extension-test-patterns

name	extension-test-patterns
description	Chooses between Jest unit tests and @vscode/test-electron extension-host tests for Agent Skill Sync. Use when adding tests for services, webview components, or extension activation/webview integration.
disable-model-invocation	true

Extension test patterns

Two runners

Runner	Entry	Use for
Jest	npm test / task test	Services, utilities, React components (jsdom)
@vscode/test-electron	npm run test:extension / task test-extension	Real Extension Host: activation, commands, webviews

Jest configuration

jest.config.js:

• vscode mock: "^vscode$": "<rootDir>/src/test/vscodeMock.ts" — extension code importing vscode gets the mock automatically.
• CSS mock: maps to src/test/styleMock.ts.
• src/test/suite/ excluded — those files are Mocha suites for the extension host, not Jest.

Setup: src/test/setupTests.ts pulls in @testing-library/jest-dom.

Extension-host runner

src/test/runExtensionTests.ts resolves the repo root and loads src/test/suite/index. Use this path when debugging “tests pass in Jest but fail in real VS Code.”

When to extend vscodeMock

Prefer updating src/test/vscodeMock.ts when multiple tests need the same API surface (e.g. new workspace.fs behavior). Keeps mocks consistent and avoids duplicated jest.mock blocks.

Quick checklist for new code

• Pure logic / axios / parsers → Jest file next to source or under src/test/*.test.ts.
• React presentational / hooks with injected API → Jest + Testing Library in webview-ui/*.test.tsx.
• End-to-end extension behavior → src/test/suite/.

Commands

task test              # or npm test
task test-extension    # or npm run test:extension
task check             # full gate before release