sourav-das/stem-separator

1# convert-source-map [![Build Status][ci-image]][ci-url]2 3Converts a source-map from/to  different formats and allows adding/changing properties.4 5```js6var convert = require('convert-source-map');7 8var json = convert9  .fromComment('//# sourceMappingURL=data:application/json;base64,eyJ2ZXJzaW9uIjozLCJmaWxlIjoiYnVpbGQvZm9vLm1pbi5qcyIsInNvdXJjZXMiOlsic3JjL2Zvby5qcyJdLCJuYW1lcyI6W10sIm1hcHBpbmdzIjoiQUFBQSIsInNvdXJjZVJvb3QiOiIvIn0=')10  .toJSON();11 12var modified = convert13  .fromComment('//# sourceMappingURL=data:application/json;base64,eyJ2ZXJzaW9uIjozLCJmaWxlIjoiYnVpbGQvZm9vLm1pbi5qcyIsInNvdXJjZXMiOlsic3JjL2Zvby5qcyJdLCJuYW1lcyI6W10sIm1hcHBpbmdzIjoiQUFBQSIsInNvdXJjZVJvb3QiOiIvIn0=')14  .setProperty('sources', [ 'SRC/FOO.JS' ])15  .toJSON();16 17console.log(json);18console.log(modified);19```20 21```json22{"version":3,"file":"build/foo.min.js","sources":["src/foo.js"],"names":[],"mappings":"AAAA","sourceRoot":"/"}23{"version":3,"file":"build/foo.min.js","sources":["SRC/FOO.JS"],"names":[],"mappings":"AAAA","sourceRoot":"/"}24```25 26## Upgrading27 28Prior to v2.0.0, the `fromMapFileComment` and `fromMapFileSource` functions took a String directory path and used that to resolve & read the source map file from the filesystem. However, this made the library limited to nodejs environments and broke on sources with querystrings.29 30In v2.0.0, you now need to pass a function that does the file reading. It will receive the source filename as a String that you can resolve to a filesystem path, URL, or anything else.31 32If you are using `convert-source-map` in nodejs and want the previous behavior, you'll use a function like such:33 34```diff35+ var fs = require('fs'); // Import the fs module to read a file36+ var path = require('path'); // Import the path module to resolve a path against your directory37- var conv = convert.fromMapFileSource(css, '../my-dir');38+ var conv = convert.fromMapFileSource(css, function (filename) {39+   return fs.readFileSync(path.resolve('../my-dir', filename), 'utf-8');40+ });41```42 43## API44 45### fromObject(obj)46 47Returns source map converter from given object.48 49### fromJSON(json)50 51Returns source map converter from given json string.52 53### fromURI(uri)54 55Returns source map converter from given uri encoded json string.56 57### fromBase64(base64)58 59Returns source map converter from given base64 encoded json string.60 61### fromComment(comment)62 63Returns source map converter from given base64 or uri encoded json string prefixed with `//# sourceMappingURL=...`.64 65### fromMapFileComment(comment, readMap)66 67Returns source map converter from given `filename` by parsing `//# sourceMappingURL=filename`.68 69`readMap` must be a function which receives the source map filename and returns either a String or Buffer of the source map (if read synchronously), or a `Promise` containing a String or Buffer of the source map (if read asynchronously).70 71If `readMap` doesn't return a `Promise`, `fromMapFileComment` will return a source map converter synchronously.72 73If `readMap` returns a `Promise`, `fromMapFileComment` will also return `Promise`. The `Promise` will be either resolved with the source map converter or rejected with an error.74 75#### Examples76 77**Synchronous read in Node.js:**78 79```js80var convert = require('convert-source-map');81var fs = require('fs');82 83function readMap(filename) {84  return fs.readFileSync(filename, 'utf8');85}86 87var json = convert88  .fromMapFileComment('//# sourceMappingURL=map-file-comment.css.map', readMap)89  .toJSON();90console.log(json);91```92 93 94**Asynchronous read in Node.js:**95 96```js97var convert = require('convert-source-map');98var { promises: fs } = require('fs'); // Notice the `promises` import99 100function readMap(filename) {101  return fs.readFile(filename, 'utf8');102}103 104var converter = await convert.fromMapFileComment('//# sourceMappingURL=map-file-comment.css.map', readMap)105var json = converter.toJSON();106console.log(json);107```108 109**Asynchronous read in the browser:**110 111```js112var convert = require('convert-source-map');113 114async function readMap(url) {115  const res = await fetch(url);116  return res.text();117}118 119const converter = await convert.fromMapFileComment('//# sourceMappingURL=map-file-comment.css.map', readMap)120var json = converter.toJSON();121console.log(json);122```123 124### fromSource(source)125 126Finds last sourcemap comment in file and returns source map converter or returns `null` if no source map comment was found.127 128### fromMapFileSource(source, readMap)129 130Finds last sourcemap comment in file and returns source map converter or returns `null` if no source map comment was found.131 132`readMap` must be a function which receives the source map filename and returns either a String or Buffer of the source map (if read synchronously), or a `Promise` containing a String or Buffer of the source map (if read asynchronously).133 134If `readMap` doesn't return a `Promise`, `fromMapFileSource` will return a source map converter synchronously.135 136If `readMap` returns a `Promise`, `fromMapFileSource` will also return `Promise`. The `Promise` will be either resolved with the source map converter or rejected with an error.137 138### toObject()139 140Returns a copy of the underlying source map.141 142### toJSON([space])143 144Converts source map to json string. If `space` is given (optional), this will be passed to145[JSON.stringify](https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/JSON/stringify) when the146JSON string is generated.147 148### toURI()149 150Converts source map to uri encoded json string.151 152### toBase64()153 154Converts source map to base64 encoded json string.155 156### toComment([options])157 158Converts source map to an inline comment that can be appended to the source-file.159 160By default, the comment is formatted like: `//# sourceMappingURL=...`, which you would161normally see in a JS source file.162 163When `options.encoding == 'uri'`, the data will be uri encoded, otherwise they will be base64 encoded.164 165When `options.multiline == true`, the comment is formatted like: `/*# sourceMappingURL=... */`, which you would find in a CSS source file.166 167### addProperty(key, value)168 169Adds given property to the source map. Throws an error if property already exists.170 171### setProperty(key, value)172 173Sets given property to the source map. If property doesn't exist it is added, otherwise its value is updated.174 175### getProperty(key)176 177Gets given property of the source map.178 179### removeComments(src)180 181Returns `src` with all source map comments removed182 183### removeMapFileComments(src)184 185Returns `src` with all source map comments pointing to map files removed.186 187### commentRegex188 189Provides __a fresh__ RegExp each time it is accessed. Can be used to find source map comments.190 191Breaks down a source map comment into groups: Groups: 1: media type, 2: MIME type, 3: charset, 4: encoding, 5: data.192 193### mapFileCommentRegex194 195Provides __a fresh__ RegExp each time it is accessed. Can be used to find source map comments pointing to map files.196 197### generateMapFileComment(file, [options])198 199Returns a comment that links to an external source map via `file`.200 201By default, the comment is formatted like: `//# sourceMappingURL=...`, which you would normally see in a JS source file.202 203When `options.multiline == true`, the comment is formatted like: `/*# sourceMappingURL=... */`, which you would find in a CSS source file.204 205[ci-url]: https://github.com/thlorenz/convert-source-map/actions?query=workflow:ci206[ci-image]: https://img.shields.io/github/workflow/status/thlorenz/convert-source-map/CI?style=flat-square207