Don't process directories or empty files (#71)

* don't process directories or empty files

fixes #67.

* add test, bump v, misc.

.gitignore

@@ -3,3 +3,4 @@
 node_modules
 test/**/*.generated.*
 test/**/*.min.css
+.DS_Store

LICENSE

@@ -1,4 +1,4 @@
-Copyright (c) 2018 scniro <scniro@outlook.com>
+Copyright (c) 2019 scniro <scniro@outlook.com>
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the

README.md

@@ -76,4 +76,4 @@ gulp.task('minify-css',() => {
 
 ## License
 
-[MIT](./LICENSE) © 2018 [scniro](https://github.com/scniro)
+[MIT](./LICENSE) © 2019 [scniro](https://github.com/scniro)

index.js

@@ -11,6 +11,9 @@ module.exports = (options, callback) => {
 
   return through.obj(function (file, enc, cb) {
 
+    if (file.isNull()) {
+      return cb(null, file);
+    }
     if (file.isStream()) {
       this.emit('error', new PluginError('gulp-clean-css', 'Streaming not supported!'));
       return cb(null, file);
@@ -28,6 +31,7 @@ module.exports = (options, callback) => {
     }
 
     new CleanCSS(_options).minify(content, (errors, css) => {
+
       if (errors) {
         return cb(errors.join(' '));
       }

index.spec.js

@@ -138,17 +138,25 @@ describe('gulp-clean-css: base functionality', () => {
   });
 
   it('should invoke optional callback with out options object supplied: return object hash', done => {
+
+    let called = false;
+
     gulp.src('test/fixtures/test.css')
-      .pipe(cleanCSS(details => {
+      .pipe(cleanCSS({}, details => {
+        called = true;
         details.stats.should.exist &&
         expect(details).to.have.ownProperty('stats') &&
         expect(details).to.have.ownProperty('errors') &&
         expect(details).to.have.ownProperty('warnings') &&
         expect(details).to.not.have.ownProperty('sourceMap');
       }))
       .on('data', (file) => {
+        //
+      })
+      .once('end', () => {
+        expect(called).to.be.true;
         done();
-      });
+      })
   });
 
   it('should invoke optional callback without options object supplied: return object hash with sourceMap: true; return correct hash', done => {
@@ -240,6 +248,20 @@ describe('gulp-clean-css: base functionality', () => {
         done();
       })
   });
+
+  it('should not process empty directories or files', done => {
+
+    gulp.src('./test/fixtures/very-empty/**')
+      .pipe(cleanCSS({}, detail => {
+        expect(detail.errors).to.be.empty;
+      }))
+      .on('data', file => {
+        //
+      })
+      .on('end', () => {
+        done();
+      });
+  })
 });
 
 describe('gulp-clean-css: rebase', () => {