@stagas/wasm-sourcemap

Fix AssemblyScript generated WebAssembly source map URLs.

AssemblyScript can emit a sourceMappingURL custom section in a .wasm binary. This package reads, removes, or replaces that section directly from a WASM byte buffer.

Install

npm install @stagas/wasm-sourcemap

Usage

import { readFile, writeFile } from 'node:fs/promises'
import { wasmSourceMap } from '@stagas/wasm-sourcemap'

const wasm = await readFile('build/module.wasm')

const url = wasmSourceMap.getSourceMapURL(wasm)
console.log(url)

const fixed = wasmSourceMap.setSourceMapURL(wasm, 'module.wasm.map')
await writeFile('build/module.wasm', fixed)

API

wasmSourceMap.getSourceMapURL(buf)

Returns the source map URL from the WASM sourceMappingURL custom section, or null when the section does not exist.

const url = wasmSourceMap.getSourceMapURL(wasm)

wasmSourceMap.removeSourceMapURL(buf)

Returns a new Uint8Array with the sourceMappingURL custom section removed. If the section does not exist, the original bytes are returned as a Uint8Array.

const withoutSourceMap = wasmSourceMap.removeSourceMapURL(wasm)

wasmSourceMap.setSourceMapURL(buf, url)

Returns a new Uint8Array with the sourceMappingURL custom section set to url. Any existing sourceMappingURL section is removed first.

const withSourceMap = wasmSourceMap.setSourceMapURL(wasm, 'module.wasm.map')

License

MIT