code-format

name	code-format
description	Format Rust and shell script code automatically. Use immediately after editing .rs/.sh files or the install script, when user mentions formatting, code style, or before commits/PRs. Ensures consistent code style following project conventions.

Code Formatting Skill

This skill provides code formatting operations for the project codebase, which is a single-crate Rust workspace with shell scripts.

When to Use This Skill

Use this skill when you need to:

• Format code after editing Rust or shell script files
• Format the install script after making changes
• Check if code meets formatting standards
• Ensure code formatting compliance before commits

Command Selection Rules

Choose the appropriate command based on the number of files edited:

Files Edited	File Type	Command to Use	Rationale
1-2 files	Rust	just fmt-rs-file <file> (per file)	Faster, targeted formatting
3+ files	Rust	just fmt-rs (global)	More efficient than multiple per-file calls
Any	Shell	just fmt-sh	Formats the install script

Decision process:

1. Count the number of files you edited (by type: Rust or Shell)
2. If 2 or fewer Rust files: run just fmt-rs-file for each file
3. If 3 or more Rust files: run the global command just fmt-rs
4. For shell scripts: always run just fmt-sh (currently only formats the install script)

Available Commands

Format Rust Code

just fmt-rs

Formats all Rust code using cargo +nightly fmt --all. This is the primary formatting command.

Alias: just fmt (same as fmt-rs)

Check Rust Formatting

just fmt-rs-check

Checks Rust code formatting without making changes using cargo +nightly fmt --all -- --check.

Alias: just fmt-check (same as fmt-rs-check)

Format Specific Rust File

just fmt-rs-file <FILE>

Formats a specific Rust file using cargo +nightly fmt.

Examples:

• just fmt-rs-file ampup/src/main.rs - formats a Rust file
• just fmt-rs-file ampup/src/config.rs - formats another Rust file

Format Shell Scripts

just fmt-sh

Formats shell scripts. Currently formats the install script.

Requirements: Requires shfmt to be installed. The command will provide installation instructions if not available.

Check Shell Script Formatting

just fmt-sh-check

Checks shell script formatting without making changes.

Important Guidelines

Format Before Checks/Commit

Format code when you finish a coherent chunk of work and before running checks or committing.

This is a critical requirement from the project's development workflow:

• Do not skip formatting before checks/commit
• Use the Command Selection Rules above to choose the right command
• Run formatting before any check or test commands

Example Workflows

Single file edit:

1. Edit a Rust file: ampup/src/config.rs
2. When ready to validate, run: just fmt-rs-file ampup/src/config.rs
3. Then run checks

Multiple files edit (3+):

1. Edit multiple Rust files across the codebase
2. When ready to validate, run: just fmt-rs
3. Then run checks

Common Mistakes to Avoid

❌ Anti-patterns

• Never run cargo fmt directly - Use just fmt-rs-file or just fmt-rs
• Never run rustfmt directly - The justfile includes proper flags
• Never run shfmt directly - Use just fmt-sh
• Never skip formatting before checks/commit - Even "minor" edits need formatting
• Never use just fmt-rs for 1-2 files - Use just fmt-rs-file <file> for efficiency
• Never use just fmt-rs-file for 3+ files - Use just fmt-rs for efficiency

✅ Best Practices

• Format before running checks/tests or before committing
• Use just fmt-rs-file for 1-2 files (faster, targeted)
• Use just fmt-rs for 3+ files (more efficient)
• Run format check commands to verify formatting before commits

Next Steps

After formatting your code:

1. Check compilation → See .agents/skills/code-check/SKILL.md
2. Run clippy → See .agents/skills/code-check/SKILL.md
3. Run targeted tests when warranted → See .agents/skills/code-test/SKILL.md