| /** |
| * @fileoverview enforce the location of arrow function bodies |
| * @author Sharmila Jesupaul |
| */ |
| "use strict"; |
| |
| //------------------------------------------------------------------------------ |
| // Rule Definition |
| //------------------------------------------------------------------------------ |
| module.exports = { |
| meta: { |
| docs: { |
| description: "enforce the location of arrow function bodies", |
| category: "Stylistic Issues", |
| recommended: false, |
| url: "https://eslint.org/docs/rules/implicit-arrow-linebreak" |
| }, |
| fixable: "whitespace", |
| schema: [ |
| { |
| enum: ["beside", "below"] |
| } |
| ] |
| }, |
| |
| create(context) { |
| const sourceCode = context.getSourceCode(); |
| |
| //---------------------------------------------------------------------- |
| // Helpers |
| //---------------------------------------------------------------------- |
| /** |
| * Gets the applicable preference for a particular keyword |
| * @returns {string} The applicable option for the keyword, e.g. 'beside' |
| */ |
| function getOption() { |
| return context.options[0] || "beside"; |
| } |
| |
| /** |
| * Validates the location of an arrow function body |
| * @param {ASTNode} node The arrow function body |
| * @param {string} keywordName The applicable keyword name for the arrow function body |
| * @returns {void} |
| */ |
| function validateExpression(node) { |
| const option = getOption(); |
| |
| let tokenBefore = sourceCode.getTokenBefore(node.body); |
| const hasParens = tokenBefore.value === "("; |
| |
| if (node.type === "BlockStatement") { |
| return; |
| } |
| |
| let fixerTarget = node.body; |
| |
| if (hasParens) { |
| |
| // Gets the first token before the function body that is not an open paren |
| tokenBefore = sourceCode.getTokenBefore(node.body, token => token.value !== "("); |
| fixerTarget = sourceCode.getTokenAfter(tokenBefore); |
| } |
| |
| if (tokenBefore.loc.end.line === fixerTarget.loc.start.line && option === "below") { |
| context.report({ |
| node: fixerTarget, |
| message: "Expected a linebreak before this expression.", |
| fix: fixer => fixer.insertTextBefore(fixerTarget, "\n") |
| }); |
| } else if (tokenBefore.loc.end.line !== fixerTarget.loc.start.line && option === "beside") { |
| context.report({ |
| node: fixerTarget, |
| message: "Expected no linebreak before this expression.", |
| fix: fixer => fixer.replaceTextRange([tokenBefore.range[1], fixerTarget.range[0]], " ") |
| }); |
| } |
| } |
| |
| //---------------------------------------------------------------------- |
| // Public |
| //---------------------------------------------------------------------- |
| return { |
| ArrowFunctionExpression: node => validateExpression(node) |
| }; |
| } |
| }; |