What is @volar/source-map?
@volar/source-map is a package designed to handle source maps, which are used to map the transformed code back to the original source code. This is particularly useful in debugging and development environments where you need to trace errors or understand the flow of the code.
What are @volar/source-map's main functionalities?
Creating Source Maps
This feature allows you to create a new source map. The code sample demonstrates how to generate a source map and add a mapping to it.
const { SourceMapGenerator } = require('@volar/source-map');
const map = new SourceMapGenerator({ file: 'output.js' });
map.addMapping({
generated: { line: 1, column: 5 },
source: 'input.js',
original: { line: 1, column: 5 },
name: 'example'
});
console.log(map.toString());
Parsing Source Maps
This feature allows you to parse an existing source map. The code sample demonstrates how to use the SourceMapConsumer to read and interpret a raw source map.
const { SourceMapConsumer } = require('@volar/source-map');
const rawSourceMap = {
version: 3,
file: 'min.js',
sources: ['one.js', 'two.js'],
names: ['foo', 'bar'],
mappings: 'AAgBC,SAAQ,CAAEA'
};
SourceMapConsumer.with(rawSourceMap, null, consumer => {
console.log(consumer.sources);
console.log(consumer.originalPositionFor({ line: 1, column: 5 }));
});
Combining Source Maps
This feature allows you to combine multiple source maps into one. The code sample demonstrates how to create two source maps and then combine them into a single source map.
const { SourceMapGenerator, SourceMapConsumer } = require('@volar/source-map');
const map1 = new SourceMapGenerator({ file: 'output1.js' });
map1.addMapping({
generated: { line: 1, column: 5 },
source: 'input1.js',
original: { line: 1, column: 5 },
name: 'example1'
});
const map2 = new SourceMapGenerator({ file: 'output2.js' });
map2.addMapping({
generated: { line: 2, column: 10 },
source: 'input2.js',
original: { line: 2, column: 10 },
name: 'example2'
});
const combinedMap = SourceMapGenerator.fromSourceMap(new SourceMapConsumer(map1.toString()));
combinedMap.applySourceMap(new SourceMapConsumer(map2.toString()));
console.log(combinedMap.toString());
Other packages similar to @volar/source-map
source-map
The 'source-map' package is a widely-used library for generating and consuming source maps. It provides similar functionalities to @volar/source-map, such as creating, parsing, and combining source maps. However, 'source-map' is more established and has a larger user base.
source-map-support
The 'source-map-support' package provides source map support for stack traces in node.js. While it also deals with source maps, its primary focus is on enhancing error stack traces with source map information, making it slightly different in scope compared to @volar/source-map.
webpack
Webpack is a module bundler that includes built-in support for source maps. While it is not solely focused on source maps, it provides extensive functionalities for generating and managing source maps as part of its bundling process. It is more comprehensive and complex compared to @volar/source-map.