Replace @tootallnate/quickjs-emscripten with quickjs-wasi

[TooTallNate]

Summary

Replaces @tootallnate/quickjs-emscripten with quickjs-wasi across all three PAC-related packages. quickjs-wasi is a lighter-weight QuickJS WASM runtime built on quickjs-ng with WASI reactor mode, supporting VM state snapshotting/restore.

Changes

• degenerator: compile() now takes a QuickJS instance directly (no more qjs.newContext() — the instance IS the context). resolvePromise() returns {value}|{error} instead of VmCallResult. Promise bridging calls executePendingJobs() after resolve/reject.
• pac-resolver: createPacResolver() takes QuickJS instead of QuickJSWASMModule. Switched to workspace:* dependency on degenerator.
• pac-proxy-agent: QuickJS.create() replaces getQuickJS(). quickjs-wasi is a runtime dependency. Switched to workspace:* dependency on pac-resolver.
• Tests: Updated error message assertion for quickjs-ng which formats identifier errors slightly differently.

Test Results

All tests pass:

• degenerator: 18/18
• pac-resolver: 63/63
• pac-proxy-agent: 14/14

[changeset-bot]

🦋 Changeset detected

Latest commit: e053c6e

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 4 packages

Name	Type
degenerator	Minor
pac-resolver	Minor
pac-proxy-agent	Minor
proxy-agent	Patch

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Project	Deployment	Actions	Updated (UTC)
proxy-agents	Ready	Preview	Mar 6, 2026 11:26pm

[Copilot]

Pull request overview

This PR migrates the PAC-related packages off @tootallnate/quickjs-emscripten and onto quickjs-wasi, updating the VM construction/usage and aligning tests with quickjs-ng error formatting.

Changes:

• Swapped QuickJS implementation to quickjs-wasi and updated call sites to use QuickJS.create() and the new promise/job APIs.
• Updated degenerator.compile() to accept a QuickJS instance directly and adapted promise resolution/error handling.
• Updated internal workspace dependencies (pac-proxy-agent → pac-resolver, pac-resolver → degenerator) and refreshed tests/error assertions.

Reviewed changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
pnpm-lock.yaml	Replaces quickjs-emscripten entries with quickjs-wasi and updates workspace links.
packages/pac-resolver/test/test.ts	Uses QuickJS.create() and updates identifier error assertion.
packages/pac-resolver/src/index.ts	Updates createPacResolver() to accept QuickJS from quickjs-wasi.
packages/pac-resolver/package.json	Switches degenerator to workspace:* and adds quickjs-wasi for development/tests.
packages/pac-proxy-agent/src/index.ts	Uses QuickJS.create() when loading PAC resolver.
packages/pac-proxy-agent/package.json	Moves to workspace:* pac-resolver and adds quickjs-wasi dependency.
packages/degenerator/test/test.ts	Uses QuickJS.create(), disposes VM in teardown, updates identifier error assertion.
packages/degenerator/src/compile.ts	Reworks compile flow to use quickjs-wasi VM API and updated promise bridging.
packages/degenerator/package.json	Adds quickjs-wasi for development/tests.

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

Comments suppressed due to low confidence (1)

packages/pac-proxy-agent/src/index.ts:149

• loadResolver() creates a new QuickJS instance unconditionally, but if the PAC file hash matches and you reuse this.resolver, the newly created qjs is never disposed. This will leak WASM/VM memory over time. Consider computing the hash first (before creating the VM), or explicitly disposing the unused qjs before returning.

			// (Re)load the contents of the PAC file URI
			const [qjs, code] = await Promise.all([
				QuickJS.create(),
				this.loadPacFile(),
			]);

			// Create a sha1 hash of the JS code
			const hash = crypto.createHash('sha1').update(code).digest('hex');

			if (this.resolver && this.resolverHash === hash) {
				debug(
					'Same sha1 hash for code - contents have not changed, reusing previous proxy resolver'
				);
				return this.resolver;
			}

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