test: Adding unit test coverage and continuous integration pipeline.

.github/workflows/ci.yml

@@ -0,0 +1,40 @@
+name: CI
+
+on:
+  pull_request:
+    types: [opened, synchronize, reopened]
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ci-${{ github.event.pull_request.number }}
+  cancel-in-progress: true
+
+jobs:
+  build_and_test:
+    name: Build and Test
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: FASTBuildMonitorVSCode
+    steps:
+      - uses: actions/checkout@v6
+      - uses: actions/setup-node@v6
+        with:
+          node-version: 24
+          cache: npm
+          cache-dependency-path: |
+            FASTBuildMonitorVSCode/package-lock.json
+            FASTBuildMonitorVSCode/webview-ui/package-lock.json
+      - run: npm run ci:all
+      - run: npm run build:all
+      - run: npm run test:typecheck
+      - run: npm run test:coverage
+      - name: Upload coverage report
+        if: always()
+        uses: actions/upload-artifact@v7
+        with:
+          name: coverage
+          path: FASTBuildMonitorVSCode/coverage
+          if-no-files-found: ignore

FASTBuildMonitorVSCode/.gitignore

@@ -3,4 +3,4 @@ node_modules/
 .vscode-test/
 *.vsix
 artifacts/
-
+coverage/

FASTBuildMonitorVSCode/.vscodeignore

@@ -4,6 +4,8 @@
 
 artifacts/**
 scripts/**
+tests/**
+coverage/**
 src/**
 **/.gitignore
 .yarnrc
@@ -14,10 +16,13 @@ src/**
 **/*.ts
 
 webview-ui/src/**
+webview-ui/tests/**
 webview-ui/node_modules/**
 
 node_modules/**
 
 # Config files
 esbuild.js
-*.config.js
+*.config.js
+vitest.config.mts
+tsconfig.test.json

FASTBuildMonitorVSCode/CONTRIBUTING.md

@@ -1,3 +1,15 @@
+## Development and tests
+
+From `FASTBuildMonitorVSCode`, using Node.js 24:
+
+```bash
+npm run ci:all
+npm test
+npm run test:coverage
+```
+
+Vitest covers the extension core and React web UI. Pull requests automatically build both parts, type-check tests, and validate coverage. 
+
 # Release Process
 This repository uses [semantic-release](https://github.com/semantic-release/semantic-release) for it's releases.  That means that any commit that goes into `mojang/main` will potentially trigger a release and contribute to the changelog.
 
@@ -15,17 +27,53 @@ Some examples of this are:
 
 # Local Development
 
-Initialize
+Use Node.js 24. Run the following commands from `FASTBuildMonitorVSCode`.
+
+Install the extension and webview dependencies from the committed lockfiles:
 ```bash
-npm install:all
+npm run ci:all
 ```
 
-Build
+When changing dependencies, use `npm run install:all` and commit both updated lockfiles.
+
+Build:
 ```bash
 npm run build:all
 ```
 
-To test: press F5 in VS Code to launch the Extension Development Host.
+## Automated tests
+
+The project uses [Vitest](https://vitest.dev/) with two projects:
+
+- `extension`: Node-based tests in `tests/extension` covering log polling and parsing, build sessions and workers, configuration and utilities, activation, commands, status updates, and webview messaging.
+- `webview`: React Testing Library tests in `webview-ui/tests`, running in jsdom, covering snapshot updates, controls, statistics, job lists, themes, progress contrast, and timeline rendering, core allocation, scrolling, zooming, and tooltips.
+
+Run both suites once:
+
+```bash
+npm test
+```
+
+Run a single project or use watch mode:
+
+```bash
+npm test -- --project extension
+npm test -- --project webview
+npm test -- --watch
+```
+
+Type-check the tests and collect coverage:
+
+```bash
+npm run test:typecheck
+npm run test:coverage
+```
+
+Coverage includes all extension and webview TypeScript sources, including files not imported by a test. Declaration files are excluded. Every source file must meet at least **80% statements, lines, and functions**, and **75% branches**. Reports are written to `coverage`; open `coverage/index.html` for the detailed report. Add behavior-focused regression tests alongside changes rather than excluding uncovered production code.
+
+The extension tests mock the VS Code API and file polling boundaries, and use fake timers instead of real polling delays. Webview tests mock the VS Code bridge, canvas operations/pixel samples, and resize observers. They do not require VS Code, a running FASTBuild process, or a browser. These tests do not replace visual checks of actual canvas rendering: press F5 in VS Code to launch the Extension Development Host for manual validation.
+
+The [CI workflow](../.github/workflows/ci.yml) runs on pull requests when opened, updated, or reopened. It installs locked dependencies, builds both parts, type-checks tests, enforces coverage thresholds, and uploads the coverage report. It uses read-only repository permissions and does not require release credentials. To enforce it before merging, configure the **Build and Test** check as required in branch protection.
 
 # Architecture
 

FASTBuildMonitorVSCode/README.md

@@ -51,3 +51,4 @@
 | `fbuildmonitor.logPath`      | `""`    | Custom path to `FastBuildLog.log`. Empty = auto-detect from `%TEMP%\FASTBuild\` or `FASTBUILD_TEMP_PATH`. |
 | `fbuildmonitor.pollInterval` | `500`   | Log file poll interval in milliseconds (100–5000).                                                        |
 | `fbuildmonitor.autoStart`    | `true`  | Auto-start monitoring when the panel opens.                                                               |
+| `fbuildMonitor.useLegacyColors` | `false` | Use the original fixed dark color scheme instead of colors derived from the active VS Code theme. |