| /** |
| * @fileoverview Common utils for AST. |
| * @author Gyandeep Singh |
| */ |
| |
| "use strict"; |
| |
| //------------------------------------------------------------------------------ |
| // Requirements |
| //------------------------------------------------------------------------------ |
| |
| const esutils = require("esutils"); |
| const espree = require("espree"); |
| const lodash = require("lodash"); |
| const { |
| breakableTypePattern, |
| createGlobalLinebreakMatcher, |
| lineBreakPattern, |
| shebangPattern |
| } = require("../../shared/ast-utils"); |
| |
| //------------------------------------------------------------------------------ |
| // Helpers |
| //------------------------------------------------------------------------------ |
| |
| const anyFunctionPattern = /^(?:Function(?:Declaration|Expression)|ArrowFunctionExpression)$/u; |
| const anyLoopPattern = /^(?:DoWhile|For|ForIn|ForOf|While)Statement$/u; |
| const arrayOrTypedArrayPattern = /Array$/u; |
| const arrayMethodPattern = /^(?:every|filter|find|findIndex|forEach|map|some)$/u; |
| const bindOrCallOrApplyPattern = /^(?:bind|call|apply)$/u; |
| const thisTagPattern = /^[\s*]*@this/mu; |
| |
| |
| const COMMENTS_IGNORE_PATTERN = /^\s*(?:eslint|jshint\s+|jslint\s+|istanbul\s+|globals?\s+|exported\s+|jscs)/u; |
| const LINEBREAKS = new Set(["\r\n", "\r", "\n", "\u2028", "\u2029"]); |
| |
| // A set of node types that can contain a list of statements |
| const STATEMENT_LIST_PARENTS = new Set(["Program", "BlockStatement", "SwitchCase"]); |
| |
| /** |
| * Checks reference if is non initializer and writable. |
| * @param {Reference} reference - A reference to check. |
| * @param {int} index - The index of the reference in the references. |
| * @param {Reference[]} references - The array that the reference belongs to. |
| * @returns {boolean} Success/Failure |
| * @private |
| */ |
| function isModifyingReference(reference, index, references) { |
| const identifier = reference.identifier; |
| |
| /* |
| * Destructuring assignments can have multiple default value, so |
| * possibly there are multiple writeable references for the same |
| * identifier. |
| */ |
| const modifyingDifferentIdentifier = index === 0 || |
| references[index - 1].identifier !== identifier; |
| |
| return (identifier && |
| reference.init === false && |
| reference.isWrite() && |
| modifyingDifferentIdentifier |
| ); |
| } |
| |
| /** |
| * Checks whether the given string starts with uppercase or not. |
| * |
| * @param {string} s - The string to check. |
| * @returns {boolean} `true` if the string starts with uppercase. |
| */ |
| function startsWithUpperCase(s) { |
| return s[0] !== s[0].toLocaleLowerCase(); |
| } |
| |
| /** |
| * Checks whether or not a node is a constructor. |
| * @param {ASTNode} node - A function node to check. |
| * @returns {boolean} Wehether or not a node is a constructor. |
| */ |
| function isES5Constructor(node) { |
| return (node.id && startsWithUpperCase(node.id.name)); |
| } |
| |
| /** |
| * Finds a function node from ancestors of a node. |
| * @param {ASTNode} node - A start node to find. |
| * @returns {Node|null} A found function node. |
| */ |
| function getUpperFunction(node) { |
| for (let currentNode = node; currentNode; currentNode = currentNode.parent) { |
| if (anyFunctionPattern.test(currentNode.type)) { |
| return currentNode; |
| } |
| } |
| return null; |
| } |
| |
| /** |
| * Checks whether a given node is a function node or not. |
| * The following types are function nodes: |
| * |
| * - ArrowFunctionExpression |
| * - FunctionDeclaration |
| * - FunctionExpression |
| * |
| * @param {ASTNode|null} node - A node to check. |
| * @returns {boolean} `true` if the node is a function node. |
| */ |
| function isFunction(node) { |
| return Boolean(node && anyFunctionPattern.test(node.type)); |
| } |
| |
| /** |
| * Checks whether a given node is a loop node or not. |
| * The following types are loop nodes: |
| * |
| * - DoWhileStatement |
| * - ForInStatement |
| * - ForOfStatement |
| * - ForStatement |
| * - WhileStatement |
| * |
| * @param {ASTNode|null} node - A node to check. |
| * @returns {boolean} `true` if the node is a loop node. |
| */ |
| function isLoop(node) { |
| return Boolean(node && anyLoopPattern.test(node.type)); |
| } |
| |
| /** |
| * Checks whether the given node is in a loop or not. |
| * |
| * @param {ASTNode} node - The node to check. |
| * @returns {boolean} `true` if the node is in a loop. |
| */ |
| function isInLoop(node) { |
| for (let currentNode = node; currentNode && !isFunction(currentNode); currentNode = currentNode.parent) { |
| if (isLoop(currentNode)) { |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| /** |
| * Checks whether or not a node is `null` or `undefined`. |
| * @param {ASTNode} node - A node to check. |
| * @returns {boolean} Whether or not the node is a `null` or `undefined`. |
| * @public |
| */ |
| function isNullOrUndefined(node) { |
| return ( |
| module.exports.isNullLiteral(node) || |
| (node.type === "Identifier" && node.name === "undefined") || |
| (node.type === "UnaryExpression" && node.operator === "void") |
| ); |
| } |
| |
| /** |
| * Checks whether or not a node is callee. |
| * @param {ASTNode} node - A node to check. |
| * @returns {boolean} Whether or not the node is callee. |
| */ |
| function isCallee(node) { |
| return node.parent.type === "CallExpression" && node.parent.callee === node; |
| } |
| |
| /** |
| * Checks whether or not a node is `Reflect.apply`. |
| * @param {ASTNode} node - A node to check. |
| * @returns {boolean} Whether or not the node is a `Reflect.apply`. |
| */ |
| function isReflectApply(node) { |
| return ( |
| node.type === "MemberExpression" && |
| node.object.type === "Identifier" && |
| node.object.name === "Reflect" && |
| node.property.type === "Identifier" && |
| node.property.name === "apply" && |
| node.computed === false |
| ); |
| } |
| |
| /** |
| * Checks whether or not a node is `Array.from`. |
| * @param {ASTNode} node - A node to check. |
| * @returns {boolean} Whether or not the node is a `Array.from`. |
| */ |
| function isArrayFromMethod(node) { |
| return ( |
| node.type === "MemberExpression" && |
| node.object.type === "Identifier" && |
| arrayOrTypedArrayPattern.test(node.object.name) && |
| node.property.type === "Identifier" && |
| node.property.name === "from" && |
| node.computed === false |
| ); |
| } |
| |
| /** |
| * Checks whether or not a node is a method which has `thisArg`. |
| * @param {ASTNode} node - A node to check. |
| * @returns {boolean} Whether or not the node is a method which has `thisArg`. |
| */ |
| function isMethodWhichHasThisArg(node) { |
| for ( |
| let currentNode = node; |
| currentNode.type === "MemberExpression" && !currentNode.computed; |
| currentNode = currentNode.property |
| ) { |
| if (currentNode.property.type === "Identifier") { |
| return arrayMethodPattern.test(currentNode.property.name); |
| } |
| } |
| |
| return false; |
| } |
| |
| /** |
| * Creates the negate function of the given function. |
| * @param {Function} f - The function to negate. |
| * @returns {Function} Negated function. |
| */ |
| function negate(f) { |
| return token => !f(token); |
| } |
| |
| /** |
| * Checks whether or not a node has a `@this` tag in its comments. |
| * @param {ASTNode} node - A node to check. |
| * @param {SourceCode} sourceCode - A SourceCode instance to get comments. |
| * @returns {boolean} Whether or not the node has a `@this` tag in its comments. |
| */ |
| function hasJSDocThisTag(node, sourceCode) { |
| const jsdocComment = sourceCode.getJSDocComment(node); |
| |
| if (jsdocComment && thisTagPattern.test(jsdocComment.value)) { |
| return true; |
| } |
| |
| // Checks `@this` in its leading comments for callbacks, |
| // because callbacks don't have its JSDoc comment. |
| // e.g. |
| // sinon.test(/* @this sinon.Sandbox */function() { this.spy(); }); |
| return sourceCode.getCommentsBefore(node).some(comment => thisTagPattern.test(comment.value)); |
| } |
| |
| /** |
| * Determines if a node is surrounded by parentheses. |
| * @param {SourceCode} sourceCode The ESLint source code object |
| * @param {ASTNode} node The node to be checked. |
| * @returns {boolean} True if the node is parenthesised. |
| * @private |
| */ |
| function isParenthesised(sourceCode, node) { |
| const previousToken = sourceCode.getTokenBefore(node), |
| nextToken = sourceCode.getTokenAfter(node); |
| |
| return Boolean(previousToken && nextToken) && |
| previousToken.value === "(" && previousToken.range[1] <= node.range[0] && |
| nextToken.value === ")" && nextToken.range[0] >= node.range[1]; |
| } |
| |
| /** |
| * Checks if the given token is an arrow token or not. |
| * |
| * @param {Token} token - The token to check. |
| * @returns {boolean} `true` if the token is an arrow token. |
| */ |
| function isArrowToken(token) { |
| return token.value === "=>" && token.type === "Punctuator"; |
| } |
| |
| /** |
| * Checks if the given token is a comma token or not. |
| * |
| * @param {Token} token - The token to check. |
| * @returns {boolean} `true` if the token is a comma token. |
| */ |
| function isCommaToken(token) { |
| return token.value === "," && token.type === "Punctuator"; |
| } |
| |
| /** |
| * Checks if the given token is a semicolon token or not. |
| * |
| * @param {Token} token - The token to check. |
| * @returns {boolean} `true` if the token is a semicolon token. |
| */ |
| function isSemicolonToken(token) { |
| return token.value === ";" && token.type === "Punctuator"; |
| } |
| |
| /** |
| * Checks if the given token is a colon token or not. |
| * |
| * @param {Token} token - The token to check. |
| * @returns {boolean} `true` if the token is a colon token. |
| */ |
| function isColonToken(token) { |
| return token.value === ":" && token.type === "Punctuator"; |
| } |
| |
| /** |
| * Checks if the given token is an opening parenthesis token or not. |
| * |
| * @param {Token} token - The token to check. |
| * @returns {boolean} `true` if the token is an opening parenthesis token. |
| */ |
| function isOpeningParenToken(token) { |
| return token.value === "(" && token.type === "Punctuator"; |
| } |
| |
| /** |
| * Checks if the given token is a closing parenthesis token or not. |
| * |
| * @param {Token} token - The token to check. |
| * @returns {boolean} `true` if the token is a closing parenthesis token. |
| */ |
| function isClosingParenToken(token) { |
| return token.value === ")" && token.type === "Punctuator"; |
| } |
| |
| /** |
| * Checks if the given token is an opening square bracket token or not. |
| * |
| * @param {Token} token - The token to check. |
| * @returns {boolean} `true` if the token is an opening square bracket token. |
| */ |
| function isOpeningBracketToken(token) { |
| return token.value === "[" && token.type === "Punctuator"; |
| } |
| |
| /** |
| * Checks if the given token is a closing square bracket token or not. |
| * |
| * @param {Token} token - The token to check. |
| * @returns {boolean} `true` if the token is a closing square bracket token. |
| */ |
| function isClosingBracketToken(token) { |
| return token.value === "]" && token.type === "Punctuator"; |
| } |
| |
| /** |
| * Checks if the given token is an opening brace token or not. |
| * |
| * @param {Token} token - The token to check. |
| * @returns {boolean} `true` if the token is an opening brace token. |
| */ |
| function isOpeningBraceToken(token) { |
| return token.value === "{" && token.type === "Punctuator"; |
| } |
| |
| /** |
| * Checks if the given token is a closing brace token or not. |
| * |
| * @param {Token} token - The token to check. |
| * @returns {boolean} `true` if the token is a closing brace token. |
| */ |
| function isClosingBraceToken(token) { |
| return token.value === "}" && token.type === "Punctuator"; |
| } |
| |
| /** |
| * Checks if the given token is a comment token or not. |
| * |
| * @param {Token} token - The token to check. |
| * @returns {boolean} `true` if the token is a comment token. |
| */ |
| function isCommentToken(token) { |
| return token.type === "Line" || token.type === "Block" || token.type === "Shebang"; |
| } |
| |
| /** |
| * Checks if the given token is a keyword token or not. |
| * |
| * @param {Token} token - The token to check. |
| * @returns {boolean} `true` if the token is a keyword token. |
| */ |
| function isKeywordToken(token) { |
| return token.type === "Keyword"; |
| } |
| |
| /** |
| * Gets the `(` token of the given function node. |
| * |
| * @param {ASTNode} node - The function node to get. |
| * @param {SourceCode} sourceCode - The source code object to get tokens. |
| * @returns {Token} `(` token. |
| */ |
| function getOpeningParenOfParams(node, sourceCode) { |
| return node.id |
| ? sourceCode.getTokenAfter(node.id, isOpeningParenToken) |
| : sourceCode.getFirstToken(node, isOpeningParenToken); |
| } |
| |
| /** |
| * Checks whether or not the tokens of two given nodes are same. |
| * @param {ASTNode} left - A node 1 to compare. |
| * @param {ASTNode} right - A node 2 to compare. |
| * @param {SourceCode} sourceCode - The ESLint source code object. |
| * @returns {boolean} the source code for the given node. |
| */ |
| function equalTokens(left, right, sourceCode) { |
| const tokensL = sourceCode.getTokens(left); |
| const tokensR = sourceCode.getTokens(right); |
| |
| if (tokensL.length !== tokensR.length) { |
| return false; |
| } |
| for (let i = 0; i < tokensL.length; ++i) { |
| if (tokensL[i].type !== tokensR[i].type || |
| tokensL[i].value !== tokensR[i].value |
| ) { |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| //------------------------------------------------------------------------------ |
| // Public Interface |
| //------------------------------------------------------------------------------ |
| |
| module.exports = { |
| COMMENTS_IGNORE_PATTERN, |
| LINEBREAKS, |
| LINEBREAK_MATCHER: lineBreakPattern, |
| SHEBANG_MATCHER: shebangPattern, |
| STATEMENT_LIST_PARENTS, |
| |
| /** |
| * Determines whether two adjacent tokens are on the same line. |
| * @param {Object} left - The left token object. |
| * @param {Object} right - The right token object. |
| * @returns {boolean} Whether or not the tokens are on the same line. |
| * @public |
| */ |
| isTokenOnSameLine(left, right) { |
| return left.loc.end.line === right.loc.start.line; |
| }, |
| |
| isNullOrUndefined, |
| isCallee, |
| isES5Constructor, |
| getUpperFunction, |
| isFunction, |
| isLoop, |
| isInLoop, |
| isArrayFromMethod, |
| isParenthesised, |
| createGlobalLinebreakMatcher, |
| equalTokens, |
| |
| isArrowToken, |
| isClosingBraceToken, |
| isClosingBracketToken, |
| isClosingParenToken, |
| isColonToken, |
| isCommaToken, |
| isCommentToken, |
| isKeywordToken, |
| isNotClosingBraceToken: negate(isClosingBraceToken), |
| isNotClosingBracketToken: negate(isClosingBracketToken), |
| isNotClosingParenToken: negate(isClosingParenToken), |
| isNotColonToken: negate(isColonToken), |
| isNotCommaToken: negate(isCommaToken), |
| isNotOpeningBraceToken: negate(isOpeningBraceToken), |
| isNotOpeningBracketToken: negate(isOpeningBracketToken), |
| isNotOpeningParenToken: negate(isOpeningParenToken), |
| isNotSemicolonToken: negate(isSemicolonToken), |
| isOpeningBraceToken, |
| isOpeningBracketToken, |
| isOpeningParenToken, |
| isSemicolonToken, |
| |
| /** |
| * Checks whether or not a given node is a string literal. |
| * @param {ASTNode} node - A node to check. |
| * @returns {boolean} `true` if the node is a string literal. |
| */ |
| isStringLiteral(node) { |
| return ( |
| (node.type === "Literal" && typeof node.value === "string") || |
| node.type === "TemplateLiteral" |
| ); |
| }, |
| |
| /** |
| * Checks whether a given node is a breakable statement or not. |
| * The node is breakable if the node is one of the following type: |
| * |
| * - DoWhileStatement |
| * - ForInStatement |
| * - ForOfStatement |
| * - ForStatement |
| * - SwitchStatement |
| * - WhileStatement |
| * |
| * @param {ASTNode} node - A node to check. |
| * @returns {boolean} `true` if the node is breakable. |
| */ |
| isBreakableStatement(node) { |
| return breakableTypePattern.test(node.type); |
| }, |
| |
| /** |
| * Gets references which are non initializer and writable. |
| * @param {Reference[]} references - An array of references. |
| * @returns {Reference[]} An array of only references which are non initializer and writable. |
| * @public |
| */ |
| getModifyingReferences(references) { |
| return references.filter(isModifyingReference); |
| }, |
| |
| /** |
| * Validate that a string passed in is surrounded by the specified character |
| * @param {string} val The text to check. |
| * @param {string} character The character to see if it's surrounded by. |
| * @returns {boolean} True if the text is surrounded by the character, false if not. |
| * @private |
| */ |
| isSurroundedBy(val, character) { |
| return val[0] === character && val[val.length - 1] === character; |
| }, |
| |
| /** |
| * Returns whether the provided node is an ESLint directive comment or not |
| * @param {Line|Block} node The comment token to be checked |
| * @returns {boolean} `true` if the node is an ESLint directive comment |
| */ |
| isDirectiveComment(node) { |
| const comment = node.value.trim(); |
| |
| return ( |
| node.type === "Line" && comment.indexOf("eslint-") === 0 || |
| node.type === "Block" && ( |
| comment.indexOf("global ") === 0 || |
| comment.indexOf("eslint ") === 0 || |
| comment.indexOf("eslint-") === 0 |
| ) |
| ); |
| }, |
| |
| /** |
| * Gets the trailing statement of a given node. |
| * |
| * if (code) |
| * consequent; |
| * |
| * When taking this `IfStatement`, returns `consequent;` statement. |
| * |
| * @param {ASTNode} A node to get. |
| * @returns {ASTNode|null} The trailing statement's node. |
| */ |
| getTrailingStatement: esutils.ast.trailingStatement, |
| |
| /** |
| * Finds the variable by a given name in a given scope and its upper scopes. |
| * |
| * @param {eslint-scope.Scope} initScope - A scope to start find. |
| * @param {string} name - A variable name to find. |
| * @returns {eslint-scope.Variable|null} A found variable or `null`. |
| */ |
| getVariableByName(initScope, name) { |
| let scope = initScope; |
| |
| while (scope) { |
| const variable = scope.set.get(name); |
| |
| if (variable) { |
| return variable; |
| } |
| |
| scope = scope.upper; |
| } |
| |
| return null; |
| }, |
| |
| /** |
| * Checks whether or not a given function node is the default `this` binding. |
| * |
| * First, this checks the node: |
| * |
| * - The function name does not start with uppercase (it's a constructor). |
| * - The function does not have a JSDoc comment that has a @this tag. |
| * |
| * Next, this checks the location of the node. |
| * If the location is below, this judges `this` is valid. |
| * |
| * - The location is not on an object literal. |
| * - The location is not assigned to a variable which starts with an uppercase letter. |
| * - The location is not on an ES2015 class. |
| * - Its `bind`/`call`/`apply` method is not called directly. |
| * - The function is not a callback of array methods (such as `.forEach()`) if `thisArg` is given. |
| * |
| * @param {ASTNode} node - A function node to check. |
| * @param {SourceCode} sourceCode - A SourceCode instance to get comments. |
| * @returns {boolean} The function node is the default `this` binding. |
| */ |
| isDefaultThisBinding(node, sourceCode) { |
| if (isES5Constructor(node) || hasJSDocThisTag(node, sourceCode)) { |
| return false; |
| } |
| const isAnonymous = node.id === null; |
| let currentNode = node; |
| |
| while (currentNode) { |
| const parent = currentNode.parent; |
| |
| switch (parent.type) { |
| |
| /* |
| * Looks up the destination. |
| * e.g., obj.foo = nativeFoo || function foo() { ... }; |
| */ |
| case "LogicalExpression": |
| case "ConditionalExpression": |
| currentNode = parent; |
| break; |
| |
| /* |
| * If the upper function is IIFE, checks the destination of the return value. |
| * e.g. |
| * obj.foo = (function() { |
| * // setup... |
| * return function foo() { ... }; |
| * })(); |
| * obj.foo = (() => |
| * function foo() { ... } |
| * )(); |
| */ |
| case "ReturnStatement": { |
| const func = getUpperFunction(parent); |
| |
| if (func === null || !isCallee(func)) { |
| return true; |
| } |
| currentNode = func.parent; |
| break; |
| } |
| case "ArrowFunctionExpression": |
| if (currentNode !== parent.body || !isCallee(parent)) { |
| return true; |
| } |
| currentNode = parent.parent; |
| break; |
| |
| /* |
| * e.g. |
| * var obj = { foo() { ... } }; |
| * var obj = { foo: function() { ... } }; |
| * class A { constructor() { ... } } |
| * class A { foo() { ... } } |
| * class A { get foo() { ... } } |
| * class A { set foo() { ... } } |
| * class A { static foo() { ... } } |
| */ |
| case "Property": |
| case "MethodDefinition": |
| return parent.value !== currentNode; |
| |
| /* |
| * e.g. |
| * obj.foo = function foo() { ... }; |
| * Foo = function() { ... }; |
| * [obj.foo = function foo() { ... }] = a; |
| * [Foo = function() { ... }] = a; |
| */ |
| case "AssignmentExpression": |
| case "AssignmentPattern": |
| if (parent.left.type === "MemberExpression") { |
| return false; |
| } |
| if ( |
| isAnonymous && |
| parent.left.type === "Identifier" && |
| startsWithUpperCase(parent.left.name) |
| ) { |
| return false; |
| } |
| return true; |
| |
| /* |
| * e.g. |
| * var Foo = function() { ... }; |
| */ |
| case "VariableDeclarator": |
| return !( |
| isAnonymous && |
| parent.init === currentNode && |
| parent.id.type === "Identifier" && |
| startsWithUpperCase(parent.id.name) |
| ); |
| |
| /* |
| * e.g. |
| * var foo = function foo() { ... }.bind(obj); |
| * (function foo() { ... }).call(obj); |
| * (function foo() { ... }).apply(obj, []); |
| */ |
| case "MemberExpression": |
| return ( |
| parent.object !== currentNode || |
| parent.property.type !== "Identifier" || |
| !bindOrCallOrApplyPattern.test(parent.property.name) || |
| !isCallee(parent) || |
| parent.parent.arguments.length === 0 || |
| isNullOrUndefined(parent.parent.arguments[0]) |
| ); |
| |
| /* |
| * e.g. |
| * Reflect.apply(function() {}, obj, []); |
| * Array.from([], function() {}, obj); |
| * list.forEach(function() {}, obj); |
| */ |
| case "CallExpression": |
| if (isReflectApply(parent.callee)) { |
| return ( |
| parent.arguments.length !== 3 || |
| parent.arguments[0] !== currentNode || |
| isNullOrUndefined(parent.arguments[1]) |
| ); |
| } |
| if (isArrayFromMethod(parent.callee)) { |
| return ( |
| parent.arguments.length !== 3 || |
| parent.arguments[1] !== currentNode || |
| isNullOrUndefined(parent.arguments[2]) |
| ); |
| } |
| if (isMethodWhichHasThisArg(parent.callee)) { |
| return ( |
| parent.arguments.length !== 2 || |
| parent.arguments[0] !== currentNode || |
| isNullOrUndefined(parent.arguments[1]) |
| ); |
| } |
| return true; |
| |
| // Otherwise `this` is default. |
| default: |
| return true; |
| } |
| } |
| |
| /* istanbul ignore next */ |
| return true; |
| }, |
| |
| /** |
| * Get the precedence level based on the node type |
| * @param {ASTNode} node node to evaluate |
| * @returns {int} precedence level |
| * @private |
| */ |
| getPrecedence(node) { |
| switch (node.type) { |
| case "SequenceExpression": |
| return 0; |
| |
| case "AssignmentExpression": |
| case "ArrowFunctionExpression": |
| case "YieldExpression": |
| return 1; |
| |
| case "ConditionalExpression": |
| return 3; |
| |
| case "LogicalExpression": |
| switch (node.operator) { |
| case "||": |
| return 4; |
| case "&&": |
| return 5; |
| |
| // no default |
| } |
| |
| /* falls through */ |
| |
| case "BinaryExpression": |
| |
| switch (node.operator) { |
| case "|": |
| return 6; |
| case "^": |
| return 7; |
| case "&": |
| return 8; |
| case "==": |
| case "!=": |
| case "===": |
| case "!==": |
| return 9; |
| case "<": |
| case "<=": |
| case ">": |
| case ">=": |
| case "in": |
| case "instanceof": |
| return 10; |
| case "<<": |
| case ">>": |
| case ">>>": |
| return 11; |
| case "+": |
| case "-": |
| return 12; |
| case "*": |
| case "/": |
| case "%": |
| return 13; |
| case "**": |
| return 15; |
| |
| // no default |
| } |
| |
| /* falls through */ |
| |
| case "UnaryExpression": |
| case "AwaitExpression": |
| return 16; |
| |
| case "UpdateExpression": |
| return 17; |
| |
| case "CallExpression": |
| return 18; |
| |
| case "NewExpression": |
| return 19; |
| |
| default: |
| return 20; |
| } |
| }, |
| |
| /** |
| * Checks whether the given node is an empty block node or not. |
| * |
| * @param {ASTNode|null} node - The node to check. |
| * @returns {boolean} `true` if the node is an empty block. |
| */ |
| isEmptyBlock(node) { |
| return Boolean(node && node.type === "BlockStatement" && node.body.length === 0); |
| }, |
| |
| /** |
| * Checks whether the given node is an empty function node or not. |
| * |
| * @param {ASTNode|null} node - The node to check. |
| * @returns {boolean} `true` if the node is an empty function. |
| */ |
| isEmptyFunction(node) { |
| return isFunction(node) && module.exports.isEmptyBlock(node.body); |
| }, |
| |
| /** |
| * Gets the property name of a given node. |
| * The node can be a MemberExpression, a Property, or a MethodDefinition. |
| * |
| * If the name is dynamic, this returns `null`. |
| * |
| * For examples: |
| * |
| * a.b // => "b" |
| * a["b"] // => "b" |
| * a['b'] // => "b" |
| * a[`b`] // => "b" |
| * a[100] // => "100" |
| * a[b] // => null |
| * a["a" + "b"] // => null |
| * a[tag`b`] // => null |
| * a[`${b}`] // => null |
| * |
| * let a = {b: 1} // => "b" |
| * let a = {["b"]: 1} // => "b" |
| * let a = {['b']: 1} // => "b" |
| * let a = {[`b`]: 1} // => "b" |
| * let a = {[100]: 1} // => "100" |
| * let a = {[b]: 1} // => null |
| * let a = {["a" + "b"]: 1} // => null |
| * let a = {[tag`b`]: 1} // => null |
| * let a = {[`${b}`]: 1} // => null |
| * |
| * @param {ASTNode} node - The node to get. |
| * @returns {string|null} The property name if static. Otherwise, null. |
| */ |
| getStaticPropertyName(node) { |
| let prop; |
| |
| switch (node && node.type) { |
| case "Property": |
| case "MethodDefinition": |
| prop = node.key; |
| break; |
| |
| case "MemberExpression": |
| prop = node.property; |
| break; |
| |
| // no default |
| } |
| |
| switch (prop && prop.type) { |
| case "Literal": |
| return String(prop.value); |
| |
| case "TemplateLiteral": |
| if (prop.expressions.length === 0 && prop.quasis.length === 1) { |
| return prop.quasis[0].value.cooked; |
| } |
| break; |
| |
| case "Identifier": |
| if (!node.computed) { |
| return prop.name; |
| } |
| break; |
| |
| // no default |
| } |
| |
| return null; |
| }, |
| |
| /** |
| * Get directives from directive prologue of a Program or Function node. |
| * @param {ASTNode} node - The node to check. |
| * @returns {ASTNode[]} The directives found in the directive prologue. |
| */ |
| getDirectivePrologue(node) { |
| const directives = []; |
| |
| // Directive prologues only occur at the top of files or functions. |
| if ( |
| node.type === "Program" || |
| node.type === "FunctionDeclaration" || |
| node.type === "FunctionExpression" || |
| |
| /* |
| * Do not check arrow functions with implicit return. |
| * `() => "use strict";` returns the string `"use strict"`. |
| */ |
| (node.type === "ArrowFunctionExpression" && node.body.type === "BlockStatement") |
| ) { |
| const statements = node.type === "Program" ? node.body : node.body.body; |
| |
| for (const statement of statements) { |
| if ( |
| statement.type === "ExpressionStatement" && |
| statement.expression.type === "Literal" |
| ) { |
| directives.push(statement); |
| } else { |
| break; |
| } |
| } |
| } |
| |
| return directives; |
| }, |
| |
| |
| /** |
| * Determines whether this node is a decimal integer literal. If a node is a decimal integer literal, a dot added |
| * after the node will be parsed as a decimal point, rather than a property-access dot. |
| * @param {ASTNode} node - The node to check. |
| * @returns {boolean} `true` if this node is a decimal integer. |
| * @example |
| * |
| * 5 // true |
| * 5. // false |
| * 5.0 // false |
| * 05 // false |
| * 0x5 // false |
| * 0b101 // false |
| * 0o5 // false |
| * 5e0 // false |
| * '5' // false |
| */ |
| isDecimalInteger(node) { |
| return node.type === "Literal" && typeof node.value === "number" && /^(0|[1-9]\d*)$/u.test(node.raw); |
| }, |
| |
| /** |
| * Gets the name and kind of the given function node. |
| * |
| * - `function foo() {}` .................... `function 'foo'` |
| * - `(function foo() {})` .................. `function 'foo'` |
| * - `(function() {})` ...................... `function` |
| * - `function* foo() {}` ................... `generator function 'foo'` |
| * - `(function* foo() {})` ................. `generator function 'foo'` |
| * - `(function*() {})` ..................... `generator function` |
| * - `() => {}` ............................. `arrow function` |
| * - `async () => {}` ....................... `async arrow function` |
| * - `({ foo: function foo() {} })` ......... `method 'foo'` |
| * - `({ foo: function() {} })` ............. `method 'foo'` |
| * - `({ ['foo']: function() {} })` ......... `method 'foo'` |
| * - `({ [foo]: function() {} })` ........... `method` |
| * - `({ foo() {} })` ....................... `method 'foo'` |
| * - `({ foo: function* foo() {} })` ........ `generator method 'foo'` |
| * - `({ foo: function*() {} })` ............ `generator method 'foo'` |
| * - `({ ['foo']: function*() {} })` ........ `generator method 'foo'` |
| * - `({ [foo]: function*() {} })` .......... `generator method` |
| * - `({ *foo() {} })` ...................... `generator method 'foo'` |
| * - `({ foo: async function foo() {} })` ... `async method 'foo'` |
| * - `({ foo: async function() {} })` ....... `async method 'foo'` |
| * - `({ ['foo']: async function() {} })` ... `async method 'foo'` |
| * - `({ [foo]: async function() {} })` ..... `async method` |
| * - `({ async foo() {} })` ................. `async method 'foo'` |
| * - `({ get foo() {} })` ................... `getter 'foo'` |
| * - `({ set foo(a) {} })` .................. `setter 'foo'` |
| * - `class A { constructor() {} }` ......... `constructor` |
| * - `class A { foo() {} }` ................. `method 'foo'` |
| * - `class A { *foo() {} }` ................ `generator method 'foo'` |
| * - `class A { async foo() {} }` ........... `async method 'foo'` |
| * - `class A { ['foo']() {} }` ............. `method 'foo'` |
| * - `class A { *['foo']() {} }` ............ `generator method 'foo'` |
| * - `class A { async ['foo']() {} }` ....... `async method 'foo'` |
| * - `class A { [foo]() {} }` ............... `method` |
| * - `class A { *[foo]() {} }` .............. `generator method` |
| * - `class A { async [foo]() {} }` ......... `async method` |
| * - `class A { get foo() {} }` ............. `getter 'foo'` |
| * - `class A { set foo(a) {} }` ............ `setter 'foo'` |
| * - `class A { static foo() {} }` .......... `static method 'foo'` |
| * - `class A { static *foo() {} }` ......... `static generator method 'foo'` |
| * - `class A { static async foo() {} }` .... `static async method 'foo'` |
| * - `class A { static get foo() {} }` ...... `static getter 'foo'` |
| * - `class A { static set foo(a) {} }` ..... `static setter 'foo'` |
| * |
| * @param {ASTNode} node - The function node to get. |
| * @returns {string} The name and kind of the function node. |
| */ |
| getFunctionNameWithKind(node) { |
| const parent = node.parent; |
| const tokens = []; |
| |
| if (parent.type === "MethodDefinition" && parent.static) { |
| tokens.push("static"); |
| } |
| if (node.async) { |
| tokens.push("async"); |
| } |
| if (node.generator) { |
| tokens.push("generator"); |
| } |
| |
| if (node.type === "ArrowFunctionExpression") { |
| tokens.push("arrow", "function"); |
| } else if (parent.type === "Property" || parent.type === "MethodDefinition") { |
| if (parent.kind === "constructor") { |
| return "constructor"; |
| } |
| if (parent.kind === "get") { |
| tokens.push("getter"); |
| } else if (parent.kind === "set") { |
| tokens.push("setter"); |
| } else { |
| tokens.push("method"); |
| } |
| } else { |
| tokens.push("function"); |
| } |
| |
| if (node.id) { |
| tokens.push(`'${node.id.name}'`); |
| } else { |
| const name = module.exports.getStaticPropertyName(parent); |
| |
| if (name) { |
| tokens.push(`'${name}'`); |
| } |
| } |
| |
| return tokens.join(" "); |
| }, |
| |
| /** |
| * Gets the location of the given function node for reporting. |
| * |
| * - `function foo() {}` |
| * ^^^^^^^^^^^^ |
| * - `(function foo() {})` |
| * ^^^^^^^^^^^^ |
| * - `(function() {})` |
| * ^^^^^^^^ |
| * - `function* foo() {}` |
| * ^^^^^^^^^^^^^ |
| * - `(function* foo() {})` |
| * ^^^^^^^^^^^^^ |
| * - `(function*() {})` |
| * ^^^^^^^^^ |
| * - `() => {}` |
| * ^^ |
| * - `async () => {}` |
| * ^^ |
| * - `({ foo: function foo() {} })` |
| * ^^^^^^^^^^^^^^^^^ |
| * - `({ foo: function() {} })` |
| * ^^^^^^^^^^^^^ |
| * - `({ ['foo']: function() {} })` |
| * ^^^^^^^^^^^^^^^^^ |
| * - `({ [foo]: function() {} })` |
| * ^^^^^^^^^^^^^^^ |
| * - `({ foo() {} })` |
| * ^^^ |
| * - `({ foo: function* foo() {} })` |
| * ^^^^^^^^^^^^^^^^^^ |
| * - `({ foo: function*() {} })` |
| * ^^^^^^^^^^^^^^ |
| * - `({ ['foo']: function*() {} })` |
| * ^^^^^^^^^^^^^^^^^^ |
| * - `({ [foo]: function*() {} })` |
| * ^^^^^^^^^^^^^^^^ |
| * - `({ *foo() {} })` |
| * ^^^^ |
| * - `({ foo: async function foo() {} })` |
| * ^^^^^^^^^^^^^^^^^^^^^^^ |
| * - `({ foo: async function() {} })` |
| * ^^^^^^^^^^^^^^^^^^^ |
| * - `({ ['foo']: async function() {} })` |
| * ^^^^^^^^^^^^^^^^^^^^^^^ |
| * - `({ [foo]: async function() {} })` |
| * ^^^^^^^^^^^^^^^^^^^^^ |
| * - `({ async foo() {} })` |
| * ^^^^^^^^^ |
| * - `({ get foo() {} })` |
| * ^^^^^^^ |
| * - `({ set foo(a) {} })` |
| * ^^^^^^^ |
| * - `class A { constructor() {} }` |
| * ^^^^^^^^^^^ |
| * - `class A { foo() {} }` |
| * ^^^ |
| * - `class A { *foo() {} }` |
| * ^^^^ |
| * - `class A { async foo() {} }` |
| * ^^^^^^^^^ |
| * - `class A { ['foo']() {} }` |
| * ^^^^^^^ |
| * - `class A { *['foo']() {} }` |
| * ^^^^^^^^ |
| * - `class A { async ['foo']() {} }` |
| * ^^^^^^^^^^^^^ |
| * - `class A { [foo]() {} }` |
| * ^^^^^ |
| * - `class A { *[foo]() {} }` |
| * ^^^^^^ |
| * - `class A { async [foo]() {} }` |
| * ^^^^^^^^^^^ |
| * - `class A { get foo() {} }` |
| * ^^^^^^^ |
| * - `class A { set foo(a) {} }` |
| * ^^^^^^^ |
| * - `class A { static foo() {} }` |
| * ^^^^^^^^^^ |
| * - `class A { static *foo() {} }` |
| * ^^^^^^^^^^^ |
| * - `class A { static async foo() {} }` |
| * ^^^^^^^^^^^^^^^^ |
| * - `class A { static get foo() {} }` |
| * ^^^^^^^^^^^^^^ |
| * - `class A { static set foo(a) {} }` |
| * ^^^^^^^^^^^^^^ |
| * |
| * @param {ASTNode} node - The function node to get. |
| * @param {SourceCode} sourceCode - The source code object to get tokens. |
| * @returns {string} The location of the function node for reporting. |
| */ |
| getFunctionHeadLoc(node, sourceCode) { |
| const parent = node.parent; |
| let start = null; |
| let end = null; |
| |
| if (node.type === "ArrowFunctionExpression") { |
| const arrowToken = sourceCode.getTokenBefore(node.body, isArrowToken); |
| |
| start = arrowToken.loc.start; |
| end = arrowToken.loc.end; |
| } else if (parent.type === "Property" || parent.type === "MethodDefinition") { |
| start = parent.loc.start; |
| end = getOpeningParenOfParams(node, sourceCode).loc.start; |
| } else { |
| start = node.loc.start; |
| end = getOpeningParenOfParams(node, sourceCode).loc.start; |
| } |
| |
| return { |
| start: Object.assign({}, start), |
| end: Object.assign({}, end) |
| }; |
| }, |
| |
| /** |
| * Gets the parenthesized text of a node. This is similar to sourceCode.getText(node), but it also includes any parentheses |
| * surrounding the node. |
| * @param {SourceCode} sourceCode The source code object |
| * @param {ASTNode} node An expression node |
| * @returns {string} The text representing the node, with all surrounding parentheses included |
| */ |
| getParenthesisedText(sourceCode, node) { |
| let leftToken = sourceCode.getFirstToken(node); |
| let rightToken = sourceCode.getLastToken(node); |
| |
| while ( |
| sourceCode.getTokenBefore(leftToken) && |
| sourceCode.getTokenBefore(leftToken).type === "Punctuator" && |
| sourceCode.getTokenBefore(leftToken).value === "(" && |
| sourceCode.getTokenAfter(rightToken) && |
| sourceCode.getTokenAfter(rightToken).type === "Punctuator" && |
| sourceCode.getTokenAfter(rightToken).value === ")" |
| ) { |
| leftToken = sourceCode.getTokenBefore(leftToken); |
| rightToken = sourceCode.getTokenAfter(rightToken); |
| } |
| |
| return sourceCode.getText().slice(leftToken.range[0], rightToken.range[1]); |
| }, |
| |
| /* |
| * Determine if a node has a possiblity to be an Error object |
| * @param {ASTNode} node ASTNode to check |
| * @returns {boolean} True if there is a chance it contains an Error obj |
| */ |
| couldBeError(node) { |
| switch (node.type) { |
| case "Identifier": |
| case "CallExpression": |
| case "NewExpression": |
| case "MemberExpression": |
| case "TaggedTemplateExpression": |
| case "YieldExpression": |
| case "AwaitExpression": |
| return true; // possibly an error object. |
| |
| case "AssignmentExpression": |
| return module.exports.couldBeError(node.right); |
| |
| case "SequenceExpression": { |
| const exprs = node.expressions; |
| |
| return exprs.length !== 0 && module.exports.couldBeError(exprs[exprs.length - 1]); |
| } |
| |
| case "LogicalExpression": |
| return module.exports.couldBeError(node.left) || module.exports.couldBeError(node.right); |
| |
| case "ConditionalExpression": |
| return module.exports.couldBeError(node.consequent) || module.exports.couldBeError(node.alternate); |
| |
| default: |
| return false; |
| } |
| }, |
| |
| /** |
| * Determines whether the given node is a `null` literal. |
| * @param {ASTNode} node The node to check |
| * @returns {boolean} `true` if the node is a `null` literal |
| */ |
| isNullLiteral(node) { |
| |
| /* |
| * Checking `node.value === null` does not guarantee that a literal is a null literal. |
| * When parsing values that cannot be represented in the current environment (e.g. unicode |
| * regexes in Node 4), `node.value` is set to `null` because it wouldn't be possible to |
| * set `node.value` to a unicode regex. To make sure a literal is actually `null`, check |
| * `node.regex` instead. Also see: https://github.com/eslint/eslint/issues/8020 |
| */ |
| return node.type === "Literal" && node.value === null && !node.regex; |
| }, |
| |
| /** |
| * Determines whether two tokens can safely be placed next to each other without merging into a single token |
| * @param {Token|string} leftValue The left token. If this is a string, it will be tokenized and the last token will be used. |
| * @param {Token|string} rightValue The right token. If this is a string, it will be tokenized and the first token will be used. |
| * @returns {boolean} If the tokens cannot be safely placed next to each other, returns `false`. If the tokens can be placed |
| * next to each other, behavior is undefined (although it should return `true` in most cases). |
| */ |
| canTokensBeAdjacent(leftValue, rightValue) { |
| let leftToken; |
| |
| if (typeof leftValue === "string") { |
| const leftTokens = espree.tokenize(leftValue, { ecmaVersion: 2015 }); |
| |
| leftToken = leftTokens[leftTokens.length - 1]; |
| } else { |
| leftToken = leftValue; |
| } |
| |
| const rightToken = typeof rightValue === "string" ? espree.tokenize(rightValue, { ecmaVersion: 2015 })[0] : rightValue; |
| |
| if (leftToken.type === "Punctuator" || rightToken.type === "Punctuator") { |
| if (leftToken.type === "Punctuator" && rightToken.type === "Punctuator") { |
| const PLUS_TOKENS = new Set(["+", "++"]); |
| const MINUS_TOKENS = new Set(["-", "--"]); |
| |
| return !( |
| PLUS_TOKENS.has(leftToken.value) && PLUS_TOKENS.has(rightToken.value) || |
| MINUS_TOKENS.has(leftToken.value) && MINUS_TOKENS.has(rightToken.value) |
| ); |
| } |
| return true; |
| } |
| |
| if ( |
| leftToken.type === "String" || rightToken.type === "String" || |
| leftToken.type === "Template" || rightToken.type === "Template" |
| ) { |
| return true; |
| } |
| |
| if (leftToken.type !== "Numeric" && rightToken.type === "Numeric" && rightToken.value.startsWith(".")) { |
| return true; |
| } |
| |
| return false; |
| }, |
| |
| /** |
| * Get the `loc` object of a given name in a `/*globals` directive comment. |
| * @param {SourceCode} sourceCode The source code to convert index to loc. |
| * @param {Comment} comment The `/*globals` directive comment which include the name. |
| * @param {string} name The name to find. |
| * @returns {SourceLocation} The `loc` object. |
| */ |
| getNameLocationInGlobalDirectiveComment(sourceCode, comment, name) { |
| const namePattern = new RegExp(`[\\s,]${lodash.escapeRegExp(name)}(?:$|[\\s,:])`, "gu"); |
| |
| // To ignore the first text "global". |
| namePattern.lastIndex = comment.value.indexOf("global") + 6; |
| |
| // Search a given variable name. |
| const match = namePattern.exec(comment.value); |
| |
| // Convert the index to loc. |
| return sourceCode.getLocFromIndex( |
| comment.range[0] + |
| "/*".length + |
| (match ? match.index + 1 : 0) |
| ); |
| } |
| }; |
