Create claude.md

Author: SimonCropp

claude.md

@@ -0,0 +1,81 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+Verify.EntityFramework extends the [Verify](https://github.com/VerifyTests/Verify) snapshot testing framework to support Entity Framework testing. It provides utilities for snapshot testing EF operations including change tracking, query execution, and SQL recording.
+
+The repository contains two main packages:
+- **Verify.EntityFramework** - For EF Core (modern)
+- **Verify.EntityFrameworkClassic** - For EF 6 (legacy)
+
+## Build Commands
+
+```bash
+# Build the solution
+dotnet build src
+
+# Run tests (excludes integration tests by default)
+dotnet test src
+
+# Run a specific test
+dotnet test src --filter "FullyQualifiedName~CoreTests.Added"
+
+# Run tests in a specific project
+dotnet test src/Verify.EntityFramework.Tests
+```
+
+## Project Structure
+
+```
+src/
+├── Verify.EntityFramework/           # EF Core library
+│   ├── VerifyEntityFramework.cs      # Main public API
+│   ├── Converters/                   # JSON converters for EF objects
+│   │   ├── QueryableConverter.cs     # Converts IQueryable to SQL + results
+│   │   ├── TrackerConverter.cs       # Converts ChangeTracker state
+│   │   └── LogEntryConverter.cs      # Recorded SQL entries
+│   ├── LogCommandInterceptor.cs      # DbCommandInterceptor for SQL recording
+│   └── MissingOrder/                 # Detects missing ORDER BY clauses
+│
+├── Verify.EntityFramework.Tests/     # EF Core tests
+├── Verify.EntityFrameworkClassic/    # EF 6 library
+└── Verify.EntityFrameworkClassic.Tests/
+```
+
+## Architecture
+
+### Module Initialization Pattern
+Tests use `[ModuleInitializer]` to call `VerifyEntityFramework.Initialize(model)` once at assembly load, passing an `IModel` from a DbContext. This caches navigation property information for later use.
+
+### Key Extension Points
+
+1. **Converters** - Custom JSON converters inherit from `WriteOnlyJsonConverter<T>` and are registered globally via `VerifierSettings.RegisterFileConverter()` or added to `DefaultContractResolver.Converters`.
+
+2. **Recording System** - `LogCommandInterceptor` implements `DbCommandInterceptor` to capture SQL operations. Enable via `builder.EnableRecording()` on `DbContextOptionsBuilder`.
+
+3. **Queryable Verification** - When verifying an `IQueryable`, generates both a `.txt` file (query results) and a `.sql` file (the SQL query).
+
+### Main API Methods (VerifyEntityFramework.cs)
+
+- `Initialize(IModel)` - Required setup, caches model metadata
+- `AllData()` - DbContext extension to enumerate all database entities
+- `IgnoreNavigationProperties()` - Exclude EF navigation properties from serialization
+- `EnableRecording()` - Enable SQL command recording on DbContextOptionsBuilder
+- `DisableRecording()` - Stop recording for a specific context instance
+- `ThrowForMissingOrderBy()` - Enforce ORDER BY clauses in queries
+- `ScrubInlineEfDateTimes()` - Sanitize DateTime values in SQL
+
+## Testing Conventions
+
+- Uses NUnit with `[Parallelizable(ParallelScope.All)]`
+- Snapshot files follow pattern: `TestClass.TestMethod.verified.txt`
+- Async tests use `await Verify(...)` pattern
+- Tests create in-memory SQLite databases or use SQL Server LocalDB
+
+## Dependencies
+
+- .NET 10.0 SDK (preview features enabled)
+- C# language version: preview
+- Key packages: Verify, Microsoft.EntityFrameworkCore, NUnit