feat(e2e): give the macOS test window a class by its accessibility subrole

--class was accepted and ignored on macOS, so the scenarios that match a window by
a class could not run. The test window now sets its accessibility subrole to the
class (NSWindow setAccessibilitySubrole), and the host passes the app id of spawn as
--class.

crates/komorebi-testwin/Cargo.toml

@@ -23,6 +23,9 @@ objc2-app-kit = { version = "0.3", default-features = false, features = [
   "NSScreen",
   "NSGraphics",
   "NSEvent",
+  "NSAccessibility",
+  "NSAccessibilityConstants",
+  "NSAccessibilityProtocols",
   "NSRunningApplication",
   "objc2-core-foundation",
   "libc",

crates/komorebi-testwin/src/appkit.rs

@@ -15,6 +15,7 @@ use std::time::Instant;
 use objc2::MainThreadMarker;
 use objc2::MainThreadOnly;
 use objc2::rc::Retained;
+use objc2_app_kit::NSAccessibility;
 use objc2_app_kit::NSApplication;
 use objc2_app_kit::NSApplicationActivationPolicy;
 use objc2_app_kit::NSBackingStoreType;
@@ -154,6 +155,11 @@ pub fn run(options: cli::Options) {
     // SAFETY: this program owns the window, so a close does not release it a second time.
     unsafe { window.setReleasedWhenClosed(false) };
     window.setTitle(&NSString::from_str(&options.title));
+    if let Some(class) = &options.class {
+        // a macOS window has no class: the daemon takes the accessibility subrole of a window for
+        // it, which a program is free to name as it likes
+        window.setAccessibilitySubrole(Some(&NSString::from_str(class)));
+    }
     if let Some(rgb) = options.color {
         window.setBackgroundColor(Some(&color(rgb)));
     }

crates/komorebi-testwin/src/cli.rs

@@ -9,7 +9,8 @@ pub struct Options {
     pub title: String,
     /// The size of the window, in pixels (points on macOS).
     pub size: (i32, i32),
-    /// The window class on Windows; no other platform has one, and ignores it.
+    /// The window class on Windows; on macOS, which has none, the accessibility subrole of the
+    /// window, which is what the daemon takes for one; no other platform has one, and ignores it.
     pub class: Option<String>,
     /// `0xRRGGBB`.
     pub color: Option<u32>,

e2e/platforms/tart_macos/macos_platform.py

@@ -254,8 +254,11 @@ class MacosPlatform:
         rename_to: str | None = None,
         after: float = 0,
     ) -> Client:
-        # `app_id` is a window class, which a macOS window does not have: it is not passed
         args = ["--title", title]
+        if app_id is not None:
+            # a macOS window has no class: the daemon takes its accessibility subrole for one, which
+            # the test window is given as this
+            args += ["--class", app_id]
         if rename_to is not None:
             # the window gives itself this title `after` seconds from now
             args += ["--rename-to", rename_to, "--after", str(after)]