# Mock Flag Update

## Summary

Updated the `--mocks` flag to accept an explicit output path, improving usability and integration with build systems.

## Changes Made

### 1. Flag Syntax Change
**Before:**
```bash
zig build run -- header.h --output=bindings.zig --mocks
# Automatically created: header_mock.c
```

**After:**
```bash
zig build run -- header.h --output=bindings.zig --mocks=mocks.c
# Explicitly creates: mocks.c
```

### 2. Benefits
- **Explicit control**: Users specify exactly where mock file goes
- **Build system friendly**: Easy to integrate with Zig build system
- **Cleaner**: No automatic filename generation logic
- **Flexible**: Can output mocks anywhere in the project structure

### 3. Build Target Added
New `test-mocks` target for quick testing:
```bash
zig build test-mocks
# Generates: zig-out/test_small.zig and zig-out/test_small_mock.c
```

### 4. Files Modified

**build.zig**:
- Added `test-mocks` build step
- Outputs to `zig-out/` directory by default
- Uses absolute paths for consistency

**parser.zig**:
- Changed from `--mocks` (boolean flag) to `--mocks=<path>` (value flag)
- Removed automatic filename generation
- Updated usage documentation

**docs/usage.md**:
- Updated with new flag syntax
- Added command line options reference
- Added `test-mocks` target documentation

**PHASE1_COMPLETE.md**:
- Updated examples with new syntax
- Documented build system integration

## Examples

### Simple test:
```bash
zig build test-mocks
```

### Custom paths:
```bash
zig build run -- SDL_gpu.h --output=gen/bindings.zig --mocks=gen/mocks.c
```

### Just bindings (no mocks):
```bash
zig build run -- header.h --output=bindings.zig
```

## Backward Compatibility

**Breaking change**: The old `--mocks` flag (without a value) no longer works.

**Migration**:
```bash
# Old (no longer works)
zig build run -- header.h --output=out.zig --mocks

# New (required)
zig build run -- header.h --output=out.zig --mocks=header_mock.c
```

## Testing

All existing tests pass:
- ✅ 7 mock generation unit tests
- ✅ Parser tests
- ✅ Integration with test_small.h
- ✅ Integration with SDL_gpu.h (169 declarations)
- ✅ New `test-mocks` build target

## Implementation Time

- **Estimated**: 30 minutes
- **Actual**: 25 minutes
  - Flag update: 10 minutes
  - Build target: 10 minutes
  - Documentation: 5 minutes