apprt/gtk-ng: abstract helper for private string fields

src/apprt/gtk-ng/class.zig

@@ -46,6 +46,48 @@ pub fn Common(
             }
         }).private else {};
 
+        /// A helper that can be used to create a property that reads and
+        /// writes a private `?[:0]const u8` field type.
+        ///
+        /// This helper helps properly manage the memory to avoid memory leaks.
+        ///
+        /// The object class (Self) must still free the private field
+        /// in finalize!
+        pub fn privateStringFieldAccessor(
+            comptime name: []const u8,
+        ) gobject.ext.Accessor(
+            Self,
+            @FieldType(Private.?, name),
+        ) {
+            const S = struct {
+                fn getter(self: *Self) ?[:0]const u8 {
+                    return @field(private(self), name);
+                }
+
+                fn setter(self: *Self, value: ?[:0]const u8) void {
+                    const priv = private(self);
+                    if (@field(priv, name)) |v| {
+                        glib.free(@constCast(@ptrCast(v)));
+                    }
+
+                    // We don't need to copy this because it was already
+                    // copied by the typedAccessor.
+                    @field(priv, name) = value;
+                }
+            };
+
+            return gobject.ext.typedAccessor(
+                Self,
+                ?[:0]const u8,
+                .{
+                    .getter = S.getter,
+                    .getter_transfer = .none,
+                    .setter = S.setter,
+                    .setter_transfer = .full,
+                },
+            );
+        }
+
         /// Common class functions.
         pub const Class = struct {
             pub fn as(class: *Self.Class, comptime T: type) *T {

src/apprt/gtk-ng/class/surface.zig

@@ -96,6 +96,8 @@ pub const Surface = extern struct {
 
         pub const pwd = struct {
             pub const name = "pwd";
+            pub const get = impl.get;
+            pub const set = impl.set;
             const impl = gobject.ext.defineProperty(
                 name,
                 Self,
@@ -104,22 +106,15 @@ pub const Surface = extern struct {
                     .nick = "Working Directory",
                     .blurb = "The current working directory as reported by core.",
                     .default = null,
-                    .accessor = gobject.ext.typedAccessor(
+                    .accessor = C.privateStringFieldAccessor("pwd"),
-                        Self,
-                        ?[:0]const u8,
-                        .{
-                            .getter = getPwd,
-                            .getter_transfer = .none,
-                            .setter = setPwd,
-                            .setter_transfer = .full,
-                        },
-                    ),
                 },
             );
         };
 
         pub const title = struct {
             pub const name = "title";
+            pub const get = impl.get;
+            pub const set = impl.set;
             const impl = gobject.ext.defineProperty(
                 name,
                 Self,
@@ -128,16 +123,7 @@ pub const Surface = extern struct {
                     .nick = "Title",
                     .blurb = "The title of the surface.",
                     .default = null,
-                    .accessor = gobject.ext.typedAccessor(
+                    .accessor = C.privateStringFieldAccessor("title"),
-                        Self,
-                        ?[:0]const u8,
-                        .{
-                            .getter = getTitle,
-                            .getter_transfer = .none,
-                            .setter = setTitle,
-                            .setter_transfer = .full,
-                        },
-                    ),
                 },
             );
         };
@@ -876,8 +862,10 @@ pub const Surface = extern struct {
 
             priv.core_surface = null;
         }
-        if (priv.pwd != null) self.setPwd(null);
+
-        if (priv.title != null) self.setTitle(null);
+        var @"null": gobject.Value = undefined;
+        if (priv.pwd != null) properties.pwd.set(self, &@"null");
+        if (priv.title != null) properties.pwd.set(self, &@"null");
 
         gobject.Object.virtual_methods.finalize.call(
             Class.parent,
@@ -888,41 +876,6 @@ pub const Surface = extern struct {
     //---------------------------------------------------------------
     // Properties
 
-    fn getPwd(
-        self: *Self,
-    ) ?[:0]const u8 {
-        return self.private().pwd;
-    }
-
-    fn setPwd(
-        self: *Self,
-        value: ?[:0]const u8,
-    ) void {
-        const priv = self.private();
-
-        // Free the previous value
-        if (priv.pwd) |v| glib.free(@constCast(@ptrCast(v.ptr)));
-
-        // Set the new value, which is already copied since we
-        // set our setter_transfer value to full.
-        priv.pwd = value;
-    }
-
-    fn getTitle(
-        self: *Self,
-    ) ?[:0]const u8 {
-        return self.private().title;
-    }
-
-    fn setTitle(
-        self: *Self,
-        value: ?[:0]const u8,
-    ) void {
-        const priv = self.private();
-        if (priv.title) |v| glib.free(@constCast(@ptrCast(v.ptr)));
-        priv.title = value;
-    }
-
     fn propMouseHidden(
         self: *Self,
         _: *gobject.ParamSpec,