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Diffstat (limited to 'tools/node_modules/eslint/lib/rules/arrow-parens.js')
-rw-r--r-- | tools/node_modules/eslint/lib/rules/arrow-parens.js | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/tools/node_modules/eslint/lib/rules/arrow-parens.js b/tools/node_modules/eslint/lib/rules/arrow-parens.js new file mode 100644 index 0000000000..e8f8ddd8e7 --- /dev/null +++ b/tools/node_modules/eslint/lib/rules/arrow-parens.js @@ -0,0 +1,156 @@ +/** + * @fileoverview Rule to require parens in arrow function arguments. + * @author Jxck + */ +"use strict"; + +//------------------------------------------------------------------------------ +// Requirements +//------------------------------------------------------------------------------ + +const astUtils = require("../ast-utils"); + +//------------------------------------------------------------------------------ +// Rule Definition +//------------------------------------------------------------------------------ + +module.exports = { + meta: { + docs: { + description: "require parentheses around arrow function arguments", + category: "ECMAScript 6", + recommended: false + }, + + fixable: "code", + + schema: [ + { + enum: ["always", "as-needed"] + }, + { + type: "object", + properties: { + requireForBlockBody: { + type: "boolean" + } + }, + additionalProperties: false + } + ] + }, + + create(context) { + const message = "Expected parentheses around arrow function argument."; + const asNeededMessage = "Unexpected parentheses around single function argument."; + const asNeeded = context.options[0] === "as-needed"; + const requireForBlockBodyMessage = "Unexpected parentheses around single function argument having a body with no curly braces"; + const requireForBlockBodyNoParensMessage = "Expected parentheses around arrow function argument having a body with curly braces."; + const requireForBlockBody = asNeeded && context.options[1] && context.options[1].requireForBlockBody === true; + + const sourceCode = context.getSourceCode(); + + /** + * Determines whether a arrow function argument end with `)` + * @param {ASTNode} node The arrow function node. + * @returns {void} + */ + function parens(node) { + const isAsync = node.async; + const firstTokenOfParam = sourceCode.getFirstToken(node, isAsync ? 1 : 0); + + /** + * Remove the parenthesis around a parameter + * @param {Fixer} fixer Fixer + * @returns {string} fixed parameter + */ + function fixParamsWithParenthesis(fixer) { + const paramToken = sourceCode.getTokenAfter(firstTokenOfParam); + + /* + * ES8 allows Trailing commas in function parameter lists and calls + * https://github.com/eslint/eslint/issues/8834 + */ + const closingParenToken = sourceCode.getTokenAfter(paramToken, astUtils.isClosingParenToken); + const asyncToken = isAsync ? sourceCode.getTokenBefore(firstTokenOfParam) : null; + const shouldAddSpaceForAsync = asyncToken && (asyncToken.range[1] === firstTokenOfParam.range[0]); + + return fixer.replaceTextRange([ + firstTokenOfParam.range[0], + closingParenToken.range[1] + ], `${shouldAddSpaceForAsync ? " " : ""}${paramToken.value}`); + } + + // "as-needed", { "requireForBlockBody": true }: x => x + if ( + requireForBlockBody && + node.params.length === 1 && + node.params[0].type === "Identifier" && + !node.params[0].typeAnnotation && + node.body.type !== "BlockStatement" && + !node.returnType + ) { + if (astUtils.isOpeningParenToken(firstTokenOfParam)) { + context.report({ + node, + message: requireForBlockBodyMessage, + fix: fixParamsWithParenthesis + }); + } + return; + } + + if ( + requireForBlockBody && + node.body.type === "BlockStatement" + ) { + if (!astUtils.isOpeningParenToken(firstTokenOfParam)) { + context.report({ + node, + message: requireForBlockBodyNoParensMessage, + fix(fixer) { + return fixer.replaceText(firstTokenOfParam, `(${firstTokenOfParam.value})`); + } + }); + } + return; + } + + // "as-needed": x => x + if (asNeeded && + node.params.length === 1 && + node.params[0].type === "Identifier" && + !node.params[0].typeAnnotation && + !node.returnType + ) { + if (astUtils.isOpeningParenToken(firstTokenOfParam)) { + context.report({ + node, + message: asNeededMessage, + fix: fixParamsWithParenthesis + }); + } + return; + } + + if (firstTokenOfParam.type === "Identifier") { + const after = sourceCode.getTokenAfter(firstTokenOfParam); + + // (x) => x + if (after.value !== ")") { + context.report({ + node, + message, + fix(fixer) { + return fixer.replaceText(firstTokenOfParam, `(${firstTokenOfParam.value})`); + } + }); + } + } + } + + return { + ArrowFunctionExpression: parens + }; + } +}; |