fix(preprocess): do not preprocess more files then simultaneousUploads opt

Author: AidasK

src/flow.js

@@ -1245,8 +1245,6 @@
             return;
           case 1:
             return;
-          case 2:
-            break;
         }
       }
       if (this.flowObj.opts.testChunks && !this.tested) {
@@ -1293,7 +1291,7 @@
      * @returns {string} 'pending', 'uploading', 'success', 'error'
      */
     status: function () {
-      if (this.pendingRetry) {
+      if (this.pendingRetry || this.preprocessState === 1) {
         // if pending retry then that's effectively the same as actively uploading,
         // there might just be a slight delay before the retry starts
         return 'uploading';

test/uploadSpec.js

@@ -388,6 +388,25 @@ describe('upload file', function() {
     expect(error).not.toHaveBeenCalled();
   });
 
+
+
+  it('should preprocess chunks and wait for preprocess to finish', function () {
+    flow.opts.simultaneousUploads = 1;
+    var preprocess = jasmine.createSpy('preprocess');
+    flow.opts.preprocess = preprocess;
+    flow.addFile(new Blob(['abc']));
+    flow.addFile(new Blob(['abca']));
+    var file = flow.files[0];
+    var secondFile = flow.files[1];
+    flow.upload();
+    expect(requests.length).toBe(0);
+    expect(preprocess).wasCalledWith(file.chunks[0]);
+    expect(preprocess).wasNotCalledWith(secondFile.chunks[0]);
+
+    flow.upload();
+    expect(preprocess).wasNotCalledWith(secondFile.chunks[0]);
+  });
+
   it('should have upload speed', function() {
     var clock = sinon.useFakeTimers();
     flow.opts.testChunks = false;