feat(cli): add test coverage reporting with Bun

Enable V8-based code coverage for CLI tests:
- Configure coverage in bunfig.toml (text + lcov reporters)
- Add test:fast and test:coverage npm scripts
- Update GitLab CI to capture coverage percentage and artifacts
- Add coverage/ to .gitignore

Coverage reports are now visible in GitLab MR pipelines.
Closes #74 (CLI part)

Author: claude

.gitlab-ci.yml

@@ -218,7 +218,16 @@ cli:node:tests:
     - su - pgtest -c "cd \"$CI_PROJECT_DIR/cli\" && export PATH=\"\$HOME/.bun/bin:\$PATH\" && bun install"
   script:
     # Use 'bun run test' (not 'bun test') to invoke the npm script which generates metrics-embedded.ts first
+    # Coverage is enabled via bunfig.toml and outputs text + lcov reports
     - su - pgtest -c "cd \"$CI_PROJECT_DIR/cli\" && export PATH=\"\$HOME/.bun/bin:\$PATH\" && bun run test"
+    # Fix ownership of coverage directory for artifact collection
+    - chown -R root:root "$CI_PROJECT_DIR/cli/coverage" || true
+  coverage: '/All files[^|]*\|[^|]*\|[^|]*\|[^|]*\|\s*([\d.]+)/'
+  artifacts:
+    when: always
+    paths:
+      - cli/coverage/
+    expire_in: 7 days
   rules:
     - if: '$CI_PIPELINE_SOURCE == "merge_request_event"'
 

cli/.gitignore

@@ -1 +1,4 @@
 package-lock.json
+node_modules/
+dist/
+coverage/

cli/bunfig.toml

@@ -6,6 +6,15 @@
 # Integration tests that connect to databases need longer timeouts
 timeout = 30000
 
-# Coverage settings (if needed in future)
-# coverage = true
-# coverageDir = "coverage"
+# Coverage settings - enabled by default for test runs
+# Uses V8's built-in coverage engine
+coverage = true
+coverageDir = "coverage"
+
+# Skip coverage for test files and node_modules
+coverageSkipTestFiles = true
+
+# Reporter format for CI integration
+# - text: console output with summary table
+# - lcov: standard format for coverage tools
+coverageReporter = ["text", "lcov"]

cli/package.json

@@ -32,6 +32,8 @@
     "start:node": "node ./dist/bin/postgres-ai.js --help",
     "dev": "bun run embed-metrics && bun --watch ./bin/postgres-ai.ts",
     "test": "bun run embed-metrics && bun test",
+    "test:fast": "bun run embed-metrics && bun test --coverage=false",
+    "test:coverage": "bun run embed-metrics && bun test --coverage && echo 'Coverage report: cli/coverage/lcov-report/index.html'",
     "typecheck": "bun run embed-metrics && bunx tsc --noEmit"
   },
   "dependencies": {