esbuild 0.14.48

v0.14.48

on Node.js NPM

Enable using esbuild in Deno via WebAssembly (#2323)

The native implementation of esbuild is much faster than the WebAssembly version, but some people don't want to give Deno the --allow-run permission necessary to run esbuild and are ok waiting longer for their builds to finish when using the WebAssembly backend. With this release, you can now use esbuild via WebAssembly in Deno. To do this you will need to import from wasm.js instead of mod.js:

import * as esbuild from 'https://deno.land/x/esbuild@v0.14.48/wasm.js'
const ts = 'let test: boolean = true'
const result = await esbuild.transform(ts, { loader: 'ts' })
console.log('result:', result)

Make sure you run Deno with --allow-net so esbuild can download the WebAssembly module. Using esbuild like this starts up a worker thread that runs esbuild in parallel (unless you call esbuild.initialize({ worker: false }) to tell esbuild to run on the main thread). If you want to, you can call esbuild.stop() to terminate the worker if you won't be using esbuild anymore and you want to reclaim the memory.

Note that Deno appears to have a bug where background WebAssembly optimization can prevent the process from exiting for many seconds. If you are trying to use Deno and WebAssembly to run esbuild quickly, you may need to manually call Deno.exit(0) after your code has finished running.

Add support for font file MIME types (#2337)

This release adds support for font file MIME types to esbuild, which means they are now recognized by the built-in local web server and they are now used when a font file is loaded using the dataurl loader. The full set of newly-added file extension MIME type mappings is as follows:

• .eot => application/vnd.ms-fontobject
• .otf => font/otf
• .sfnt => font/sfnt
• .ttf => font/ttf
• .woff => font/woff
• .woff2 => font/woff2

Remove "use strict"; when targeting ESM (#2347)

All ES module code is automatically in strict mode, so a "use strict"; directive is unnecessary. With this release, esbuild will now remove the "use strict"; directive if the output format is ESM. This change makes the generated output file a few bytes smaller:

// Original code
'use strict'
export let foo = 123

// Old output (with --format=esm --minify)
"use strict";let t=123;export{t as foo};

// New output (with --format=esm --minify)
let t=123;export{t as foo};

Attempt to have esbuild work with Deno on FreeBSD (#2356)

Deno doesn't support FreeBSD, but it's possible to build Deno for FreeBSD with some additional patches on top. This release of esbuild changes esbuild's Deno installer to download esbuild's FreeBSD binary in this situation. This configuration is unsupported although in theory everything should work.

Add some more target JavaScript engines (#2357)

This release adds the Rhino and Hermes JavaScript engines to the set of engine identifiers that can be passed to the --target flag. You can use this to restrict esbuild to only using JavaScript features that are supported on those engines in the output files that esbuild generates.