Skipping WebRTC Firefox inteop test if there's no webcam on the system.

chrome/browser/media/chrome_webrtc_apprtc_browsertest.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/command_line.h"
+#include "base/files/file_enumerator.h"
 #include "base/path_service.h"
 #include "base/process/launch.h"
 #include "base/rand_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/win/windows_version.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/media/webrtc_browsertest_base.h"
 #include "chrome/browser/media/webrtc_browsertest_common.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_tabstrip.h"
@@ skipping 14 matching lines @@
     "  \"url\"         : \"svn://svn.chromium.org/chrome/trunk/deps/"
     "third_party/webrtc/webrtc.DEPS\",\n"
     "}";
 const char kTitlePageOfAppEngineAdminPage[] = "Instances";
 
 
 // WebRTC-AppRTC integration test. Requires a real webcam and microphone
 // on the running system. This test is not meant to run in the main browser
 // test suite since normal tester machines do not have webcams. Chrome will use
 // its fake camera for both tests, but Firefox will use the real webcam in the
-// Firefox interop test.
+// Firefox interop test. Thus, this test must on a machine with a real webcam.
 //
 // This test will bring up a AppRTC instance on localhost and verify that the
 // call gets up when connecting to the same room from two tabs in a browser.
 class WebRtcApprtcBrowserTest : public WebRtcTestBase {
  public:
   WebRtcApprtcBrowserTest()
       : dev_appserver_(base::kNullProcessHandle),
         firefox_(base::kNullProcessHandle) {
   }
 
@@ skipping 126 matching lines @@
 
     CommandLine command_line(firefox_launcher);
     command_line.AppendSwitchPath("--binary", firefox_binary);
     command_line.AppendSwitchASCII("--webpage", url.spec());
 
     VLOG(1) << "Running " << command_line.GetCommandLineString();
     return base::LaunchProcess(command_line, base::LaunchOptions(),
                                &firefox_);
   }
 
+  bool HasWebcamOnSystem() {
+#if defined(OS_LINUX)
+    // Implementation note: normally we would be able to figure this out with
+    // MediaStreamTrack.getSources, but we can't ask Chrome since it runs in
+    // fake device mode where it will not enumerate webcams on the system.
+    // Therefore, look for /dev/video* entries directly since this test only
+    // runs on Linux for now anyway.
+    base::FileEnumerator dev_video(base::FilePath(FILE_PATH_LITERAL("/dev")),
+                                   false, base::FileEnumerator::FILES,
+                                   FILE_PATH_LITERAL("video*"));
+    return !dev_video.Next().empty();
+#endif
+    NOTREACHED();
+    return false;
+  }
+
  private:
   base::ProcessHandle dev_appserver_;
   base::ProcessHandle firefox_;
 };
 
 IN_PROC_BROWSER_TEST_F(WebRtcApprtcBrowserTest, MANUAL_WorksOnApprtc) {
   // TODO(mcasas): Remove Win version filtering when this bug gets fixed:
   // http://code.google.com/p/webrtc/issues/detail?id=2703
 #if defined(OS_WIN)
   if (base::win::GetVersion() < base::win::VERSION_VISTA)
@@ skipping 26 matching lines @@
 #define MAYBE_MANUAL_FirefoxApprtcInteropTest DISABLED_MANUAL_FirefoxApprtcInteropTest
 #endif
 
 IN_PROC_BROWSER_TEST_F(WebRtcApprtcBrowserTest,
                        MAYBE_MANUAL_FirefoxApprtcInteropTest) {
   // Disabled on Win XP: http://code.google.com/p/webrtc/issues/detail?id=2703.
 #if defined(OS_WIN)
   if (base::win::GetVersion() < base::win::VERSION_VISTA)
     return;
 #endif
+  if (!HasWebcamOnSystem()) {
+    LOG(INFO)
+        << "Didn't find a webcam on the system; skipping test since Firefox "
+        << "needs to be able to acquire a webcam.";
+    return;
+  }
 
   DetectErrorsInJavaScript();
   ASSERT_TRUE(LaunchApprtcInstanceOnLocalhost());
   while (!LocalApprtcInstanceIsUp())
     VLOG(1) << "Waiting for AppRTC to come up...";
 
   GURL room_url = GURL(base::StringPrintf("http://localhost:9999?r=room_%d",
                                           base::RandInt(0, 65536)));
   content::WebContents* chrome_tab = OpenPageAndAcceptUserMedia(room_url);
 
   ASSERT_TRUE(LaunchFirefoxWithUrl(room_url));
 
   ASSERT_TRUE(WaitForCallToComeUp(chrome_tab));
 
   // Ensure Firefox manages to send video our way.
   ASSERT_TRUE(DetectRemoteVideoPlaying(chrome_tab));
 }