https://github.com/lgrignon/sourcemap-builder

Forked from https://github.com/google/closure-compiler's SourceMapGenerator
https://github.com/lgrignon/sourcemap-builder

Last synced: about 7 hours ago
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Forked from https://github.com/google/closure-compiler's SourceMapGenerator

• Host: GitHub
• URL: https://github.com/lgrignon/sourcemap-builder
• Owner: lgrignon
• Created: 2019-12-24T10:35:22.000Z (almost 5 years ago)
• Default Branch: master
• Last Pushed: 2022-05-20T21:21:25.000Z (over 2 years ago)
• Last Synced: 2023-02-26T21:22:13.087Z (over 1 year ago)
• Language: Java
• Size: 35.2 KB
• Stars: 2
• Watchers: 2
• Forks: 0
• Open Issues: 1
• Metadata Files:
  • Readme: README.md

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README

        
Parse, generate and combine Source Map files.

# Examples

Parse Source Map

``` Java

// Parsing source map data.

SourceMap map = new SourceMapImpl(

    "{\n" +

    "  \"version\":3,\n" +

    "  \"sources\":[\"/script.js\"],\n" +

    "  \"names\":[],\n" +

    "  \"mappings\":\"AAAA,KAAU;;AAIV,KAKA;\"\n" +

    "}"

);

// Get single mapping.

System.out.println("Single mapping: " + map.getMapping(0, 5));

// Iterate over each mapping.

System.out.println("All mappings:");

map.eachMapping(new SourceMap.EachMappingCallback() { public void apply(Mapping mapping) {

    System.out.println(mapping);

}});

```

Generate Source Map

``` Java

SourceMap map = new SourceMapImpl();

map.addMapping(0, 0, 0, 0, "/script.js");

map.addMapping(0, 5, 0, 10, "/script.js");

map.addMapping(2, 0, 4, 0, "/script.js");

map.addMapping(2, 5, 9, 0, "/script.js");

System.out.println("Generated Source Map: " + map.generate());

```

Add offset for Source Map, needed when some postprocessing applied to generated file. Like wrapping in `try/catch`

block and adding one line before and after.

``` Java

SourceMap map = new SourceMapImpl();

map.addMapping(0, 0, 0, 0, "/script.js");

SourceMap mapWithOffset = Util.offset(map, 1);

System.out.println("Source Map after applying offset: " + mapWithOffset.generateForHumans());

```

Rebase source map, needed when multiple transformation applied to the source. In example

below two transformation applied CoffeeScript -> JavaScript -> Minified JavaScript.

``` Java

SourceMap coffeeToJs = new SourceMapImpl();

coffeeToJs.addMapping(1, 0, 0, 0, "/script.coffee");

SourceMap jsToMinJs = new SourceMapImpl();

jsToMinJs.addMapping(2, 0, 1, 0, "/script.js");

SourceMap minJsToCoffee = Util.rebase(jsToMinJs, coffeeToJs);

System.out.println("SourceMap for CoffeeScript -> JS -> MinJS: " + minJsToCoffee.generateForHumans());

```

Join multiple Source Map in one file, needed when files joined in batch. In example below

two files `a.js` and `b.js` joined in `batch.js`.

 

``` Java

// Source Map for a.js

String a = "var a = 0;";

SourceMap mapA = new SourceMapImpl();

mapA.addMapping(0, 0, 0, 0, "/a.js");

// Source Map for b.js

String b = "var b = 0;";

SourceMap mapB = new SourceMapImpl();

mapB.addMapping(0, 0, 0, 0, "/b.js");

// Source Map for a.js and b.js joined into batch.js.

SourceMapJoiner joiner = Util.joiner();

joiner.addSourceMap(mapA, Util.countLines(a), 0);

joiner.addSourceMap(mapB, Util.countLines(b), 0);

SourceMap batchMap = joiner.join();

System.out.println("Source Map for batch.js: " + batchMap.generateForHumans());

```

Note: `offset`, `join` and `rebase` could be combined in arbitrary order, so it is possible to create Source Map

for minified batch of CoffeeScript files etc.

# Credits

Some code based on the code from Google Closure Compiler.

# License

Released under the Apache License, Version 2.0