font group works with deferred faces exclusively

src/Grid.zig

@@ -167,24 +167,24 @@ pub fn init(
         try group.addFace(
             alloc,
             .regular,
-            try font.Face.init(font_lib, face_ttf, font_size),
+            font.DeferredFace.initLoaded(try font.Face.init(font_lib, face_ttf, font_size)),
         );
         try group.addFace(
             alloc,
             .bold,
-            try font.Face.init(font_lib, face_bold_ttf, font_size),
+            font.DeferredFace.initLoaded(try font.Face.init(font_lib, face_bold_ttf, font_size)),
         );
 
         // Emoji
         try group.addFace(
             alloc,
             .regular,
-            try font.Face.init(font_lib, face_emoji_ttf, font_size),
+            font.DeferredFace.initLoaded(try font.Face.init(font_lib, face_emoji_ttf, font_size)),
         );
         try group.addFace(
             alloc,
             .regular,
-            try font.Face.init(font_lib, face_emoji_text_ttf, font_size),
+            font.DeferredFace.initLoaded(try font.Face.init(font_lib, face_emoji_text_ttf, font_size)),
         );
 
         break :group group;

src/font/DeferredFace.zig

@@ -13,6 +13,8 @@ const options = @import("main.zig").options;
 const Face = @import("main.zig").Face;
 const Presentation = @import("main.zig").Presentation;
 
+const Library = @import("main.zig").Library;
+
 /// The loaded face (once loaded).
 face: ?Face = null,
 
@@ -31,6 +33,12 @@ pub const Fontconfig = struct {
     }
 };
 
+/// Initialize a deferred face that is already pre-loaded. The deferred face
+/// takes ownership over the loaded face, deinit will deinit the loaded face.
+pub fn initLoaded(face: Face) DeferredFace {
+    return .{ .face = face };
+}
+
 pub fn deinit(self: *DeferredFace) void {
     if (self.face) |*face| face.deinit();
     if (options.fontconfig) if (self.fc) |*fc| fc.deinit();
@@ -82,3 +90,19 @@ pub fn hasCodepoint(self: DeferredFace, cp: u32, p: ?Presentation) bool {
     // if we're not using a discovery mechanism, the face MUST be loaded.
     unreachable;
 }
+
+test {
+    const testing = std.testing;
+    const testFont = @import("test.zig").fontRegular;
+
+    var lib = try Library.init();
+    defer lib.deinit();
+
+    var face = try Face.init(lib, testFont, .{ .points = 12 });
+    errdefer face.deinit();
+
+    var def = initLoaded(face);
+    defer def.deinit();
+
+    try testing.expect(def.hasCodepoint(' ', null));
+}

src/font/Group.zig

@@ -58,8 +58,8 @@ pub fn deinit(self: *Group, alloc: Allocator) void {
 ///
 /// The group takes ownership of the face. The face will be deallocated when
 /// the group is deallocated.
-pub fn addFace(self: *Group, alloc: Allocator, style: Style, face: Face) !void {
-    try self.faces.getPtr(style).append(alloc, .{ .face = face });
+pub fn addFace(self: *Group, alloc: Allocator, style: Style, face: DeferredFace) !void {
+    try self.faces.getPtr(style).append(alloc, face);
 }
 
 /// This represents a specific font in the group.
@@ -169,9 +169,9 @@ test {
     var group = try init(alloc);
     defer group.deinit(alloc);
 
-    try group.addFace(alloc, .regular, try Face.init(lib, testFont, .{ .points = 12 }));
-    try group.addFace(alloc, .regular, try Face.init(lib, testEmoji, .{ .points = 12 }));
-    try group.addFace(alloc, .regular, try Face.init(lib, testEmojiText, .{ .points = 12 }));
+    try group.addFace(alloc, .regular, DeferredFace.initLoaded(try Face.init(lib, testFont, .{ .points = 12 })));
+    try group.addFace(alloc, .regular, DeferredFace.initLoaded(try Face.init(lib, testEmoji, .{ .points = 12 })));
+    try group.addFace(alloc, .regular, DeferredFace.initLoaded(try Face.init(lib, testEmojiText, .{ .points = 12 })));
 
     // Should find all visible ASCII
     var i: u32 = 32;

src/font/GroupCache.zig

@@ -7,6 +7,7 @@ const Allocator = std.mem.Allocator;
 
 const Atlas = @import("../Atlas.zig");
 const Face = @import("main.zig").Face;
+const DeferredFace = @import("main.zig").DeferredFace;
 const Library = @import("main.zig").Library;
 const Glyph = @import("main.zig").Glyph;
 const Style = @import("main.zig").Style;
@@ -221,7 +222,11 @@ test {
     defer cache.deinit(alloc);
 
     // Setup group
-    try cache.group.addFace(alloc, .regular, try Face.init(lib, testFont, .{ .points = 12 }));
+    try cache.group.addFace(
+        alloc,
+        .regular,
+        DeferredFace.initLoaded(try Face.init(lib, testFont, .{ .points = 12 })),
+    );
     const group = cache.group;
 
     // Visible ASCII. Do it twice to verify cache.

src/font/Shaper.zig

@@ -8,6 +8,7 @@ const harfbuzz = @import("harfbuzz");
 const trace = @import("tracy").trace;
 const Atlas = @import("../Atlas.zig");
 const Face = @import("main.zig").Face;
+const DeferredFace = @import("main.zig").DeferredFace;
 const Group = @import("main.zig").Group;
 const GroupCache = @import("main.zig").GroupCache;
 const Library = @import("main.zig").Library;
@@ -599,9 +600,9 @@ fn testShaper(alloc: Allocator) !TestShaper {
     errdefer cache_ptr.*.deinit(alloc);
 
     // Setup group
-    try cache_ptr.group.addFace(alloc, .regular, try Face.init(lib, testFont, .{ .points = 12 }));
-    try cache_ptr.group.addFace(alloc, .regular, try Face.init(lib, testEmoji, .{ .points = 12 }));
-    try cache_ptr.group.addFace(alloc, .regular, try Face.init(lib, testEmojiText, .{ .points = 12 }));
+    try cache_ptr.group.addFace(alloc, .regular, DeferredFace.initLoaded(try Face.init(lib, testFont, .{ .points = 12 })));
+    try cache_ptr.group.addFace(alloc, .regular, DeferredFace.initLoaded(try Face.init(lib, testEmoji, .{ .points = 12 })));
+    try cache_ptr.group.addFace(alloc, .regular, DeferredFace.initLoaded(try Face.init(lib, testEmojiText, .{ .points = 12 })));
 
     var cell_buf = try alloc.alloc(Cell, 80);
     errdefer alloc.free(cell_buf);