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1809 lines
61 KiB
1809 lines
61 KiB
/** |
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* @fileoverview Common utils for AST. |
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* @author Gyandeep Singh |
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*/ |
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|
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"use strict"; |
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|
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//------------------------------------------------------------------------------ |
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// Requirements |
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//------------------------------------------------------------------------------ |
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|
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const esutils = require("esutils"); |
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const espree = require("espree"); |
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const escapeRegExp = require("escape-string-regexp"); |
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const { |
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breakableTypePattern, |
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createGlobalLinebreakMatcher, |
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lineBreakPattern, |
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shebangPattern |
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} = require("../../shared/ast-utils"); |
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//------------------------------------------------------------------------------ |
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// Helpers |
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//------------------------------------------------------------------------------ |
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const anyFunctionPattern = /^(?:Function(?:Declaration|Expression)|ArrowFunctionExpression)$/u; |
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const anyLoopPattern = /^(?:DoWhile|For|ForIn|ForOf|While)Statement$/u; |
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const arrayOrTypedArrayPattern = /Array$/u; |
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const arrayMethodPattern = /^(?:every|filter|find|findIndex|forEach|map|some)$/u; |
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const bindOrCallOrApplyPattern = /^(?:bind|call|apply)$/u; |
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const thisTagPattern = /^[\s*]*@this/mu; |
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const COMMENTS_IGNORE_PATTERN = /^\s*(?:eslint|jshint\s+|jslint\s+|istanbul\s+|globals?\s+|exported\s+|jscs)/u; |
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const LINEBREAKS = new Set(["\r\n", "\r", "\n", "\u2028", "\u2029"]); |
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// A set of node types that can contain a list of statements |
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const STATEMENT_LIST_PARENTS = new Set(["Program", "BlockStatement", "SwitchCase"]); |
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const DECIMAL_INTEGER_PATTERN = /^(?:0|0[0-7]*[89]\d*|[1-9](?:_?\d)*)$/u; |
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// Tests the presence of at least one LegacyOctalEscapeSequence or NonOctalDecimalEscapeSequence in a raw string |
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const OCTAL_OR_NON_OCTAL_DECIMAL_ESCAPE_PATTERN = /^(?:[^\\]|\\.)*\\(?:[1-9]|0[0-9])/su; |
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const LOGICAL_ASSIGNMENT_OPERATORS = new Set(["&&=", "||=", "??="]); |
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/** |
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* Checks reference if is non initializer and writable. |
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* @param {Reference} reference A reference to check. |
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* @param {int} index The index of the reference in the references. |
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* @param {Reference[]} references The array that the reference belongs to. |
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* @returns {boolean} Success/Failure |
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* @private |
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*/ |
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function isModifyingReference(reference, index, references) { |
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const identifier = reference.identifier; |
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/* |
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* Destructuring assignments can have multiple default value, so |
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* possibly there are multiple writeable references for the same |
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* identifier. |
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*/ |
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const modifyingDifferentIdentifier = index === 0 || |
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references[index - 1].identifier !== identifier; |
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return (identifier && |
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reference.init === false && |
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reference.isWrite() && |
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modifyingDifferentIdentifier |
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); |
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} |
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/** |
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* Checks whether the given string starts with uppercase or not. |
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* @param {string} s The string to check. |
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* @returns {boolean} `true` if the string starts with uppercase. |
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*/ |
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function startsWithUpperCase(s) { |
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return s[0] !== s[0].toLocaleLowerCase(); |
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} |
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/** |
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* Checks whether or not a node is a constructor. |
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* @param {ASTNode} node A function node to check. |
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* @returns {boolean} Whether or not a node is a constructor. |
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*/ |
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function isES5Constructor(node) { |
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return (node.id && startsWithUpperCase(node.id.name)); |
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} |
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/** |
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* Finds a function node from ancestors of a node. |
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* @param {ASTNode} node A start node to find. |
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* @returns {Node|null} A found function node. |
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*/ |
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function getUpperFunction(node) { |
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for (let currentNode = node; currentNode; currentNode = currentNode.parent) { |
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if (anyFunctionPattern.test(currentNode.type)) { |
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return currentNode; |
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} |
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} |
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return null; |
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} |
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/** |
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* Checks whether a given node is a function node or not. |
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* The following types are function nodes: |
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* |
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* - ArrowFunctionExpression |
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* - FunctionDeclaration |
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* - FunctionExpression |
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* @param {ASTNode|null} node A node to check. |
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* @returns {boolean} `true` if the node is a function node. |
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*/ |
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function isFunction(node) { |
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return Boolean(node && anyFunctionPattern.test(node.type)); |
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} |
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/** |
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* Checks whether a given node is a loop node or not. |
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* The following types are loop nodes: |
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* |
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* - DoWhileStatement |
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* - ForInStatement |
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* - ForOfStatement |
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* - ForStatement |
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* - WhileStatement |
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* @param {ASTNode|null} node A node to check. |
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* @returns {boolean} `true` if the node is a loop node. |
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*/ |
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function isLoop(node) { |
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return Boolean(node && anyLoopPattern.test(node.type)); |
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} |
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/** |
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* Checks whether the given node is in a loop or not. |
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* @param {ASTNode} node The node to check. |
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* @returns {boolean} `true` if the node is in a loop. |
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*/ |
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function isInLoop(node) { |
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for (let currentNode = node; currentNode && !isFunction(currentNode); currentNode = currentNode.parent) { |
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if (isLoop(currentNode)) { |
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return true; |
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} |
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} |
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return false; |
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} |
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/** |
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* Determines whether the given node is a `null` literal. |
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* @param {ASTNode} node The node to check |
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* @returns {boolean} `true` if the node is a `null` literal |
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*/ |
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function isNullLiteral(node) { |
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/* |
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* Checking `node.value === null` does not guarantee that a literal is a null literal. |
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* When parsing values that cannot be represented in the current environment (e.g. unicode |
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* regexes in Node 4), `node.value` is set to `null` because it wouldn't be possible to |
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* set `node.value` to a unicode regex. To make sure a literal is actually `null`, check |
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* `node.regex` instead. Also see: https://github.com/eslint/eslint/issues/8020 |
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*/ |
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return node.type === "Literal" && node.value === null && !node.regex && !node.bigint; |
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} |
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/** |
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* Checks whether or not a node is `null` or `undefined`. |
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* @param {ASTNode} node A node to check. |
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* @returns {boolean} Whether or not the node is a `null` or `undefined`. |
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* @public |
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*/ |
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function isNullOrUndefined(node) { |
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return ( |
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isNullLiteral(node) || |
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(node.type === "Identifier" && node.name === "undefined") || |
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(node.type === "UnaryExpression" && node.operator === "void") |
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); |
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} |
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/** |
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* Checks whether or not a node is callee. |
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* @param {ASTNode} node A node to check. |
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* @returns {boolean} Whether or not the node is callee. |
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*/ |
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function isCallee(node) { |
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return node.parent.type === "CallExpression" && node.parent.callee === node; |
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} |
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/** |
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* Returns the result of the string conversion applied to the evaluated value of the given expression node, |
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* if it can be determined statically. |
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* |
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* This function returns a `string` value for all `Literal` nodes and simple `TemplateLiteral` nodes only. |
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* In all other cases, this function returns `null`. |
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* @param {ASTNode} node Expression node. |
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* @returns {string|null} String value if it can be determined. Otherwise, `null`. |
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*/ |
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function getStaticStringValue(node) { |
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switch (node.type) { |
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case "Literal": |
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if (node.value === null) { |
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if (isNullLiteral(node)) { |
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return String(node.value); // "null" |
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} |
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if (node.regex) { |
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return `/${node.regex.pattern}/${node.regex.flags}`; |
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} |
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if (node.bigint) { |
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return node.bigint; |
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} |
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// Otherwise, this is an unknown literal. The function will return null. |
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} else { |
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return String(node.value); |
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} |
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break; |
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case "TemplateLiteral": |
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if (node.expressions.length === 0 && node.quasis.length === 1) { |
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return node.quasis[0].value.cooked; |
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} |
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break; |
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// no default |
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} |
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return null; |
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} |
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/** |
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* Gets the property name of a given node. |
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* The node can be a MemberExpression, a Property, or a MethodDefinition. |
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* |
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* If the name is dynamic, this returns `null`. |
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* |
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* For examples: |
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* |
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* a.b // => "b" |
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* a["b"] // => "b" |
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* a['b'] // => "b" |
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* a[`b`] // => "b" |
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* a[100] // => "100" |
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* a[b] // => null |
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* a["a" + "b"] // => null |
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* a[tag`b`] // => null |
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* a[`${b}`] // => null |
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* |
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* let a = {b: 1} // => "b" |
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* let a = {["b"]: 1} // => "b" |
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* let a = {['b']: 1} // => "b" |
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* let a = {[`b`]: 1} // => "b" |
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* let a = {[100]: 1} // => "100" |
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* let a = {[b]: 1} // => null |
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* let a = {["a" + "b"]: 1} // => null |
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* let a = {[tag`b`]: 1} // => null |
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* let a = {[`${b}`]: 1} // => null |
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* @param {ASTNode} node The node to get. |
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* @returns {string|null} The property name if static. Otherwise, null. |
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*/ |
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function getStaticPropertyName(node) { |
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let prop; |
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switch (node && node.type) { |
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case "ChainExpression": |
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return getStaticPropertyName(node.expression); |
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case "Property": |
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case "MethodDefinition": |
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prop = node.key; |
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break; |
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case "MemberExpression": |
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prop = node.property; |
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break; |
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// no default |
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} |
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if (prop) { |
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if (prop.type === "Identifier" && !node.computed) { |
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return prop.name; |
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} |
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return getStaticStringValue(prop); |
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} |
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return null; |
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} |
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/** |
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* Retrieve `ChainExpression#expression` value if the given node a `ChainExpression` node. Otherwise, pass through it. |
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* @param {ASTNode} node The node to address. |
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* @returns {ASTNode} The `ChainExpression#expression` value if the node is a `ChainExpression` node. Otherwise, the node. |
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*/ |
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function skipChainExpression(node) { |
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return node && node.type === "ChainExpression" ? node.expression : node; |
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} |
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/** |
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* Check if the `actual` is an expected value. |
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* @param {string} actual The string value to check. |
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* @param {string | RegExp} expected The expected string value or pattern. |
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* @returns {boolean} `true` if the `actual` is an expected value. |
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*/ |
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function checkText(actual, expected) { |
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return typeof expected === "string" |
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? actual === expected |
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: expected.test(actual); |
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} |
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/** |
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* Check if a given node is an Identifier node with a given name. |
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* @param {ASTNode} node The node to check. |
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* @param {string | RegExp} name The expected name or the expected pattern of the object name. |
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* @returns {boolean} `true` if the node is an Identifier node with the name. |
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*/ |
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function isSpecificId(node, name) { |
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return node.type === "Identifier" && checkText(node.name, name); |
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} |
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/** |
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* Check if a given node is member access with a given object name and property name pair. |
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* This is regardless of optional or not. |
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* @param {ASTNode} node The node to check. |
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* @param {string | RegExp | null} objectName The expected name or the expected pattern of the object name. If this is nullish, this method doesn't check object. |
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* @param {string | RegExp | null} propertyName The expected name or the expected pattern of the property name. If this is nullish, this method doesn't check property. |
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* @returns {boolean} `true` if the node is member access with the object name and property name pair. |
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* The node is a `MemberExpression` or `ChainExpression`. |
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*/ |
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function isSpecificMemberAccess(node, objectName, propertyName) { |
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const checkNode = skipChainExpression(node); |
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if (checkNode.type !== "MemberExpression") { |
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return false; |
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} |
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if (objectName && !isSpecificId(checkNode.object, objectName)) { |
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return false; |
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} |
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if (propertyName) { |
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const actualPropertyName = getStaticPropertyName(checkNode); |
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if (typeof actualPropertyName !== "string" || !checkText(actualPropertyName, propertyName)) { |
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return false; |
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} |
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} |
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return true; |
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} |
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/** |
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* Check if two literal nodes are the same value. |
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* @param {ASTNode} left The Literal node to compare. |
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* @param {ASTNode} right The other Literal node to compare. |
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* @returns {boolean} `true` if the two literal nodes are the same value. |
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*/ |
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function equalLiteralValue(left, right) { |
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|
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// RegExp literal. |
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if (left.regex || right.regex) { |
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return Boolean( |
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left.regex && |
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right.regex && |
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left.regex.pattern === right.regex.pattern && |
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left.regex.flags === right.regex.flags |
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); |
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} |
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|
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// BigInt literal. |
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if (left.bigint || right.bigint) { |
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return left.bigint === right.bigint; |
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} |
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|
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return left.value === right.value; |
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} |
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/** |
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* Check if two expressions reference the same value. For example: |
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* a = a |
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* a.b = a.b |
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* a[0] = a[0] |
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* a['b'] = a['b'] |
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* @param {ASTNode} left The left side of the comparison. |
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* @param {ASTNode} right The right side of the comparison. |
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* @param {boolean} [disableStaticComputedKey] Don't address `a.b` and `a["b"]` are the same if `true`. For backward compatibility. |
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* @returns {boolean} `true` if both sides match and reference the same value. |
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*/ |
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function isSameReference(left, right, disableStaticComputedKey = false) { |
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if (left.type !== right.type) { |
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|
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// Handle `a.b` and `a?.b` are samely. |
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if (left.type === "ChainExpression") { |
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return isSameReference(left.expression, right, disableStaticComputedKey); |
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} |
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if (right.type === "ChainExpression") { |
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return isSameReference(left, right.expression, disableStaticComputedKey); |
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} |
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return false; |
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} |
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switch (left.type) { |
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case "Super": |
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case "ThisExpression": |
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return true; |
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|
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case "Identifier": |
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return left.name === right.name; |
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case "Literal": |
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return equalLiteralValue(left, right); |
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|
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case "ChainExpression": |
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return isSameReference(left.expression, right.expression, disableStaticComputedKey); |
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|
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case "MemberExpression": { |
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if (!disableStaticComputedKey) { |
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const nameA = getStaticPropertyName(left); |
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|
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// x.y = x["y"] |
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if (nameA !== null) { |
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return ( |
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isSameReference(left.object, right.object, disableStaticComputedKey) && |
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nameA === getStaticPropertyName(right) |
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); |
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} |
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} |
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|
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/* |
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* x[0] = x[0] |
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* x[y] = x[y] |
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* x.y = x.y |
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*/ |
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return ( |
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left.computed === right.computed && |
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isSameReference(left.object, right.object, disableStaticComputedKey) && |
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isSameReference(left.property, right.property, disableStaticComputedKey) |
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); |
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} |
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default: |
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return false; |
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} |
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} |
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|
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/** |
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* Checks whether or not a node is `Reflect.apply`. |
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* @param {ASTNode} node A node to check. |
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* @returns {boolean} Whether or not the node is a `Reflect.apply`. |
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*/ |
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function isReflectApply(node) { |
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return isSpecificMemberAccess(node, "Reflect", "apply"); |
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} |
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|
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/** |
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* Checks whether or not a node is `Array.from`. |
|
* @param {ASTNode} node A node to check. |
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* @returns {boolean} Whether or not the node is a `Array.from`. |
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*/ |
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function isArrayFromMethod(node) { |
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return isSpecificMemberAccess(node, arrayOrTypedArrayPattern, "from"); |
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} |
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|
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/** |
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* 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`. |
|
*/ |
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function isMethodWhichHasThisArg(node) { |
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return isSpecificMemberAccess(node, null, arrayMethodPattern); |
|
} |
|
|
|
/** |
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* Creates the negate function of the given function. |
|
* @param {Function} f The function to negate. |
|
* @returns {Function} Negated function. |
|
*/ |
|
function negate(f) { |
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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 dot token or not. |
|
* @param {Token} token The token to check. |
|
* @returns {boolean} `true` if the token is a dot token. |
|
*/ |
|
function isDotToken(token) { |
|
return token.value === "." && token.type === "Punctuator"; |
|
} |
|
|
|
/** |
|
* Checks if the given token is a `?.` token or not. |
|
* @param {Token} token The token to check. |
|
* @returns {boolean} `true` if the token is a `?.` token. |
|
*/ |
|
function isQuestionDotToken(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; |
|
} |
|
|
|
/** |
|
* Check if the given node is a true logical expression or not. |
|
* |
|
* The three binary expressions logical-or (`||`), logical-and (`&&`), and |
|
* coalesce (`??`) are known as `ShortCircuitExpression`. |
|
* But ESTree represents those by `LogicalExpression` node. |
|
* |
|
* This function rejects coalesce expressions of `LogicalExpression` node. |
|
* @param {ASTNode} node The node to check. |
|
* @returns {boolean} `true` if the node is `&&` or `||`. |
|
* @see https://tc39.es/ecma262/#prod-ShortCircuitExpression |
|
*/ |
|
function isLogicalExpression(node) { |
|
return ( |
|
node.type === "LogicalExpression" && |
|
(node.operator === "&&" || node.operator === "||") |
|
); |
|
} |
|
|
|
/** |
|
* Check if the given node is a nullish coalescing expression or not. |
|
* |
|
* The three binary expressions logical-or (`||`), logical-and (`&&`), and |
|
* coalesce (`??`) are known as `ShortCircuitExpression`. |
|
* But ESTree represents those by `LogicalExpression` node. |
|
* |
|
* This function finds only coalesce expressions of `LogicalExpression` node. |
|
* @param {ASTNode} node The node to check. |
|
* @returns {boolean} `true` if the node is `??`. |
|
*/ |
|
function isCoalesceExpression(node) { |
|
return node.type === "LogicalExpression" && node.operator === "??"; |
|
} |
|
|
|
/** |
|
* Check if given two nodes are the pair of a logical expression and a coalesce expression. |
|
* @param {ASTNode} left A node to check. |
|
* @param {ASTNode} right Another node to check. |
|
* @returns {boolean} `true` if the two nodes are the pair of a logical expression and a coalesce expression. |
|
*/ |
|
function isMixedLogicalAndCoalesceExpressions(left, right) { |
|
return ( |
|
(isLogicalExpression(left) && isCoalesceExpression(right)) || |
|
(isCoalesceExpression(left) && isLogicalExpression(right)) |
|
); |
|
} |
|
|
|
/** |
|
* Checks if the given operator is a logical assignment operator. |
|
* @param {string} operator The operator to check. |
|
* @returns {boolean} `true` if the operator is a logical assignment operator. |
|
*/ |
|
function isLogicalAssignmentOperator(operator) { |
|
return LOGICAL_ASSIGNMENT_OPERATORS.has(operator); |
|
} |
|
|
|
//------------------------------------------------------------------------------ |
|
// 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, |
|
isDotToken, |
|
isQuestionDotToken, |
|
isKeywordToken, |
|
isNotClosingBraceToken: negate(isClosingBraceToken), |
|
isNotClosingBracketToken: negate(isClosingBracketToken), |
|
isNotClosingParenToken: negate(isClosingParenToken), |
|
isNotColonToken: negate(isColonToken), |
|
isNotCommaToken: negate(isCommaToken), |
|
isNotDotToken: negate(isDotToken), |
|
isNotQuestionDotToken: negate(isQuestionDotToken), |
|
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 convention to capitalize the names |
|
* of constructor functions. This check is not performed if `capIsConstructor` is set to `false`. |
|
* - 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. Applies to anonymous |
|
* functions only, as the name of the variable is considered to be the name of the function in this case. |
|
* This check is not performed if `capIsConstructor` is set to `false`. |
|
* - 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. |
|
* @param {boolean} [capIsConstructor = true] `false` disables the assumption that functions which name starts |
|
* with an uppercase or are assigned to a variable which name starts with an uppercase are constructors. |
|
* @returns {boolean} The function node is the default `this` binding. |
|
*/ |
|
isDefaultThisBinding(node, sourceCode, { capIsConstructor = true } = {}) { |
|
if ( |
|
(capIsConstructor && 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": |
|
case "ChainExpression": |
|
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 ( |
|
capIsConstructor && |
|
isAnonymous && |
|
parent.left.type === "Identifier" && |
|
startsWithUpperCase(parent.left.name) |
|
) { |
|
return false; |
|
} |
|
return true; |
|
|
|
/* |
|
* e.g. |
|
* var Foo = function() { ... }; |
|
*/ |
|
case "VariableDeclarator": |
|
return !( |
|
capIsConstructor && |
|
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": |
|
if ( |
|
parent.object === currentNode && |
|
isSpecificMemberAccess(parent, null, bindOrCallOrApplyPattern) |
|
) { |
|
const maybeCalleeNode = parent.parent.type === "ChainExpression" |
|
? parent.parent |
|
: parent; |
|
|
|
return !( |
|
isCallee(maybeCalleeNode) && |
|
maybeCalleeNode.parent.arguments.length >= 1 && |
|
!isNullOrUndefined(maybeCalleeNode.parent.arguments[0]) |
|
); |
|
} |
|
return true; |
|
|
|
/* |
|
* 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 "||": |
|
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": |
|
case "ChainExpression": |
|
case "ImportExpression": |
|
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); |
|
}, |
|
|
|
/** |
|
* 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 |
|
* |
|
* 0 // true |
|
* 5 // true |
|
* 50 // true |
|
* 5_000 // true |
|
* 1_234_56 // true |
|
* 08 // true |
|
* 0192 // true |
|
* 5. // false |
|
* .5 // false |
|
* 5.0 // false |
|
* 5.00_00 // false |
|
* 05 // false |
|
* 0x5 // false |
|
* 0b101 // false |
|
* 0b11_01 // false |
|
* 0o5 // false |
|
* 5e0 // false |
|
* 5e1_000 // false |
|
* 5n // false |
|
* 1_000n // false |
|
* '5' // false |
|
*/ |
|
isDecimalInteger(node) { |
|
return node.type === "Literal" && typeof node.value === "number" && |
|
DECIMAL_INTEGER_PATTERN.test(node.raw); |
|
}, |
|
|
|
/** |
|
* Determines whether this token is a decimal integer numeric token. |
|
* This is similar to isDecimalInteger(), but for tokens. |
|
* @param {Token} token The token to check. |
|
* @returns {boolean} `true` if this token is a decimal integer. |
|
*/ |
|
isDecimalIntegerNumericToken(token) { |
|
return token.type === "Numeric" && DECIMAL_INTEGER_PATTERN.test(token.value); |
|
}, |
|
|
|
/** |
|
* 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(`'${node.id.name}'`); |
|
} else { |
|
const name = getStaticPropertyName(parent); |
|
|
|
if (name !== null) { |
|
tokens.push(`'${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 next location when the result is not out of bound, otherwise returns null. |
|
* |
|
* Assumptions: |
|
* |
|
* - The given location represents a valid location in the given source code. |
|
* - Columns are 0-based. |
|
* - Lines are 1-based. |
|
* - Column immediately after the last character in a line (not incl. linebreaks) is considered to be a valid location. |
|
* - If the source code ends with a linebreak, `sourceCode.lines` array will have an extra element (empty string) at the end. |
|
* The start (column 0) of that extra line is considered to be a valid location. |
|
* |
|
* Examples of successive locations (line, column): |
|
* |
|
* code: foo |
|
* locations: (1, 0) -> (1, 1) -> (1, 2) -> (1, 3) -> null |
|
* |
|
* code: foo<LF> |
|
* locations: (1, 0) -> (1, 1) -> (1, 2) -> (1, 3) -> (2, 0) -> null |
|
* |
|
* code: foo<CR><LF> |
|
* locations: (1, 0) -> (1, 1) -> (1, 2) -> (1, 3) -> (2, 0) -> null |
|
* |
|
* code: a<LF>b |
|
* locations: (1, 0) -> (1, 1) -> (2, 0) -> (2, 1) -> null |
|
* |
|
* code: a<LF>b<LF> |
|
* locations: (1, 0) -> (1, 1) -> (2, 0) -> (2, 1) -> (3, 0) -> null |
|
* |
|
* code: a<CR><LF>b<CR><LF> |
|
* locations: (1, 0) -> (1, 1) -> (2, 0) -> (2, 1) -> (3, 0) -> null |
|
* |
|
* code: a<LF><LF> |
|
* locations: (1, 0) -> (1, 1) -> (2, 0) -> (3, 0) -> null |
|
* |
|
* code: <LF> |
|
* locations: (1, 0) -> (2, 0) -> null |
|
* |
|
* code: |
|
* locations: (1, 0) -> null |
|
* @param {SourceCode} sourceCode The sourceCode |
|
* @param {{line: number, column: number}} location The location |
|
* @returns {{line: number, column: number} | null} Next location |
|
*/ |
|
getNextLocation(sourceCode, { line, column }) { |
|
if (column < sourceCode.lines[line - 1].length) { |
|
return { |
|
line, |
|
column: column + 1 |
|
}; |
|
} |
|
|
|
if (line < sourceCode.lines.length) { |
|
return { |
|
line: line + 1, |
|
column: 0 |
|
}; |
|
} |
|
|
|
return null; |
|
}, |
|
|
|
/** |
|
* 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 possibility 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": |
|
case "ChainExpression": |
|
return true; // possibly an error object. |
|
|
|
case "AssignmentExpression": |
|
if (["=", "&&="].includes(node.operator)) { |
|
return module.exports.couldBeError(node.right); |
|
} |
|
|
|
if (["||=", "??="].includes(node.operator)) { |
|
return module.exports.couldBeError(node.left) || module.exports.couldBeError(node.right); |
|
} |
|
|
|
/** |
|
* All other assignment operators are mathematical assignment operators (arithmetic or bitwise). |
|
* An assignment expression with a mathematical operator can either evaluate to a primitive value, |
|
* or throw, depending on the operands. Thus, it cannot evaluate to an `Error` object. |
|
*/ |
|
return false; |
|
|
|
case "SequenceExpression": { |
|
const exprs = node.expressions; |
|
|
|
return exprs.length !== 0 && module.exports.couldBeError(exprs[exprs.length - 1]); |
|
} |
|
|
|
case "LogicalExpression": |
|
|
|
/* |
|
* If the && operator short-circuits, the left side was falsy and therefore not an error, and if it |
|
* doesn't short-circuit, it takes the value from the right side, so the right side must always be |
|
* a plausible error. A future improvement could verify that the left side could be truthy by |
|
* excluding falsy literals. |
|
*/ |
|
if (node.operator === "&&") { |
|
return module.exports.couldBeError(node.right); |
|
} |
|
|
|
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; |
|
} |
|
}, |
|
|
|
/** |
|
* Check if a given node is a numeric literal or not. |
|
* @param {ASTNode} node The node to check. |
|
* @returns {boolean} `true` if the node is a number or bigint literal. |
|
*/ |
|
isNumericLiteral(node) { |
|
return ( |
|
node.type === "Literal" && |
|
(typeof node.value === "number" || Boolean(node.bigint)) |
|
); |
|
}, |
|
|
|
/** |
|
* 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) { |
|
const espreeOptions = { |
|
ecmaVersion: espree.latestEcmaVersion, |
|
comment: true, |
|
range: true |
|
}; |
|
|
|
let leftToken; |
|
|
|
if (typeof leftValue === "string") { |
|
let tokens; |
|
|
|
try { |
|
tokens = espree.tokenize(leftValue, espreeOptions); |
|
} catch { |
|
return false; |
|
} |
|
|
|
const comments = tokens.comments; |
|
|
|
leftToken = tokens[tokens.length - 1]; |
|
if (comments.length) { |
|
const lastComment = comments[comments.length - 1]; |
|
|
|
if (lastComment.range[0] > leftToken.range[0]) { |
|
leftToken = lastComment; |
|
} |
|
} |
|
} else { |
|
leftToken = leftValue; |
|
} |
|
|
|
if (leftToken.type === "Shebang") { |
|
return false; |
|
} |
|
|
|
let rightToken; |
|
|
|
if (typeof rightValue === "string") { |
|
let tokens; |
|
|
|
try { |
|
tokens = espree.tokenize(rightValue, espreeOptions); |
|
} catch { |
|
return false; |
|
} |
|
|
|
const comments = tokens.comments; |
|
|
|
rightToken = tokens[0]; |
|
if (comments.length) { |
|
const firstComment = comments[0]; |
|
|
|
if (firstComment.range[0] < rightToken.range[0]) { |
|
rightToken = firstComment; |
|
} |
|
} |
|
} else { |
|
rightToken = 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) |
|
); |
|
} |
|
if (leftToken.type === "Punctuator" && leftToken.value === "/") { |
|
return !["Block", "Line", "RegularExpression"].includes(rightToken.type); |
|
} |
|
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; |
|
} |
|
|
|
if (leftToken.type === "Block" || rightToken.type === "Block" || rightToken.type === "Line") { |
|
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,]${escapeRegExp(name)}(?:$|[\\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. |
|
const start = sourceCode.getLocFromIndex( |
|
comment.range[0] + |
|
"/*".length + |
|
(match ? match.index + 1 : 0) |
|
); |
|
const end = { |
|
line: start.line, |
|
column: start.column + (match ? name.length : 1) |
|
}; |
|
|
|
return { start, end }; |
|
}, |
|
|
|
/** |
|
* Determines whether the given raw string contains an octal escape sequence |
|
* or a non-octal decimal escape sequence ("\8", "\9"). |
|
* |
|
* "\1", "\2" ... "\7", "\8", "\9" |
|
* "\00", "\01" ... "\07", "\08", "\09" |
|
* |
|
* "\0", when not followed by a digit, is not an octal escape sequence. |
|
* @param {string} rawString A string in its raw representation. |
|
* @returns {boolean} `true` if the string contains at least one octal escape sequence |
|
* or at least one non-octal decimal escape sequence. |
|
*/ |
|
hasOctalOrNonOctalDecimalEscapeSequence(rawString) { |
|
return OCTAL_OR_NON_OCTAL_DECIMAL_ESCAPE_PATTERN.test(rawString); |
|
}, |
|
|
|
isLogicalExpression, |
|
isCoalesceExpression, |
|
isMixedLogicalAndCoalesceExpressions, |
|
isNullLiteral, |
|
getStaticStringValue, |
|
getStaticPropertyName, |
|
skipChainExpression, |
|
isSpecificId, |
|
isSpecificMemberAccess, |
|
equalLiteralValue, |
|
isSameReference, |
|
isLogicalAssignmentOperator |
|
};
|
|
|