An experimental tool to enforce Swift style and conventions, loosely based on GitHub’s Swift Style Guide.

SwiftLint hooks into Clang and SourceKit to use the AST representation of your source files for more accurate results.

Installation

Using Homebrew

brew install swiftlint

You can also install SwiftLint by downloading SwiftLint.pkg from the latest GitHub release and running it.

You can also build from source by cloning this project and running git submodule update --init --recursive; make install (Xcode 7 Beta 6 required).

Usage

Xcode

Integrate SwiftLint into an Xcode scheme to get warnings and errors displayed in the IDE. Just add a new “Run Script Phase” with /usr/local/bin/swiftlint as its contents.

Atom

To integrate SwiftLint with Atom install the linter-swiftlint package from APM.

Command Line

$ swiftlint help
Available commands:

   help      Display general or command-specific help
   lint      Print lint warnings and errors for the Swift files in the current directory (default command)
   rules     Display the list of rules and their identifiers
   version   Display the current version of SwiftLint

Run swiftlint in the directory containing the Swift files to lint. Directories will be searched recursively.

Rules

There are only a small number of rules currently implemented, but we hope the Swift community (that’s you!) will contribute more over time. Pull requests are encouraged.

The rules that are currently implemented are mostly there as a starting point and are subject to change.

See the Source/SwiftLintFramework/Rules directory to see the currently implemented rules.

Disable a rule in code

Rules can be disabled with a comment inside a source file with the following format:

/// swiftlint:disable <rule>

The rule will be disabled until the end of the file or until the linter sees a matching enable comment:

/// swiftlint:enable <rule>

For example:

/// swiftlint:disable colon
let noWarning :String = "" // No warning about colons immediately after variable names!
/// swiftlint:enable colon
let yesWarning :String = "" // Warning generated about colons immediately after variable names

Run swiftlint rules to print a list of all available rules and their identifiers.

Configuration

Configure SwiftLint by adding a .swiftlint.yml file from the directory you’ll run SwiftLint from. The following parameters can be configured:

disabled_rules: # rule identifiers to exclude from running
  - colon
  - control_statement
  - file_length
  - force_cast
  - function_body_length
  - leading_whitespace
  - line_length
  - nesting
  - operator_whitespace
  - return_arrow_whitespace
  - todo
  - trailing_newline
  - trailing_whitespace
  - type_body_length
  - type_name
  - variable_name
included: # paths to include during linting. `--path` is ignored if present. takes precendence over `excluded`.
  - Source
excluded: # paths to ignore during linting. overridden by `included`.
  - Carthage
  - Pods

License

MIT licensed.