featmigrate action to native ESM and upgrade @actions/* to ESM majors#2
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featmigrate action to native ESM and upgrade @actions/* to ESM majors#2
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Migrate the action from CommonJS to native ESM so that it can consume the ESM-only majors of the `@actions/*` toolkit packages (and any future ESM-only dependencies) without a transpile-to-CJS step. Tooling changes: - Set `"type": "module"` and emit ESM throughout. - Replace `@vercel/ncc` (which cannot emit ESM) with Rollup (`@rollup/plugin-typescript`, `-node-resolve`, `-commonjs`, `-json`, `-terser`). Output is still `lib/main/index.js` so `action.yml` is unchanged. - Drop `ts-node`/`tsx` in favour of Node 24's native TypeScript type-stripping (`.ts` files execute directly under `node`). Mocha invokes tests without any TypeScript loader. - Replace `nyc` + `@istanbuljs/nyc-config-typescript` with `c8` for coverage, which needs no source instrumentation under ESM. `.nycrc.json` is retained as the config file (c8 reads it natively for nyc compatibility). - Switch relative imports throughout src/, test/, and misc/ to use `.ts` extensions and set `allowImportingTsExtensions` + `rewriteRelativeImportExtensions` in `tsconfig.json` so both Node and Rollup resolve them directly. - Update `misc/generate-docs.ts` to ESM (JSON import attribute, `import.meta.url` in place of `__dirname`). Source-code adjustments to keep sinon stubbing working under ESM: - Modules that expose runtime values used from other modules now `export default` a plain object alongside their named exports, and call sites use `import foo from './foo.ts'; foo.bar()`. ES module named-export bindings are read-only and cannot be rebound by sinon, so stubbing has to operate on a shared mutable object. - `@actions/*` packages are imported via default (`import core from '@actions/core'`) rather than as a namespace (`import * as core`). The default import resolves to the underlying CJS `module.exports` (mutable and stub-friendly), whereas a namespace import is a frozen snapshot that doesn't reflect sinon mutations. - `node:fs` / `node:fs/promises` are imported as defaults for the same reason. Docs: - Update `.github/copilot-instructions.md` to describe the new toolchain (Rollup, Node 24 native TS, c8) and document the ESM stubbing patterns. BREAKING CHANGE: The action is now an ESM module and targets Node 24. Consumers pinning the action via commit SHA will need to re-pin; consumers using `@v3` or later will continue to work unchanged. Local development now requires Node 24+ (previously Node 20+). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Bump the `@actions/*` toolkit to the latest majors, all of which are now published as native ESM (see `actions/toolkit` release notes for each package): - `@actions/core`: `^1.11.1` → `^3.0.0` - `@actions/exec`: `^1.1.1` → `^3.0.0` - `@actions/glob`: `^0.5.0` → `^0.6.1` - `@actions/http-client`: `^2.2.3` → `^4.0.0` - `@actions/io`: `^1.1.3` → `^3.0.2` - `@actions/tool-cache`: `^2.0.2` → `^4.0.0` Because the upgraded packages are true ESM (rather than ESM-wrapped CJS), their named exports are now non-configurable and cannot be stubbed directly via `sinon.stub(ns)`. Add `src/actions.ts`, which re-exports each `@actions/*` package as a plain mutable object (typed back to the original module type). Both source code and tests now import from `src/actions.ts`, giving sinon a single shared object to stub while preserving the full upstream API surface. Update `.github/copilot-instructions.md` to describe the new wrapper module and refresh the guidance that was previously written for the CJS shape of the toolkit. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Migrate the action to native ESM on Node 24 so it can consume the ESM-only majors of the
@actions/*toolkit (and any future ESM-only dependencies) without a transpile-to-CJS step. This supersedes Dependabot PR tediousjs#206, which cannot be merged against the current CJS build.Changes
Two atomic commits:
1.
feat!: rewrite as an ESM moduleTooling:
"type": "module"; emit ESM throughout.@vercel/ncc→ Rollup (@rollup/plugin-typescript,-node-resolve,-commonjs,-json,-terser). Output is stilllib/main/index.jssoaction.ymlis unchanged.ts-node/tsx→ Node 24 native TypeScript type-stripping..tsfiles execute directly undernode; mocha runs with no TS loader.nyc+@istanbuljs/nyc-config-typescript→ c8..nycrc.jsonis retained as the config file (c8 reads it natively)..tsextensions throughout;tsconfig.jsonsetsallowImportingTsExtensions+rewriteRelativeImportExtensions.misc/generate-docs.tsESM-ified (JSON import attribute,import.meta.url).Source adjustments to keep sinon stubbing working: modules that expose runtime values now
export defaulta plain object alongside their named exports; call-sites useimport foo from './foo.ts'; foo.bar(). This is required because ES-module named-export bindings are read-only and cannot be rebound by sinon.2.
feat!: upgrade @actions/* toolkit to v3/v4 ESM majorsBumps matching Dependabot tediousjs#206:
@actions/core^1.11.1^3.0.0@actions/exec^1.1.1^3.0.0@actions/glob^0.5.0^0.6.1@actions/http-client^2.2.3^4.0.0@actions/io^1.1.3^3.0.2@actions/tool-cache^2.0.2^4.0.0Because these are now true ESM (rather than ESM-wrapped CJS), their named exports are non-configurable and cannot be stubbed directly. A new
src/actions.tswrapper re-exports each@actions/*package as a plain mutable object (typed back to the original module type). Both source and tests import from this wrapper so sinon has a single shared object to stub.Verification
npm run build— clean build via Rollup.npm test— 82 passing, 0 failing.npm run test:coverage— 99.48% statements / 98.81% branches / 100% functions / 100% lines.npm run lint— clean.BREAKING CHANGE
The action is now an ESM module and targets Node 24. Consumers using
@v3or later will continue to work unchanged at the action-invocation level, but this warrants a major version bump (hencefeat!). Local development now requires Node 24+ (previously Node 20+).Closes tediousjs#206.