Nativefier/gulp/tests/mocha.js

import gulp from 'gulp';
import PATHS from './../helpers/src-paths';

import istanbul from 'gulp-istanbul';
import {Instrumenter} from 'isparta';
import mocha from 'gulp-mocha';

gulp.task('mocha', done => {
    gulp.src([PATHS.CLI_SRC_JS, '!src/cli.js'])
        .pipe(istanbul({
            instrumenter: Instrumenter,
            includeUntested: true
        }))
        .pipe(istanbul.hookRequire()) // Force `require` to return covered files
        .on('finish', () => {
            return gulp.src(PATHS.TEST_SRC, {read: false})
                .pipe(mocha({
                    compilers: 'js:babel-core/register',
                    recursive: true
                }))
                .pipe(istanbul.writeReports({
                    dir: './coverage',
                    reporters: ['lcov'],
                    reportOpts: {dir: './coverage'}
                }))
                .on('end', done);
        });
});

gulp.task('tdd', ['mocha'], () => {
    return gulp.watch(['src/**/*.js', 'test/**/*.js'], ['mocha']);
});