This PR has evolved to encapsulate two related fixes that I can't really
untie anymore.
#2455 - Duplicating a tab that doesn't exist anymore
This was the bug I was originally fixing in #4429.
When the user tries to `duplicateTab` with a profile that doesn't exist
anymore (like might happen after a settings reload), don't crash.
As I was going about adding tests for this, got blocked by the fact that
the Terminal couldn't open _any_ panes while the `TerminalPage` was size
0x0. This had two theoretical solutions:
* Fake the `TerminalPage` into thinking it had a real size in the test -
probably possible, though I'm unsure how it would work in practice.
* Change `Pane`s to not require an `ActualWidth`, `ActualHeight` on
initialization.
Fortuately, the second option was something else that was already on my
backlog of bugs.
#4618 - `wt` command-line can't consistently parse more than one arg
Presently, the Terminal just arbitrarily dispatches a bunch of handlers
to try and handle all the commands provided on the commandline. That's
lead to a bunch of reports that not all the commands will always get
executed, nor will they all get executed in the same order.
This PR also changes the `TerminalPage` to be able to dispatch all the
commands sequentially, all at once in the startup. No longer will there
be a hot second where the commands seem to execute themselves in from of
the user - they'll all happen behind the scenes on startup.
This involved a couple other changes areound the `TerminalPage`
* I had to make sure that panes could be opened at a 0x0 size. Now they
use a star sizing based off the percentage of the parent they're
supposed to consume, so that when the parent _does_ get laid out,
they'll take the appropriate size of that parent.
* I had to do some math ahead of time to try and calculate what a
`SplitState::Automatic` would be evaluated as, despite the fact that
we don't actually know how big the pane will be.
* I had to ensure that `focus-tab` commands appropriately mark a single
tab as focused while we're in startup, without roundtripping to the
Dispatcher thread and back
## References
#4429 - the original PR for #2455#5047 - a follow-up task from discussion in #4429#4953 - a PR for making panes use star sizing, which was immensly
helpful for this PR.
## Detailed Description of the Pull Request / Additional comments
`CascadiaSettings::BuildSettings` can throw if the GUID doesn't exist.
This wraps those calls up with a try/catch.
It also adds a couple tests - a few `SettingsTests` for try/catching
this state. It also adds a XAML-y test in `TabTests` that creates a
`TerminalPage` and then performs som UI-like actions on it. This test
required a minor change to how we generate the new tab dropdown - in the
tests, `Application::Current()` is _not_ a `TerminalApp::App`, so it
doesn't have a `Logic()` to query. So wrap that in a try/catch as well.
While working on these tests, I found that we'd crash pretty agressively
for mysterious reasons if the TestHostApp became focused while the test
was running. This was due to a call in
`TSFInputControl::NotifyFocusEnter` that would callback to
`TSFInputControl::_layoutRequested`, which would crash on setting the
`MaxSize` of the canvas to a negative value. This PR includes a hotfix
for that bug as well.
## Validation Steps Performed
* Manual testing with a _lot_ of commands in a commandline
* run the tests
* Team tested in selfhost
Closes#2455Closes#4618
b3fa88eaed