Mojo Format Skill

Format Mojo code files to ensure consistent style.

When to Use

Preparing code for commit
Pre-commit hook reports formatting issues
Code review requests formatting fixes
Verifying formatting compliance

Quick Reference

# Format single file
pixi run mojo format path/to/file.mojo

# Format directory
pixi run mojo format `find src/ -name "*.mojo"`

# Check without modifying
pixi run mojo format --check path/to/file.mojo

Workflow

Identify files - Single file or directory
Run formatter - pixi run mojo format <path>
Verify changes - Review formatted output
Commit - Stage and commit formatted code

Mojo-Specific Notes

Formats indentation (4 spaces), line length, spacing around operators
Does NOT change logic, variable names, or comment content
Preserves all comments, only adjusts spacing
Safe to run multiple times (idempotent)

Error Handling

| Error | Cause | Solution | |-------|-------|----------| | Syntax error | Invalid Mojo syntax | Fix syntax before formatting | | File not found | Wrong path | Verify file exists | | Permission denied | File permissions | Check chmod settings | | Mojo not installed | Missing Mojo | Install via pixi or Magic |

References

.claude/shared/mojo-guidelines.md - Mojo syntax standards
.pre-commit-config.yaml - Pre-commit hook configuration