divine-mobile: Skill for Claude Code

Mockito Stale Mock + Silent Try/Catch Test Failures

Problem

When a PR adds new methods to a service class (e.g., AnalyticsApiService), and those methods are called from existing code paths that are wrapped in try/catch blocks, tests fail with misleading symptoms. The test assertion shows Expected: non-empty, Actual: [] or Expected: true, Actual: false — but the actual root cause is a MissingStubError being silently caught.

Context / Trigger Conditions

• Symptom: Test expects data (non-empty list, specific values) but gets empty/default
• No obvious error: No MissingStubError in test output because production code catches it
• PR context: The PR added new methods to a @GenerateMocks-annotated service class
• CI also shows: "Generated files are out of date" (stale .g.dart / .mocks.dart)
• Existing tests were passing before the PR's changes

The Failure Chain

1. PR adds method `getBulkVideoViews()` to AnalyticsApiService
2. PR adds `_enrichVideosWithBulkStats()` to HomeFeedProvider.build()
3. _enrichVideosWithBulkStats calls getBulkVideoViews (new method)
4. Generated mock is stale — doesn't have getBulkVideoViews at all
5. Even if regenerated, test setUp doesn't stub getBulkVideoViews
6. Mock throws MissingStubError when unstubbed method is called
7. Provider's try/catch catches ALL exceptions (including MissingStubError)
8. Provider falls back to empty state → test sees [] instead of expected data

Solution

Step 1: Regenerate mocks

dart run build_runner build --delete-conflicting-outputs

This updates all .g.dart and .mocks.dart files to include new methods.

Step 2: Identify new method calls in modified code paths

Trace the code path from the test's entry point. Look for any method calls on mocked services that were added or modified by the PR. Pay special attention to methods called after the already-stubbed method (e.g., enrichment/post-processing steps).

Step 3: Add stubs for ALL methods in the call chain