programmingthomas / Knyt

A command line tool for validating Objective-C style

Knyt is a command line tool written in Objective-C that parses Objective-C files and validates that they conform to the New York Times Objective-C style guide, reporting any errors that it finds.

##Current support

• Spaces are used for indentation instead of tabs
• The number of spaces used in indentation is a multiple of four
• Opening braces must be at the end of a line (Egyptian style)
• There is a space after the scope of an Objective-C method declaration
• Classes have a three letter prefix
• One line if, else if, else, for, while and switch statements aren't used
• CGGeometry functions are used in place of directly accessing size or origin of rectangles
• NS_ENUM() is used in place of enum
• Comparisons to YES, NO and nil don't happen
• instancetype is returned by init methods rather than id
• dealloc methods should precede init methods
• Literals should be used instead of class/instance methods of NSArray, NSDictionary or NSNumber
• Constants should be declared with types as static variables rather than macros
• Optional: Apache license in current form at the top of files

Knyt won't support checking for all of the rules described in the style guide, especially where it is difficult to identify failures (such as dot syntax being used or not used for something that is or isn't a property) or the rules aren't strict (such as the rules for ternery operators). This tool checks the majority of the rules described in the style guide, but only covers those explicitly related to source code (i.e. anything to do with projects is ignored).

##Usage

The most basic usage is ./knyt -dr /path/to/directory to validate a directory of Objective-C files (searches for all .h and .m files). You can either build Knyt and use the executable or run from Xcode by editing the scheme. Flags:

• -f For a file (followed by its path)
• -d For a directory (followed by a directory path)
• -dr To recursively search a directory (followed by a directory path)
• You can also use the following to apply additional non-standard rules:
  • -apache Check files have the Apache license format in the same style as the Knyt source files (was written to validate this project!)

##Development

Knyt is currently in alpha. It is written according to the style guide that it is based off of!

##License See the license file for the Apache 2.0 license.