1 | /**
|
2 | * @fileoverview Abstraction of JavaScript source code.
|
3 | * @author Nicholas C. Zakas
|
4 | */
|
5 | ;
|
6 |
|
7 | //------------------------------------------------------------------------------
|
8 | // Requirements
|
9 | //------------------------------------------------------------------------------
|
10 |
|
11 | const createTokenStore = require("../token-store.js"),
|
12 | Traverser = require("./traverser");
|
13 |
|
14 | //------------------------------------------------------------------------------
|
15 | // Private
|
16 | //------------------------------------------------------------------------------
|
17 |
|
18 | /**
|
19 | * Validates that the given AST has the required information.
|
20 | * @param {ASTNode} ast The Program node of the AST to check.
|
21 | * @throws {Error} If the AST doesn't contain the correct information.
|
22 | * @returns {void}
|
23 | * @private
|
24 | */
|
25 | function validate(ast) {
|
26 |
|
27 | if (!ast.tokens) {
|
28 | throw new Error("AST is missing the tokens array.");
|
29 | }
|
30 |
|
31 | if (!ast.comments) {
|
32 | throw new Error("AST is missing the comments array.");
|
33 | }
|
34 |
|
35 | if (!ast.loc) {
|
36 | throw new Error("AST is missing location information.");
|
37 | }
|
38 |
|
39 | if (!ast.range) {
|
40 | throw new Error("AST is missing range information");
|
41 | }
|
42 | }
|
43 |
|
44 | /**
|
45 | * Finds a JSDoc comment node in an array of comment nodes.
|
46 | * @param {ASTNode[]} comments The array of comment nodes to search.
|
47 | * @param {int} line Line number to look around
|
48 | * @returns {ASTNode} The node if found, null if not.
|
49 | * @private
|
50 | */
|
51 | function findJSDocComment(comments, line) {
|
52 |
|
53 | if (comments) {
|
54 | for (let i = comments.length - 1; i >= 0; i--) {
|
55 | if (comments[i].type === "Block" && comments[i].value.charAt(0) === "*") {
|
56 |
|
57 | if (line - comments[i].loc.end.line <= 1) {
|
58 | return comments[i];
|
59 | } else {
|
60 | break;
|
61 | }
|
62 | }
|
63 | }
|
64 | }
|
65 |
|
66 | return null;
|
67 | }
|
68 |
|
69 | /**
|
70 | * Check to see if its a ES6 export declaration
|
71 | * @param {ASTNode} astNode - any node
|
72 | * @returns {boolean} whether the given node represents a export declaration
|
73 | * @private
|
74 | */
|
75 | function looksLikeExport(astNode) {
|
76 | return astNode.type === "ExportDefaultDeclaration" || astNode.type === "ExportNamedDeclaration" ||
|
77 | astNode.type === "ExportAllDeclaration" || astNode.type === "ExportSpecifier";
|
78 | }
|
79 |
|
80 |
|
81 | //------------------------------------------------------------------------------
|
82 | // Public Interface
|
83 | //------------------------------------------------------------------------------
|
84 |
|
85 | /**
|
86 | * Represents parsed source code.
|
87 | * @param {string} text - The source code text.
|
88 | * @param {ASTNode} ast - The Program node of the AST representing the code. This AST should be created from the text that BOM was stripped.
|
89 | * @constructor
|
90 | */
|
91 | function SourceCode(text, ast) {
|
92 | validate(ast);
|
93 |
|
94 | /**
|
95 | * The flag to indicate that the source code has Unicode BOM.
|
96 | * @type boolean
|
97 | */
|
98 | this.hasBOM = (text.charCodeAt(0) === 0xFEFF);
|
99 |
|
100 | /**
|
101 | * The original text source code.
|
102 | * BOM was stripped from this text.
|
103 | * @type string
|
104 | */
|
105 | this.text = (this.hasBOM ? text.slice(1) : text);
|
106 |
|
107 | /**
|
108 | * The parsed AST for the source code.
|
109 | * @type ASTNode
|
110 | */
|
111 | this.ast = ast;
|
112 |
|
113 | /**
|
114 | * The source code split into lines according to ECMA-262 specification.
|
115 | * This is done to avoid each rule needing to do so separately.
|
116 | * @type string[]
|
117 | */
|
118 | this.lines = SourceCode.splitLines(this.text);
|
119 |
|
120 | this.tokensAndComments = ast.tokens.concat(ast.comments).sort(function(left, right) {
|
121 | return left.range[0] - right.range[0];
|
122 | });
|
123 |
|
124 | // create token store methods
|
125 | const tokenStore = createTokenStore(ast.tokens);
|
126 |
|
127 | Object.keys(tokenStore).forEach(function(methodName) {
|
128 | this[methodName] = tokenStore[methodName];
|
129 | }, this);
|
130 |
|
131 | const tokensAndCommentsStore = createTokenStore(this.tokensAndComments);
|
132 |
|
133 | this.getTokenOrCommentBefore = tokensAndCommentsStore.getTokenBefore;
|
134 | this.getTokenOrCommentAfter = tokensAndCommentsStore.getTokenAfter;
|
135 |
|
136 | // don't allow modification of this object
|
137 | Object.freeze(this);
|
138 | Object.freeze(this.lines);
|
139 | }
|
140 |
|
141 | /**
|
142 | * Split the source code into multiple lines based on the line delimiters
|
143 | * @param {string} text Source code as a string
|
144 | * @returns {string[]} Array of source code lines
|
145 | * @public
|
146 | */
|
147 | SourceCode.splitLines = function(text) {
|
148 | return text.split(/\r\n|\r|\n|\u2028|\u2029/g);
|
149 | };
|
150 |
|
151 | SourceCode.prototype = {
|
152 | constructor: SourceCode,
|
153 |
|
154 | /**
|
155 | * Gets the source code for the given node.
|
156 | * @param {ASTNode=} node The AST node to get the text for.
|
157 | * @param {int=} beforeCount The number of characters before the node to retrieve.
|
158 | * @param {int=} afterCount The number of characters after the node to retrieve.
|
159 | * @returns {string} The text representing the AST node.
|
160 | */
|
161 | getText(node, beforeCount, afterCount) {
|
162 | if (node) {
|
163 | return this.text.slice(Math.max(node.range[0] - (beforeCount || 0), 0),
|
164 | node.range[1] + (afterCount || 0));
|
165 | } else {
|
166 | return this.text;
|
167 | }
|
168 |
|
169 | },
|
170 |
|
171 | /**
|
172 | * Gets the entire source text split into an array of lines.
|
173 | * @returns {Array} The source text as an array of lines.
|
174 | */
|
175 | getLines() {
|
176 | return this.lines;
|
177 | },
|
178 |
|
179 | /**
|
180 | * Retrieves an array containing all comments in the source code.
|
181 | * @returns {ASTNode[]} An array of comment nodes.
|
182 | */
|
183 | getAllComments() {
|
184 | return this.ast.comments;
|
185 | },
|
186 |
|
187 | /**
|
188 | * Gets all comments for the given node.
|
189 | * @param {ASTNode} node The AST node to get the comments for.
|
190 | * @returns {Object} The list of comments indexed by their position.
|
191 | * @public
|
192 | */
|
193 | getComments(node) {
|
194 |
|
195 | let leadingComments = node.leadingComments || [];
|
196 | const trailingComments = node.trailingComments || [];
|
197 |
|
198 | /*
|
199 | * espree adds a "comments" array on Program nodes rather than
|
200 | * leadingComments/trailingComments. Comments are only left in the
|
201 | * Program node comments array if there is no executable code.
|
202 | */
|
203 | if (node.type === "Program") {
|
204 | if (node.body.length === 0) {
|
205 | leadingComments = node.comments;
|
206 | }
|
207 | }
|
208 |
|
209 | return {
|
210 | leading: leadingComments,
|
211 | trailing: trailingComments
|
212 | };
|
213 | },
|
214 |
|
215 | /**
|
216 | * Retrieves the JSDoc comment for a given node.
|
217 | * @param {ASTNode} node The AST node to get the comment for.
|
218 | * @returns {ASTNode} The BlockComment node containing the JSDoc for the
|
219 | * given node or null if not found.
|
220 | * @public
|
221 | */
|
222 | getJSDocComment(node) {
|
223 |
|
224 | let parent = node.parent;
|
225 |
|
226 | switch (node.type) {
|
227 | case "ClassDeclaration":
|
228 | case "FunctionDeclaration":
|
229 | if (looksLikeExport(parent)) {
|
230 | return findJSDocComment(parent.leadingComments, parent.loc.start.line);
|
231 | }
|
232 | return findJSDocComment(node.leadingComments, node.loc.start.line);
|
233 |
|
234 | case "ClassExpression":
|
235 | return findJSDocComment(parent.parent.leadingComments, parent.parent.loc.start.line);
|
236 |
|
237 | case "ArrowFunctionExpression":
|
238 | case "FunctionExpression":
|
239 |
|
240 | if (parent.type !== "CallExpression" && parent.type !== "NewExpression") {
|
241 | while (parent && !parent.leadingComments && !/Function/.test(parent.type) && parent.type !== "MethodDefinition" && parent.type !== "Property") {
|
242 | parent = parent.parent;
|
243 | }
|
244 |
|
245 | return parent && (parent.type !== "FunctionDeclaration") ? findJSDocComment(parent.leadingComments, parent.loc.start.line) : null;
|
246 | } else if (node.leadingComments) {
|
247 | return findJSDocComment(node.leadingComments, node.loc.start.line);
|
248 | }
|
249 |
|
250 | // falls through
|
251 |
|
252 | default:
|
253 | return null;
|
254 | }
|
255 | },
|
256 |
|
257 | /**
|
258 | * Gets the deepest node containing a range index.
|
259 | * @param {int} index Range index of the desired node.
|
260 | * @returns {ASTNode} The node if found or null if not found.
|
261 | */
|
262 | getNodeByRangeIndex(index) {
|
263 | let result = null,
|
264 | resultParent = null;
|
265 | const traverser = new Traverser();
|
266 |
|
267 | traverser.traverse(this.ast, {
|
268 | enter(node, parent) {
|
269 | if (node.range[0] <= index && index < node.range[1]) {
|
270 | result = node;
|
271 | resultParent = parent;
|
272 | } else {
|
273 | this.skip();
|
274 | }
|
275 | },
|
276 | leave(node) {
|
277 | if (node === result) {
|
278 | this.break();
|
279 | }
|
280 | }
|
281 | });
|
282 |
|
283 | return result ? Object.assign({parent: resultParent}, result) : null;
|
284 | },
|
285 |
|
286 | /**
|
287 | * Determines if two tokens have at least one whitespace character
|
288 | * between them. This completely disregards comments in making the
|
289 | * determination, so comments count as zero-length substrings.
|
290 | * @param {Token} first The token to check after.
|
291 | * @param {Token} second The token to check before.
|
292 | * @returns {boolean} True if there is only space between tokens, false
|
293 | * if there is anything other than whitespace between tokens.
|
294 | */
|
295 | isSpaceBetweenTokens(first, second) {
|
296 | const text = this.text.slice(first.range[1], second.range[0]);
|
297 |
|
298 | return /\s/.test(text.replace(/\/\*.*?\*\//g, ""));
|
299 | }
|
300 | };
|
301 |
|
302 |
|
303 | module.exports = SourceCode;
|