/** * @fileoverview enforce the location of arrow function bodies * @author Sharmila Jesupaul * @deprecated in ESLint v8.53.0 */ "use strict"; const { isCommentToken, isNotOpeningParenToken } = require("./utils/ast-utils"); //------------------------------------------------------------------------------ // Rule Definition //------------------------------------------------------------------------------ /** @type {import('../types').Rule.RuleModule} */ module.exports = { meta: { deprecated: { message: "Formatting rules are being moved out of ESLint core.", url: "https://eslint.org/blog/2023/10/deprecating-formatting-rules/", deprecatedSince: "8.53.0", availableUntil: "10.0.0", replacedBy: [ { message: "ESLint Stylistic now maintains deprecated stylistic core rules.", url: "https://eslint.style/guide/migration", plugin: { name: "@stylistic/eslint-plugin-js", url: "https://eslint.style/packages/js", }, rule: { name: "implicit-arrow-linebreak", url: "https://eslint.style/rules/js/implicit-arrow-linebreak", }, }, ], }, type: "layout", docs: { description: "Enforce the location of arrow function bodies", recommended: false, url: "https://eslint.org/docs/latest/rules/implicit-arrow-linebreak", }, fixable: "whitespace", schema: [ { enum: ["beside", "below"], }, ], messages: { expected: "Expected a linebreak before this expression.", unexpected: "Expected no linebreak before this expression.", }, }, create(context) { const sourceCode = context.sourceCode; const option = context.options[0] || "beside"; /** * Validates the location of an arrow function body * @param {ASTNode} node The arrow function body * @returns {void} */ function validateExpression(node) { if (node.body.type === "BlockStatement") { return; } const arrowToken = sourceCode.getTokenBefore( node.body, isNotOpeningParenToken, ); const firstTokenOfBody = sourceCode.getTokenAfter(arrowToken); if ( arrowToken.loc.end.line === firstTokenOfBody.loc.start.line && option === "below" ) { context.report({ node: firstTokenOfBody, messageId: "expected", fix: fixer => fixer.insertTextBefore(firstTokenOfBody, "\n"), }); } else if ( arrowToken.loc.end.line !== firstTokenOfBody.loc.start.line && option === "beside" ) { context.report({ node: firstTokenOfBody, messageId: "unexpected", fix(fixer) { if ( sourceCode.getFirstTokenBetween( arrowToken, firstTokenOfBody, { includeComments: true, filter: isCommentToken, }, ) ) { return null; } return fixer.replaceTextRange( [arrowToken.range[1], firstTokenOfBody.range[0]], " ", ); }, }); } } //---------------------------------------------------------------------- // Public //---------------------------------------------------------------------- return { ArrowFunctionExpression: node => validateExpression(node), }; }, };