From 07e20db42dbf866e76ae52f8f7dfd6274e1f1045 Mon Sep 17 00:00:00 2001
From: jansson <jansson@webrtc.org>
Date: Wed, 12 Apr 2017 01:36:02 -0700
Subject: [PATCH] return comparevideos stdout and fix missing device case

BUG=webrtc:7203
NOTRY=True

Review-Url: https://codereview.webrtc.org/2809913002
Cr-Commit-Position: refs/heads/master@{#17665}
---
 webrtc/tools/video_analysis.py      | 43 +++++++++++++++++------------
 webrtc/tools/video_analysis_test.py |  9 ++++++
 2 files changed, 34 insertions(+), 18 deletions(-)

diff --git a/webrtc/tools/video_analysis.py b/webrtc/tools/video_analysis.py
index b13543d65a..68575f3e26 100755
--- a/webrtc/tools/video_analysis.py
+++ b/webrtc/tools/video_analysis.py
@@ -184,18 +184,23 @@ def FindUsbPortForV4lDevices(ref_video_device, test_video_device):
 
   # Split on the driver folder first since we are only interested in the
   # folders thereafter.
-  ref_path = str(v4l_ref_device).split('driver')[1].split('/')
-  test_path = str(v4l_test_device).split('driver')[1].split('/')
-  paths.append(ref_path)
-  paths.append(test_path)
+  try:
+    ref_path = str(v4l_ref_device).split('driver')[1].split('/')
+    test_path = str(v4l_test_device).split('driver')[1].split('/')
+  except IndexError:
+    print 'Could not find one or both of the specified recording devices.'
+  else:
+    paths.append(ref_path)
+    paths.append(test_path)
+
+    for path in paths:
+      for usb_id in path:
+        # Look for : separator and then use the first element in the list.
+        # E.g 3-3.1:1.0 split on : and [0] becomes 3-3.1 which can be used
+        # for bind/unbind.
+        if ':' in usb_id:
+          usb_ports.append(usb_id.split(':')[0])
 
-  for path in paths:
-    for usb_id in path:
-      # Look for : separator and then use the first element in the list.
-      # E.g 3-3.1:1.0 split on : and [0] becomes 3-3.1 which can be used
-      # for bind/unbind.
-      if ':' in usb_id:
-        usb_ports.append(usb_id.split(':')[0])
   return usb_ports
 
 
@@ -448,13 +453,15 @@ def CompareVideos(options, cropped_ref_file, cropped_test_file):
   ]
 
   with open(result_file_name, 'w') as f:
-    compare_video_recordings = subprocess.Popen(compare_cmd, stdout=f)
-    compare_video_recordings.wait()
-  if compare_video_recordings.returncode != 0:
-    raise CompareVideosError('Failed to perform comparison.')
-  else:
-    print 'Result recorded to: ' + os.path.abspath(result_file_name)
-    print 'Comparison done!'
+    try:
+      compare_video_recordings = subprocess.check_output(compare_cmd)
+      f.write(compare_video_recordings)
+    except subprocess.CalledProcessError as error:
+      raise CompareVideosError('Failed to perform comparison: %s' % error)
+    else:
+      print 'Result recorded to: %s' % os.path.abspath(result_file_name)
+      print 'Comparison done!'
+      return compare_video_recordings
 
 
 def main():
diff --git a/webrtc/tools/video_analysis_test.py b/webrtc/tools/video_analysis_test.py
index f4cd74b31c..483632bc48 100755
--- a/webrtc/tools/video_analysis_test.py
+++ b/webrtc/tools/video_analysis_test.py
@@ -56,5 +56,14 @@ class RunVideoAnalysisTest(unittest.TestCase):
     self.assertEqual(FindUsbPortForV4lDevices('video0', 'video1'), long_usb_ids)
 
 
+  def testFindUSBPortForV4lDevicesNoDevice(self):
+    noDeviceFound = ('')
+    V4lDevice = ('/sys/bus/usb/devices/usb1/1-1/driver/3-2/3-2.1:1.0/'
+                  'video4linux/video1')
+    self.setGlobPath(noDeviceFound, V4lDevice)
+    empty_list = []
+    self.assertEqual(FindUsbPortForV4lDevices('video0', 'video1'), empty_list)
+
+
 if __name__ == "__main__":
   unittest.main()