This will add a @ocap/test-utils/endoified helper that would make it possible to write tests that would be evaluated after @ocap/shims/endoify.

To get this working, I've made other changes that are secondary to the intent of this PR. Those changes are just for staging purposes and will be reverted once the relevant PRs land.

The approach used for testing is to first evaluate the bundled @ocap/shims/endoify source text inside a pristine JSDOM instance, which is then followed by evaluating the function body of the test itself passing to it an endowments object with the respective vitest capabilities as its only argument.

Simplified code for the endoified helper:

type VitestCapabilities = typeof import('vitest');

function endoified<Endowments extends Partial<VitestCapabilities>(
  test: (endowments: Endowments) => void,
  endowments: Endowments,
) {
  return () => {
    const evaluatorSourceText = String(test);
    const endoifySourceText = readFileSync(relativeEndoifySourcePath, 'utf-8');
    const dom = new jsdom.JSDOM('');
  
    dom.window.eval(endoifySourceText);
    (dom.window.eval(evaluatorSourceText) as typeof test)(endowments);
  };
}

Considerations

Enhancements

• The endoified helper may need to use a different endoify bundle.

  • This would support the experimental testing efforts.

• The endoified helper JSDOM context may need to be reused.

  • This would support the experimental testing efforts.

Requirements

• The endoified helper may need to support the use of JS modules.

  • This would address a limitation with JSDOM that can be addressed using NODE_OPTIONS=--experimental-vm-modules along with linkage logic for vm.SourceTextModule.

• The endoified helper maybe need to bundle the shims/dist/endoify.m?js on-demand.

  • This would address a limitation with the current test workflow:

    ocap-kernel/.github/workflows/lint-build-test.yml

    Lines 125 to 154 in c9cb406

    	test:
    	name: Test
    	runs-on: ubuntu-latest
    	needs: prepare
    	strategy:
    	matrix:
    	node-version: [18.x, 20.x]
    	package-name: ${{ fromJson(needs.prepare.outputs.child-workspace-package-names) }}
    	steps:
    	- uses: actions/checkout@v4
    	- name: Install Node.js ${{ matrix.node-version }}
    	uses: actions/setup-node@v4
    	with:
    	node-version: ${{ matrix.node-version }}
    	- name: Install Yarn
    	run: corepack enable
    	- name: Restore Yarn cache
    	uses: actions/setup-node@v4
    	with:
    	node-version: ${{ matrix.node-version }}
    	cache: yarn
    	- run: yarn --immutable
    	- run: yarn workspace ${{ matrix.package-name }} run test
    	- name: Require clean working directory
    	shell: bash
    	run: |
    	if ! git diff --exit-code; then
    	echo "Working tree dirty at end of job"
    	exit 1
    	fi

Alternatives

• Custom Environment as an alternative — thanks @grypez
• Browser Mode as an alternative — thanks @rekmarks
  test(extension,streams): Set up browser tests #12 — thanks @grypez

Issues

• Inconsistencies in the behaviour of import.meta between JS modules directly in node and ts files via vitest.
• Support for JS modules with
  JSDOM requires the

Threads

• shims: Bundle eventual-send using @endo/bundle-source #10
  • build(shims): Bundle eventual-send using @endo/bundle-source #22