Loft Sh Vcluster Vcluster

E2E Test Migration Validator

A skill for exhaustively reviewing e2e tests migrated from the old framework (next/ directory) to the new framework (e2e/ directory) across the vcluster, vcluster-pro, and loft-enterprise repositories.

Inputs

The user will provide one or more of:

• Uploaded file(s): The new migrated test file, and optionally the original test file
• GitHub PR link: A pull request URL containing the migrated test(s)
• Pasted code: Snippets of old and/or new test code inline in the chat

If only the new test is provided (no original), you must locate the original yourself using the local repo tools (see Repo Access).

Repo Access

Use the local repo MCP tools to inspect implementation details and locate source files. All three repos may be relevant depending on the test subject:

When reviewing a test, always look up the actual implementation being tested in the relevant repo before drawing conclusions about correctness or coverage. Do not rely solely on what the test itself asserts.

Review Workflow

Follow these steps in order for every migration review:

Step 1 — Locate the Original Test

If the original (next/) test was not provided:

1. Search the appropriate repo(s) for the original test file by name or describe pattern
2. Read it fully before proceeding
3. Note the framework, helper utilities, and assertion style used

Step 2 — Locate the Implementation Under Test

Using the repo MCP tools:

1. Find the source code that the test is exercising (controllers, handlers, CLI commands, API routes, UI components, etc.)
2. Read the implementation thoroughly — line by line if needed
3. Build a mental model of:
   • All code paths (happy path, error paths, edge cases)
   • All configurable inputs / flags / options
   • Side effects and state mutations
   • Interactions with other subsystems

Step 3 — Framework Migration Check

Verify the structural correctness of the migration:

• Test file is in the correct e2e/ directory structure
• Imports use the new framework's helpers/fixtures (not the old ones)
• Test lifecycle hooks (beforeAll, afterAll, beforeEach, afterEach) are correctly translated — no leftover old-framework teardown patterns
• Setup and teardown create/delete resources correctly and completely
• Cluster/namespace/resource provisioning uses the new framework's APIs
• Any shared utilities (custom matchers, wait helpers, retry logic) are migrated or replaced with new equivalents — not just copied verbatim
• Test isolation is maintained (tests do not share mutable state across runs)
• Framework-specific APIs (e.g. page, context, request) are used correctly

Step 4 — Correctness Check

For each test case in the migrated file:

1. Does the test actually test what it claims to test?
   • Read the test name / description and compare against what is asserted
   • Flag any tests where the name and assertions are misaligned
2. Are the assertions meaningful?
   • Look for trivially-passing assertions (e.g. expect(x).toBeDefined() with no deeper check)
   • Look for assertions that would pass even if the feature is broken
   • Look for missing negative assertions (e.g. testing that a resource was created but not that an invalid input was rejected)
3. Is the test deterministic?
   • Flag race conditions, missing await, missing retries on flaky operations
   • Flag hardcoded timeouts that may not hold in CI
4. Is the test environment realistic?
   • Does the test reflect how the feature is actually used in production?
   • Are there unrealistic shortcuts (e.g. bypassing auth, using superuser where a normal user should be tested)?

Step 5 — Exhaustive Coverage Analysis

This is the most important step. Compare the implementation (Step 2) against the test suite.

For every distinct behavior, code path, and configurable option in the implementation:

1. Check whether it is covered by at least one test
2. If not covered, classify the gap:
   • 🔴 Critical gap — a regression here would not be caught at all
   • 🟡 Important gap — partial coverage, but a significant edge case is missed
   • 🟢 Minor gap — low-risk or already covered by unit tests

For each gap, suggest a concrete additional test case including:

• What scenario it covers
• What inputs/state are needed
• What assertion(s) should be made

Common gap categories to check explicitly:

• Error handling and invalid inputs
• Permission / RBAC boundary conditions
• Resource limit enforcement
• Concurrent operations
• Feature flags / configuration variants
• Upgrade/downgrade paths (if applicable)
• Interaction with other features (cross-feature integration)
• Cleanup/teardown correctness (does the feature leave no orphaned resources?)

Step 6 — Code Quality Review

• Naming: are test and variable names descriptive and consistent with the new framework's conventions?
• DRY: is there duplicated setup that should be extracted into a shared fixture or helper?
• Readability: would a new engineer understand what is being tested and why?
• Comments: are non-obvious steps explained?
• Dead code: are there commented-out blocks, unused imports, or leftover debug statements?

Output Format

Produce all three of the following output sections:

1. Inline Code Analysis

Go through the migrated test file and annotate specific lines or blocks with numbered comments. Format as a fenced code block with inline // [N] ... annotations, followed by a numbered legend below it explaining each annotation.

Example:

// [1] Missing: should also assert that the old resource was deleted
await expect(newResource).toBeVisible();

// [2] Race condition: no retry/wait before asserting pod readiness
expect(pod.status).toBe('Running');

Legend:

1. 🔴 Critical gap — deletion is not verified; the old resource could persist undetected
2. 🟡 Flakiness risk — pod status may not be Running immediately; use waitForCondition

2. Checklist Report

## Migration Checklist — <test file name>

### Framework Migration
- [x] Correct directory structure
- [x] New framework imports
- [ ] ⚠️  Teardown uses old-framework pattern on line 42

### Correctness
- [x] Assertions are meaningful
- [ ] ⚠️  Test "should reject invalid config" passes even with valid config (line 87)

### Coverage Gaps
- 🔴 No test for RBAC: non-admin user attempting privileged operation
- 🟡 No test for concurrent resource creation
- 🟢 No test for audit log output (low risk)

### Code Quality
- [ ] ⚠️  Duplicate setup block (lines 12–25 and 61–74) — extract to beforeEach
- [x] Naming is clear and consistent

3. PR Review Comment

A copy-paste-ready GitHub PR review comment in Markdown. Structure:

## E2E Migration Review

**Overall:** ✅ Approved with suggestions / ⚠️ Changes requested / ❌ Major issues found

### Summary
<2–3 sentence high-level assessment>

### Issues

#### 🔴 Must Fix
- ...

#### 🟡 Should Fix
- ...

#### 🟢 Nice to Have
- ...

### Suggested Additional Tests
- **Test:** `<descriptive test name>`
  **Scenario:** <what to set up>
  **Assert:** <what to check>

<repeat for each suggested test>

### Nits
- ...

Framework Notes

For the reviewer using this skill: If you know the specific old and new frameworks involved in this migration, add them here so Claude can apply framework-specific checks.

Example entries:

• Old: @vcluster/e2e custom test runner → New: Playwright + @vcluster/e2e-next fixtures
• Old: Ginkgo/Gomega (Go) → New: Playwright (TypeScript)
• Old: Custom shell-script harness → New: Playwright with kubectl helpers

Until this section is filled in, Claude will infer the frameworks from the provided files.

Tips for High-Quality Reviews

• Always read the implementation first. A test that looks complete may miss half the code paths if you haven't read the source.
• Think adversarially. For each assertion, ask: "How could this pass even if the feature is broken?"
• Don't skip cleanup verification. Many e2e bugs are leaked resources, not failed assertions.
• Flag flakiness proactively. A flaky test is worse than no test — it erodes trust in the suite.
• Be specific in suggestions. Don't say "add more tests." Say exactly what scenario, what inputs, and what assertion.

Source: loft-sh/vcluster — distributed by TomeVault.