| /** | |
|  * @fileoverview Translates tokens between Acorn format and Esprima format. | |
|  * @author Nicholas C. Zakas | |
|  */ | |
| 
 | |
| //------------------------------------------------------------------------------ | |
| // Requirements | |
| //------------------------------------------------------------------------------ | |
|  | |
| // none! | |
|  | |
| //------------------------------------------------------------------------------ | |
| // Private | |
| //------------------------------------------------------------------------------ | |
|  | |
| 
 | |
| // Esprima Token Types | |
| const Token = { | |
|     Boolean: "Boolean", | |
|     EOF: "<end>", | |
|     Identifier: "Identifier", | |
|     PrivateIdentifier: "PrivateIdentifier", | |
|     Keyword: "Keyword", | |
|     Null: "Null", | |
|     Numeric: "Numeric", | |
|     Punctuator: "Punctuator", | |
|     String: "String", | |
|     RegularExpression: "RegularExpression", | |
|     Template: "Template", | |
|     JSXIdentifier: "JSXIdentifier", | |
|     JSXText: "JSXText" | |
| }; | |
| 
 | |
| /** | |
|  * Converts part of a template into an Esprima token. | |
|  * @param {AcornToken[]} tokens The Acorn tokens representing the template. | |
|  * @param {string} code The source code. | |
|  * @returns {EsprimaToken} The Esprima equivalent of the template token. | |
|  * @private | |
|  */ | |
| function convertTemplatePart(tokens, code) { | |
|     const firstToken = tokens[0], | |
|         lastTemplateToken = tokens[tokens.length - 1]; | |
| 
 | |
|     const token = { | |
|         type: Token.Template, | |
|         value: code.slice(firstToken.start, lastTemplateToken.end) | |
|     }; | |
| 
 | |
|     if (firstToken.loc) { | |
|         token.loc = { | |
|             start: firstToken.loc.start, | |
|             end: lastTemplateToken.loc.end | |
|         }; | |
|     } | |
| 
 | |
|     if (firstToken.range) { | |
|         token.start = firstToken.range[0]; | |
|         token.end = lastTemplateToken.range[1]; | |
|         token.range = [token.start, token.end]; | |
|     } | |
| 
 | |
|     return token; | |
| } | |
| 
 | |
| /** | |
|  * Contains logic to translate Acorn tokens into Esprima tokens. | |
|  * @param {Object} acornTokTypes The Acorn token types. | |
|  * @param {string} code The source code Acorn is parsing. This is necessary | |
|  *      to correct the "value" property of some tokens. | |
|  * @constructor | |
|  */ | |
| function TokenTranslator(acornTokTypes, code) { | |
| 
 | |
|     // token types | |
|     this._acornTokTypes = acornTokTypes; | |
| 
 | |
|     // token buffer for templates | |
|     this._tokens = []; | |
| 
 | |
|     // track the last curly brace | |
|     this._curlyBrace = null; | |
| 
 | |
|     // the source code | |
|     this._code = code; | |
| 
 | |
| } | |
| 
 | |
| TokenTranslator.prototype = { | |
|     constructor: TokenTranslator, | |
| 
 | |
|     /** | |
|      * Translates a single Esprima token to a single Acorn token. This may be | |
|      * inaccurate due to how templates are handled differently in Esprima and | |
|      * Acorn, but should be accurate for all other tokens. | |
|      * @param {AcornToken} token The Acorn token to translate. | |
|      * @param {Object} extra Espree extra object. | |
|      * @returns {EsprimaToken} The Esprima version of the token. | |
|      */ | |
|     translate(token, extra) { | |
| 
 | |
|         const type = token.type, | |
|             tt = this._acornTokTypes; | |
| 
 | |
|         if (type === tt.name) { | |
|             token.type = Token.Identifier; | |
| 
 | |
|             // TODO: See if this is an Acorn bug | |
|             if (token.value === "static") { | |
|                 token.type = Token.Keyword; | |
|             } | |
| 
 | |
|             if (extra.ecmaVersion > 5 && (token.value === "yield" || token.value === "let")) { | |
|                 token.type = Token.Keyword; | |
|             } | |
| 
 | |
|         } else if (type === tt.privateId) { | |
|             token.type = Token.PrivateIdentifier; | |
| 
 | |
|         } else if (type === tt.semi || type === tt.comma || | |
|                  type === tt.parenL || type === tt.parenR || | |
|                  type === tt.braceL || type === tt.braceR || | |
|                  type === tt.dot || type === tt.bracketL || | |
|                  type === tt.colon || type === tt.question || | |
|                  type === tt.bracketR || type === tt.ellipsis || | |
|                  type === tt.arrow || type === tt.jsxTagStart || | |
|                  type === tt.incDec || type === tt.starstar || | |
|                  type === tt.jsxTagEnd || type === tt.prefix || | |
|                  type === tt.questionDot || | |
|                  (type.binop && !type.keyword) || | |
|                  type.isAssign) { | |
| 
 | |
|             token.type = Token.Punctuator; | |
|             token.value = this._code.slice(token.start, token.end); | |
|         } else if (type === tt.jsxName) { | |
|             token.type = Token.JSXIdentifier; | |
|         } else if (type.label === "jsxText" || type === tt.jsxAttrValueToken) { | |
|             token.type = Token.JSXText; | |
|         } else if (type.keyword) { | |
|             if (type.keyword === "true" || type.keyword === "false") { | |
|                 token.type = Token.Boolean; | |
|             } else if (type.keyword === "null") { | |
|                 token.type = Token.Null; | |
|             } else { | |
|                 token.type = Token.Keyword; | |
|             } | |
|         } else if (type === tt.num) { | |
|             token.type = Token.Numeric; | |
|             token.value = this._code.slice(token.start, token.end); | |
|         } else if (type === tt.string) { | |
| 
 | |
|             if (extra.jsxAttrValueToken) { | |
|                 extra.jsxAttrValueToken = false; | |
|                 token.type = Token.JSXText; | |
|             } else { | |
|                 token.type = Token.String; | |
|             } | |
| 
 | |
|             token.value = this._code.slice(token.start, token.end); | |
|         } else if (type === tt.regexp) { | |
|             token.type = Token.RegularExpression; | |
|             const value = token.value; | |
| 
 | |
|             token.regex = { | |
|                 flags: value.flags, | |
|                 pattern: value.pattern | |
|             }; | |
|             token.value = `/${value.pattern}/${value.flags}`; | |
|         } | |
| 
 | |
|         return token; | |
|     }, | |
| 
 | |
|     /** | |
|      * Function to call during Acorn's onToken handler. | |
|      * @param {AcornToken} token The Acorn token. | |
|      * @param {Object} extra The Espree extra object. | |
|      * @returns {void} | |
|      */ | |
|     onToken(token, extra) { | |
| 
 | |
|         const tt = this._acornTokTypes, | |
|             tokens = extra.tokens, | |
|             templateTokens = this._tokens; | |
| 
 | |
|         /** | |
|          * Flushes the buffered template tokens and resets the template | |
|          * tracking. | |
|          * @returns {void} | |
|          * @private | |
|          */ | |
|         const translateTemplateTokens = () => { | |
|             tokens.push(convertTemplatePart(this._tokens, this._code)); | |
|             this._tokens = []; | |
|         }; | |
| 
 | |
|         if (token.type === tt.eof) { | |
| 
 | |
|             // might be one last curlyBrace | |
|             if (this._curlyBrace) { | |
|                 tokens.push(this.translate(this._curlyBrace, extra)); | |
|             } | |
| 
 | |
|             return; | |
|         } | |
| 
 | |
|         if (token.type === tt.backQuote) { | |
| 
 | |
|             // if there's already a curly, it's not part of the template | |
|             if (this._curlyBrace) { | |
|                 tokens.push(this.translate(this._curlyBrace, extra)); | |
|                 this._curlyBrace = null; | |
|             } | |
| 
 | |
|             templateTokens.push(token); | |
| 
 | |
|             // it's the end | |
|             if (templateTokens.length > 1) { | |
|                 translateTemplateTokens(); | |
|             } | |
| 
 | |
|             return; | |
|         } | |
|         if (token.type === tt.dollarBraceL) { | |
|             templateTokens.push(token); | |
|             translateTemplateTokens(); | |
|             return; | |
|         } | |
|         if (token.type === tt.braceR) { | |
| 
 | |
|             // if there's already a curly, it's not part of the template | |
|             if (this._curlyBrace) { | |
|                 tokens.push(this.translate(this._curlyBrace, extra)); | |
|             } | |
| 
 | |
|             // store new curly for later | |
|             this._curlyBrace = token; | |
|             return; | |
|         } | |
|         if (token.type === tt.template || token.type === tt.invalidTemplate) { | |
|             if (this._curlyBrace) { | |
|                 templateTokens.push(this._curlyBrace); | |
|                 this._curlyBrace = null; | |
|             } | |
| 
 | |
|             templateTokens.push(token); | |
|             return; | |
|         } | |
| 
 | |
|         if (this._curlyBrace) { | |
|             tokens.push(this.translate(this._curlyBrace, extra)); | |
|             this._curlyBrace = null; | |
|         } | |
| 
 | |
|         tokens.push(this.translate(token, extra)); | |
|     } | |
| }; | |
| 
 | |
| //------------------------------------------------------------------------------ | |
| // Public | |
| //------------------------------------------------------------------------------ | |
|  | |
| export default TokenTranslator;
 |