refactor(mapper): rename methods from ToItem/FromItem to FromModel/ToModel

[j-d-ha]

🚀 Pull Request

📋 Summary

This PR implements a comprehensive refactoring to change the naming convention for mapper methods from FromItem/ToItem to FromModel/ToModel with semantic reversal:

• ToItem → FromModel (Model → DynamoDB mapping)
• FromItem → ToModel (DynamoDB → Model mapping)
• Hook names also reversed: BeforeToItem → BeforeFromModel, AfterToItem → AfterFromModel, etc.

This makes the API more intuitive by naming methods based on their relationship TO or FROM the model (domain object), rather than the DynamoDB item representation.

---

🔧 Changes Made

Phase 1: Generator & Runtime Code (12 files)

• Updated all core generator files:
  • MapperClassInfo.cs - Swapped method detection logic and renamed properties
  • GeneratorContext.cs - Renamed context flags (HasFromModelMethod, HasToModelMethod)
  • PropertyMappingSpecBuilder.cs - Renamed all builder methods
  • PropertyMappingCodeRenderer.cs - Updated rendering methods
  • Mapper.scriban - Updated template variables
  • MapperEmitter.cs - Updated data passed to template
  • TypeMappingStrategyResolver.cs - Updated context flag references
• Updated runtime IgnoreMapping.cs XML documentation

Phase 2: Test Files (25 files)

• Updated 3 test class files with new method names
• Updated all 22 verified snapshot files
• Fixed property names in DynamoIgnoreVerifyTests (IgnoreInFromModel/IgnoreInToModel)

Phase 3: Example Projects (5 files)

• Updated DynamoMapper.SimpleExample/Program.cs
• Updated DynamoMapper.FieldLevelOverride/Program.cs
• Fixed 3 temp files

Phase 4: Documentation (12 files)

• Updated README.md, CLAUDE.md
• Updated all files in docs/:
  • getting-started/, core-concepts/, usage/, examples/, roadmap/
• Updated hook names throughout documentation
• Updated dynamo-field-attribute-checklist.md

---

✅ Checklist

• My changes build cleanly
• I've added/updated relevant tests (all 22 generator tests passing)
• I've added/updated documentation or README
• I've followed the coding style for this project
• I've tested the changes locally (all tests passing)

---

🧪 Test Results

• ✅ Build succeeded with 0 errors (3 warnings in temp files)
• ✅ All 22 generator tests passing
• ✅ All 192 runtime tests passing

---

💬 Notes for Reviewers

Breaking Change

This is a MAJOR breaking change:

• All existing mapper classes must update method names from ToItem/FromItem to FromModel/ToModel
• Hook method names must be updated if used
• Generated code structure changes completely

Key Design Decision

The refactoring uses semantic reversal rather than simple renaming:

• Methods starting with "To" prefix (e.g., ToModel) now map DynamoDB → Model
• Methods starting with "From" prefix (e.g., FromModel) now map Model → DynamoDB
• The method prefix constants (ToMethodPrefix = "To", FromMethodPrefix = "From") remain unchanged, but their semantic interpretation is reversed

This aligns the naming with the model-centric design philosophy where methods are described relative to the model, not the item representation.

Files Changed

51 files changed, 507 insertions(+), 487 deletions(-)

Recommendation

Consider bumping version to 0.2.0-alpha or 1.0.0 to reflect the breaking change.

[ncipollina]

✅ LGTM