| Ash |
| --- |
| Ash is the "Aura Shell", the window manager and system UI for Chrome OS. |
| Ash uses the views UI toolkit (e.g. views::View, views::Widget, etc.) backed |
| by the aura native widget and layer implementations. |
| |
| Ash sits below chrome in the dependency graph (i.e. it cannot depend on code |
| in //chrome). It has a few dependencies on //content, but these are isolated |
| in their own module in //ash/content. This allows targets like ash_unittests |
| to build more quickly. |
| |
| Tests |
| ----- |
| Most tests should be added to the ash_unittests target. Tests that rely on |
| //content should be added to ash_content_unittests, but these should be rare. |
| |
| Tests can bring up most of the ash UI and simulate a login session by deriving |
| from AshTestBase. This is often needed to test code that depends on ash::Shell |
| and the controllers it owns. |
| |
| Mus+ash |
| ---------- |
| Ash is transitioning to use the mus window server and gpu process, found in |
| //services/ui. Ash continues to use aura, but aura is backed by mus. Code to |
| support mus is found in //ash/mus. There should be relatively few differences |
| between the pure aura and the aura-mus versions of ash. Ash can by run in mus |
| mode by passing the --mus command line flag. |
| |
| Ash is also transitioning to run as a mojo service in its own process. This |
| means that code in chrome cannot call into ash directly, but must use the mojo |
| interfaces in //ash/public/interfaces. |
| |
| Out-of-process Ash is referred to as "mash" (mojo ash). In-process ash is |
| referred to as "classic ash". Ash can run in either mode depending on the |
| --mash command line flag. |
| |
| Historical notes |
| ---------------- |
| Ash shipped on Windows for a couple years to support Windows 8 Metro mode. |
| Windows support was removed in 2016. |
