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							- /**
 
-  * @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"]);
 
- const DECIMAL_INTEGER_PATTERN = /^(?:0|0[0-7]*[89]\d*|[1-9](?:_?\d)*)$/u;
 
- // Tests the presence of at least one LegacyOctalEscapeSequence or NonOctalDecimalEscapeSequence in a raw string
 
- const OCTAL_OR_NON_OCTAL_DECIMAL_ESCAPE_PATTERN = /^(?:[^\\]|\\.)*\\(?:[1-9]|0[0-9])/su;
 
- const LOGICAL_ASSIGNMENT_OPERATORS = new Set(["&&=", "||=", "??="]);
 
- /**
 
-  * 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;
 
- }
 
- /**
 
-  * 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
 
-  */
 
- function 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 && !node.bigint;
 
- }
 
- /**
 
-  * 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 (
 
-         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;
 
- }
 
- /**
 
-  * Returns the result of the string conversion applied to the evaluated value of the given expression node,
 
-  * if it can be determined statically.
 
-  *
 
-  * This function returns a `string` value for all `Literal` nodes and simple `TemplateLiteral` nodes only.
 
-  * In all other cases, this function returns `null`.
 
-  * @param {ASTNode} node Expression node.
 
-  * @returns {string|null} String value if it can be determined. Otherwise, `null`.
 
-  */
 
- function getStaticStringValue(node) {
 
-     switch (node.type) {
 
-         case "Literal":
 
-             if (node.value === null) {
 
-                 if (isNullLiteral(node)) {
 
-                     return String(node.value); // "null"
 
-                 }
 
-                 if (node.regex) {
 
-                     return `/${node.regex.pattern}/${node.regex.flags}`;
 
-                 }
 
-                 if (node.bigint) {
 
-                     return node.bigint;
 
-                 }
 
-                 // Otherwise, this is an unknown literal. The function will return null.
 
-             } else {
 
-                 return String(node.value);
 
-             }
 
-             break;
 
-         case "TemplateLiteral":
 
-             if (node.expressions.length === 0 && node.quasis.length === 1) {
 
-                 return node.quasis[0].value.cooked;
 
-             }
 
-             break;
 
-             // no default
 
-     }
 
-     return null;
 
- }
 
- /**
 
-  * 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.
 
-  */
 
- function getStaticPropertyName(node) {
 
-     let prop;
 
-     switch (node && node.type) {
 
-         case "ChainExpression":
 
-             return getStaticPropertyName(node.expression);
 
-         case "Property":
 
-         case "MethodDefinition":
 
-             prop = node.key;
 
-             break;
 
-         case "MemberExpression":
 
-             prop = node.property;
 
-             break;
 
-             // no default
 
-     }
 
-     if (prop) {
 
-         if (prop.type === "Identifier" && !node.computed) {
 
-             return prop.name;
 
-         }
 
-         return getStaticStringValue(prop);
 
-     }
 
-     return null;
 
- }
 
- /**
 
-  * Retrieve `ChainExpression#expression` value if the given node a `ChainExpression` node. Otherwise, pass through it.
 
-  * @param {ASTNode} node The node to address.
 
-  * @returns {ASTNode} The `ChainExpression#expression` value if the node is a `ChainExpression` node. Otherwise, the node.
 
-  */
 
- function skipChainExpression(node) {
 
-     return node && node.type === "ChainExpression" ? node.expression : node;
 
- }
 
- /**
 
-  * Check if the `actual` is an expected value.
 
-  * @param {string} actual The string value to check.
 
-  * @param {string | RegExp} expected The expected string value or pattern.
 
-  * @returns {boolean} `true` if the `actual` is an expected value.
 
-  */
 
- function checkText(actual, expected) {
 
-     return typeof expected === "string"
 
-         ? actual === expected
 
-         : expected.test(actual);
 
- }
 
- /**
 
-  * Check if a given node is an Identifier node with a given name.
 
-  * @param {ASTNode} node The node to check.
 
-  * @param {string | RegExp} name The expected name or the expected pattern of the object name.
 
-  * @returns {boolean} `true` if the node is an Identifier node with the name.
 
-  */
 
- function isSpecificId(node, name) {
 
-     return node.type === "Identifier" && checkText(node.name, name);
 
- }
 
- /**
 
-  * Check if a given node is member access with a given object name and property name pair.
 
-  * This is regardless of optional or not.
 
-  * @param {ASTNode} node The node to check.
 
-  * @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.
 
-  * @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.
 
-  * @returns {boolean} `true` if the node is member access with the object name and property name pair.
 
-  * The node is a `MemberExpression` or `ChainExpression`.
 
-  */
 
- function isSpecificMemberAccess(node, objectName, propertyName) {
 
-     const checkNode = skipChainExpression(node);
 
-     if (checkNode.type !== "MemberExpression") {
 
-         return false;
 
-     }
 
-     if (objectName && !isSpecificId(checkNode.object, objectName)) {
 
-         return false;
 
-     }
 
-     if (propertyName) {
 
-         const actualPropertyName = getStaticPropertyName(checkNode);
 
-         if (typeof actualPropertyName !== "string" || !checkText(actualPropertyName, propertyName)) {
 
-             return false;
 
-         }
 
-     }
 
-     return true;
 
- }
 
- /**
 
-  * Check if two literal nodes are the same value.
 
-  * @param {ASTNode} left The Literal node to compare.
 
-  * @param {ASTNode} right The other Literal node to compare.
 
-  * @returns {boolean} `true` if the two literal nodes are the same value.
 
-  */
 
- function equalLiteralValue(left, right) {
 
-     // RegExp literal.
 
-     if (left.regex || right.regex) {
 
-         return Boolean(
 
-             left.regex &&
 
-             right.regex &&
 
-             left.regex.pattern === right.regex.pattern &&
 
-             left.regex.flags === right.regex.flags
 
-         );
 
-     }
 
-     // BigInt literal.
 
-     if (left.bigint || right.bigint) {
 
-         return left.bigint === right.bigint;
 
-     }
 
-     return left.value === right.value;
 
- }
 
- /**
 
-  * Check if two expressions reference the same value. For example:
 
-  *     a = a
 
-  *     a.b = a.b
 
-  *     a[0] = a[0]
 
-  *     a['b'] = a['b']
 
-  * @param {ASTNode} left The left side of the comparison.
 
-  * @param {ASTNode} right The right side of the comparison.
 
-  * @param {boolean} [disableStaticComputedKey] Don't address `a.b` and `a["b"]` are the same if `true`. For backward compatibility.
 
-  * @returns {boolean} `true` if both sides match and reference the same value.
 
-  */
 
- function isSameReference(left, right, disableStaticComputedKey = false) {
 
-     if (left.type !== right.type) {
 
-         // Handle `a.b` and `a?.b` are samely.
 
-         if (left.type === "ChainExpression") {
 
-             return isSameReference(left.expression, right, disableStaticComputedKey);
 
-         }
 
-         if (right.type === "ChainExpression") {
 
-             return isSameReference(left, right.expression, disableStaticComputedKey);
 
-         }
 
-         return false;
 
-     }
 
-     switch (left.type) {
 
-         case "Super":
 
-         case "ThisExpression":
 
-             return true;
 
-         case "Identifier":
 
-             return left.name === right.name;
 
-         case "Literal":
 
-             return equalLiteralValue(left, right);
 
-         case "ChainExpression":
 
-             return isSameReference(left.expression, right.expression, disableStaticComputedKey);
 
-         case "MemberExpression": {
 
-             if (!disableStaticComputedKey) {
 
-                 const nameA = getStaticPropertyName(left);
 
-                 // x.y = x["y"]
 
-                 if (nameA !== null) {
 
-                     return (
 
-                         isSameReference(left.object, right.object, disableStaticComputedKey) &&
 
-                         nameA === getStaticPropertyName(right)
 
-                     );
 
-                 }
 
-             }
 
-             /*
 
-              * x[0] = x[0]
 
-              * x[y] = x[y]
 
-              * x.y = x.y
 
-              */
 
-             return (
 
-                 left.computed === right.computed &&
 
-                 isSameReference(left.object, right.object, disableStaticComputedKey) &&
 
-                 isSameReference(left.property, right.property, disableStaticComputedKey)
 
-             );
 
-         }
 
-         default:
 
-             return false;
 
-     }
 
- }
 
- /**
 
-  * 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 isSpecificMemberAccess(node, "Reflect", "apply");
 
- }
 
- /**
 
-  * 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 isSpecificMemberAccess(node, arrayOrTypedArrayPattern, "from");
 
- }
 
- /**
 
-  * 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) {
 
-     return isSpecificMemberAccess(node, null, arrayMethodPattern);
 
- }
 
- /**
 
-  * 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 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 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":
 
-             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,]${lodash.escapeRegExp(name)}(?:$|[\\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.
 
-         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
 
- };
 
 
  |