Running layout tests using the content shell

Basic usage

Layout tests can be run with content_shell. To just dump the render tree, use the --run-layout-test flag:

out/Default/content_shell --run-layout-test foo.html


If you want to run layout tests, build the target blink_tests; this includes all the other binaries required to run the tests.


You can run layout tests using run-webkit-tests (in src/third_party/WebKit/Tools/Scripts).

third_party/WebKit/Tools/Scripts/run-webkit-tests storage/indexeddb

or execute the shell directly:

out/Default/content_shell --remote-debugging-port=9222

This allows you see how your changes look in Chromium, and even connect with devtools (by going to from another window) to inspect your freshly compiled Blink.

On the Mac, use Content, not content_shell.

out/Default/Content\\ Shell --remote-debugging-port=9222

Debugging Renderer Crashes

To debug a renderer crash, ask Content Shell to wait for you to attach a debugger once it spawns a renderer process by adding the --renderer-startup-dialog flag:

out/Default/content_shell --renderer-startup-dialog

Debugging workers and other subprocesses is simpler with --wait-for-debugger-children, which can have one of two values: plugin or renderer.

Future Work

Reusing existing testing objects

To avoid writing (and maintaining!) yet another test controller, it is desirable to reuse an existing test controller. A possible solution would be to change DRT‘s test controller to not depend on DRT’s implementation of the Blink objects, but rather on the Blink interfaces. In addition, we would need to extract an interface from the test shell object that can be implemented by content shell. This would allow for directly using DRT's test controller in content shell.