diagnose

# Diagnose Test Failure ## Overview Systematic diagnosis of test failures in the Morphia project. Run the test, read the full error, trace the root cause through source and generated code, fix minimally, and verify. ## Workflow 1. **Run the failing test** ``` ./mvnw test -pl :module-name -Dtest="ClassName#methodName" -Ddeploy.skip=true ``` - Use `-Ddeploy.skip=true` to skip dokka - Do NOT use `-am` with `-Dtest=` (applies test filter to all modules) - If dependencies need rebuilding first: ``` ./mvnw install -pl :dep1,:dep2 -DskipTests -Ddeploy.skip=true -Dinvoker.skip=true ``` 2. **Read the full error** - stack trace, error message, line numbers. Don't skip anything. 3. **Find relevant code** - Read both source AND generated code: - Source: `src/main/`, `src/test/` - Generated bytecode: `target/test-classes/` - use `javap -c -p ClassName` to decompile - Generated sources: `target/generated-sources/` - Interfaces from dependencies: check `~/.m2/repository/` source jars with `unzip -p` 4. **Trace the root cause** - Follow the error backward: - What method is missing/wrong? - What generated it? (Gizmo generator? ASM generator?) - What does the interface/superclass require? - Compare with working examples (ASM-based generators have bridge methods; check if Gizmo-based ones do too) 5. **Fix minimally** - One change at a time. Rebuild affected modules: ``` ./mvnw install -pl :critter-core,:critter-maven -DskipTests -Ddeploy.skip=true -Dinvoker.skip=true ``` 6. **Verify** - Re-run the failing test AND related tests in the same class. ## Common Morphia/Critter Issues | Error | Likely Cause | |-------|-------------| | `AbstractMethodError` | Missing bridge methods in generated bytecode (generic interface erasure) | | `Cannot checkcast to primitive` | Gizmo `checkCast` doesn't work on primitives - use `smartCast` | | `Cannot convert primitive to Object` | Need boxing: `smartCast(result, wrapperType)` | | `NoSuchMethodError __read*/__write*` | Accessor methods not generated on entity class | | `ClassNotFoundException __morphia.*` | Critter code generation didn't run or class not registered | ## Key Gotchas - Gizmo does NOT auto-generate bridge methods for generic interfaces - Primitive types need explicit boxing/unboxing via `smartCast` - `checkCast(Object -> wrapper)` then `smartCast(wrapper -> primitive)` for unboxing - `smartCast(primitive -> wrapper)` for boxing - Always check both Gizmo (`parser/gizmo/`) and ASM (`parser/asm/`) generators for patterns