Font subset (#14828)

Author: dnfield

BUILD.gn

@@ -31,6 +31,10 @@ group("flutter") {
     "$flutter_root/sky",
   ]
 
+  if (current_toolchain == host_toolchain) {
+    public_deps += [ "$flutter_root/tools/font-subset" ]
+  }
+
   if (current_toolchain == host_toolchain) {
     public_deps += [ "$flutter_root/shell/testing" ]
   }

testing/run_tests.py

@@ -20,6 +20,7 @@
 fonts_dir = os.path.join(buildroot_dir, 'flutter', 'third_party', 'txt', 'third_party', 'fonts')
 roboto_font_path = os.path.join(fonts_dir, 'Roboto-Regular.ttf')
 dart_tests_dir = os.path.join(buildroot_dir, 'flutter', 'testing', 'dart',)
+font_subset_dir = os.path.join(buildroot_dir, 'flutter', 'tools', 'font-subset')
 
 fml_unittests_filter = '--gtest_filter=-*TimeSensitiveTest*:*GpuThreadMerger*'
 
@@ -326,7 +327,7 @@ def main():
   args = parser.parse_args()
 
   if args.type == 'all':
-    types = ['engine', 'dart', 'benchmarks', 'java']
+    types = ['engine', 'dart', 'benchmarks', 'java', 'font-subset']
   else:
     types = args.type.split(',')
 
@@ -355,6 +356,9 @@ def main():
   if 'benchmarks' in types and not IsWindows():
     RunEngineBenchmarks(build_dir, engine_filter)
 
+  if 'engine' in types or 'font-subset' in types:
+    RunCmd(['python', 'test.py'], cwd=font_subset_dir)
+
 
 if __name__ == '__main__':
   sys.exit(main())

tools/font-subset/.gitignore

@@ -0,0 +1 @@
+gen/*.ttf

tools/font-subset/BUILD.gn

@@ -0,0 +1,23 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+executable("font-subset") {
+  sources = [
+    "hb_wrappers.h",
+    "main.cc",
+  ]
+
+  deps = [
+    "//third_party/harfbuzz",
+  ]
+
+  libs = []
+  if (is_mac) {
+    libs += [
+      "Foundation.framework",
+      "CoreGraphics.framework",
+      "CoreText.framework",
+    ]
+  }
+}

tools/font-subset/fixtures/1.ttf

@@ -0,0 +1,35 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef HB_WRAPPERS_H_
+#define HB_WRAPPERS_H_
+
+#include <hb-subset.h>
+
+namespace HarfbuzzWrappers {
+struct hb_blob_deleter {
+  void operator()(hb_blob_t* ptr) { hb_blob_destroy(ptr); }
+};
+
+struct hb_face_deleter {
+  void operator()(hb_face_t* ptr) { hb_face_destroy(ptr); }
+};
+
+struct hb_subset_input_deleter {
+  void operator()(hb_subset_input_t* ptr) { hb_subset_input_destroy(ptr); }
+};
+
+struct hb_set_deleter {
+  void operator()(hb_set_t* ptr) { hb_set_destroy(ptr); }
+};
+
+using HbBlobPtr = std::unique_ptr<hb_blob_t, hb_blob_deleter>;
+using HbFacePtr = std::unique_ptr<hb_face_t, hb_face_deleter>;
+using HbSubsetInputPtr =
+    std::unique_ptr<hb_subset_input_t, hb_subset_input_deleter>;
+using HbSetPtr = std::unique_ptr<hb_set_t, hb_set_deleter>;
+
+};  // namespace HarfbuzzWrappers
+
+#endif  // HB_WRAPPERS_H_s