Desktop Chrome Instructions

Instructions that are relevant when targeting desktop platforms (when {OUT_DIR}/args.gn contains target_os="linux", target_os="mac", target_os="windows", or when target_os is not set).

Context

Before starting any tasks, you MUST read the following files to better understand design principles and commonly components within Chrome.

//docs/chrome_browser_design_principles.md
//docs/ui/views/overview.md

Build Targets

Always build relevant targets after making edits. Typical targets could be:

chrome - the main binary for desktop chrome
unit_tests - unit-style tests for desktop chrome
browser_tests - integration test for desktop chrome
interactive_ui_tests - integration tests for desktop chrome that cannot be run in parallel as they require exclusive control of OS or window-manager.
blink_tests - target containing content_shell and dependencies needed to run Blink web tests (run_web_tests.py).

Running Tests on Linux

When running test targets on Linux, execute them under a virtual X server (Xvfb) to avoid display dependency errors and prevent test windows from stealing focus on the desktop.

C++ Test Binaries (unit_tests, browser_tests, interactive_ui_tests): Prefix invocations with testing/xvfb.py as described in //docs/linux/debugging.md:
bash
```
testing/xvfb.py out/Default/browser_tests --gtest_filter=TestName.*
```
Blink Web Tests (blink_tests / run_web_tests.py): When running Blink web tests on Linux as described in //docs/testing/web_tests_linux.md, run under an Xvfb display:
bash
```
Xvfb :4 -screen 0 1024x768x24 &
DISPLAY=:4 run_web_tests.py
```