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# Purpose
A command-line tool for analysing javascript source, providing measurements of function length, number of arguments, and cyclomatic complexity.

NOTE: jshint now does most of these checks, http://www.elijahmanor.com/2012/09/control-complexity-of-your-javascript.html so you may not need this any more. Use jshint instead, it checks for a whole load of other things as well.

## Installation
    npm install jscheckstyle

## Usage
    jscheckstyle some-javascript.js some-other-javascript.js (default output as nice table on command line)
    jscheckstyle --violations some-javascript.js (will output rule-violating functions only)
    jscheckstyle --html some-javascript.js > output.html
    jscheckstyle --json some-javascript.js > output.json
    jscheckstyle --checkstyle some-javascript.js > output.xml (will output Java checkstyle-compatible output, useful for Jenkins)
    jscheckstyle --emacs some-javascript.js (produces output suitable for Emacs flymake - see flymake-jschecksyle.el)

## Rules
There are three rules at the moment which will be violated if:

* function length is greater than 30 lines
* number of arguments to a function is greater than 5
* cyclomatic complexity for a function is greater than 10

## Exclusion
To exclude certain directories or files from being checkstyled, simply create a .jscheckstyleignore file at current directory, and specify the directory or file name (relative to current directory) that you want to exclude.

## Configuration
It is possible to change the default rules by specifying different limits in comments before a function.

For example:

    /*
     * @jscheckstyle.functionLength=20
     * @jscheckstyle.numberOfArguments=10
     * @jscheckstyle.cyclomaticComplexity=30
     */
    function theFunction() {
        ...
    }


## History
Originally I started out modifying [jsmeter](http://jsmeter.info) to run as a command-line tool. Then I started hacking away, added some tests, the command-line interface, added the rules checking and the extra output types, replaced the parser with [node-burrito](https://github.com/substack/node-burrito) and then realised there wasn't much of jsmeter left. So this tool is inspired by, and owes a huge debt to, jsmeter - but there's very little of the original code to be found (possibly only the HTML output renderer).