build: zig build test runs Xcode tests on macOS

Related to #7879

This commit updates `zig build test` to run Xcode tests, too. These run
in parallel to the Zig tests, so they don't add any time to the test.

The Xcode tests will _not_ run when: (1) the target is not macOS, or (2)
the `-Dtest-filter` option is non-empty. This makes it so that this
change doesn't affect non-macOS and doesn't affect the general dev cycle
because you usually will run `-Dtest-filter` when developing a core
feature.

I didn't add a step to only run Xcode tests because I find that when I'm
working in Xcode I'm probably going to run the tests from there anyways.
The integration with `zig build test` is just a convenience, especially
around CI.

Speaking of CI, this change also makes it so this will run in CI.

build.zig

@@ -8,7 +8,22 @@ comptime {
 }
 
 pub fn build(b: *std.Build) !void {
+    // This defines all the available build options (e.g. `-D`).
     const config = try buildpkg.Config.init(b);
+    const test_filter = b.option(
+        []const u8,
+        "test-filter",
+        "Filter for test. Only applies to Zig tests.",
+    );
+
+    // All our steps which we'll hook up later. The steps are shown
+    // up here just so that they are more self-documenting.
+    const run_step = b.step("run", "Run the app");
+    const test_step = b.step("test", "Run all tests");
+    const translations_step = b.step(
+        "update-translations",
+        "Update translation files",
+    );
 
     // Ghostty resources like terminfo, shell integration, themes, etc.
     const resources = try buildpkg.GhosttyResources.init(b, &config);
@@ -131,7 +146,6 @@ pub fn build(b: *std.Build) !void {
                 b.getInstallPath(.prefix, "share/ghostty"),
             );
 
-            const run_step = b.step("run", "Run the app");
             run_step.dependOn(&run_cmd.step);
             break :run;
         }
@@ -157,16 +171,18 @@ pub fn build(b: *std.Build) !void {
                 },
             );
 
-            const run_step = b.step("run", "Run the app");
+            // Run uses the native macOS app
             run_step.dependOn(&macos_app_native_only.open.step);
+
+            // If we have no test filters, install the tests too
+            if (test_filter == null) {
+                macos_app_native_only.addTestStepDependencies(test_step);
+            }
         }
     }
 
     // Tests
     {
-        const test_step = b.step("test", "Run all tests");
-        const test_filter = b.option([]const u8, "test-filter", "Filter for test");
-
         const test_exe = b.addTest(.{
             .name = "ghostty-test",
             .filters = if (test_filter) |v| &.{v} else &.{},
@@ -180,18 +196,13 @@ pub fn build(b: *std.Build) !void {
             }),
         });
 
-        {
+        if (config.emit_test_exe) b.installArtifact(test_exe);
-            if (config.emit_test_exe) b.installArtifact(test_exe);
+        _ = try deps.add(test_exe);
-            _ = try deps.add(test_exe);
+        const test_run = b.addRunArtifact(test_exe);
-            const test_run = b.addRunArtifact(test_exe);
+        test_step.dependOn(&test_run.step);
-            test_step.dependOn(&test_run.step);
-        }
     }
 
     // update-translations does what it sounds like and updates the "pot"
     // files. These should be committed to the repo.
-    {
+    translations_step.dependOn(i18n.update_step);
-        const step = b.step("update-translations", "Update translation files");
-        step.dependOn(i18n.update_step);
-    }
 }

macos/Ghostty.xcodeproj/project.pbxproj

@@ -303,7 +303,7 @@
 /* End PBXFileReference section */
 
 /* Begin PBXFileSystemSynchronizedRootGroup section */
-		A54F45F42E1F047A0046BD5C /* GhosttyTests */ = {isa = PBXFileSystemSynchronizedRootGroup; explicitFileTypes = {}; explicitFolders = (); path = GhosttyTests; sourceTree = "<group>"; };
+		A54F45F42E1F047A0046BD5C /* Tests */ = {isa = PBXFileSystemSynchronizedRootGroup; explicitFileTypes = {}; explicitFolders = (); path = Tests; sourceTree = "<group>"; };
 /* End PBXFileSystemSynchronizedRootGroup section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -612,7 +612,7 @@
 				A51BFC282B30F26D00E92F16 /* GhosttyDebug.entitlements */,
 				3B39CAA42B33949B00DABEB8 /* GhosttyReleaseLocal.entitlements */,
 				A54CD6ED299BEB14008C95BB /* Sources */,
-				A54F45F42E1F047A0046BD5C /* GhosttyTests */,
+				A54F45F42E1F047A0046BD5C /* Tests */,
 				A5D495A3299BECBA00DD1313 /* Frameworks */,
 				A5A1F8862A489D7400D1E8BC /* Resources */,
 				A5B30532299BEAAA0047F10C /* Products */,
@@ -712,7 +712,7 @@
 				A54F45F82E1F047A0046BD5C /* PBXTargetDependency */,
 			);
 			fileSystemSynchronizedGroups = (
-				A54F45F42E1F047A0046BD5C /* GhosttyTests */,
+				A54F45F42E1F047A0046BD5C /* Tests */,
 			);
 			name = GhosttyTests;
 			packageProductDependencies = (

pkg/harfbuzz/build.zig

@@ -15,15 +15,23 @@ pub fn build(b: *std.Build) !void {
     });
     const macos = b.dependency("macos", .{ .target = target, .optimize = optimize });
 
-    const module = b.addModule("harfbuzz", .{
+    const module = harfbuzz: {
-        .root_source_file = b.path("main.zig"),
+        const module = b.addModule("harfbuzz", .{
-        .target = target,
+            .root_source_file = b.path("main.zig"),
-        .optimize = optimize,
+            .target = target,
-        .imports = &.{
+            .optimize = optimize,
-            .{ .name = "freetype", .module = freetype.module("freetype") },
+            .imports = &.{
-            .{ .name = "macos", .module = macos.module("macos") },
+                .{ .name = "freetype", .module = freetype.module("freetype") },
-        },
+                .{ .name = "macos", .module = macos.module("macos") },
-    });
+            },
+        });
+
+        const options = b.addOptions();
+        options.addOption(bool, "coretext", coretext_enabled);
+        options.addOption(bool, "freetype", freetype_enabled);
+        module.addOptions("build_options", options);
+        break :harfbuzz module;
+    };
 
     // For dynamic linking, we prefer dynamic linking and to search by
     // mode first. Mode first will search all paths for a dynamic library

pkg/harfbuzz/c.zig

@@ -1,7 +1,8 @@
 const builtin = @import("builtin");
+const build_options = @import("build_options");
 
 pub const c = @cImport({
     @cInclude("hb.h");
-    @cInclude("hb-ft.h");
+    if (build_options.freetype) @cInclude("hb-ft.h");
-    if (builtin.os.tag == .macos) @cInclude("hb-coretext.h");
+    if (build_options.coretext) @cInclude("hb-coretext.h");
 });

src/build/GhosttyXcodebuild.zig

@@ -12,6 +12,7 @@ const XCFramework = @import("GhosttyXCFramework.zig");
 build: *std.Build.Step.Run,
 open: *std.Build.Step.Run,
 copy: *std.Build.Step.Run,
+xctest: *std.Build.Step.Run,
 
 pub const Deps = struct {
     xcframework: *const XCFramework,
@@ -33,6 +34,21 @@ pub fn init(
         => "Release",
     };
 
+    const xc_arch: ?[]const u8 = switch (deps.xcframework.target) {
+        // Universal is our default target, so we don't have to
+        // add anything.
+        .universal => null,
+
+        // Native we need to override the architecture in the Xcode
+        // project with the -arch flag.
+        .native => switch (builtin.cpu.arch) {
+            .aarch64 => "arm64",
+            .x86_64 => "x86_64",
+            else => @panic("unsupported macOS arch"),
+        },
+    };
+
+    const env = try std.process.getEnvMap(b.allocator);
     const app_path = b.fmt("macos/build/{s}/Ghostty.app", .{xc_config});
 
     // Our step to build the Ghostty macOS app.
@@ -41,12 +57,13 @@ pub fn init(
         // we create a new empty environment.
         const env_map = try b.allocator.create(std.process.EnvMap);
         env_map.* = .init(b.allocator);
+        if (env.get("PATH")) |v| try env_map.put("PATH", v);
 
-        const build = RunStep.create(b, "xcodebuild");
+        const step = RunStep.create(b, "xcodebuild");
-        build.has_side_effects = true;
+        step.has_side_effects = true;
-        build.cwd = b.path("macos");
+        step.cwd = b.path("macos");
-        build.env_map = env_map;
+        step.env_map = env_map;
-        build.addArgs(&.{
+        step.addArgs(&.{
             "xcodebuild",
             "-target",
             "Ghostty",
@@ -54,36 +71,55 @@ pub fn init(
             xc_config,
         });
 
-        switch (deps.xcframework.target) {
+        // If we have a specific architecture, we need to pass it
-            // Universal is our default target, so we don't have to
+        // to xcodebuild.
-            // add anything.
+        if (xc_arch) |arch| step.addArgs(&.{ "-arch", arch });
-            .universal => {},
-
-            // Native we need to override the architecture in the Xcode
-            // project with the -arch flag.
-            .native => build.addArgs(&.{
-                "-arch",
-                switch (builtin.cpu.arch) {
-                    .aarch64 => "arm64",
-                    .x86_64 => "x86_64",
-                    else => @panic("unsupported macOS arch"),
-                },
-            }),
-        }
 
         // We need the xcframework
-        deps.xcframework.addStepDependencies(&build.step);
+        deps.xcframework.addStepDependencies(&step.step);
 
         // We also need all these resources because the xcode project
         // references them via symlinks.
-        deps.resources.addStepDependencies(&build.step);
+        deps.resources.addStepDependencies(&step.step);
-        deps.i18n.addStepDependencies(&build.step);
+        deps.i18n.addStepDependencies(&step.step);
-        deps.docs.installDummy(&build.step);
+        deps.docs.installDummy(&step.step);
 
         // Expect success
-        build.expectExitCode(0);
+        step.expectExitCode(0);
 
-        break :build build;
+        break :build step;
+    };
+
+    const xctest = xctest: {
+        const env_map = try b.allocator.create(std.process.EnvMap);
+        env_map.* = .init(b.allocator);
+        if (env.get("PATH")) |v| try env_map.put("PATH", v);
+
+        const step = RunStep.create(b, "xcodebuild test");
+        step.has_side_effects = true;
+        step.cwd = b.path("macos");
+        step.env_map = env_map;
+        step.addArgs(&.{
+            "xcodebuild",
+            "test",
+            "-scheme",
+            "Ghostty",
+        });
+        if (xc_arch) |arch| step.addArgs(&.{ "-arch", arch });
+
+        // We need the xcframework
+        deps.xcframework.addStepDependencies(&step.step);
+
+        // We also need all these resources because the xcode project
+        // references them via symlinks.
+        deps.resources.addStepDependencies(&step.step);
+        deps.i18n.addStepDependencies(&step.step);
+        deps.docs.installDummy(&step.step);
+
+        // Expect success
+        step.expectExitCode(0);
+
+        break :xctest step;
     };
 
     // Our step to open the resulting Ghostty app.
@@ -143,6 +179,7 @@ pub fn init(
         .build = build,
         .open = open,
         .copy = copy,
+        .xctest = xctest,
     };
 }
 
@@ -155,3 +192,10 @@ pub fn installXcframework(self: *const Ghostty) void {
     const b = self.build.step.owner;
     b.getInstallStep().dependOn(&self.build.step);
 }
+
+pub fn addTestStepDependencies(
+    self: *const Ghostty,
+    other_step: *std.Build.Step,
+) void {
+    other_step.dependOn(&self.xctest.step);
+}

src/build/SharedDeps.zig

@@ -139,7 +139,7 @@ pub fn add(
         if (b.lazyDependency("harfbuzz", .{
             .target = target,
             .optimize = optimize,
-            .@"enable-freetype" = true,
+            .@"enable-freetype" = self.config.font_backend.hasFreetype(),
             .@"enable-coretext" = self.config.font_backend.hasCoretext(),
         })) |harfbuzz_dep| {
             step.root_module.addImport(