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diff --git a/tools/eslint/node_modules/source-map/README.md b/tools/eslint/node_modules/source-map/README.md new file mode 100644 index 0000000000..b7c6786cef --- /dev/null +++ b/tools/eslint/node_modules/source-map/README.md @@ -0,0 +1,510 @@ +# Source Map + +This is a library to generate and consume the source map format +[described here][format]. + +This library is written in the Asynchronous Module Definition format, and works +in the following environments: + +* Modern Browsers supporting ECMAScript 5 (either after the build, or with an + AMD loader such as RequireJS) + +* Inside Firefox (as a JSM file, after the build) + +* With NodeJS versions 0.8.X and higher + +## Node + + $ npm install source-map + +## Building from Source (for everywhere else) + +Install Node and then run + + $ git clone https://fitzgen@github.com/mozilla/source-map.git + $ cd source-map + $ npm link . + +Next, run + + $ node Makefile.dryice.js + +This should spew a bunch of stuff to stdout, and create the following files: + +* `dist/source-map.js` - The unminified browser version. + +* `dist/source-map.min.js` - The minified browser version. + +* `dist/SourceMap.jsm` - The JavaScript Module for inclusion in Firefox source. + +## Examples + +### Consuming a source map + +```js +var rawSourceMap = { + version: 3, + file: 'min.js', + names: ['bar', 'baz', 'n'], + sources: ['one.js', 'two.js'], + sourceRoot: 'http://example.com/www/js/', + mappings: 'CAAC,IAAI,IAAM,SAAUA,GAClB,OAAOC,IAAID;CCDb,IAAI,IAAM,SAAUE,GAClB,OAAOA' +}; + +var smc = new SourceMapConsumer(rawSourceMap); + +console.log(smc.sources); +// [ 'http://example.com/www/js/one.js', +// 'http://example.com/www/js/two.js' ] + +console.log(smc.originalPositionFor({ + line: 2, + column: 28 +})); +// { source: 'http://example.com/www/js/two.js', +// line: 2, +// column: 10, +// name: 'n' } + +console.log(smc.generatedPositionFor({ + source: 'http://example.com/www/js/two.js', + line: 2, + column: 10 +})); +// { line: 2, column: 28 } + +smc.eachMapping(function (m) { + // ... +}); +``` + +### Generating a source map + +In depth guide: +[**Compiling to JavaScript, and Debugging with Source Maps**](https://hacks.mozilla.org/2013/05/compiling-to-javascript-and-debugging-with-source-maps/) + +#### With SourceNode (high level API) + +```js +function compile(ast) { + switch (ast.type) { + case 'BinaryExpression': + return new SourceNode( + ast.location.line, + ast.location.column, + ast.location.source, + [compile(ast.left), " + ", compile(ast.right)] + ); + case 'Literal': + return new SourceNode( + ast.location.line, + ast.location.column, + ast.location.source, + String(ast.value) + ); + // ... + default: + throw new Error("Bad AST"); + } +} + +var ast = parse("40 + 2", "add.js"); +console.log(compile(ast).toStringWithSourceMap({ + file: 'add.js' +})); +// { code: '40 + 2', +// map: [object SourceMapGenerator] } +``` + +#### With SourceMapGenerator (low level API) + +```js +var map = new SourceMapGenerator({ + file: "source-mapped.js" +}); + +map.addMapping({ + generated: { + line: 10, + column: 35 + }, + source: "foo.js", + original: { + line: 33, + column: 2 + }, + name: "christopher" +}); + +console.log(map.toString()); +// '{"version":3,"file":"source-mapped.js","sources":["foo.js"],"names":["christopher"],"mappings":";;;;;;;;;mCAgCEA"}' +``` + +## API + +Get a reference to the module: + +```js +// NodeJS +var sourceMap = require('source-map'); + +// Browser builds +var sourceMap = window.sourceMap; + +// Inside Firefox +let sourceMap = {}; +Components.utils.import('resource:///modules/devtools/SourceMap.jsm', sourceMap); +``` + +### SourceMapConsumer + +A SourceMapConsumer instance represents a parsed source map which we can query +for information about the original file positions by giving it a file position +in the generated source. + +#### new SourceMapConsumer(rawSourceMap) + +The only parameter is the raw source map (either as a string which can be +`JSON.parse`'d, or an object). According to the spec, source maps have the +following attributes: + +* `version`: Which version of the source map spec this map is following. + +* `sources`: An array of URLs to the original source files. + +* `names`: An array of identifiers which can be referrenced by individual + mappings. + +* `sourceRoot`: Optional. The URL root from which all sources are relative. + +* `sourcesContent`: Optional. An array of contents of the original source files. + +* `mappings`: A string of base64 VLQs which contain the actual mappings. + +* `file`: Optional. The generated filename this source map is associated with. + +#### SourceMapConsumer.prototype.computeColumnSpans() + +Compute the last column for each generated mapping. The last column is +inclusive. + +#### SourceMapConsumer.prototype.originalPositionFor(generatedPosition) + +Returns the original source, line, and column information for the generated +source's line and column positions provided. The only argument is an object with +the following properties: + +* `line`: The line number in the generated source. + +* `column`: The column number in the generated source. + +* `bias`: Either `SourceMapConsumer.GREATEST_LOWER_BOUND` or + `SourceMapConsumer.LEAST_UPPER_BOUND`. Specifies whether to return the closest + element that is smaller than or greater than the one we are searching for, + respectively, if the exact element cannot be found. Defaults to + `SourceMapConsumer.GREATEST_LOWER_BOUND`. + +and an object is returned with the following properties: + +* `source`: The original source file, or null if this information is not + available. + +* `line`: The line number in the original source, or null if this information is + not available. + +* `column`: The column number in the original source, or null or null if this + information is not available. + +* `name`: The original identifier, or null if this information is not available. + +#### SourceMapConsumer.prototype.generatedPositionFor(originalPosition) + +Returns the generated line and column information for the original source, +line, and column positions provided. The only argument is an object with +the following properties: + +* `source`: The filename of the original source. + +* `line`: The line number in the original source. + +* `column`: The column number in the original source. + +and an object is returned with the following properties: + +* `line`: The line number in the generated source, or null. + +* `column`: The column number in the generated source, or null. + +#### SourceMapConsumer.prototype.allGeneratedPositionsFor(originalPosition) + +Returns all generated line and column information for the original source, line, +and column provided. If no column is provided, returns all mappings +corresponding to a either the line we are searching for or the next closest line +that has any mappings. Otherwise, returns all mappings corresponding to the +given line and either the column we are searching for or the next closest column +that has any offsets. + +The only argument is an object with the following properties: + +* `source`: The filename of the original source. + +* `line`: The line number in the original source. + +* `column`: Optional. The column number in the original source. + +and an array of objects is returned, each with the following properties: + +* `line`: The line number in the generated source, or null. + +* `column`: The column number in the generated source, or null. + +#### SourceMapConsumer.prototype.hasContentsOfAllSources() + +Return true if we have the embedded source content for every source listed in +the source map, false otherwise. + +In other words, if this method returns `true`, then `smc.sourceContentFor(s)` +will succeed for every source `s` in `smc.sources`. + +#### SourceMapConsumer.prototype.sourceContentFor(source[, returnNullOnMissing]) + +Returns the original source content for the source provided. The only +argument is the URL of the original source file. + +If the source content for the given source is not found, then an error is +thrown. Optionally, pass `true` as the second param to have `null` returned +instead. + +#### SourceMapConsumer.prototype.eachMapping(callback, context, order) + +Iterate over each mapping between an original source/line/column and a +generated line/column in this source map. + +* `callback`: The function that is called with each mapping. Mappings have the + form `{ source, generatedLine, generatedColumn, originalLine, originalColumn, + name }` + +* `context`: Optional. If specified, this object will be the value of `this` + every time that `callback` is called. + +* `order`: Either `SourceMapConsumer.GENERATED_ORDER` or + `SourceMapConsumer.ORIGINAL_ORDER`. Specifies whether you want to iterate over + the mappings sorted by the generated file's line/column order or the + original's source/line/column order, respectively. Defaults to + `SourceMapConsumer.GENERATED_ORDER`. + +### SourceMapGenerator + +An instance of the SourceMapGenerator represents a source map which is being +built incrementally. + +#### new SourceMapGenerator([startOfSourceMap]) + +You may pass an object with the following properties: + +* `file`: The filename of the generated source that this source map is + associated with. + +* `sourceRoot`: A root for all relative URLs in this source map. + +* `skipValidation`: Optional. When `true`, disables validation of mappings as + they are added. This can improve performance but should be used with + discretion, as a last resort. Even then, one should avoid using this flag when + running tests, if possible. + +#### SourceMapGenerator.fromSourceMap(sourceMapConsumer) + +Creates a new SourceMapGenerator based on a SourceMapConsumer + +* `sourceMapConsumer` The SourceMap. + +#### SourceMapGenerator.prototype.addMapping(mapping) + +Add a single mapping from original source line and column to the generated +source's line and column for this source map being created. The mapping object +should have the following properties: + +* `generated`: An object with the generated line and column positions. + +* `original`: An object with the original line and column positions. + +* `source`: The original source file (relative to the sourceRoot). + +* `name`: An optional original token name for this mapping. + +#### SourceMapGenerator.prototype.setSourceContent(sourceFile, sourceContent) + +Set the source content for an original source file. + +* `sourceFile` the URL of the original source file. + +* `sourceContent` the content of the source file. + +#### SourceMapGenerator.prototype.applySourceMap(sourceMapConsumer[, sourceFile[, sourceMapPath]]) + +Applies a SourceMap for a source file to the SourceMap. +Each mapping to the supplied source file is rewritten using the +supplied SourceMap. Note: The resolution for the resulting mappings +is the minimium of this map and the supplied map. + +* `sourceMapConsumer`: The SourceMap to be applied. + +* `sourceFile`: Optional. The filename of the source file. + If omitted, sourceMapConsumer.file will be used, if it exists. + Otherwise an error will be thrown. + +* `sourceMapPath`: Optional. The dirname of the path to the SourceMap + to be applied. If relative, it is relative to the SourceMap. + + This parameter is needed when the two SourceMaps aren't in the same + directory, and the SourceMap to be applied contains relative source + paths. If so, those relative source paths need to be rewritten + relative to the SourceMap. + + If omitted, it is assumed that both SourceMaps are in the same directory, + thus not needing any rewriting. (Supplying `'.'` has the same effect.) + +#### SourceMapGenerator.prototype.toString() + +Renders the source map being generated to a string. + +### SourceNode + +SourceNodes provide a way to abstract over interpolating and/or concatenating +snippets of generated JavaScript source code, while maintaining the line and +column information associated between those snippets and the original source +code. This is useful as the final intermediate representation a compiler might +use before outputting the generated JS and source map. + +#### new SourceNode([line, column, source[, chunk[, name]]]) + +* `line`: The original line number associated with this source node, or null if + it isn't associated with an original line. + +* `column`: The original column number associated with this source node, or null + if it isn't associated with an original column. + +* `source`: The original source's filename; null if no filename is provided. + +* `chunk`: Optional. Is immediately passed to `SourceNode.prototype.add`, see + below. + +* `name`: Optional. The original identifier. + +#### SourceNode.fromStringWithSourceMap(code, sourceMapConsumer[, relativePath]) + +Creates a SourceNode from generated code and a SourceMapConsumer. + +* `code`: The generated code + +* `sourceMapConsumer` The SourceMap for the generated code + +* `relativePath` The optional path that relative sources in `sourceMapConsumer` + should be relative to. + +#### SourceNode.prototype.add(chunk) + +Add a chunk of generated JS to this source node. + +* `chunk`: A string snippet of generated JS code, another instance of + `SourceNode`, or an array where each member is one of those things. + +#### SourceNode.prototype.prepend(chunk) + +Prepend a chunk of generated JS to this source node. + +* `chunk`: A string snippet of generated JS code, another instance of + `SourceNode`, or an array where each member is one of those things. + +#### SourceNode.prototype.setSourceContent(sourceFile, sourceContent) + +Set the source content for a source file. This will be added to the +`SourceMap` in the `sourcesContent` field. + +* `sourceFile`: The filename of the source file + +* `sourceContent`: The content of the source file + +#### SourceNode.prototype.walk(fn) + +Walk over the tree of JS snippets in this node and its children. The walking +function is called once for each snippet of JS and is passed that snippet and +the its original associated source's line/column location. + +* `fn`: The traversal function. + +#### SourceNode.prototype.walkSourceContents(fn) + +Walk over the tree of SourceNodes. The walking function is called for each +source file content and is passed the filename and source content. + +* `fn`: The traversal function. + +#### SourceNode.prototype.join(sep) + +Like `Array.prototype.join` except for SourceNodes. Inserts the separator +between each of this source node's children. + +* `sep`: The separator. + +#### SourceNode.prototype.replaceRight(pattern, replacement) + +Call `String.prototype.replace` on the very right-most source snippet. Useful +for trimming whitespace from the end of a source node, etc. + +* `pattern`: The pattern to replace. + +* `replacement`: The thing to replace the pattern with. + +#### SourceNode.prototype.toString() + +Return the string representation of this source node. Walks over the tree and +concatenates all the various snippets together to one string. + +#### SourceNode.prototype.toStringWithSourceMap([startOfSourceMap]) + +Returns the string representation of this tree of source nodes, plus a +SourceMapGenerator which contains all the mappings between the generated and +original sources. + +The arguments are the same as those to `new SourceMapGenerator`. + +## Tests + +[![Build Status](https://travis-ci.org/mozilla/source-map.png?branch=master)](https://travis-ci.org/mozilla/source-map) + +Install NodeJS version 0.8.0 or greater, then run `node test/run-tests.js`. + +To add new tests, create a new file named `test/test-<your new test name>.js` +and export your test functions with names that start with "test", for example + +```js +exports["test doing the foo bar"] = function (assert, util) { + ... +}; +``` + +The new test will be located automatically when you run the suite. + +The `util` argument is the test utility module located at `test/source-map/util`. + +The `assert` argument is a cut down version of node's assert module. You have +access to the following assertion functions: + +* `doesNotThrow` + +* `equal` + +* `ok` + +* `strictEqual` + +* `throws` + +(The reason for the restricted set of test functions is because we need the +tests to run inside Firefox's test suite as well and so the assert module is +shimmed in that environment. See `build/assert-shim.js`.) + +[format]: https://docs.google.com/document/d/1U1RGAehQwRypUTovF1KRlpiOFze0b-_2gc6fAH0KY0k/edit +[feature]: https://wiki.mozilla.org/DevTools/Features/SourceMap +[Dryice]: https://github.com/mozilla/dryice |