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Phase 5 Plan 4: Cross-Generator Consistency Tests Summary

Nullable and empty_behavior cross-generator consistency validated: byte-identical Go JSON, TypeScript T | null types, OpenAPI 3.1 type arrays and oneOf schemas

Performance#

  • Duration: 4 min
  • Started: 2026-02-06T10:16:48Z
  • Completed: 2026-02-06T10:21:00Z
  • Tasks: 3/3
  • Files modified: 6

Accomplishments#

  • Validated go-http and go-client produce byte-identical nullable JSON encoding (after generator name normalization)
  • Validated go-http and go-client produce byte-identical empty_behavior JSON encoding
  • Verified TypeScript correctly uses T | null for nullable fields (not optional ?)
  • Verified OpenAPI correctly uses type array [T, "null"] for nullable and oneOf for empty_behavior=NULL
  • Added empty_behavior test proto and golden files to clientgen (was missing from 05-03)
  • Zero regressions across all 4 generators

Task Commits#

Each task was committed atomically:

  1. Task 1: Nullable cross-generator consistency tests - 47a9867 (test)
  2. Task 2: Empty behavior cross-generator consistency tests - ff65053 (test)
  3. Task 3: Full test suite verification - (verification only, no commit)

Files Created/Modified#

  • internal/httpgen/nullable_consistency_test.go - 4 test functions: GoHTTPvsGoClient, TypeScript, OpenAPI, BackwardCompat
  • internal/httpgen/empty_behavior_consistency_test.go - 3 test functions: GoHTTPvsGoClient, OpenAPI, BackwardCompat
  • internal/clientgen/testdata/proto/empty_behavior.proto - Test proto for clientgen empty_behavior golden generation
  • internal/clientgen/testdata/golden/empty_behavior_client.pb.go - Clientgen empty_behavior client golden file
  • internal/clientgen/testdata/golden/empty_behavior_empty_behavior.pb.go - Clientgen empty_behavior encoding golden file
  • internal/clientgen/golden_test.go - Added empty_behavior test case

Decisions Made#

  • D-05-04-01: Added empty_behavior.proto and golden files to clientgen testdata as a Rule 3 deviation. The 05-03 plan created the empty_behavior.go generator code in clientgen but not the test proto/golden files, which blocked byte-level golden file comparison. Identical proto file used (same pattern as nullable).

Deviations from Plan#

Auto-fixed Issues#

1. [Rule 3 - Blocking] Added empty_behavior test proto and golden files to clientgen

  • Found during: Task 1 (preparing for empty_behavior consistency test)
  • Issue: clientgen had empty_behavior.go (generator code) but no test proto or golden files, making byte-level output comparison impossible
  • Fix: Copied empty_behavior.proto from httpgen testdata, added test case to clientgen golden_test.go, generated golden files with UPDATE_GOLDEN=1
  • Files modified: internal/clientgen/testdata/proto/empty_behavior.proto, internal/clientgen/golden_test.go, internal/clientgen/testdata/golden/empty_behavior_client.pb.go, internal/clientgen/testdata/golden/empty_behavior_empty_behavior.pb.go
  • Verification: All clientgen golden tests pass including new empty_behavior case
  • Committed in: 47a9867 (Task 1 commit)

Total deviations: 1 auto-fixed (1 blocking) Impact on plan: Essential for complete cross-generator consistency testing. No scope creep.

Issues Encountered#

None.

User Setup Required#

None - no external service configuration required.

Next Phase Readiness#

  • Cross-generator consistency fully validated for nullable and empty_behavior
  • Ready for plan 05-05 (integration tests or phase completion)
  • All existing tests continue to pass (zero regression)

Phase: 05-json-nullable-empty Completed: 2026-02-06