Rust Language Guide¶

linthis uses clippy for linting and rustfmt for formatting Rust code.

Supported File Extensions¶

.rs

Required Tools¶

Linter: clippy¶

# Install via rustup (recommended)
rustup component add clippy

# Verify installation
cargo clippy --version

Formatter: rustfmt¶

# Install via rustup (recommended)
rustup component add rustfmt

# Verify installation
rustfmt --version

Configuration¶

Basic Example¶

# .linthis/config.toml

[rust]
max_complexity = 15
excludes = ["target/**"]

Disable Specific Clippy Lints¶

[rust.rules]
disable = [
    "clippy::needless_return",
    "clippy::too_many_arguments",
    "clippy::type_complexity"
]

Change Severity¶

[rust.rules.severity]
"clippy::unwrap_used" = "error"    # Treat unwrap as error
"clippy::todo" = "warning"         # Keep TODO as warning

Custom Rules¶

[[rules.custom]]
code = "rust/no-println"
pattern = "println!"
message = "Use log macros instead of println!"
severity = "warning"
suggestion = "Use log::info!, log::debug!, etc."
languages = ["rust"]

CLI Usage¶

# Check Rust files only
linthis -c --lang rust

# Format Rust files only
linthis -f --lang rust

# Check specific file
linthis -c src/main.rs

Clippy Configuration¶

linthis respects your .clippy.toml or clippy.toml configuration file:

# clippy.toml
cognitive-complexity-threshold = 15
too-many-arguments-threshold = 8

Common Issues¶

Clippy not found¶

Warning: No rust linter available for rust files
  Install: rustup component add clippy

Solution: Run rustup component add clippy

Slow first run¶

Clippy compiles your project on first run. Subsequent runs use incremental compilation.

Conflicting with project clippy config¶

linthis uses the same clippy configuration as cargo clippy. Your project's clippy.toml settings are respected.

Best Practices¶

Use workspace-level config: Place .linthis/config.toml at workspace root
CI integration: Run linthis -c --lang rust in CI for consistent checks
Complexity limits: Set max_complexity = 15 for maintainable code
Unwrap handling: Consider treating clippy::unwrap_used as error in production code