyNoBody,
+	is_NodeWithMaybePatternNoUnionBody,
+	is_OperationExpression,
+	is_ParenthesizedNode,
+	is_PatternVariableDeclaration,
+	is_PostfixExpression,
+	is_RangeLiteral,
+	is_ReassignmentNode,
+	is_ReturnExpression,
+	is_StatementNode,
+	is_StructLiteral,
+	is_StructLiteralProperty,
+	is_StructPatternProperty,
+	is_StructPropertyDeclaration,
+	is_TypeBoundsStandaloneNode,
+	is_TypeFunctionNode,
+	is_TypeTraitBound,
+	is_UnaryExpression,
+	is_UnaryType,
+	is_UnionPattern,
+	is_WhileBlockExpression,
+	is_YieldExpression,
+	is_bitshiftOperator,
+	is_multiplicativeOperator,
+} from "jinx-rust/utils";
+import { BlockLikeMacroInvocation, is_BlockLikeMacroInvocation, is_CallExpression_or_CallLikeMacroInvocation } from "../transform";
+import { exit, last_of } from "../utils/common";
+import { CF, hasBreaklineAfter, hasComment } from "./comments";
+import { flowControlExpressionNeedsOuterParens } from "./core";
+import { Doc, hardline, softline, willBreak } from "./external";
+import {
+	assertPathAtNode,
+	getContext,
+	getGrandParentNode,
+	getNode,
+	getOptions,
+	getParentNode,
+	getPrintFn,
+	is_printing_macro,
+	pathCallAtParent,
+	pathCallParentOf,
+	stackIncludes,
+} from "./plugin";
+
+export function needsOuterSoftbreakParens(node: Node) {
+	const parent = getParentNode(node);
+
+	if (!parent) return false;
+
+	if (is_ExpressionAsTypeCast(node)) {
+		return precedenceNeedsParens(node, parent);
+	}
+
+	if (
+		is_FlowControlMaybeValueExpression(parent) && //
+		parent.expression === node &&
+		flowControlExpressionNeedsOuterParens(parent)
+	) {
+		return true;
+	}
+	if (
+		is_ExpressionWithBodyOrCases_or_BlockLikeMacroInvocation(node) &&
+		(false ||
+			(is_MemberExpression(parent) && parent.expression === node) ||
+			(is_ExpressionWithBodyOrCases_or_BlockLikeMacroInvocation(parent) && !is_ElseBlock(node, parent)))
+	) {
+		return true;
+	}
+
+	if (is_UnionPattern(node) && is_NodeWithMaybePatternNoUnionBody(parent)) {
+		return true;
+	}
+
+	if (hasComment(node)) {
+		if (is_UnaryExpression(parent)) {
+			return true;
+		}
+
+		if (hasComment(node, CF.Line)) {
+			if (is_ReturnExpression(parent) || (is_YieldExpression(parent) && parent.expression === node)) {
+				return true;
+			}
+		}
+
+		if (
+			hasComment(node, CF.Leading, (comment) => is_Attribute(comment) && !comment.inner) &&
+			!can_have_OuterAttributes(node, parent, true)
+		) {
+			return true;
+		}
+	}
+
+	return false;
+}
+
+export function needsInnerParens(node: Node) {
+	if (needsOuterSoftbreakParens(node)) {
+		return false;
+	}
+
+	const parent = getParentNode(node);
+
+	if (!parent) {
+		return false;
+	}
+
+	if (is_Identifier(node)) {
+		return false;
+	}
+
+	if (is_Literal(node)) {
+		return is_LiteralNumberLike(node) && is_MemberExpression(parent) && node === parent.expression;
+	}
+
+	if (is_CallExpression(parent) && parent.callee === node && is_MemberExpression(node)) {
+		return !getOptions().actuallyMethodNodes.has(node);
+	}
+
+	if (is_ReassignmentNode(node)) {
+		if (is_printing_macro()) {
+			return false;
+		}
+
+		if (is_ClosureFunctionExpression(parent) && node === parent.expression) {
+			return true;
+		}
+
+		if (is_ExpressionStatement(parent)) {
+			return is_StructLiteral(node.left);
+		}
+
+		if (is_ReassignmentNode(parent)) {
+			return false;
+		}
+
+		return true;
+	}
+
+	if (is_ParenthesizedNode(parent)) {
+		return false;
+	}
+
+	if (is_ExpressionStatement(parent)) {
+		return false;
+	}
+
+	if (is_RangeLiteral(node)) {
+		return (
+			is_ExpressionAsTypeCast(parent) ||
+			is_LogicalExpression(parent) ||
+			is_UnaryExpression(parent) ||
+			is_PostfixExpression(parent) ||
+			(is_MemberExpression(parent) && node === parent.expression) ||
+			(is_CallExpression(parent) && node === parent.callee) ||
+			is_OperationExpression(parent) ||
+			is_ComparisonExpression(parent)
+		);
+	}
+
+	if (is_LetScrutinee(parent) && is_LogicalExpression(node) && parent.expression === (node as any)) {
+		return true;
+	}
+
+	if (is_UnaryExpression(node)) {
+		switch (parent.nodeType) {
+			case NodeType.MemberExpression:
+			case NodeType.AwaitExpression:
+				return node === parent.expression;
+			case NodeType.CallExpression:
+				return node === parent.callee;
+			default:
+				return false;
+		}
+	}
+
+	if (is_ExpressionWithBodyOrCases_or_BlockLikeMacroInvocation(node)) {
+		if (is_ExpressionWithBodyOrCases(parent)) {
+			return !is_ElseBlock(node, parent);
+		}
+		if (is_LetScrutinee(parent) && parent.expression === node && is_ExpressionWithBodyOrCases(getGrandParentNode())) {
+			return true;
+		}
+		return (
+			is_ExpressionAsTypeCast(parent) ||
+			is_LogicalExpression(parent) ||
+			is_UnaryExpression(parent) ||
+			is_PostfixExpression(parent) ||
+			(is_MemberExpression(parent) && node === parent.expression) ||
+			(is_CallExpression(parent) && node === parent.callee) ||
+			is_OperationExpression(parent) ||
+			is_ComparisonExpression(parent) ||
+			is_RangeLiteral(parent)
+		);
+	}
+
+	if (is_StructLiteral(node)) {
+		if (is_ExpressionWithBodyOrCases(parent)) {
+			return true;
+		}
+
+		if (is_LetScrutinee(parent) && parent.expression === node && is_ExpressionWithBodyOrCases(getGrandParentNode())) {
+			return true;
+		}
+		if (is_UnaryExpression(parent) || is_PostfixExpression(parent) || is_MemberExpression(parent)) {
+			return parent.expression === node;
+		}
+		if (is_CallExpression(parent)) {
+			return parent.callee === node;
+		}
+	}
+
+	if (is_LogicalExpression(node) || is_OperationExpression(node) || is_ComparisonExpression(node) || is_ClosureFunctionExpression(node)) {
+		return precedenceNeedsParens(node, parent);
+	}
+
+	if (is_TypeFunctionNode(node)) {
+		const gp = getGrandParentNode();
+		if (node.returnType && is_TypeTraitBound(parent) && is_TypeBoundsStandaloneNode(gp) && last_of(gp.typeBounds) !== parent) {
+			return true;
+		}
+	}
+
+	if (is_TypeBoundsStandaloneNode(node)) {
+		return (
+			(is_UnaryType(parent) && node.typeBounds.length > 1) ||
+			is_TypeBoundsStandaloneNode(parent) ||
+			is_TypeTraitBound(parent) ||
+			(is_TypeFunctionNode(parent) && parent.returnType === node)
+		);
+	}
+
+	if (is_PatternVariableDeclaration(parent)) {
+		return is_UnionPattern(node);
+	}
+
+	return false;
+}
+
+function precedenceNeedsParens(node: LeftRightExpression | ClosureFunctionExpression | ExpressionAsTypeCast, parent: Node) {
+	if (is_UnaryExpression(parent) || is_PostfixExpression(parent)) return true;
+	if (is_ReassignmentNode(parent)) return parent.left === node;
+	if (is_MemberExpression(parent)) return parent.expression === node;
+	if (is_CallExpression(parent)) return parent.callee === node;
+	if (is_ExpressionAsTypeCast(parent)) return !is_ExpressionAsTypeCast(node);
+	if (is_LogicalExpression(parent)) return is_LogicalExpression(node) ? parent.nodeType !== node.nodeType : evalPrecedence(node, parent);
+	if (is_OperationExpression(parent) || is_ComparisonExpression(parent)) return evalPrecedence(node, parent);
+	return false;
+	function evalPrecedence(
+		child: LeftRightExpression | ClosureFunctionExpression | ExpressionAsTypeCast,
+		parent: ComparisonExpression | OperationExpression | LogicalExpression
+	) {
+		if (is_ExpressionAsTypeCast(child) || is_ClosureFunctionExpression(child)) {
+			return true;
+		}
+		function getPrec(node, bool) {
+			// if (is_EqualityOperator(node.tk)) {
+			// 	return 11.3;
+			// }
+			// if (is_LargerLesserOperator(node.tk)) {
+			// 	return 11.6;
+			// }
+			return getPrecedence(node, bool);
+		}
+
+		const childPRCD = getPrec(child, is_insideScrutinee(child));
+		const parentPRCD = getPrec(parent, is_insideScrutinee(parent));
+
+		if (parentPRCD > childPRCD) {
+			return true;
+		}
+
+		if (parentPRCD === childPRCD && parent.right === child) {
+			return true;
+		}
+
+		if (parentPRCD === childPRCD && !shouldFlatten(parent, child)) {
+			return true;
+		}
+
+		if (parentPRCD < childPRCD && child.tk === TK["%"]) {
+			return parentPRCD === PRCD["+-"];
+		}
+
+		if (is_BitwiseOperator(parent.tk) || (is_BitwiseOperator(child.tk) && is_EqualityOperator(parent.tk))) {
+			return true;
+		}
+
+		return false;
+	}
+}
+
+export function shouldFlatten(parent: ExpressionNode | ConditionExpression, node: ExpressionNode | ConditionExpression) {
+	if (getPrecedence(node, is_insideScrutinee(node)) !== getPrecedence(parent, is_insideScrutinee(parent))) return false;
+	if (is_ComparisonExpression(parent) && is_ComparisonExpression(node)) return false;
+	if (is_OperationExpression(parent) && is_OperationExpression(node)) {
+		if (
+			(node.tk === TK["%"] && is_multiplicativeOperator(parent.tk)) ||
+			(parent.tk === TK["%"] && is_multiplicativeOperator(node.tk)) ||
+			(node.tk !== parent.tk && is_multiplicativeOperator(node.tk) && is_multiplicativeOperator(parent.tk)) ||
+			(is_bitshiftOperator(node.tk) && is_bitshiftOperator(parent.tk))
+		)
+			return false;
+	}
+	return true;
+}
+
+export function needsParens(node: Node) {
+	return needsOuterSoftbreakParens(node) || needsInnerParens(node);
+}
+
+export function stmtNeedsSemi(stmt: ExpressionStatement, disregardExprType = false) {
+	return pathCallParentOf(stmt, (parent) => needsSemi(parent as any, stmt, disregardExprType));
+}
+
+const NoNode = { nodeType: 0 } as MissingNode;
+
+export function needsSemi(parent: NodeWithBody, stmt: ExpressionStatement, disregardExprType = false) {
+	const expr = disregardExprType ? NoNode : stmt.expression!;
+	const hadSemi = !disregardExprType && stmt.semi;
+
+	return (
+		!!expr &&
+		(forcePreserveSemi()
+			? true
+			: shouldNeverSemi()
+			? false
+			: shouldPreserveSemi()
+			? hadSemi || shouldAlwaysSemi() || canAutoCompleteSemi()
+			: true)
+	);
+
+	function forcePreserveSemi() {
+		/** Rust Compiler bug (preserve optional semicolon) */
+		// rust-lang/rust#70844 https://github.com/rust-lang/rust/issues/70844
+		// issue#22 https://github.com/jinxdash/prettier-plugin-rust/issues/22
+		return (
+			hadSemi &&
+			stmt === last_of(parent.body!) &&
+			((is_IfBlockExpression(expr) &&
+				hasLetScrutineeCondition(expr) &&
+				!(is_LetScrutinee(expr.condition) && is_Identifier(expr.condition.expression))) ||
+				(is_MatchExpression(expr) && !is_Identifier(expr.expression)))
+		);
+	}
+	function shouldNeverSemi() {
+		return is_ExpressionWithBodyOrCases_or_BlockLikeMacroInvocation(expr);
+	}
+	function shouldPreserveSemi() {
+		return stmt === last_of(parent.body!) && (is_ImplicitReturnAbleNode(parent) || is_BlockLikeMacroInvocation(parent));
+	}
+	function shouldAlwaysSemi() {
+		return is_FlowControlExpression(expr) || is_ReassignmentNode(expr);
+	}
+	function canAutoCompleteSemi() {
+		return withPathAt(parent, function checkParent(child: NodeWithBodyOrCases): boolean {
+			return pathCallParentOf(child, (parent) => {
+				if (is_IfBlockExpression(parent) && parent.else === child) {
+					// if ... { ... } else if { ... } ...
+					// ^ ------------------------------- parent
+					//                     ^ ----------- child
+					return checkParent(parent);
+				}
+				if (is_ExpressionStatement(parent)) {
+					// { .... { ... } ... }
+					// ^ -----------------^ grandparent
+					//        ^ --- ^       ExpressionStatement<child>
+					if (hasOuterAttributes(parent)) return false;
+					return stmtNeedsSemi(parent, true);
+				}
+				if (is_MatchExpressionCase(parent) && parent.expression === child) {
+					return pathCallParentOf(parent, checkParent);
+				}
+				return false;
+			});
+		});
+	}
+}
+
+export function canInlineBlockBody(node: NodeWithBodyOrCases | BlockLikeMacroInvocation): boolean {
+	if (!is_ExpressionWithBody(node)) {
+		return false;
+	}
+	const body = node.body;
+
+	if (body.length === 0) {
+		return canInlineInlineable(node);
+	}
+
+	if (body.length === 1) {
+		const stmt = body[0];
+		if (is_AttributeOrDocComment(stmt)) {
+			return true;
+		}
+		if (is_ExpressionStatement(stmt) && !needsSemi(node, stmt)) {
+			/**
+			 * parent ( ExpressionStatement | StructLiteralProperty | LetVariableDeclaration | ... )
+			 *   ...
+			 *   node {
+			 *     expr
+			 *   }
+			 *   ...
+			 *
+			 *
+			 * Q: Can you inline "node { expr }" ?
+			 */
+			const expr = stmt.expression!;
+
+			if (
+				is_FlowControlExpression(expr) || //
+				is_ClosureFunctionExpression(expr) ||
+				is_ExpressionWithBodyOrCases_or_BlockLikeMacroInvocation(expr)
+			) {
+				return false;
+			}
+
+			return canInlineInlineable(node);
+		}
+	}
+	return false;
+}
+
+// function q(node: ExpressionWithBody) {
+// 	pathCallTopMostIfBlockExpression(node, (node) => {});
+// }
+
+function canInlineInlineable(node: ExpressionWithBody) {
+	if (is_ForInBlockExpression(node) || is_LoopBlockExpression(node)) {
+		return false;
+	}
+	if (is_WhileBlockExpression(node)) {
+		return true;
+	}
+
+	const parent = getParentNode(node)!;
+
+	if (
+		is_ExpressionStatement(parent) &&
+		(!is_ImplicitReturnAbleNode(node) || pathCallAtParent(parent, (parent) => stmtNeedsSemi(parent, true)))
+	) {
+		return false;
+	}
+
+	if (is_ElseBlock(node, parent)) {
+		return pathCallAtParent(parent, canInlineBlockBody);
+	}
+	// if (is_CaseBlock(node, parent)) {
+	// 	return false;
+	// }
+	if (is_IfBlockExpression(node)) {
+		if (
+			!node.else ||
+			// hasLetScrutineeCondition(node) ||
+			is_ExpressionWithBodyOrCases_or_BlockLikeMacroInvocation(node.condition) ||
+			willBreak(getPrintFn(node)("condition"))
+		) {
+			return false;
+		}
+
+		const grandparent = getGrandParentNode();
+		if (is_ExpressionStatement(parent) && hasBody(grandparent) && grandparent.body.length > 1) {
+			return false;
+		}
+	}
+	return true;
+	return (
+		is_CallExpression_or_CallLikeMacroInvocation(parent) ||
+		hasItems(parent) ||
+		hasProperties(parent) ||
+		is_ClosureFunctionExpression(parent) ||
+		is_MemberExpression(parent) ||
+		is_AwaitExpression(parent) ||
+		is_LeftRightExpression(parent)
+	);
+}
+
+type NodeWithBracketContent =
+	| NodeWithBodyOrCases
+	| BlockLikeMacroInvocation
+	| EnumDeclaration
+	| StructDeclaration
+	| StructLiteral
+	| StructPattern
+	| EnumMemberStructDeclaration
+	| UnionDeclaration
+	| MacroRulesDeclaration
+	| MacroDeclaration;
+
+export function emptyContent(node: NodeWithBracketContent): Doc {
+	switch (node.nodeType) {
+		case NodeType.Program:
+		case NodeType.MacroRulesDeclaration:
+		case NodeType.MacroDeclaration:
+		case NodeType.ExternBlockDeclaration:
+		case NodeType.ModuleDeclaration:
+		case NodeType.TraitDeclaration:
+		case NodeType.StructDeclaration:
+		case NodeType.MacroInvocation:
+		case NodeType.FunctionDeclaration:
+		case NodeType.ImplDeclaration:
+		case NodeType.UnionDeclaration:
+		case NodeType.EnumDeclaration:
+		case NodeType.EnumMemberStructDeclaration:
+		case NodeType.StructLiteral:
+		case NodeType.StructPattern:
+			// case NodeType.MatchExpression:
+			return "";
+		case NodeType.BlockExpression:
+		case NodeType.WhileBlockExpression:
+		case NodeType.ForInBlockExpression:
+		case NodeType.TryBlockExpression:
+		case NodeType.IfBlockExpression:
+			return canInlineInlineable(node)
+				? is_IfBlockExpression(node) || is_ElseBlock(node, getParentNode()!)
+					? softline
+					: ""
+				: hardline;
+		case NodeType.LoopBlockExpression:
+		case NodeType.MatchExpression:
+			return hardline;
+		default:
+			if (is_NodeWithBodyNoBody(node)) {
+				return "";
+			}
+			__DEV__: exit.never(node);
+			return "";
+	}
+}
+
+export function is_insideScrutinee(target: Node) {
+	return withPathAt(target, (n) => stackIncludes("condition") && r(n));
+	function r(CHILD: Node) {
+		switch (CHILD.nodeType) {
+			case NodeType.OrExpression:
+			case NodeType.AndExpression:
+				return pathCallParentOf(CHILD, (PARENT) =>
+					hasCondition(PARENT) && PARENT.condition === CHILD //
+						? hasLetScrutineeCondition(PARENT)
+						: r(PARENT)
+				);
+			case NodeType.LetScrutinee:
+				return true;
+			default:
+				return false;
+		}
+	}
+}
+
+function withPathAt<T extends Node, R>(target: T, callback: (target: T) => R): R {
+	if (target === getNode()) return callback(target);
+	if (target === getParentNode()) return pathCallAtParent(target, () => callback(target));
+	if (stackIncludes(target)) return pathCallAtParent(getParentNode()!, () => withPathAt(target, callback));
+	return getContext().path.call(() => {
+		__DEV__: assertPathAtNode("withPathAt", target);
+		return callback(target); // @ts-ignore
+	}, ...getAstPath(getNode(), target));
+}
+export function shouldPrintOuterAttributesAbove(node: Node) {
+	return (
+		is_StatementNode(node) ||
+		is_MatchExpressionCase(node) ||
+		(hasAttributes(node) &&
+			node.attributes.some(
+				canInlineOuterAttribute(node)
+					? (attr) => is_DocCommentAttribute(attr) || hasBreaklineAfter(attr) //
+					: is_DocCommentAttribute
+			))
+	);
+	function canInlineOuterAttribute(node: Node) {
+		return (
+			is_EnumMemberDeclaration(node) ||
+			is_StructPropertyDeclaration(node) ||
+			is_StructLiteralProperty(node) ||
+			is_StructPatternProperty(node)
+		);
+	}
+}

frontend/src/utils/prettier/plugins/rust/index.ts

@@ -0,0 +1,8 @@
+import { plugin } from "./format/plugin";
+
+export default plugin;
+export const languages = plugin.languages;
+export const parsers = plugin.parsers;
+export const printers = plugin.printers;
+export const options = plugin.options;
+export const defaultOptions = plugin.defaultOptions;

frontend/src/utils/prettier/plugins/rust/transform/custom/attribute.ts

@@ -0,0 +1,116 @@
+import {
+	AttrSegment,
+	CallExpression,
+	DelimKind,
+	ExpressionPath,
+	Identifier,
+	Literal,
+	LocArray,
+	MacroInvocation,
+	NodeType,
+	PunctuationToken,
+	ReassignmentExpression,
+	TK,
+	rs,
+} from "jinx-rust";
+import { isTK, start } from "jinx-rust/utils";
+import { assert, exit } from "../../utils/common";
+import { isIdent } from "./utils";
+
+type SimpleAttrItem =
+	| Identifier //
+	| Literal
+	| ExpressionPath
+	| CallExpression
+	| ReassignmentExpression
+	| MacroInvocation;
+
+export function transform_simpleAttrSyntax(segments: MacroInvocation["segments"]) {
+	assert(segments.length !== 0, segments.loc.url());
+	return transform_segments(segments, false);
+
+	function transform_segments<N extends boolean>(
+		seq: LocArray<AttrSegment>,
+		nestedCall: N
+	): N extends true ? LocArray<SimpleAttrItem, "()"> : SimpleAttrItem {
+		let i = 0;
+
+		if (nestedCall) {
+			const args = rs.createLocArray<SimpleAttrItem, any>(DelimKind["()"], seq.loc.clone());
+			while (i !== seq.length) {
+				args.push(read(true));
+				if (i === seq.length) break;
+				assert(isTK(seq[i++], TK[","]));
+			}
+			return args as any;
+		} else {
+			const res = read(true);
+			assert(i === seq.length, res.loc.url());
+			return res as any;
+		}
+
+		function read(allowEq: boolean): SimpleAttrItem {
+			let lhs: Identifier | ExpressionPath;
+
+			switch (seq[i].nodeType) {
+				case NodeType.Literal:
+					return seq[i++] as Literal;
+				case NodeType.Identifier:
+					lhs = seq[i++] as Identifier;
+					break;
+				case NodeType.PunctuationToken:
+					assert((seq[i] as PunctuationToken).tk === TK["::"], seq[i].loc.url());
+					lhs = eatPathSegment(undefined);
+					break;
+				default:
+					exit.never();
+			}
+
+			while (true) {
+				if (i === seq.length) return lhs;
+				const seg = seq[i];
+				switch (seg.nodeType) {
+					case NodeType.PunctuationToken:
+						switch (seg.tk) {
+							case TK[","]:
+								assert(nestedCall);
+								return lhs;
+							case TK["="]: {
+								assert(allowEq);
+								const right = (i++, read(false));
+								return rs.mockNode(NodeType.ReassignmentExpression, right.loc.cloneFrom(start(lhs)), {
+									tk: TK["="],
+									kind: DelimKind["="],
+									left: lhs,
+									right,
+								});
+							}
+							case TK["::"]:
+								lhs = eatPathSegment(lhs);
+								continue;
+							default:
+								exit.never();
+						}
+					case NodeType.DelimGroup:
+						assert(seg.segments.dk === DelimKind["()"]);
+						return rs.mockNode(NodeType.CallExpression, seq[i++].loc.cloneFrom(start(lhs)), {
+							callee: lhs,
+							typeArguments: undefined,
+							method: undefined,
+							arguments: transform_segments(seg.segments, true),
+						});
+					default:
+						exit.never();
+				}
+			}
+		}
+
+		function eatPathSegment(left: undefined | Identifier | ExpressionPath) {
+			const segment = seq[i + 1];
+			assert(isIdent(segment));
+			const res = rs.mockNode(NodeType.ExpressionPath, segment.loc.cloneFrom(start(left ?? seq[i])), { namespace: left, segment });
+			i += 2;
+			return res;
+		}
+	}
+}

frontend/src/utils/prettier/plugins/rust/transform/custom/cfg_if.ts

@@ -0,0 +1,92 @@
+import {
+	DelimGroup,
+	DelimKind,
+	IfBlockExpression,
+	LocArray,
+	MacroInvocation,
+	NodeType,
+	NodeWithBody,
+	rs,
+	Segment,
+	Snippet,
+	StatementNode,
+	TK,
+} from "jinx-rust";
+import { insertNodes, start, transferAttributes } from "jinx-rust/utils";
+import { assert, iLast } from "../../utils/common";
+import { isGroup, isIdent, isToken } from "./utils";
+
+export function transform_macro_cfg_if(segments: MacroInvocation["segments"]) {
+	const danglingAttributes: Snippet["danglingAttributes"] = [];
+	const comments: Snippet["comments"] = [];
+
+	const block = (function create_if_block(i: number): IfBlockExpression | undefined {
+		if (i >= segments.length) return undefined;
+
+		const _if = segments[i];
+		const pound = segments[i + 1];
+		const grp = segments[i + 2];
+		const block = segments[i + 3];
+		const _else = segments[i + 4];
+
+		assert(
+			isIdent(_if, "if") &&
+				isToken(pound, TK["#"]) &&
+				isGroup(grp, DelimKind["[]"]) &&
+				isGroup(block, DelimKind["{}"]) &&
+				(!_else || isIdent(_else, "else"))
+		);
+
+		return create_block(block, (body) =>
+			rs.mockNode(NodeType.IfBlockExpression, block.loc.cloneFrom(start(_if)), {
+				label: undefined,
+				condition: rs.mockNode(NodeType.Attribute, grp.loc.cloneFrom(start(pound)), {
+					segments: grp.segments,
+					value: grp.segments.loc.sliceText(),
+					line: false,
+					inner: false,
+				}) as any,
+				body: body,
+				else: (_else && iLast(i + 5, segments)
+					? function create_else_block(i: number) {
+							const block = segments[i];
+							assert(isGroup(block, DelimKind["{}"]));
+							return create_block(block, (body) =>
+								rs.mockNode(NodeType.BlockExpression, body.loc.clone(), {
+									label: undefined,
+									body,
+								})
+							);
+					  }
+					: create_if_block)(i + 5),
+			})
+		);
+	})(0);
+
+	const ast = rs.createLocArray(
+		segments.dk,
+		segments.loc,
+		block && [
+			rs.mockNode(NodeType.ExpressionStatement, block.loc.clone(), {
+				expression: block,
+				semi: false,
+			}),
+		]
+	);
+
+	return rs.mockNode(NodeType.Snippet, segments.loc.clone(), { ast, danglingAttributes, comments });
+
+	function create_block<R extends NodeWithBody>(
+		group: DelimGroup<Segment> & { segments: { dk: 3 } },
+		fn: (statements: LocArray<StatementNode, "{}">) => R
+	): R {
+		const snippet = rs.toBlockBody(group.segments);
+
+		insertNodes(danglingAttributes, snippet.danglingAttributes);
+		insertNodes(comments, snippet.comments);
+
+		const block = fn(snippet.ast);
+		transferAttributes(snippet, block);
+		return block;
+	}
+}

frontend/src/utils/prettier/plugins/rust/transform/custom/utils.ts

@@ -0,0 +1,16 @@
+import { DelimGroup, DelimKind, Identifier, LocArray, PunctuationToken, Segment, TK } from "jinx-rust";
+import { isTK, is_DelimGroup, is_Identifier, is_PunctuationToken } from "jinx-rust/utils";
+
+export function isIdent(node: Segment | undefined, name?: string): node is Identifier {
+	return !!node && is_Identifier(node) && (null == name || node.name === name);
+}
+export function isToken(node: Segment | undefined, tk?: TK): node is PunctuationToken {
+	return !!node && (null == tk ? is_PunctuationToken(node) : isTK(node, tk));
+}
+export function isGroup<D extends DelimKind>(node: Segment | undefined, dk?: D): node is DelimGroup & { segments: LocArray<any, D> } {
+	return !!node && is_DelimGroup(node) && (null == dk || node.segments.dk === dk);
+}
+
+export function isCallLike(tk_1: Segment | undefined, tk_2: Segment | undefined): boolean {
+	return !!tk_1 && !!tk_2 && is_Identifier(tk_1) && is_DelimGroup(tk_2) && tk_2.segments.dk === DelimKind["()"];
+}

frontend/src/utils/prettier/plugins/rust/transform/index.ts

@@ -0,0 +1,568 @@
+import {
+	Attribute,
+	AttributeOrDocComment,
+	CallExpression,
+	DelimKind,
+	ExpressionNode,
+	LocArray,
+	MacroInvocation,
+	MemberExpression,
+	Node,
+	NodeType,
+	NodeWithBodyNoBody,
+	NodeWithTypeBounds,
+	NTMap,
+	ProgramLike,
+	rs,
+	Snippet,
+	StatementNode,
+	StructLiteral,
+	StructPattern,
+	TK,
+	TypeBound,
+	TypeBoundsStandaloneNode,
+	TypeDynBounds,
+	TypeTraitBound,
+} from "jinx-rust";
+import {
+	countActualNodeChildren,
+	deleteAttributes,
+	each_childNode,
+	end,
+	getActualNodeChildren,
+	getBodyOrCases,
+	getMacroName,
+	getNodeChildren,
+	hasAttributes,
+	hasMethod,
+	hasTypeBounds,
+	includesTK,
+	insertNode,
+	insertNodes,
+	is_AttributeOrDocComment,
+	is_BareTypeTraitBound,
+	is_BlockExpression,
+	is_CallExpression,
+	is_ClosureFunctionExpression,
+	is_DocCommentAttribute,
+	is_ExpressionStatement,
+	is_ExpressionWithBodyOrCases,
+	is_FlowControlExpression,
+	is_IfBlockExpression,
+	is_MacroInvocation,
+	is_Node,
+	is_NodeWithBodyNoBody,
+	is_NodeWithBodyOrCases,
+	is_Program,
+	is_PunctuationToken,
+	is_ReassignmentNode,
+	is_Snippet,
+	is_TypeBoundsStandaloneNode,
+	is_TypeDynBounds,
+	is_TypeImplBounds,
+	is_TypeTraitBound,
+	ownStart,
+	reassignNodeProperty,
+	start,
+	transferAttributes,
+	unsafe_set_nodeType,
+} from "jinx-rust/utils";
+import { isPrettierIgnoreAttribute, setPrettierIgnoreTarget } from "../format/comments";
+import { is_StructSpread } from "../format/core";
+import { CustomOptions } from "../format/external";
+import { getOptions } from "../format/plugin";
+import {
+	Array_replace,
+	Array_splice,
+	assert,
+	binarySearchIn,
+	each,
+	exit,
+	iLast,
+	last_of,
+	Map_get,
+	spliceAll,
+	try_eval,
+} from "../utils/common";
+import { transform_simpleAttrSyntax } from "./custom/attribute";
+import { transform_macro_cfg_if } from "./custom/cfg_if";
+
+export interface ExpressionLikeAttribute extends Attribute {
+	segments: LocArray<any, "[]">;
+}
+
+export interface CallLikeMacroInvocation extends MacroInvocation {
+	segments: LocArray<any, any>;
+	callee: MacroInvocation["callee"];
+	method: undefined;
+	typeArguments: undefined;
+	arguments: LocArray<ExpressionNode, "()" | "[]" | "{}">;
+}
+
+export interface BlockLikeMacroInvocation extends MacroInvocation {
+	segments: LocArray<any, any>;
+	body: LocArray<StatementNode, "()" | "[]" | "{}">;
+	attributes?: AttributeOrDocComment[];
+}
+
+export function is_CallLikeMacroInvocation(node: Node): node is CallLikeMacroInvocation {
+	return is_MacroInvocation(node) && "arguments" in node;
+}
+
+export function is_BlockLikeMacroInvocation(node: Node): node is BlockLikeMacroInvocation {
+	return is_MacroInvocation(node) && "body" in node;
+}
+
+export function is_CallExpression_or_CallLikeMacroInvocation(node: any): node is CallExpression | CallLikeMacroInvocation {
+	return is_CallExpression(node) || is_CallLikeMacroInvocation(node);
+}
+
+const IGNORED_MACROS = new Set([
+	// std
+	// crates
+	"quote",
+]);
+
+const HARDCODED_MACRO_DELIMS = new Map<string, MacroInvocation["segments"]["dk"]>();
+each(
+	{
+		[DelimKind["{}"]]: [
+			// std
+			"thread_local",
+			// crates
+			"cfg_if",
+		],
+		[DelimKind["()"]]: [
+			// std
+			"assert_eq",
+			"assert_ne",
+			"assert",
+			"cfg",
+			"concat_bytes",
+			"concat_idents",
+			"concat",
+			"debug_assert_eq",
+			"debug_assert_ne",
+			"debug_assert",
+			"eprint",
+			"eprintln",
+			"format_args_nl",
+			"format_args",
+			"format",
+			"matches",
+			"panic",
+			"print",
+			"println",
+			"try",
+			"unimplemented",
+			"unreachable",
+			"write",
+			"writeln",
+			// crates
+		],
+		[DelimKind["[]"]]: [
+			// std
+			"vec",
+			// crates
+		],
+	},
+	(names, tk) =>
+		each(names, (name) => {
+			HARDCODED_MACRO_DELIMS.set(name, +tk as MacroInvocation["segments"]["dk"]);
+		})
+);
+
+let _COMMENTS: CustomOptions["comments"] = undefined!;
+let _DANGLING_ATTRIBUTES: CustomOptions["danglingAttributes"] = undefined!;
+
+export function transform_ast(options: CustomOptions) {
+	try {
+		_COMMENTS = options.comments;
+		_DANGLING_ATTRIBUTES = options.danglingAttributes;
+		transformNode(options.rsParsedFile);
+	} finally {
+		_depth = 0;
+		_COMMENTS = undefined!;
+		_DANGLING_ATTRIBUTES = undefined!;
+	}
+}
+
+let _depth = 0;
+const isReadingSnippet = () => 0 !== _depth;
+
+function maybe_transform_node<T extends Node, S extends Snippet>(
+	node: T,
+	read_snippet: () => S,
+	fn: (node: T, snippet: S) => void
+): T | undefined {
+	const snippet = try_eval(read_snippet);
+	if (snippet) {
+		++_depth;
+		transformNode(snippet);
+		--_depth;
+		fn(node, snippet);
+		transformed.add(node);
+		return node;
+	}
+}
+const transformed = new WeakSet<Node>();
+export function isTransformed(node: Node) {
+	return transformed.has(node);
+}
+
+const transform: { [K in NodeType]?: (node: NTMap[K]) => void } = {
+	[NodeType.Attribute](node) {
+		try_eval(() => {
+			node.segments = rs.createLocArray(node.segments.dk, node.segments.loc.clone(), [
+				transform_simpleAttrSyntax(node.segments),
+			]) as any;
+			transformed.add(node);
+		});
+	},
+	[NodeType.MacroInlineRuleDeclaration](node) {
+		node.match.dk = DelimKind["()"];
+		node.transform.dk = DelimKind["{}"];
+	},
+	[NodeType.MacroInvocation](node) {
+		const name = getMacroName(node);
+
+		if (
+			IGNORED_MACROS.has(name) ||
+			node.segments.length === 0 ||
+			(node.segments.length === 1 && is_PunctuationToken(node.segments[0]))
+		) {
+			return;
+		}
+
+		const tk = transformMacroDelim(name, node);
+
+		if (name === "matches") {
+			//
+		}
+
+		if (name === "if_chain") {
+			//
+		}
+
+		if (name === "cfg_if") {
+			transformBlockLike(() => transform_macro_cfg_if(node.segments) as any);
+		} else if (tk === DelimKind["{}"]) {
+			transformBlockLike(); /* || (includesTK(node, TK[","]) && transformCallLike()); */
+		} else {
+			transformCallLike(); /* || (includesTK(node, TK[";"]) && transformBlockLike()); */
+		}
+
+		function transformBlockLike(transform = () => rs.toBlockBody(node.segments)) {
+			return maybe_transform_node(node as BlockLikeMacroInvocation, transform, (node, snippet) => {
+				const _body = snippet.ast;
+				_body.dk = tk;
+
+				node.body = _body;
+				node.segments = _body;
+				transferAttributes(snippet, node);
+			});
+		}
+
+		function transformCallLike() {
+			return maybe_transform_node(
+				node as CallLikeMacroInvocation,
+				() => rs.toCallExpressionArguments(node.segments),
+				(node, snippet) => {
+					const _arguments = snippet.ast;
+					_arguments.dk = tk;
+
+					node.method = undefined;
+					node.typeArguments = undefined;
+					node.arguments = _arguments;
+					node.segments = _arguments;
+				}
+			);
+		}
+	},
+	[NodeType.CallExpression](node) {
+		if (hasMethod(node)) {
+			node.callee = rs.mockNode(NodeType.MemberExpression, node.method.loc.cloneFrom(start(node.callee)), {
+				expression: node.callee,
+				property: node.method,
+				computed: false,
+			});
+			node.method = undefined!;
+			getOptions().actuallyMethodNodes.add(node.callee as MemberExpression);
+		}
+	},
+
+	[NodeType.AutoTraitDeclaration](node) {
+		mockBodyNoBody(node);
+	},
+	[NodeType.NegativeImplDeclaration](node) {
+		mockBodyNoBody(node);
+	},
+
+	[NodeType.StructLiteral](node) {
+		moveSpreadsToEnd(node);
+	},
+	[NodeType.StructPattern](node) {
+		moveSpreadsToEnd(node);
+	},
+};
+
+function moveSpreadsToEnd(node: StructLiteral | StructPattern) {
+	const props = node.properties;
+	if (props.some((p, i, a) => is_StructSpread(p) && !iLast(i, a))) {
+		const spreads: any[] = [];
+		for (let i = 0; i < props.length; i++) {
+			const prop = props[i];
+			if (is_StructSpread(prop)) {
+				Array_splice(props, prop, i--);
+				spreads.push(prop);
+			}
+		}
+		props.push(...spreads);
+	}
+}
+
+function mockBodyNoBody(node: NodeWithBodyNoBody) {
+	// @ts-expect-error
+	node.body = rs.createLocArray(last_of(rs.toTokens(node).ast).loc.clone(), DelimKind["{}"]);
+}
+
+function transformMacroDelim(name: string, node: MacroInvocation): 1 | 2 | 3 {
+	if (HARDCODED_MACRO_DELIMS.has(name)) {
+		return HARDCODED_MACRO_DELIMS.get(name)!;
+	}
+	if (node.segments.dk === DelimKind["{}"] && includesTK(node, TK[","])) {
+		return DelimKind["()"];
+	}
+	if (node.segments.dk === DelimKind["()"] && includesTK(node, TK[";"])) {
+		return DelimKind["{}"];
+	}
+	return node.segments.dk;
+}
+
+// export function createTransformed<S extends Node>(create: () => S): S {
+// 	return transformNode(create());
+// }
+
+const seen = new WeakSet<Node>();
+function transformNode<T extends Node>(node: T, parent?: Node, key?: string, index?: any): T {
+	if (!seen.has(node)) {
+		seen.add(node);
+		if (is_Snippet(node) || is_Program(node)) {
+			registerPogramLike(node);
+		}
+
+		each_childNode(node, transformNode);
+
+		insert_blocks(node, parent, key, index);
+
+		transform[node.nodeType]?.(node as any);
+
+		flatten_typeBounds(node);
+
+		transform_nodeAttributes(node);
+	}
+	return node;
+}
+
+function insert_blocks(node: Node, parent?: Node, key?: string, index?: any) {
+	if (parent && key) {
+		if (
+			!is_ExpressionStatement(parent) &&
+			(false ||
+				// "1 + break" -> "1 + { break; }"
+				is_FlowControlExpression(node) ||
+				// "1 + a = b" -> "1 + { a = b; }"
+				(!isReadingSnippet() && is_ReassignmentNode(node) && !(is_ReassignmentNode(parent) && parent.left === node)))
+		) {
+			reassignNodeProperty(blockify(node), parent, key, index);
+		} else if (
+			is_ClosureFunctionExpression(node) &&
+			(false ||
+				// "|| -> T x" -> "|| -> T { x }"
+				(!!node.returnType && !is_BlockExpression(node.expression)) ||
+				// "|| match x {}" -> "|| { match x {} }"
+				(is_ExpressionWithBodyOrCases(node.expression) &&
+					!is_BlockExpression(node.expression) &&
+					!is_IfBlockExpression(node.expression)))
+		) {
+			node.expression = blockify(node.expression);
+		}
+	}
+	function blockify(node: ExpressionNode) {
+		const block = rs.mockNode(NodeType.BlockExpression, node.loc.clone(), {
+			label: undefined,
+			body: rs.createLocArray(DelimKind["{}"], node.loc.clone(), [
+				rs.mockNode(NodeType.ExpressionStatement, node.loc.clone(), { semi: false, expression: node }),
+			]),
+		});
+		transferAttributes(node, block);
+		return block;
+	}
+}
+
+function flatten_typeBounds(topNode: Node) {
+	if (hasTypeBounds(topNode)) {
+		const nestedBounds: TypeTraitBound[] = topNode.typeBounds.filter(isBoundWithNestedBounds);
+		const [first, ...subsequent] = nestedBounds;
+
+		const flatten = (bound: TypeTraitBound) =>
+			Array_replace(topNode.typeBounds, bound, ...(bound.typeExpression as unknown as TypeDynBounds).typeBounds);
+
+		if (nestedBounds.every(isBareBoundWithNestedBoundsNoPrefix)) {
+			// A + (B + C)
+			// -> A + B + C
+			each(nestedBounds, flatten);
+		} else if (
+			!hasDefinedPrefix(topNode) &&
+			first === topNode.typeBounds[0] &&
+			!isBareBoundWithNestedBoundsNoPrefix(first) &&
+			subsequent.every(isBareBoundWithNestedBoundsNoPrefix)
+		) {
+			if (is_TypeDynBounds(topNode)) {
+				if (is_TypeImplBounds(first.typeExpression)) {
+					// (impl A) + B
+					// -> impl A + B
+					unsafe_set_nodeType(topNode, NodeType.TypeImplBounds);
+				} else {
+					// (dyn A) + B
+					// -> dyn A + B
+					topNode.dyn = true;
+				}
+				each(nestedBounds, flatten);
+			} else {
+				each(subsequent, flatten);
+				(first.typeExpression as unknown as TypeDynBounds).typeBounds.push(...topNode.typeBounds.slice(1));
+				topNode.typeBounds.length = 1;
+			}
+		}
+	}
+
+	function isBoundWithNestedBounds(bound: TypeBound): bound is TypeTraitBound & { typeExpression: TypeBoundsStandaloneNode } {
+		return is_TypeTraitBound(bound) && is_TypeBoundsStandaloneNode(bound.typeExpression);
+	}
+	function isBareBoundWithNestedBounds(bound: TypeBound): bound is TypeTraitBound & { typeExpression: TypeBoundsStandaloneNode } {
+		return isBoundWithNestedBounds(bound) && is_BareTypeTraitBound(bound);
+	}
+	function isBareBoundWithNestedBoundsNoPrefix(bound: TypeBound): bound is TypeTraitBound & { typeExpression: TypeDynBounds } {
+		return isBareBoundWithNestedBounds(bound) && !hasDefinedPrefix(bound.typeExpression);
+	}
+	function hasDefinedPrefix(node: NodeWithTypeBounds) {
+		return (is_TypeDynBounds(node) && node.dyn) || is_TypeImplBounds(node);
+	}
+}
+
+function transform_nodeAttributes(node: Node) {
+	/**
+	 * # Inside Token trees:
+	 *
+	 *  1. DocCommentAttribute 	--is parsed as--> 	Comment
+	 *  2. Attribute 			--is parsed as--> 	Token<'#'>, DelimGroup<'[]'>
+	 *
+	 * # Transforming tokens into a Snippet:
+	 *
+	 *  1. DocCommentAttribute <--replace from-- Comment
+	 *    a) Remove node with same loc from comments
+	 *    b) Merge Snippet.danglingAttributes with Program.danglingAttributes
+	 *
+	 *  2. Attribute (no action needed)
+	 *
+	 */
+	if (hasAttributes(node)) {
+		const attrs = node.attributes;
+		for (let i = 0; i < attrs.length; i++) {
+			const attr = attrs[i];
+			if (isReadingSnippet() && is_DocCommentAttribute(attr)) {
+				const index = binarySearchIn(_COMMENTS, start(attr), start);
+				__DEV__: assert(index !== -1), assert(end(_COMMENTS[index]) === end(attr));
+				_COMMENTS.splice(index, 1);
+			}
+			if (attr.inner) {
+				if (isPrettierIgnoreAttribute(attr)) {
+					setPrettierIgnoreTarget(is_Program(node) ? node.loc.src : node, attr);
+				}
+				// @ts-expect-error Inserting Attribute into StatementNode[]
+				insertNode(is_Snippet(node) ? node.ast : getBodyOrCases(node)!, attr);
+				Array_splice(attrs, attr, i--);
+			}
+		}
+		if (attrs.length === 0) {
+			deleteAttributes(node);
+		}
+	}
+}
+
+function registerPogramLike(program: Extract<Node, ProgramLike>) {
+	const comments = spliceAll(program.comments);
+	const danglingAttributes = spliceAll(program.danglingAttributes);
+	for (let i = 0; i < danglingAttributes.length; i++) {
+		const attr = danglingAttributes[i];
+		// if (isReadingSnippet() && is_DocCommentAttribute(attr)) {
+		// }
+		if (is_DocCommentAttribute(attr)) {
+			if (isReadingSnippet()) {
+				const index = binarySearchIn(_COMMENTS, start(attr), start);
+				__DEV__: assert(index !== -1), assert(end(_COMMENTS[index]) === end(attr));
+				_COMMENTS.splice(index, 1);
+			}
+		} else {
+			transformNode(danglingAttributes[i], program, "danglingAttributes", i);
+		}
+	}
+	if (!isReadingSnippet()) insertNodes(_COMMENTS, comments);
+	insertNodes(_DANGLING_ATTRIBUTES, danglingAttributes);
+}
+
+const CommentChildNodes = new WeakMap<Node, Node[]>();
+
+export function getCommentChildNodes(n: any): Node[] {
+	const children = Map_get(CommentChildNodes, n, getTransformedNodeChildren);
+	/**
+	 * parent {
+	 *  #[attr]
+	 * 	#![attr] <-------- list misplaced inner attrs as part of "#[attr] child {}"
+	 * 	child {}
+	 * }
+	 */
+	if (is_NodeWithBodyOrCases(n) || is_BlockLikeMacroInvocation(n)) {
+		for (let i = 0; i < children.length; i++) {
+			const attr = children[i];
+			if (is_AttributeOrDocComment(attr)) {
+				const target = children.find((n) => start(n) <= start(attr) && ownStart(n) >= end(attr));
+				if (target) {
+					children.splice(i--, 1);
+					insertNode(Map_get(CommentChildNodes, target, getTransformedNodeChildren), attr);
+				}
+			}
+		}
+	}
+	return children;
+
+	function getTransformedNodeChildren(node: Node) {
+		if (is_Program(node)) node.comments ??= []; // prettier core deletes this property
+		const children = getNodeChildren(node);
+
+		if (is_NodeWithBodyNoBody(node)) {
+			insertNodes(children, (node as any).body);
+		}
+
+		__DEV__: {
+			const actual_count = countActualNodeChildren(node);
+			if (
+				children.length !== actual_count &&
+				!(is_MacroInvocation(node) && actual_count - node.segments.length === children.length)
+			) {
+				const actual = getActualNodeChildren(node);
+				const missing = actual.filter((n) => !children.includes(n));
+				const unknown = children.filter((n) => !actual.includes(n));
+				const duplicates_in_object = actual.filter((n, i, a) => i !== 0 && n === a[i - 1]);
+				const duplicates_in_childNodes = children.filter((n, i, a) => i !== 0 && n === a[i - 1]);
+				const ctx = { missing, unknown, duplicates_in_object, duplicates_in_childNodes };
+				for (let key in ctx) if (ctx[key].length === 0) delete ctx[key];
+				exit(`${node.type} was transformed but did not patch its childNodes list`, ctx, node.loc.url(), node);
+			}
+			for (const child of children)
+				if (!is_Node(child)) exit(`${node.type}'s childNodes includes unexpected entries`, { node, child });
+		}
+		return children;
+	}
+}

frontend/src/utils/prettier/plugins/rust/utils/common.ts

@@ -0,0 +1,246 @@
+import { createCustomError } from "./debug";
+
+declare global {
+	interface ImportMeta {
+		url: string;
+	}
+}
+
+export function Narrow<T extends R, R = unknown>(value: R): asserts value is T {}
+export function AssertTypesEq<A extends B, B>(...args: [B] extends [A] ? [] : [RIGHT_TYPES_NOT_ASSIGNABLE_TO_LEFT: Exclude<B, A>]) {}
+
+// prettier-ignore
+type indexof<A> = A extends readonly any[] ? A extends 0 ? any : keyof A & number : A extends Set<unknown> ? never : A extends Map<infer U, unknown> ? U 
+	: A extends Iterable<unknown> ? never : A extends object ? keyof A & (number | string) : never;
+// prettier-ignore
+type valueof<A> = A extends ReadonlyArray<infer U> ? A extends 0 ? any : U : A extends Set<infer U> ? U : A extends Map<unknown, infer U> ? U 
+	: A extends Iterable<infer U> ? U : A extends object ? A[keyof A & (number | string)] : never;
+// prettier-ignore
+type vObject<V extends unknown = unknown, K extends unknown = unknown> = | object | readonly V[] | { [key: string]: V } | anySet<V> | anyMap<K, V>;
+export type itfn<A, R> = (value: valueof<A>, key: indexof<A>) => R;
+type anySet<V extends unknown = unknown> = Set<V>;
+type anyMap<K extends unknown = unknown, V extends unknown = unknown> = Map<K, V>;
+type anyfunction<A extends any[] = unknown[], R = unknown> = (...args: A) => R;
+type objlike = object | anyfunction;
+type anymap<K extends unknown = unknown, V extends unknown = unknown> = K extends objlike ? Map<K, V> | WeakMap<K, V> : Map<K, V>;
+
+export function exit(message: string, ...ctx: any[]): never {
+	if (ctx.length > 0) console.log("Error context:", { ...ctx });
+	throw createCustomError({ message });
+}
+exit.never = function never(...ctx: any[]): never {
+	exit("Reached unreachable code", ...ctx);
+};
+export function assert(predicate: boolean, err?: string, ...ctx: any[]): asserts predicate {
+	__DEV__: if (typeof predicate !== "boolean") exit("Expected boolean", predicate);
+	if (false === predicate) exit(err ?? "Assertion failed", ...ctx);
+}
+export function Identity<T>(v: T): T {
+	return v;
+}
+
+export function last_of<T extends ArrayLike<any>>(arr: T): T extends readonly [...infer A, infer U] ? U : T[number] {
+	__DEV__: isArrayLike(arr) || exit("Expected Array"), arr.length > 0 || exit("Attempted to retrieve last item of an empty array", arr);
+	return arr[arr.length - 1];
+}
+export function maybe_last_of<T extends readonly any[] | undefined>(
+	arr: T
+): T extends any[] ? (T extends readonly [...infer A, infer U] ? U : T[number]) : undefined {
+	return (undefined === arr || 0 === arr.length ? undefined : last_of(arr as any[])) as any;
+}
+
+export function normPath(filepath: string) {
+	return filepath.replace(/^file:\/\/\//, "").replace(/\\\\?/g, "/");
+}
+
+export function print_string(str: string) {
+	return /[\u0000-\u0020]/.test(str)
+		? str
+				.replace(/ /g, "•")
+				.replace(/\n/g, "↲")
+				.replace(/\t/g, "╚")
+				.replace(/[\u0000-\u0020]/g, "□")
+		: str;
+}
+
+function isArrayLike(value: any): value is ArrayLike<unknown> {
+	return is_object(value) && oisArrayLike(value);
+}
+
+function oisArrayLike(value: {}): value is ArrayLike<unknown> {
+	return "length" in value && (0 === (value as any).length || "0" in value);
+}
+
+export function binarySearchIn<T extends {}>(array: ArrayLike<T>, target: number, toValue: (item: T) => number) {
+	if (isEmpty(array)) return -1;
+	let i = 0;
+	let low = 0;
+	let high = array.length - 1;
+	let value = toValue(array[high]);
+	if (target >= value) return high;
+	else high--;
+	while (low <= high) {
+		i = low + ((high - low) >> 1);
+		value = toValue(array[i]);
+		if (target === value) return i;
+		if (target > value) low = i + 1;
+		else high = i - 1;
+	}
+	return low - 1;
+}
+
+export function getTerminalWidth(fallbackWidth = 200) {
+	return globalThis?.process?.stdout?.columns ?? fallbackWidth;
+}
+
+// @ts-ignore
+const isBrowser = typeof window !== "undefined" && typeof window.document !== "undefined";
+export const color = ((cfn, mfn) => ({
+	black: cfn(30),
+	red: cfn(31),
+	green: cfn(32),
+	yellow: cfn(33),
+	blue: cfn(34),
+	magenta: cfn(35),
+	cyan: cfn(36),
+	white: cfn(37),
+	grey: cfn(90),
+	bold: mfn(1, 22),
+	italic: mfn(3, 23),
+	underline: mfn(4, 24),
+	hidden: mfn(8, 28),
+	hiddenCursor: (str: string) => `\x1B[?25l${str}\x1B[?25h`,
+	unstyle: (str: string) => str.replace(/\x1B\[[0-9][0-9]?m/g, ""),
+	unstyledLength: (str: string) => str.replace(/\x1B\[[0-9][0-9]?m/g, "").length,
+	link: (str: string) => color.underline(color.blue(str)),
+}))(
+	(c1: number) => (isBrowser ? Identity : (str: string) => `\x1B[${c1}m${str.replace(/\x1B\[39m/g, `\x1B[${c1}m`)}\x1B[39m`),
+	(c1: number, c2: number) => (isBrowser ? Identity : (str: string) => `\x1B[${c1}m${str}\x1B[${c2}m`)
+);
+export function Map_get<K extends object, V>(map: WeakMap<K, V>, key: K, init: (key: K) => V): V;
+export function Map_get<K, V>(map: Map<K, V>, key: K, init: (key: K) => V): V;
+export function Map_get<K, V>(map: anymap<K, V>, key: K, init: (key: K) => V): V {
+	if (!map.has(key)) map.set(key, init(key));
+	return map.get(key)!;
+}
+export function isEmpty(array: ArrayLike<any>): boolean {
+	__DEV__: assert(isArrayLike(array));
+	return 0 === array.length;
+}
+export function Array_splice<T extends any[]>(array: T, target: T[number], index: number = array.indexOf(target)) {
+	__DEV__: {
+		const i = arguments.length === 2 ? array.indexOf(target) : index;
+		assert(i === index && i !== -1 && i === array.lastIndexOf(target), "", { array, target, index, i });
+	}
+	array.splice(index, 1);
+}
+export function Array_replace<T extends any[]>(array: T, target: T[number], ...replacements: T[number][]) {
+	const i = array.indexOf(target);
+	__DEV__: if (i === -1 || i !== array.lastIndexOf(target))
+		exit("Array_replace", { index: i, lastIndex: array.lastIndexOf(target), array, target, replacements });
+	array.splice(array.indexOf(target), 1, ...replacements);
+}
+export function has_key_defined<T extends object, K extends T extends never ? never : keyof T>(
+	o: T,
+	k: K
+): o is K extends never
+	? never
+	: T extends { [k in K]: any }
+	? T & { [k in K]: {} }
+	: T extends { [k in K]?: any }
+	? T & { [k in K]: {} }
+	: never {
+	return k in o && undefined !== o[k];
+}
+
+export function is_object(data: unknown): data is object | ({ [key: string]: unknown } | unknown[]) {
+	return "object" === typeof data && null !== data;
+}
+
+export function is_array(data: unknown): data is any[] {
+	return Array.isArray(data);
+}
+
+function ois_vobject(data: any) {
+	__DEV__: assert(is_object(data));
+	switch (data.constructor) {
+		case Array:
+		case Object:
+		case Set:
+		case Map:
+			return true;
+		default:
+			return false;
+	}
+}
+
+export function each<A extends vObject>(data: A, callback: itfn<A, void>): void;
+export function each(data: any, callback: (value: any, index: any) => void): void {
+	__DEV__: assert(ois_vobject(data));
+	// prettier-ignore
+	switch (data.constructor) {
+		case Array: { let i = 0; for (; i < data.length; i++) callback(data[i], i); return; }
+		case Object: { let k; for (k in data) callback(data[k], k); return; }
+		case Set: { let d; for (d of data) callback(d, undefined!); return; }
+		case Map: { let e; for (e of data) callback(e[1], e[0]); return; }
+		default:  { let x; for (x of data) callback(x, undefined!); return; }
+	}
+}
+
+export function iLast(index: number, array: any[]) {
+	return 1 + index === array.length;
+}
+
+export function find_last<T>(arr: T[], test: itfn<T[], boolean>): T | undefined {
+	for (var i = arr.length; --i !== -1; ) if (test(arr[i], i)) return arr[i];
+}
+
+export function try_eval<T>(fn: () => T): T | undefined {
+	try {
+		return fn();
+	} catch (e) {
+		return undefined;
+	}
+}
+
+export function clamp(min: number, max: number, value: number) {
+	return value > min ? (value < max ? value : max) : min;
+}
+
+export type MaybeFlatten<T> = T extends ReadonlyArray<infer U> ? MaybeFlatten<Exclude<U, T>> : T;
+export type FlatArray<T> = MaybeFlatten<T>[];
+export function flat<T extends readonly any[]>(arr: T): FlatArray<T> {
+	return (arr as any as [any]).flat(Infinity);
+}
+export function flatMap<T extends readonly any[], R>(arr: T, mapFn: (item: T[number], index: number, array: T) => R): FlatArray<R> {
+	return flat(arr.map(mapFn as any));
+}
+
+export function joinln(...arr: string[]): string {
+	return arr.join("\n");
+}
+
+export function join_lines(fn: () => Generator<string, void, void>): string {
+	return [...fn()].join("\n");
+}
+
+export function reduce_tagged_template<T>(args: [strings: TemplateStringsArray, ...values: T[]], map: (value: T) => string) {
+	for (var str = "" + args[0][0], i = 1; i < args.length; i++) str += map(args[i] as T) + args[0][i];
+	return str;
+}
+
+export function map_tagged_template<T, R>(args: [strings: TemplateStringsArray, ...values: T[]], map: (value: T) => R) {
+	const arr: (R | string)[] = [args[0][0]];
+	for (var i = 1; i < args.length; i++) arr.push(map(args[i] as T), args[0][i]);
+	return arr;
+}
+
+export function spliceAll<T extends any[]>(array: T): [...T] {
+	const r: [...T] = [...array];
+	array.length = 0;
+	return r;
+}
+
+export function spread<R>(fn: () => Iterable<R>): R[] {
+	return [...fn()];
+}

frontend/src/utils/prettier/plugins/rust/utils/debug.ts

@@ -0,0 +1,141 @@
+import { clamp, color, getTerminalWidth, normPath } from "./common";
+
+const cwd = 
+	typeof process === "object" && typeof process?.cwd === "function" ? /* @__PURE__ */ normPath(/* @__PURE__ */ process.cwd() ?? "") : "";
+function normPath_strip_cwd(filepath: string) {
+	let normFilePath = normPath(filepath);
+	return normFilePath.startsWith(cwd) ? normFilePath.slice(cwd.length + 1) : normFilePath;
+}
+
+type StackStyleFn = (callee: string, item: StackItem) => (str: string) => string;
+interface Stack extends Array<StackItem> {
+	message: string;
+	style?: { callee?: StackStyleFn; url?: StackStyleFn } | undefined;
+}
+
+class StackLine {
+	declare readonly raw: string;
+	declare readonly callee: string;
+	declare readonly filepath: string;
+	declare readonly line: string;
+	declare readonly col: string;
+	declare readonly other: string;
+	declare readonly url: string;
+	constructor(raw: string) {
+		({
+			1: this.callee = "",
+			2: this.filepath = "",
+			3: this.line = "",
+			4: this.col = "",
+			5: this.other = "",
+		} = (this.raw = raw).match(/at (?:(.+?)\s+\()?(?:(.+?):([0-9]+)(?::([0-9]+))?|([^)]+))\)?/) ?? ["", "", "", "", "", ""]);
+		this.url = this.filepath //
+			? normPath_strip_cwd(this.filepath) + (this.line && this.col && `:${this.line}:${this.col}`)
+			: this.other === "native"
+			? "<native>"
+			: "";
+	}
+}
+
+function getPrintWidth() {
+	return clamp(0, getTerminalWidth(128), 200) - 4;
+}
+
+class StackItem extends StackLine {
+	constructor(private readonly stack: Stack, readonly i: number, raw: string) {
+		super(raw);
+	}
+	hidden = false;
+	hide() {
+		this.hidden = true;
+		return this;
+	}
+	hideNext(n: number) {
+		for (let i = 0; i < n; i++) this.at(i)?.hide();
+	}
+	hideWhileTrue(test: (line: StackItem) => boolean) {
+		let line: StackItem | undefined = this;
+		while (line && test(line)) line = line.hide().next();
+	}
+	at(relIndex: number) {
+		return this.i + relIndex >= this.stack.length || this.i + relIndex < 0 ? undefined : this.stack[this.i + relIndex];
+	}
+	next() {
+		return this.at(+1);
+	}
+	toString() {
+		const url = this.url;
+		const calleeColor = this.stack.style?.callee?.(this.callee, this) ?? color.cyan;
+		const urlColor = this.stack.style?.url?.(url, this) ?? color.grey;
+		return compose2Cols("    at " + calleeColor(this.callee), urlColor(url), getPrintWidth());
+	}
+}
+
+// prettier-ignore
+function createStack(message: string, Error_stack: string, style: Stack["style"]): Stack {
+	for (var STACK: Stack = [] as any, i = 0, stack = Error_stack.split("\n").slice(2); i < stack.length; i++) STACK[i] = new StackItem(STACK, i, stack[i]);
+	return (STACK.message = message), (STACK.style = style), STACK;
+}
+
+function composeStack(stack: Stack) {
+	var hidden = 0;
+	var str = stack.message;
+	for (var item of stack) item.hidden ? ++hidden : (str += "\n" + item.toString());
+	return str + (hidden > 0 ? "\n" + color.grey(compose2Cols("", `...filtered ${hidden} lines`, getPrintWidth())) : "");
+}
+
+export function get_caller_cmd(offset = 0) {
+	const obj: { stack: string } = {} as any;
+	Error.captureStackTrace(obj, get_caller_cmd);
+	const lines = obj.stack.split("\n");
+	return new StackLine(lines[1 + clamp(0, lines.length - 2, offset)]).url;
+}
+
+var Error_prepareStackTrace;
+let replaced_default_prepareStackTrace = false;
+function custom_prepareStackTrace(err, calls) {
+	return (Error_prepareStackTrace?.(err, calls) ?? calls.join("\n"))?.replace(/file:\/\/\//g, "").replace(/\\\\?/g, "/") ?? calls;
+}
+
+export function overrideDefaultError(silent = false) {
+	if (replaced_default_prepareStackTrace === (replaced_default_prepareStackTrace = true)) return;
+	Error_prepareStackTrace = Error.prepareStackTrace ?? ((_, calls) => calls.join("\n"));
+	Error.prepareStackTrace = custom_prepareStackTrace;
+	if (!silent) console.log(color.grey(`[devtools] Replaced Error.prepareStackTrace at ${get_caller_cmd(1)}`));
+}
+
+export function createCustomError({
+	message = "Unknown Error",
+	editStack = (stack: StackItem[]) => {},
+	style = undefined as Stack["style"],
+	stackTraceLimit = 20,
+}): Error {
+	const _stackTraceLimit = Error.stackTraceLimit;
+	const _prepareStackTrace = Error.prepareStackTrace;
+	if (replaced_default_prepareStackTrace && _prepareStackTrace === custom_prepareStackTrace)
+		Error.prepareStackTrace = Error_prepareStackTrace;
+
+	Error.stackTraceLimit = stackTraceLimit;
+
+	const _ctx: { stack: string } = {} as any;
+
+	Error.captureStackTrace(_ctx, createCustomError);
+
+	const stack = createStack(message, _ctx.stack, style);
+	Error.prepareStackTrace = function (err, calls) {
+		editStack(stack);
+		return composeStack(stack);
+	};
+
+	const err = new Error(message); // (get) to trigger prepareStackTrace, (set) to prevent treeshaking
+	err.stack = err.stack;
+
+	Error.stackTraceLimit = _stackTraceLimit;
+	Error.prepareStackTrace = _prepareStackTrace;
+
+	return err;
+}
+
+function compose2Cols(left: string, right: string, len = 64, min = 1) {
+	return left + " ".repeat(clamp(min, len, len - (color.unstyledLength(left) + color.unstyledLength(right)))) + right;
+}

frontend/src/views/editor/extensions/codeblock/lang-parser/languages.ts

@@ -40,6 +40,8 @@ import goPrettierPlugin from "@/utils/prettier/plugins/go/go"
 import sqlPrettierPlugin from "@/utils/prettier/plugins/sql/sql"
 import phpPrettierPlugin from "@/utils/prettier/plugins/php"
 import javaPrettierPlugin from "@/utils/prettier/plugins/java"
+import xmlPrettierPlugin from "@prettier/plugin-xml"
+import * as rustPrettierPlugin from "@/utils/prettier/plugins/rust";
 import * as prettierPluginEstree from "prettier/plugins/estree";
 
 /**
@@ -91,9 +93,15 @@ export const LANGUAGES: LanguageInfo[] = [
         parser: "css",
         plugins: [cssPrettierPlugin]
     }),
-    new LanguageInfo("xml", "XML", xmlLanguage.parser),
+    new LanguageInfo("xml", "XML", xmlLanguage.parser,{
+        parser: "xml",
+        plugins: [xmlPrettierPlugin]
+    }),
     new LanguageInfo("cpp", "C++", cppLanguage.parser),
-    new LanguageInfo("rs", "Rust", rustLanguage.parser),
+    new LanguageInfo("rs", "Rust", rustLanguage.parser,{
+        parser: "jinx-rust",
+        plugins: [rustPrettierPlugin]
+    }),
     new LanguageInfo("cs", "C#", StreamLanguage.define(csharp).parser),
     new LanguageInfo("rb", "Ruby", StreamLanguage.define(ruby).parser),
     new LanguageInfo("sh", "Shell", StreamLanguage.define(shell).parser),