diff options
Diffstat (limited to 'tools/node_modules/eslint/lib/rules/dot-notation.js')
-rw-r--r-- | tools/node_modules/eslint/lib/rules/dot-notation.js | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/tools/node_modules/eslint/lib/rules/dot-notation.js b/tools/node_modules/eslint/lib/rules/dot-notation.js new file mode 100644 index 0000000000..21e3df1741 --- /dev/null +++ b/tools/node_modules/eslint/lib/rules/dot-notation.js @@ -0,0 +1,159 @@ +/** + * @fileoverview Rule to warn about using dot notation instead of square bracket notation when possible. + * @author Josh Perez + */ +"use strict"; + +//------------------------------------------------------------------------------ +// Requirements +//------------------------------------------------------------------------------ + +const astUtils = require("../ast-utils"); + +//------------------------------------------------------------------------------ +// Rule Definition +//------------------------------------------------------------------------------ + +const validIdentifier = /^[a-zA-Z_$][a-zA-Z0-9_$]*$/; +const keywords = require("../util/keywords"); + +module.exports = { + meta: { + docs: { + description: "enforce dot notation whenever possible", + category: "Best Practices", + recommended: false + }, + + schema: [ + { + type: "object", + properties: { + allowKeywords: { + type: "boolean" + }, + allowPattern: { + type: "string" + } + }, + additionalProperties: false + } + ], + + fixable: "code" + }, + + create(context) { + const options = context.options[0] || {}; + const allowKeywords = options.allowKeywords === void 0 || !!options.allowKeywords; + const sourceCode = context.getSourceCode(); + + let allowPattern; + + if (options.allowPattern) { + allowPattern = new RegExp(options.allowPattern); + } + + /** + * Check if the property is valid dot notation + * @param {ASTNode} node The dot notation node + * @param {string} value Value which is to be checked + * @returns {void} + */ + function checkComputedProperty(node, value) { + if ( + validIdentifier.test(value) && + (allowKeywords || keywords.indexOf(String(value)) === -1) && + !(allowPattern && allowPattern.test(value)) + ) { + const formattedValue = node.property.type === "Literal" ? JSON.stringify(value) : `\`${value}\``; + + context.report({ + node: node.property, + message: "[{{propertyValue}}] is better written in dot notation.", + data: { + propertyValue: formattedValue + }, + fix(fixer) { + const leftBracket = sourceCode.getTokenAfter(node.object, astUtils.isOpeningBracketToken); + const rightBracket = sourceCode.getLastToken(node); + + if (sourceCode.getFirstTokenBetween(leftBracket, rightBracket, { includeComments: true, filter: astUtils.isCommentToken })) { + + // Don't perform any fixes if there are comments inside the brackets. + return null; + } + + const tokenAfterProperty = sourceCode.getTokenAfter(rightBracket); + const needsSpaceAfterProperty = tokenAfterProperty && + rightBracket.range[1] === tokenAfterProperty.range[0] && + !astUtils.canTokensBeAdjacent(String(value), tokenAfterProperty); + + const textBeforeDot = astUtils.isDecimalInteger(node.object) ? " " : ""; + const textAfterProperty = needsSpaceAfterProperty ? " " : ""; + + return fixer.replaceTextRange( + [leftBracket.range[0], rightBracket.range[1]], + `${textBeforeDot}.${value}${textAfterProperty}` + ); + } + }); + } + } + + return { + MemberExpression(node) { + if ( + node.computed && + node.property.type === "Literal" + ) { + checkComputedProperty(node, node.property.value); + } + if ( + node.computed && + node.property.type === "TemplateLiteral" && + node.property.expressions.length === 0 + ) { + checkComputedProperty(node, node.property.quasis[0].value.cooked); + } + if ( + !allowKeywords && + !node.computed && + keywords.indexOf(String(node.property.name)) !== -1 + ) { + context.report({ + node: node.property, + message: ".{{propertyName}} is a syntax error.", + data: { + propertyName: node.property.name + }, + fix(fixer) { + const dot = sourceCode.getTokenBefore(node.property); + const textAfterDot = sourceCode.text.slice(dot.range[1], node.property.range[0]); + + if (textAfterDot.trim()) { + + // Don't perform any fixes if there are comments between the dot and the property name. + return null; + } + + if (node.object.type === "Identifier" && node.object.name === "let") { + + /* + * A statement that starts with `let[` is parsed as a destructuring variable declaration, not + * a MemberExpression. + */ + return null; + } + + return fixer.replaceTextRange( + [dot.range[0], node.property.range[1]], + `[${textAfterDot}"${node.property.name}"]` + ); + } + }); + } + } + }; + } +}; |