src/third_party/devtools/node_modules/eslint/lib/source-code/source-code.js - cobalt - Git at Google

 /**
  * @fileoverview Abstraction of JavaScript source code.
  * @author Nicholas C. Zakas
  */
 "use strict";

 //------------------------------------------------------------------------------
 // Requirements
 //------------------------------------------------------------------------------

 const
     { isCommentToken } = require("eslint-utils"),
     TokenStore = require("./token-store"),
     astUtils = require("../shared/ast-utils"),
     Traverser = require("../shared/traverser"),
     lodash = require("lodash");

 //------------------------------------------------------------------------------
 // Private
 //------------------------------------------------------------------------------

 /**
  * Validates that the given AST has the required information.
  * @param {ASTNode} ast The Program node of the AST to check.
  * @throws {Error} If the AST doesn't contain the correct information.
  * @returns {void}
  * @private
  */
 function validate(ast) {
     if (!ast.tokens) {
         throw new Error("AST is missing the tokens array.");
     }

     if (!ast.comments) {
         throw new Error("AST is missing the comments array.");
     }

     if (!ast.loc) {
         throw new Error("AST is missing location information.");
     }

     if (!ast.range) {
         throw new Error("AST is missing range information");
     }
 }

 /**
  * Check to see if its a ES6 export declaration.
  * @param {ASTNode} astNode An AST node.
  * @returns {boolean} whether the given node represents an export declaration.
  * @private
  */
 function looksLikeExport(astNode) {
     return astNode.type === "ExportDefaultDeclaration" || astNode.type === "ExportNamedDeclaration" ||
         astNode.type === "ExportAllDeclaration" || astNode.type === "ExportSpecifier";
 }

 /**
  * Merges two sorted lists into a larger sorted list in O(n) time.
  * @param {Token[]} tokens The list of tokens.
  * @param {Token[]} comments The list of comments.
  * @returns {Token[]} A sorted list of tokens and comments.
  * @private
  */
 function sortedMerge(tokens, comments) {
     const result = [];
     let tokenIndex = 0;
     let commentIndex = 0;

     while (tokenIndex < tokens.length || commentIndex < comments.length) {
         if (commentIndex >= comments.length || tokenIndex < tokens.length && tokens[tokenIndex].range[0] < comments[commentIndex].range[0]) {
             result.push(tokens[tokenIndex++]);
         } else {
             result.push(comments[commentIndex++]);
         }
     }

     return result;
 }

 //------------------------------------------------------------------------------
 // Public Interface
 //------------------------------------------------------------------------------

 class SourceCode extends TokenStore {

     /**
      * Represents parsed source code.
      * @param {string|Object} textOrConfig - The source code text or config object.
      * @param {string} textOrConfig.text - The source code text.
      * @param {ASTNode} textOrConfig.ast - The Program node of the AST representing the code. This AST should be created from the text that BOM was stripped.
      * @param {Object|null} textOrConfig.parserServices - The parser services.
      * @param {ScopeManager|null} textOrConfig.scopeManager - The scope of this source code.
      * @param {Object|null} textOrConfig.visitorKeys - The visitor keys to traverse AST.
      * @param {ASTNode} [astIfNoConfig] - The Program node of the AST representing the code. This AST should be created from the text that BOM was stripped.
      * @constructor
      */
     constructor(textOrConfig, astIfNoConfig) {
         let text, ast, parserServices, scopeManager, visitorKeys;

         // Process overloading.
         if (typeof textOrConfig === "string") {
             text = textOrConfig;
             ast = astIfNoConfig;
         } else if (typeof textOrConfig === "object" && textOrConfig !== null) {
             text = textOrConfig.text;
             ast = textOrConfig.ast;
             parserServices = textOrConfig.parserServices;
             scopeManager = textOrConfig.scopeManager;
             visitorKeys = textOrConfig.visitorKeys;
         }

         validate(ast);
         super(ast.tokens, ast.comments);

         /**
          * The flag to indicate that the source code has Unicode BOM.
          * @type boolean
          */
         this.hasBOM = (text.charCodeAt(0) === 0xFEFF);

         /**
          * The original text source code.
          * BOM was stripped from this text.
          * @type string
          */
         this.text = (this.hasBOM ? text.slice(1) : text);

         /**
          * The parsed AST for the source code.
          * @type ASTNode
          */
         this.ast = ast;

         /**
          * The parser services of this source code.
          * @type {Object}
          */
         this.parserServices = parserServices || {};

         /**
          * The scope of this source code.
          * @type {ScopeManager|null}
          */
         this.scopeManager = scopeManager || null;

         /**
          * The visitor keys to traverse AST.
          * @type {Object}
          */
         this.visitorKeys = visitorKeys || Traverser.DEFAULT_VISITOR_KEYS;

         // Check the source text for the presence of a shebang since it is parsed as a standard line comment.
         const shebangMatched = this.text.match(astUtils.shebangPattern);
         const hasShebang = shebangMatched && ast.comments.length && ast.comments[0].value === shebangMatched[1];

         if (hasShebang) {
             ast.comments[0].type = "Shebang";
         }

         this.tokensAndComments = sortedMerge(ast.tokens, ast.comments);

         /**
          * The source code split into lines according to ECMA-262 specification.
          * This is done to avoid each rule needing to do so separately.
          * @type string[]
          */
         this.lines = [];
         this.lineStartIndices = [0];

         const lineEndingPattern = astUtils.createGlobalLinebreakMatcher();
         let match;

         /*
          * Previously, this was implemented using a regex that
          * matched a sequence of non-linebreak characters followed by a
          * linebreak, then adding the lengths of the matches. However,
          * this caused a catastrophic backtracking issue when the end
          * of a file contained a large number of non-newline characters.
          * To avoid this, the current implementation just matches newlines
          * and uses match.index to get the correct line start indices.
          */
         while ((match = lineEndingPattern.exec(this.text))) {
             this.lines.push(this.text.slice(this.lineStartIndices[this.lineStartIndices.length - 1], match.index));
             this.lineStartIndices.push(match.index + match[0].length);
         }
         this.lines.push(this.text.slice(this.lineStartIndices[this.lineStartIndices.length - 1]));

         // Cache for comments found using getComments().
         this._commentCache = new WeakMap();

         // don't allow modification of this object
         Object.freeze(this);
         Object.freeze(this.lines);
     }

     /**
      * Split the source code into multiple lines based on the line delimiters.
      * @param {string} text Source code as a string.
      * @returns {string[]} Array of source code lines.
      * @public
      */
     static splitLines(text) {
         return text.split(astUtils.createGlobalLinebreakMatcher());
     }

     /**
      * Gets the source code for the given node.
      * @param {ASTNode=} node The AST node to get the text for.
      * @param {int=} beforeCount The number of characters before the node to retrieve.
      * @param {int=} afterCount The number of characters after the node to retrieve.
      * @returns {string} The text representing the AST node.
      * @public
      */
     getText(node, beforeCount, afterCount) {
         if (node) {
             return this.text.slice(Math.max(node.range[0] - (beforeCount || 0), 0),
                 node.range[1] + (afterCount || 0));
         }
         return this.text;
     }

     /**
      * Gets the entire source text split into an array of lines.
      * @returns {Array} The source text as an array of lines.
      * @public
      */
     getLines() {
         return this.lines;
     }

     /**
      * Retrieves an array containing all comments in the source code.
      * @returns {ASTNode[]} An array of comment nodes.
      * @public
      */
     getAllComments() {
         return this.ast.comments;
     }

     /**
      * Gets all comments for the given node.
      * @param {ASTNode} node The AST node to get the comments for.
      * @returns {Object} An object containing a leading and trailing array
      *      of comments indexed by their position.
      * @public
      */
     getComments(node) {
         if (this._commentCache.has(node)) {
             return this._commentCache.get(node);
         }

         const comments = {
             leading: [],
             trailing: []
         };

         /*
          * Return all comments as leading comments of the Program node when
          * there is no executable code.
          */
         if (node.type === "Program") {
             if (node.body.length === 0) {
                 comments.leading = node.comments;
             }
         } else {

             /*
              * Return comments as trailing comments of nodes that only contain
              * comments (to mimic the comment attachment behavior present in Espree).
              */
             if ((node.type === "BlockStatement" || node.type === "ClassBody") && node.body.length === 0 ||
                 node.type === "ObjectExpression" && node.properties.length === 0 ||
                 node.type === "ArrayExpression" && node.elements.length === 0 ||
                 node.type === "SwitchStatement" && node.cases.length === 0
             ) {
                 comments.trailing = this.getTokens(node, {
                     includeComments: true,
                     filter: isCommentToken
                 });
             }

             /*
              * Iterate over tokens before and after node and collect comment tokens.
              * Do not include comments that exist outside of the parent node
              * to avoid duplication.
              */
             let currentToken = this.getTokenBefore(node, { includeComments: true });

             while (currentToken && isCommentToken(currentToken)) {
                 if (node.parent && (currentToken.start < node.parent.start)) {
                     break;
                 }
                 comments.leading.push(currentToken);
                 currentToken = this.getTokenBefore(currentToken, { includeComments: true });
             }

             comments.leading.reverse();

             currentToken = this.getTokenAfter(node, { includeComments: true });

             while (currentToken && isCommentToken(currentToken)) {
                 if (node.parent && (currentToken.end > node.parent.end)) {
                     break;
                 }
                 comments.trailing.push(currentToken);
                 currentToken = this.getTokenAfter(currentToken, { includeComments: true });
             }
         }

         this._commentCache.set(node, comments);
         return comments;
     }

     /**
      * Retrieves the JSDoc comment for a given node.
      * @param {ASTNode} node The AST node to get the comment for.
      * @returns {Token|null} The Block comment token containing the JSDoc comment
      *      for the given node or null if not found.
      * @public
      * @deprecated
      */
     getJSDocComment(node) {

         /**
          * Checks for the presence of a JSDoc comment for the given node and returns it.
          * @param {ASTNode} astNode The AST node to get the comment for.
          * @returns {Token|null} The Block comment token containing the JSDoc comment
          *      for the given node or null if not found.
          * @private
          */
         const findJSDocComment = astNode => {
             const tokenBefore = this.getTokenBefore(astNode, { includeComments: true });

             if (
                 tokenBefore &&
                 isCommentToken(tokenBefore) &&
                 tokenBefore.type === "Block" &&
                 tokenBefore.value.charAt(0) === "*" &&
                 astNode.loc.start.line - tokenBefore.loc.end.line <= 1
             ) {
                 return tokenBefore;
             }

             return null;
         };
         let parent = node.parent;

         switch (node.type) {
             case "ClassDeclaration":
             case "FunctionDeclaration":
                 return findJSDocComment(looksLikeExport(parent) ? parent : node);

             case "ClassExpression":
                 return findJSDocComment(parent.parent);

             case "ArrowFunctionExpression":
             case "FunctionExpression":
                 if (parent.type !== "CallExpression" && parent.type !== "NewExpression") {
                     while (
                         !this.getCommentsBefore(parent).length &&
                         !/Function/u.test(parent.type) &&
                         parent.type !== "MethodDefinition" &&
                         parent.type !== "Property"
                     ) {
                         parent = parent.parent;

                         if (!parent) {
                             break;
                         }
                     }

                     if (parent && parent.type !== "FunctionDeclaration" && parent.type !== "Program") {
                         return findJSDocComment(parent);
                     }
                 }

                 return findJSDocComment(node);

             // falls through
             default:
                 return null;
         }
     }

     /**
      * Gets the deepest node containing a range index.
      * @param {int} index Range index of the desired node.
      * @returns {ASTNode} The node if found or null if not found.
      * @public
      */
     getNodeByRangeIndex(index) {
         let result = null;

         Traverser.traverse(this.ast, {
             visitorKeys: this.visitorKeys,
             enter(node) {
                 if (node.range[0] <= index && index < node.range[1]) {
                     result = node;
                 } else {
                     this.skip();
                 }
             },
             leave(node) {
                 if (node === result) {
                     this.break();
                 }
             }
         });

         return result;
     }

     /**
      * Determines if two tokens have at least one whitespace character
      * between them. This completely disregards comments in making the
      * determination, so comments count as zero-length substrings.
      * @param {Token} first The token to check after.
      * @param {Token} second The token to check before.
      * @returns {boolean} True if there is only space between tokens, false
      *  if there is anything other than whitespace between tokens.
      * @public
      */
     isSpaceBetweenTokens(first, second) {
         const text = this.text.slice(first.range[1], second.range[0]);

         return /\s/u.test(text.replace(/\/\*.*?\*\//gu, ""));
     }

     /**
      * Converts a source text index into a (line, column) pair.
      * @param {number} index The index of a character in a file
      * @returns {Object} A {line, column} location object with a 0-indexed column
      * @public
      */
     getLocFromIndex(index) {
         if (typeof index !== "number") {
             throw new TypeError("Expected `index` to be a number.");
         }

         if (index < 0 || index > this.text.length) {
             throw new RangeError(`Index out of range (requested index ${index}, but source text has length ${this.text.length}).`);
         }

         /*
          * For an argument of this.text.length, return the location one "spot" past the last character
          * of the file. If the last character is a linebreak, the location will be column 0 of the next
          * line; otherwise, the location will be in the next column on the same line.
          *
          * See getIndexFromLoc for the motivation for this special case.
          */
         if (index === this.text.length) {
             return { line: this.lines.length, column: this.lines[this.lines.length - 1].length };
         }

         /*
          * To figure out which line rangeIndex is on, determine the last index at which rangeIndex could
          * be inserted into lineIndices to keep the list sorted.
          */
         const lineNumber = lodash.sortedLastIndex(this.lineStartIndices, index);

         return { line: lineNumber, column: index - this.lineStartIndices[lineNumber - 1] };
     }

     /**
      * Converts a (line, column) pair into a range index.
      * @param {Object} loc A line/column location
      * @param {number} loc.line The line number of the location (1-indexed)
      * @param {number} loc.column The column number of the location (0-indexed)
      * @returns {number} The range index of the location in the file.
      * @public
      */
     getIndexFromLoc(loc) {
         if (typeof loc !== "object" || typeof loc.line !== "number" || typeof loc.column !== "number") {
             throw new TypeError("Expected `loc` to be an object with numeric `line` and `column` properties.");
         }

         if (loc.line <= 0) {
             throw new RangeError(`Line number out of range (line ${loc.line} requested). Line numbers should be 1-based.`);
         }

         if (loc.line > this.lineStartIndices.length) {
             throw new RangeError(`Line number out of range (line ${loc.line} requested, but only ${this.lineStartIndices.length} lines present).`);
         }

         const lineStartIndex = this.lineStartIndices[loc.line - 1];
         const lineEndIndex = loc.line === this.lineStartIndices.length ? this.text.length : this.lineStartIndices[loc.line];
         const positionIndex = lineStartIndex + loc.column;

         /*
          * By design, getIndexFromLoc({ line: lineNum, column: 0 }) should return the start index of
          * the given line, provided that the line number is valid element of this.lines. Since the
          * last element of this.lines is an empty string for files with trailing newlines, add a
          * special case where getting the index for the first location after the end of the file
          * will return the length of the file, rather than throwing an error. This allows rules to
          * use getIndexFromLoc consistently without worrying about edge cases at the end of a file.
          */
         if (
             loc.line === this.lineStartIndices.length && positionIndex > lineEndIndex ||
             loc.line < this.lineStartIndices.length && positionIndex >= lineEndIndex
         ) {
             throw new RangeError(`Column number out of range (column ${loc.column} requested, but the length of line ${loc.line} is ${lineEndIndex - lineStartIndex}).`);
         }

         return positionIndex;
     }
 }

 module.exports = SourceCode;
	/**
	* @fileoverview Abstraction of JavaScript source code.
	* @author Nicholas C. Zakas
	*/
	"use strict";

	//------------------------------------------------------------------------------
	// Requirements
	//------------------------------------------------------------------------------

	const
	{ isCommentToken } = require("eslint-utils"),
	TokenStore = require("./token-store"),
	astUtils = require("../shared/ast-utils"),
	Traverser = require("../shared/traverser"),
	lodash = require("lodash");

	//------------------------------------------------------------------------------
	// Private
	//------------------------------------------------------------------------------

	/**
	* Validates that the given AST has the required information.
	* @param {ASTNode} ast The Program node of the AST to check.
	* @throws {Error} If the AST doesn't contain the correct information.
	* @returns {void}
	* @private
	*/
	function validate(ast) {
	if (!ast.tokens) {
	throw new Error("AST is missing the tokens array.");
	}

	if (!ast.comments) {
	throw new Error("AST is missing the comments array.");
	}

	if (!ast.loc) {
	throw new Error("AST is missing location information.");
	}

	if (!ast.range) {
	throw new Error("AST is missing range information");
	}
	}

	/**
	* Check to see if its a ES6 export declaration.
	* @param {ASTNode} astNode An AST node.
	* @returns {boolean} whether the given node represents an export declaration.
	* @private
	*/
	function looksLikeExport(astNode) {
	return astNode.type === "ExportDefaultDeclaration" \|\| astNode.type === "ExportNamedDeclaration" \|\|
	astNode.type === "ExportAllDeclaration" \|\| astNode.type === "ExportSpecifier";
	}

	/**
	* Merges two sorted lists into a larger sorted list in O(n) time.
	* @param {Token[]} tokens The list of tokens.
	* @param {Token[]} comments The list of comments.
	* @returns {Token[]} A sorted list of tokens and comments.
	* @private
	*/
	function sortedMerge(tokens, comments) {
	const result = [];
	let tokenIndex = 0;
	let commentIndex = 0;

	while (tokenIndex < tokens.length \|\| commentIndex < comments.length) {
	if (commentIndex >= comments.length \|\| tokenIndex < tokens.length && tokens[tokenIndex].range[0] < comments[commentIndex].range[0]) {
	result.push(tokens[tokenIndex++]);
	} else {
	result.push(comments[commentIndex++]);
	}
	}

	return result;
	}

	//------------------------------------------------------------------------------
	// Public Interface
	//------------------------------------------------------------------------------

	class SourceCode extends TokenStore {

	/**
	* Represents parsed source code.
	* @param {string\|Object} textOrConfig - The source code text or config object.
	* @param {string} textOrConfig.text - The source code text.
	* @param {ASTNode} textOrConfig.ast - The Program node of the AST representing the code. This AST should be created from the text that BOM was stripped.
	* @param {Object\|null} textOrConfig.parserServices - The parser services.
	* @param {ScopeManager\|null} textOrConfig.scopeManager - The scope of this source code.
	* @param {Object\|null} textOrConfig.visitorKeys - The visitor keys to traverse AST.
	* @param {ASTNode} [astIfNoConfig] - The Program node of the AST representing the code. This AST should be created from the text that BOM was stripped.
	* @constructor
	*/
	constructor(textOrConfig, astIfNoConfig) {
	let text, ast, parserServices, scopeManager, visitorKeys;

	// Process overloading.
	if (typeof textOrConfig === "string") {
	text = textOrConfig;
	ast = astIfNoConfig;
	} else if (typeof textOrConfig === "object" && textOrConfig !== null) {
	text = textOrConfig.text;
	ast = textOrConfig.ast;
	parserServices = textOrConfig.parserServices;
	scopeManager = textOrConfig.scopeManager;
	visitorKeys = textOrConfig.visitorKeys;
	}

	validate(ast);
	super(ast.tokens, ast.comments);

	/**
	* The flag to indicate that the source code has Unicode BOM.
	* @type boolean
	*/
	this.hasBOM = (text.charCodeAt(0) === 0xFEFF);

	/**
	* The original text source code.
	* BOM was stripped from this text.
	* @type string
	*/
	this.text = (this.hasBOM ? text.slice(1) : text);

	/**
	* The parsed AST for the source code.
	* @type ASTNode
	*/
	this.ast = ast;

	/**
	* The parser services of this source code.
	* @type {Object}
	*/
	this.parserServices = parserServices \|\| {};

	/**
	* The scope of this source code.
	* @type {ScopeManager\|null}
	*/
	this.scopeManager = scopeManager \|\| null;

	/**
	* The visitor keys to traverse AST.
	* @type {Object}
	*/
	this.visitorKeys = visitorKeys \|\| Traverser.DEFAULT_VISITOR_KEYS;

	// Check the source text for the presence of a shebang since it is parsed as a standard line comment.
	const shebangMatched = this.text.match(astUtils.shebangPattern);
	const hasShebang = shebangMatched && ast.comments.length && ast.comments[0].value === shebangMatched[1];

	if (hasShebang) {
	ast.comments[0].type = "Shebang";
	}

	this.tokensAndComments = sortedMerge(ast.tokens, ast.comments);

	/**
	* The source code split into lines according to ECMA-262 specification.
	* This is done to avoid each rule needing to do so separately.
	* @type string[]
	*/
	this.lines = [];
	this.lineStartIndices = [0];

	const lineEndingPattern = astUtils.createGlobalLinebreakMatcher();
	let match;

	/*
	* Previously, this was implemented using a regex that
	* matched a sequence of non-linebreak characters followed by a
	* linebreak, then adding the lengths of the matches. However,
	* this caused a catastrophic backtracking issue when the end
	* of a file contained a large number of non-newline characters.
	* To avoid this, the current implementation just matches newlines
	* and uses match.index to get the correct line start indices.
	*/
	while ((match = lineEndingPattern.exec(this.text))) {
	this.lines.push(this.text.slice(this.lineStartIndices[this.lineStartIndices.length - 1], match.index));
	this.lineStartIndices.push(match.index + match[0].length);
	}
	this.lines.push(this.text.slice(this.lineStartIndices[this.lineStartIndices.length - 1]));

	// Cache for comments found using getComments().
	this._commentCache = new WeakMap();

	// don't allow modification of this object
	Object.freeze(this);
	Object.freeze(this.lines);
	}

	/**
	* Split the source code into multiple lines based on the line delimiters.
	* @param {string} text Source code as a string.
	* @returns {string[]} Array of source code lines.
	* @public
	*/
	static splitLines(text) {
	return text.split(astUtils.createGlobalLinebreakMatcher());
	}

	/**
	* Gets the source code for the given node.
	* @param {ASTNode=} node The AST node to get the text for.
	* @param {int=} beforeCount The number of characters before the node to retrieve.
	* @param {int=} afterCount The number of characters after the node to retrieve.
	* @returns {string} The text representing the AST node.
	* @public
	*/
	getText(node, beforeCount, afterCount) {
	if (node) {
	return this.text.slice(Math.max(node.range[0] - (beforeCount \|\| 0), 0),
	node.range[1] + (afterCount \|\| 0));
	}
	return this.text;
	}

	/**
	* Gets the entire source text split into an array of lines.
	* @returns {Array} The source text as an array of lines.
	* @public
	*/
	getLines() {
	return this.lines;
	}

	/**
	* Retrieves an array containing all comments in the source code.
	* @returns {ASTNode[]} An array of comment nodes.
	* @public
	*/
	getAllComments() {
	return this.ast.comments;
	}

	/**
	* Gets all comments for the given node.
	* @param {ASTNode} node The AST node to get the comments for.
	* @returns {Object} An object containing a leading and trailing array
	* of comments indexed by their position.
	* @public
	*/
	getComments(node) {
	if (this._commentCache.has(node)) {
	return this._commentCache.get(node);
	}

	const comments = {
	leading: [],
	trailing: []
	};

	/*
	* Return all comments as leading comments of the Program node when
	* there is no executable code.
	*/
	if (node.type === "Program") {
	if (node.body.length === 0) {
	comments.leading = node.comments;
	}
	} else {

	/*
	* Return comments as trailing comments of nodes that only contain
	* comments (to mimic the comment attachment behavior present in Espree).
	*/
	if ((node.type === "BlockStatement" \|\| node.type === "ClassBody") && node.body.length === 0 \|\|
	node.type === "ObjectExpression" && node.properties.length === 0 \|\|
	node.type === "ArrayExpression" && node.elements.length === 0 \|\|
	node.type === "SwitchStatement" && node.cases.length === 0
	) {
	comments.trailing = this.getTokens(node, {
	includeComments: true,
	filter: isCommentToken
	});
	}

	/*
	* Iterate over tokens before and after node and collect comment tokens.
	* Do not include comments that exist outside of the parent node
	* to avoid duplication.
	*/
	let currentToken = this.getTokenBefore(node, { includeComments: true });

	while (currentToken && isCommentToken(currentToken)) {
	if (node.parent && (currentToken.start < node.parent.start)) {
	break;
	}
	comments.leading.push(currentToken);
	currentToken = this.getTokenBefore(currentToken, { includeComments: true });
	}

	comments.leading.reverse();

	currentToken = this.getTokenAfter(node, { includeComments: true });

	while (currentToken && isCommentToken(currentToken)) {
	if (node.parent && (currentToken.end > node.parent.end)) {
	break;
	}
	comments.trailing.push(currentToken);
	currentToken = this.getTokenAfter(currentToken, { includeComments: true });
	}
	}

	this._commentCache.set(node, comments);
	return comments;
	}

	/**
	* Retrieves the JSDoc comment for a given node.
	* @param {ASTNode} node The AST node to get the comment for.
	* @returns {Token\|null} The Block comment token containing the JSDoc comment
	* for the given node or null if not found.
	* @public
	* @deprecated
	*/
	getJSDocComment(node) {

	/**
	* Checks for the presence of a JSDoc comment for the given node and returns it.
	* @param {ASTNode} astNode The AST node to get the comment for.
	* @returns {Token\|null} The Block comment token containing the JSDoc comment
	* for the given node or null if not found.
	* @private
	*/
	const findJSDocComment = astNode => {
	const tokenBefore = this.getTokenBefore(astNode, { includeComments: true });

	if (
	tokenBefore &&
	isCommentToken(tokenBefore) &&
	tokenBefore.type === "Block" &&
	tokenBefore.value.charAt(0) === "*" &&
	astNode.loc.start.line - tokenBefore.loc.end.line <= 1
	) {
	return tokenBefore;
	}

	return null;
	};
	let parent = node.parent;

	switch (node.type) {
	case "ClassDeclaration":
	case "FunctionDeclaration":
	return findJSDocComment(looksLikeExport(parent) ? parent : node);

	case "ClassExpression":
	return findJSDocComment(parent.parent);

	case "ArrowFunctionExpression":
	case "FunctionExpression":
	if (parent.type !== "CallExpression" && parent.type !== "NewExpression") {
	while (
	!this.getCommentsBefore(parent).length &&
	!/Function/u.test(parent.type) &&
	parent.type !== "MethodDefinition" &&
	parent.type !== "Property"
	) {
	parent = parent.parent;

	if (!parent) {
	break;
	}
	}

	if (parent && parent.type !== "FunctionDeclaration" && parent.type !== "Program") {
	return findJSDocComment(parent);
	}
	}

	return findJSDocComment(node);

	// falls through
	default:
	return null;
	}
	}

	/**
	* Gets the deepest node containing a range index.
	* @param {int} index Range index of the desired node.
	* @returns {ASTNode} The node if found or null if not found.
	* @public
	*/
	getNodeByRangeIndex(index) {
	let result = null;

	Traverser.traverse(this.ast, {
	visitorKeys: this.visitorKeys,
	enter(node) {
	if (node.range[0] <= index && index < node.range[1]) {
	result = node;
	} else {
	this.skip();
	}
	},
	leave(node) {
	if (node === result) {
	this.break();
	}
	}
	});

	return result;
	}

	/**
	* Determines if two tokens have at least one whitespace character
	* between them. This completely disregards comments in making the
	* determination, so comments count as zero-length substrings.
	* @param {Token} first The token to check after.
	* @param {Token} second The token to check before.
	* @returns {boolean} True if there is only space between tokens, false
	* if there is anything other than whitespace between tokens.
	* @public
	*/
	isSpaceBetweenTokens(first, second) {
	const text = this.text.slice(first.range[1], second.range[0]);

	return /\s/u.test(text.replace(/\/\.?\*\//gu, ""));
	}

	/**
	* Converts a source text index into a (line, column) pair.
	* @param {number} index The index of a character in a file
	* @returns {Object} A {line, column} location object with a 0-indexed column
	* @public
	*/
	getLocFromIndex(index) {
	if (typeof index !== "number") {
	throw new TypeError("Expected `index` to be a number.");
	}

	if (index < 0 \|\| index > this.text.length) {
	throw new RangeError(`Index out of range (requested index ${index}, but source text has length ${this.text.length}).`);
	}

	/*
	* For an argument of this.text.length, return the location one "spot" past the last character
	* of the file. If the last character is a linebreak, the location will be column 0 of the next
	* line; otherwise, the location will be in the next column on the same line.
	*
	* See getIndexFromLoc for the motivation for this special case.
	*/
	if (index === this.text.length) {
	return { line: this.lines.length, column: this.lines[this.lines.length - 1].length };
	}

	/*
	* To figure out which line rangeIndex is on, determine the last index at which rangeIndex could
	* be inserted into lineIndices to keep the list sorted.
	*/
	const lineNumber = lodash.sortedLastIndex(this.lineStartIndices, index);

	return { line: lineNumber, column: index - this.lineStartIndices[lineNumber - 1] };
	}

	/**
	* Converts a (line, column) pair into a range index.
	* @param {Object} loc A line/column location
	* @param {number} loc.line The line number of the location (1-indexed)
	* @param {number} loc.column The column number of the location (0-indexed)
	* @returns {number} The range index of the location in the file.
	* @public
	*/
	getIndexFromLoc(loc) {
	if (typeof loc !== "object" \|\| typeof loc.line !== "number" \|\| typeof loc.column !== "number") {
	throw new TypeError("Expected `loc` to be an object with numeric `line` and `column` properties.");
	}

	if (loc.line <= 0) {
	throw new RangeError(`Line number out of range (line ${loc.line} requested). Line numbers should be 1-based.`);
	}

	if (loc.line > this.lineStartIndices.length) {
	throw new RangeError(`Line number out of range (line ${loc.line} requested, but only ${this.lineStartIndices.length} lines present).`);
	}

	const lineStartIndex = this.lineStartIndices[loc.line - 1];
	const lineEndIndex = loc.line === this.lineStartIndices.length ? this.text.length : this.lineStartIndices[loc.line];
	const positionIndex = lineStartIndex + loc.column;

	/*
	* By design, getIndexFromLoc({ line: lineNum, column: 0 }) should return the start index of
	* the given line, provided that the line number is valid element of this.lines. Since the
	* last element of this.lines is an empty string for files with trailing newlines, add a
	* special case where getting the index for the first location after the end of the file
	* will return the length of the file, rather than throwing an error. This allows rules to
	* use getIndexFromLoc consistently without worrying about edge cases at the end of a file.
	*/
	if (
	loc.line === this.lineStartIndices.length && positionIndex > lineEndIndex \|\|
	loc.line < this.lineStartIndices.length && positionIndex >= lineEndIndex
	) {
	throw new RangeError(`Column number out of range (column ${loc.column} requested, but the length of line ${loc.line} is ${lineEndIndex - lineStartIndex}).`);
	}

	return positionIndex;
	}
	}

	module.exports = SourceCode;