gulpfile.js

// dependencies
var path = require('path'),
    gulp = require('gulp'),
    git = require('gulp-git'),
    bump = require('gulp-bump'),
    filter = require('gulp-filter'),
    tag_version = require('gulp-tag-version'),
    clean = require('gulp-clean'),
    concat = require('gulp-concat'),
    uglify = require('gulp-uglify'),
    rename = require('gulp-rename'),
    gutil = require('gulp-util'),
    file = require('fs');

function inc(importance) {
    // get all the files to bump version in
    return gulp.src(['./package.json', './bower.json'])
        // bump the version number in those files
        .pipe(bump({type: importance}))
        // save it back to filesystem
        .pipe(gulp.dest('./'))
        // commit the changed version number
        .pipe(git.commit('bumps package version'))

        // read only one file to get the version number
        .pipe(filter('package.json'))
        // **tag it in the repository**
        .pipe(tag_version());
}
function vers(){
    return JSON.parse(file.readFileSync('./package.json')).version;
}

gulp.task('clean', function () {
  return gulp.src('build', {read: false})
    .pipe(clean());
});

gulp.task('mini', function() {
  return gulp.src('js/*.js')
    .pipe(concat('gChart.js'))
    .pipe(rename('gChart-'+vers()+'.js'))
    .pipe(gulp.dest('build'))
    .pipe(uglify())
    .pipe(gulp.dest('build'))
    .on('error', gutil.log)
});

gulp.task('patch', function() { return inc('patch'); });
gulp.task('feature', function() { return inc('minor'); });
gulp.task('release', function() { return inc('major'); });