wallaby-testing

name	wallaby-testing
description	Check test status and debug failing tests using Wallaby.js real-time test results. Use after making code changes to verify tests pass, when checking if tests are failing, debugging test errors, analyzing assertions, inspecting runtime values, checking coverage, updating snapshots, or when user mentions Wallaby, tests, coverage, or test status.
compatibility	Requires Wallaby.js VS Code extension installed and running
metadata	{"author":"wallaby.js","version":"1.0"}

Wallaby Testing Skill

Check test status and debug failing tests using Wallaby.js real-time test execution data.

When to Use

• After code changes - Verify tests pass after modifications
• Checking test status - See if any tests are failing
• Debugging failures - Analyze test errors and exceptions
• Inspecting runtime values - Examine variable states during tests
• Understanding coverage - See which code paths tests execute
• Updating snapshots - When snapshot changes are needed
• User mentions "tests", "test status", "run tests", or "Wallaby"

Available Wallaby Tools

Use these tools to gather test information:

Tool	Purpose
wallaby_failingTests	Get all failing tests with errors and stack traces
wallaby_failingTestsForFile	Get failing tests for a specific file
wallaby_allTests	Get all tests (useful when there are no failures but you need test IDs)
wallaby_allTestsForFile	Get tests covering/executing a specific file
wallaby_failingTestsForFileAndLine	Get failing tests covering/executing a specific file and line
wallaby_allTestsForFileAndLine	Get tests covering a specific line
wallaby_runtimeValues	Inspect variable values at a code location
wallaby_runtimeValuesByTest	Get runtime values for a specific test
wallaby_coveredLinesForFile	Get coverage data for a file
wallaby_coveredLinesForTest	Get lines covered by a specific test
wallaby_testById	Get detailed test data by ID
wallaby_updateTestSnapshots	Update snapshots for a test
wallaby_updateFileSnapshots	Update all snapshots in a file
wallaby_updateProjectSnapshots	Update all snapshots in the project

What Inputs These Tools Need

• For file-scoped tools (like wallaby_failingTestsForFile, wallaby_coveredLinesForFile): pass the workspace-relative file path.
• For line-scoped tools (like wallaby_allTestsForFileAndLine, wallaby_runtimeValues): pass file, line, and the exact lineContent string from the file.
• For test-scoped tools (like wallaby_testById, wallaby_runtimeValuesByTest, wallaby_coveredLinesForTest): pass testId from wallaby_failingTests / wallaby_allTests.

Debugging Workflow

Step 1: Get Failing Tests

Start by retrieving failing test information:

• Use wallaby_failingTests to see all failures
• Review error messages and stack traces
• Note the test ID for further inspection

If there are no failing tests but the user is asking about test status or coverage, use wallaby_allTests to confirm the current state and to obtain test IDs.

Step 2: Locate Related Code (Optional)

If the error and stack trace from Step 1 don't provide enough context:

• Use wallaby_coveredLinesForTest with the test ID
• Focus analysis on covered source files
• Identify which code paths are executed
• Skip this step if the failure cause is already clear

Step 3: Inspect Runtime Values (Optional)

Examine variable states at failure points or other points of interest:

• Use wallaby_runtimeValues for specific locations
• Use wallaby_runtimeValuesByTest for test-specific values
• Compare expected vs actual values
• Skip this step if the failure cause is already clear

Step 4: Implement Fix

Based on analysis:

• Identify the root cause
• Make targeted code changes
• Reference runtime values in your explanation

Step 5: Verify Fix

After changes:

• Wallaby re-runs tests automatically
• Use wallaby_testById to confirm test passes
• Check no regressions with wallaby_failingTests

Step 6: Update Snapshots (if needed)

When snapshots need updating:

• Use wallaby_updateTestSnapshots for specific tests
• Use wallaby_updateFileSnapshots for all in a file
• Use wallaby_updateProjectSnapshots only when many snapshots changed
• Verify tests pass after updates

Example: Debugging an Assertion Failure

User: "The calculator test is failing"

1. Call wallaby_failingTests → Get test ID and error Error shows: "expected 4, got 5" in multiply function
2. (Optional) Call wallaby_coveredLinesForTest(testId) → Skip if error is clear
3. (Optional) Call wallaby_runtimeValues(file, line, expression) → Skip if cause is obvious
4. Analyze: multiply used + instead of *
5. Fix: Change + to * in calculator.js
6. Call wallaby_failingTests → Confirm no failures remain

Best Practices

• Use Wallaby tools first - They provide real-time data without re-running tests
• Get test IDs early - Many tools require the test ID from initial queries
• Inspect runtime values - More reliable than guessing variable states
• Verify after fixes - Always confirm the test passes before finishing
• Check for regressions - Ensure fixes don't break other tests