Running web tests on Linux

1. Buildblink_tests (seeLinux-specific build instructions)
2. Checkout the web tests
   • If you have an entry in your.gclient file that includes “web_tests”, you may need to comment it out and sync.
   • You can run a subset of the tests by passing in a path relative tosrc/third_party/blink/web_tests/. For example,third_party/blink/tools/run_web_tests.py fast will only run the tests undersrc/third_party/blink/web_tests/fast/.
3. When the tests finish, any unexpected results should be displayed.

SeeWeb Tests for full documentation about set up and available options.

Pixel Tests

The pixel test results were generated on Ubuntu 10.4 (Lucid). If you're running a newer version of Ubuntu, you will get some pixel test failures due to changes in freetype or fonts. In this case, you can create a Lucid 64 chroot usingbuild/install-chroot.sh to compile and run tests.

Fonts

1. Make sure you have all the dependencies installed by running

build/install-build-deps.sh

2. Double check that

ls third_party/test_fonts/test_fonts/

is not empty and lists the fonts downloaded through thetest_fonts hook in the top levelDEPS file.

Plugins

Iffast/dom/object-plugin-hides-properties.html andplugins/embed-attributes-style.html are failing, try uninstallingtotem-mozilla from your system:

sudo apt-get remove totem-mozilla

Configuration tips

• Use an optimizedcontent_shell when rebaselining or running a lot of tests. (bug 8475 is about how the debug output differs from the optimized output.)

  ninja -C out/Release content_shell

• Make sure you have wdiff installed:sudo apt-get install wdiff to get prettier diff output.

• Some pixel tests may fail due to processor-specific rounding errors. Build using a chroot jail with Lucid 64-bit user space to be sure that your system matches the checked in baselines. You can usebuild/install-chroot.sh to set up a Lucid 64 chroot. Learn more aboutusing a linux chroot.

Getting a web test into a debugger

There are two ways:

1. Runcontent_shell directly rather than usingrun_web_tests.py. You will need to pass some options:
   • --no-timeout to give you plenty of time to debug
   • the fully qualified path of the web test (rather than relative toblink/web_tests).
2. Or, run as normal but with the--additional-drt-flag=--renderer-startup-dialog --additional-drt-flag=--no-timeout --timeout-ms=86400000 flags. The first one makes content_shell bring up a dialog before running, which then would let you attach to the process viagdb -p PID_OF_DUMPRENDERTREE. The others help avoid the test shell and DumpRenderTree timeouts during the debug session.

Using an embedded X server

If you try to use your computer while the tests are running, you may get annoyed as windows are opened and closed automatically. To get around this, you can create a separate X server for running the tests.

1. Install Xephyr (sudo apt-get install xserver-xephyr)
2. Start Xephyr as display 4:Xephyr :4 -screen 1024x768x24
3. Run the web tests in the Xephyr:DISPLAY=:4 run_web_tests.py

Xephyr supports debugging repainting. See theXephyr README for details. In brief:

1. XEPHYR_PAUSE=$((500*1000)) Xephyr ...etc... # 500 ms repaint flash
2. kill -USR1 $(pidof Xephyr)

If you don't want to see anything at all, you can use Xvfb (should already be installed).

1. Start Xvfb as display 4:Xvfb :4 -screen 0 1024x768x24
2. Run the web tests in the Xvfb:DISPLAY=:4 run_web_tests.py

Tiling Window managers

The web tests want to run with the window at a particular size down to the pixel level. This means if your window manager resizes the window it'll cause test failures. This is another good reason to use an embedded X server.

xmonad

In your.xmonad/xmonad.hs, change your config to include a manageHook along these lines:

test_shell_manage = className =? "Test_shell" --> doFloatmain = xmonad $  defaultConfig    { manageHook = test_shell_manage <+> manageHook defaultConfig    ...