gtk: nuke the legacy apprt from orbit (ghostty-org#8520)

We don't really have any large outstanding regressions on -ng to warrant
keeping this alive anymore. ¡Adiós!

Author: mitchellh

.github/workflows/test.yml

@@ -22,7 +22,6 @@ jobs:
       - build-macos-matrix
       - build-windows
       - test
-      - test-gtk
       - test-gtk-ng
       - test-sentry-linux
       - test-macos
@@ -492,65 +491,13 @@ jobs:
       - name: test
         run: nix develop -c zig build -Dapp-runtime=none test
 
-      - name: Test GTK Build
-        run: nix develop -c zig build -Dapp-runtime=gtk -Demit-docs -Demit-webdata
-
       - name: Test GTK-NG Build
         run: nix develop -c zig build -Dapp-runtime=gtk-ng -Demit-docs -Demit-webdata
 
       # This relies on the cache being populated by the commands above.
       - name: Test System Build
         run: nix develop -c zig build --system ${ZIG_GLOBAL_CACHE_DIR}/p
 
-  test-gtk:
-    strategy:
-      fail-fast: false
-      matrix:
-        x11: ["true", "false"]
-        wayland: ["true", "false"]
-    name: GTK x11=${{ matrix.x11 }} wayland=${{ matrix.wayland }}
-    runs-on: namespace-profile-ghostty-sm
-    needs: test
-    env:
-      ZIG_LOCAL_CACHE_DIR: /zig/local-cache
-      ZIG_GLOBAL_CACHE_DIR: /zig/global-cache
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
-
-      - name: Setup Cache
-        uses: namespacelabs/nscloud-cache-action@a289cf5d2fcd6874376aa92f0ef7f99dc923592a # v1.2.17
-        with:
-          path: |
-            /nix
-            /zig
-
-      # Install Nix and use that to run our tests so our environment matches exactly.
-      - uses: cachix/install-nix-action@56a7bb7b56d9a92d4fd1bc05758de7eea4a370a8 # v31.6.0
-        with:
-          nix_path: nixpkgs=channel:nixos-unstable
-      - uses: cachix/cachix-action@0fc020193b5a1fa3ac4575aa3a7d3aa6a35435ad # v16
-        with:
-          name: ghostty
-          authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
-
-      - name: Test
-        run: |
-          nix develop -c \
-            zig build \
-            -Dapp-runtime=gtk \
-            -Dgtk-x11=${{ matrix.x11 }} \
-            -Dgtk-wayland=${{ matrix.wayland }} \
-            test
-
-      - name: Build
-        run: |
-          nix develop -c \
-            zig build \
-            -Dapp-runtime=gtk \
-            -Dgtk-x11=${{ matrix.x11 }} \
-            -Dgtk-wayland=${{ matrix.wayland }}
-
   test-gtk-ng:
     strategy:
       fail-fast: false

CODEOWNERS

@@ -118,7 +118,6 @@
 /pkg/harfbuzz/ @ghostty-org/font
 
 # GTK
-/src/apprt/gtk/ @ghostty-org/gtk
 /src/apprt/gtk-ng/ @ghostty-org/gtk
 /src/os/cgroup.zig @ghostty-org/gtk
 /src/os/flatpak.zig @ghostty-org/gtk

src/apprt.zig

@@ -16,7 +16,6 @@ const structs = @import("apprt/structs.zig");
 
 pub const action = @import("apprt/action.zig");
 pub const ipc = @import("apprt/ipc.zig");
-pub const gtk = @import("apprt/gtk.zig");
 pub const gtk_ng = @import("apprt/gtk-ng.zig");
 pub const none = @import("apprt/none.zig");
 pub const browser = @import("apprt/browser.zig");
@@ -43,7 +42,6 @@ pub const SurfaceSize = structs.SurfaceSize;
 pub const runtime = switch (build_config.artifact) {
     .exe => switch (build_config.app_runtime) {
         .none => none,
-        .gtk => gtk,
         .@"gtk-ng" => gtk_ng,
     },
     .lib => embedded,
@@ -64,11 +62,6 @@ pub const Runtime = enum {
     /// approach to building the application.
     @"gtk-ng",
 
-    /// GTK-backed. Rich windowed application. GTK is dynamically linked.
-    /// WARNING: Deprecated. This will be removed very soon. All bug fixes
-    /// and features should go into the gtk-ng backend.
-    gtk,
-
     pub fn default(target: std.Target) Runtime {
         return switch (target.os.tag) {
             // The Linux and FreeBSD default is GTK because it is a full

src/apprt/action.zig

@@ -542,7 +542,7 @@ pub const InitialSize = extern struct {
 
     /// Make this a valid gobject if we're in a GTK environment.
     pub const getGObjectType = switch (build_config.app_runtime) {
-        .gtk, .@"gtk-ng" => @import("gobject").ext.defineBoxed(
+        .@"gtk-ng" => @import("gobject").ext.defineBoxed(
             InitialSize,
             .{ .name = "GhosttyApprtInitialSize" },
         ),