precommit-hook/bin/pre-commit

#!/usr/bin/env node

// requires
var exec = require('child_process').exec;
var path = require('path');
var fs = require('fs');

// some status strings
var fail = '\x1B[31mfailed!\x1B[39m';
var ok = '\x1B[32mok\x1B[39m';
var notfound = '\x1B[33mn/a\x1B[39m (no script found)';
var skipped = '\x1B[33mn/a\x1B[39m (skipped)';

// config
var projectRoot = '{{projectRoot}}'; // lame templating so this gets populated correctly
var config = require(path.join(projectRoot, 'package.json'));
var myconfig = config.config && config.config.precommit ? config.config.precommit : undefined;

// set up environment
var pathKey;
var pathSep = process.platform === 'win32' ? ';' : ':';
var env = {};
for (var key in process.env) {
    if (key.toLowerCase() === 'path') {
        pathKey = key;
    }

    env[key] = process.env[key];
}
env[pathKey] = path.join(projectRoot, 'node_modules', '.bin') + pathSep + env[pathKey];

// run the command for the given property
function runCmd(prop, done) {
    var skip = myconfig ? !myconfig[prop] : false;
    var cmd = config.scripts  && config.scripts[prop] ? config.scripts[prop] : prop === 'lint' ? 'jshint .' : undefined;
    var pad = '';
    for (var i = 0; i < (8 - prop.length); i++) {
        pad += ' ';
    }
    
    process.stdout.write('running ' + prop + ': ' + pad);

    if (skip) {
        console.log(skipped);
        return done();
    }

    if (!cmd) {
        console.log(notfound);
        return done();
    }

    cmd = (process.platform === 'win32' ? 'cmd /c ' : 'sh -c ') + '\"' + cmd + '\"';

    exec(cmd, { cwd: projectRoot, env: env }, function (err, stdout, stderr) {
        if (err) {
            console.log(fail);
            console.log(stdout);
            console.log(stderr);
            exit(err.code, process.exit);
        } else {
            console.log(ok);
            exit(0, done);
        }
    });
}

// this method shamelessly adapted from https://github.com/cowbody/node-exit
function exit(code, callback) {
    var streams = [process.stdout, process.stderr];
    var drainCount = 0;

    function tryToExit() {
        if (drainCount === streams.length) {
            callback(code);
        }
    }

    streams.forEach(function (stream) {
        if (stream.bufferSize === 0) {
            drainCount++;
        } else {
            stream.write('', 'utf-8', function () {
                drainCount++;
                tryToExit();
            });

            stream.write = function () {};
        }
    });

    tryToExit();
}

console.log('running pre-commit checks...');
runCmd('lint', function () {
    runCmd('validate', function () {
        runCmd('test', process.exit);
    });
});