config: window-inherit-working-directory options

`window-inherit-working-directory` was previously a boolean value. This
change makes it a more granular option, allowing you to enable this
behavior for one or more surface "kinds": split, tab, window.

The configuration value can be `true` (all), `false` (none), or a
comma-delimited string of kinds (e.g. `tab` or `split,window`).

The full behavior is only implemented for the embedded runtime and macOS
app. The other runtimes still need their own plumbing to track surface
kind creation (stubbed as `.window` by default in this change).

include/ghostty.h

@@ -31,6 +31,12 @@ typedef void* ghostty_surface_t;
 typedef void* ghostty_inspector_t;
 
 // Enums are up top so we can reference them later.
+typedef enum {
+  GHOSTTY_SURFACE_KIND_SPLIT,
+  GHOSTTY_SURFACE_KIND_TAB,
+  GHOSTTY_SURFACE_KIND_WINDOW,
+} ghostty_surface_kind_e;
+
 typedef enum {
   GHOSTTY_PLATFORM_INVALID,
   GHOSTTY_PLATFORM_MACOS,
@@ -395,6 +401,7 @@ typedef union {
 } ghostty_platform_u;
 
 typedef struct {
+  ghostty_surface_kind_e kind;
   ghostty_platform_e platform_tag;
   ghostty_platform_u platform;
   void* userdata;

macos/Sources/Ghostty/SurfaceView.swift

@@ -291,6 +291,8 @@ extension Ghostty {
     /// The configuration for a surface. For any configuration not set, defaults will be chosen from
     /// libghostty, usually from the Ghostty configuration.
     struct SurfaceConfiguration {
+        var kind: ghostty_surface_kind_e? = nil;
+
         /// Explicit font size to use in points
         var fontSize: Float32? = nil
         
@@ -303,6 +305,7 @@ extension Ghostty {
         init() {}
         
         init(from config: ghostty_surface_config_s) {
+            self.kind = config.kind;
             self.fontSize = config.font_size
             self.workingDirectory = String.init(cString: config.working_directory, encoding: .utf8)
             self.command = String.init(cString: config.command, encoding: .utf8)
@@ -334,6 +337,7 @@ extension Ghostty {
             #error("unsupported target")
             #endif
             
+            if let kind = kind { config.kind = kind }
             if let fontSize = fontSize { config.font_size = fontSize }
             if let workingDirectory = workingDirectory {
                 config.working_directory = (workingDirectory as NSString).utf8String

src/Surface.zig

@@ -125,6 +125,13 @@ config: DerivedConfig,
 /// This is used to determine if we need to confirm, hold open, etc.
 child_exited: bool = false,
 
+/// The kind of surface.
+pub const Kind = enum(c_int) {
+    split,
+    tab,
+    window,
+};
+
 /// The effect of an input event. This can be used by callers to take
 /// the appropriate action after an input event. For example, key
 /// input can be forwarded to the OS for further processing if it

src/apprt/embedded.zig

@@ -308,6 +308,9 @@ pub const Surface = struct {
 
     /// Surface initialization options.
     pub const Options = extern struct {
+        /// The initial kind of surface.
+        kind: CoreSurface.Kind = .window,
+
         /// The platform that this surface is being initialized for and
         /// the associated platform-specific configuration.
         platform_tag: c_int = 0,
@@ -365,7 +368,7 @@ pub const Surface = struct {
         errdefer app.core_app.deleteSurface(self);
 
         // Shallow copy the config so that we can modify it.
-        var config = try apprt.surface.newConfig(app.core_app, app.config);
+        var config = try apprt.surface.newConfig(app.core_app, app.config, opts.kind);
         defer config.deinit();
 
         // If we have a working directory from the options then we set it.
@@ -473,7 +476,7 @@ pub const Surface = struct {
             return;
         };
 
-        const options = self.newSurfaceOptions();
+        const options = self.newSurfaceOptions(.split);
         func(self.userdata, direction, options);
     }
 
@@ -1024,7 +1027,7 @@ pub const Surface = struct {
             return;
         };
 
-        const options = self.newSurfaceOptions();
+        const options = self.newSurfaceOptions(.tab);
         func(self.userdata, options);
     }
 
@@ -1034,7 +1037,7 @@ pub const Surface = struct {
             return;
         };
 
-        const options = self.newSurfaceOptions();
+        const options = self.newSurfaceOptions(.window);
         func(self.userdata, options);
     }
 
@@ -1065,13 +1068,14 @@ pub const Surface = struct {
         func(self.userdata, width, height);
     }
 
-    fn newSurfaceOptions(self: *const Surface) apprt.Surface.Options {
+    fn newSurfaceOptions(self: *const Surface, kind: CoreSurface.Kind) apprt.Surface.Options {
         const font_size: f32 = font_size: {
             if (!self.app.config.@"window-inherit-font-size") break :font_size 0;
             break :font_size self.core_surface.font_size.points;
         };
 
         return .{
+            .kind = kind,
             .font_size = font_size,
         };
     }

src/apprt/glfw.zig

@@ -448,7 +448,8 @@ pub const Surface = struct {
         errdefer app.app.deleteSurface(self);
 
         // Get our new surface config
-        var config = try apprt.surface.newConfig(app.app, &app.config);
+        const kind: CoreSurface.Kind = .window; // TODO
+        var config = try apprt.surface.newConfig(app.app, &app.config, kind);
         defer config.deinit();
 
         // Initialize our surface now that we have the stable pointer.

src/apprt/gtk/Surface.zig

@@ -543,7 +543,8 @@ fn realize(self: *Surface) !void {
     errdefer self.app.core_app.deleteSurface(self);
 
     // Get our new surface config
-    var config = try apprt.surface.newConfig(self.app.core_app, &self.app.config);
+    const kind: CoreSurface.Kind = .window; // TODO
+    var config = try apprt.surface.newConfig(self.app.core_app, &self.app.config, kind);
     defer config.deinit();
     if (!self.parent_surface) {
         // A hack, see the "parent_surface" field for more information.

src/apprt/surface.zig

@@ -1,3 +1,4 @@
+const std = @import("std");
 const apprt = @import("../apprt.zig");
 const App = @import("../App.zig");
 const Surface = @import("../Surface.zig");
@@ -85,7 +86,7 @@ pub const Mailbox = struct {
 /// Returns a new config for a surface for the given app that should be
 /// used for any new surfaces. The resulting config should be deinitialized
 /// after the surface is initialized.
-pub fn newConfig(app: *const App, config: *const Config) !Config {
+pub fn newConfig(app: *const App, config: *const Config, kind: Surface.Kind) !Config {
     // Create a shallow clone
     var copy = config.shallowClone(app.alloc);
 
@@ -95,7 +96,12 @@ pub fn newConfig(app: *const App, config: *const Config) !Config {
     // Get our previously focused surface for some inherited values.
     const prev = app.focusedSurface();
     if (prev) |p| {
-        if (config.@"window-inherit-working-directory") {
+        const inherit_pwd: bool = switch (kind) {
+            .split => config.@"window-inherit-working-directory".split,
+            .tab => config.@"window-inherit-working-directory".tab,
+            .window => config.@"window-inherit-working-directory".window,
+        };
+        if (inherit_pwd) {
             if (try p.pwd(alloc)) |pwd| {
                 copy.@"working-directory" = pwd;
             }

src/config.zig

@@ -20,6 +20,7 @@ pub const RepeatableCodepointMap = Config.RepeatableCodepointMap;
 pub const RepeatableFontVariation = Config.RepeatableFontVariation;
 pub const RepeatableString = Config.RepeatableString;
 pub const ShellIntegrationFeatures = Config.ShellIntegrationFeatures;
+pub const WindowInheritWorkingDirectory = Config.WindowInheritWorkingDirectory;
 
 // Alternate APIs
 pub const CAPI = @import("config/CAPI.zig");

src/config/Config.zig

@@ -33,6 +33,9 @@ const help_strings = @import("help_strings");
 
 const log = std.log.scoped(.config);
 
+// For trimming
+const whitespace = " \t";
+
 /// Used on Unixes for some defaults.
 const c = @cImport({
     @cInclude("unistd.h");
@@ -679,10 +682,15 @@ keybind: Keybinds = .{},
 /// This setting is only supported currently on macOS.
 @"window-vsync": bool = true,
 
-/// If true, new windows and tabs will inherit the working directory of the
-/// previously focused window. If no window was previously focused, the default
-/// working directory will be used (the `working-directory` option).
-@"window-inherit-working-directory": bool = true,
+/// Controls whether new splits, tabs, and windows will inherit the working
+/// directory of the previously focused window. If no window was previously
+/// focused, the default working directory will be used (the `working-directory`
+/// option).
+///
+/// Value value are `split`, `tab`, and `window`. You can specify multiple
+/// values using a comma-delimited string (`tab` or `split,window`). You
+/// can also set this to `true` (always inherit) or `false` (never inherit).
+@"window-inherit-working-directory": WindowInheritWorkingDirectory = .{},
 
 /// If true, new windows and tabs will inherit the font size of the previously
 /// focused window. If no window was previously focused, the default font size
@@ -2956,7 +2964,6 @@ pub const RepeatableFontVariation = struct {
     pub fn parseCLI(self: *Self, alloc: Allocator, input_: ?[]const u8) !void {
         const input = input_ orelse return error.ValueRequired;
         const eql_idx = std.mem.indexOf(u8, input, "=") orelse return error.InvalidValue;
-        const whitespace = " \t";
         const key = std.mem.trim(u8, input[0..eql_idx], whitespace);
         const value = std.mem.trim(u8, input[eql_idx + 1 ..], whitespace);
         if (key.len != 4) return error.InvalidValue;
@@ -3219,7 +3226,6 @@ pub const RepeatableCodepointMap = struct {
     pub fn parseCLI(self: *Self, alloc: Allocator, input_: ?[]const u8) !void {
         const input = input_ orelse return error.ValueRequired;
         const eql_idx = std.mem.indexOf(u8, input, "=") orelse return error.InvalidValue;
-        const whitespace = " \t";
         const key = std.mem.trim(u8, input[0..eql_idx], whitespace);
         const value = std.mem.trim(u8, input[eql_idx + 1 ..], whitespace);
         const valueZ = try alloc.dupeZ(u8, value);
@@ -3740,6 +3746,70 @@ pub const WindowNewTabPosition = enum {
     end,
 };
 
+/// Options for inheriting the working directory of the previous window.
+pub const WindowInheritWorkingDirectory = packed struct {
+    const Self = @This();
+
+    split: bool = false,
+    tab: bool = false,
+    window: bool = false,
+
+    pub fn parseCLI(self: *Self, _: Allocator, input: ?[]const u8) !void {
+        const value = input orelse return error.ValueRequired;
+        const fields = @typeInfo(Self).Struct.fields;
+
+        if (std.mem.eql(u8, value, "true")) {
+            self.* = .{ .split = true, .tab = true, .window = true };
+            return;
+        }
+
+        if (std.mem.eql(u8, value, "false")) {
+            self.* = .{ .split = false, .tab = false, .window = false };
+            return;
+        }
+
+        // Enable all of the fields named in the comma-separated value.
+        self.* = .{};
+        var iter = std.mem.splitSequence(u8, value, ",");
+        loop: while (iter.next()) |part_raw| {
+            const part = std.mem.trim(u8, part_raw, whitespace);
+
+            inline for (fields) |field| {
+                assert(field.type == bool);
+                if (std.mem.eql(u8, field.name, part)) {
+                    @field(self, field.name) = true;
+                    continue :loop;
+                }
+            }
+
+            // No field matched
+            return error.InvalidValue;
+        }
+    }
+
+    test "parseCLI" {
+        const testing = std.testing;
+        var arena = ArenaAllocator.init(testing.allocator);
+        defer arena.deinit();
+        const alloc = arena.allocator();
+
+        var p: Self = .{};
+        try p.parseCLI(alloc, "true");
+        try testing.expectEqual(Self{ .split = true, .tab = true, .window = true }, p);
+
+        try p.parseCLI(alloc, "false");
+        try testing.expectEqual(Self{ .split = false, .tab = false, .window = false }, p);
+
+        try p.parseCLI(alloc, "tab");
+        try testing.expectEqual(Self{ .split = false, .tab = true, .window = false }, p);
+
+        try p.parseCLI(alloc, "split,window");
+        try testing.expectEqual(Self{ .split = true, .tab = false, .window = true }, p);
+
+        try testing.expectError(error.InvalidValue, p.parseCLI(alloc, "unknown"));
+    }
+};
+
 /// See grapheme-width-method
 pub const GraphemeWidthMethod = enum {
     legacy,