[Impeller] Fixed GlyphAtlasWithLotsOfdUniqueGlyphSize (#42423)

fixes flutter/flutter#127715

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Author: gaaclarke

impeller/typographer/typographer_unittests.cc

@@ -165,18 +165,20 @@ TEST_P(TypographerTest, GlyphAtlasWithLotsOfdUniqueGlyphSize) {
   ASSERT_TRUE(context && context->IsValid());
   SkFont sk_font;
 
-  auto blob = SkTextBlob::MakeFromString(
+  const char* test_string =
       "QWERTYUIOPASDFGHJKLZXCVBNMqewrtyuiopasdfghjklzxcvbnm,.<>[]{};':"
       "2134567890-=!@#$%^&*()_+"
       "œ∑´®†¥¨ˆøπ““‘‘åß∂ƒ©˙∆˚¬…æ≈ç√∫˜µ≤≥≥≥≥÷¡™£¢∞§¶•ªº–≠⁄€‹›fifl‡°·‚—±Œ„´‰Á¨Ø∏”’/"
-      "* Í˝ */¸˛Ç◊ı˜Â¯˘¿",
-      sk_font);
+      "* Í˝ */¸˛Ç◊ı˜Â¯˘¿";
+
+  auto blob = SkTextBlob::MakeFromString(test_string, sk_font);
   ASSERT_TRUE(blob);
 
   TextFrame frame;
   size_t count = 0;
+  const int size_count = 8;
   TextRenderContext::FrameIterator iterator = [&]() -> const TextFrame* {
-    if (count < 8) {
+    if (count < size_count) {
       count++;
       frame = TextFrameFromTextBlob(blob, 0.6 * count);
       return &frame;
@@ -188,8 +190,20 @@ TEST_P(TypographerTest, GlyphAtlasWithLotsOfdUniqueGlyphSize) {
   ASSERT_NE(atlas, nullptr);
   ASSERT_NE(atlas->GetTexture(), nullptr);
 
-  ASSERT_EQ(atlas->GetTexture()->GetSize().width * 2,
-            atlas->GetTexture()->GetSize().height);
+  std::set<uint16_t> unique_glyphs;
+  std::vector<uint16_t> total_glyphs;
+  atlas->IterateGlyphs([&](const FontGlyphPair& pair, const Rect& rect) {
+    unique_glyphs.insert(pair.glyph.index);
+    total_glyphs.push_back(pair.glyph.index);
+    return true;
+  });
+
+  EXPECT_EQ(unique_glyphs.size() * size_count, atlas->GetGlyphCount());
+  EXPECT_EQ(total_glyphs.size(), atlas->GetGlyphCount());
+
+  EXPECT_TRUE(atlas->GetGlyphCount() > 0);
+  EXPECT_TRUE(atlas->GetTexture()->GetSize().width > 0);
+  EXPECT_TRUE(atlas->GetTexture()->GetSize().height > 0);
 }
 
 TEST_P(TypographerTest, GlyphAtlasTextureIsRecycledIfUnchanged) {

testing/run_tests.py

@@ -1201,12 +1201,10 @@ def main():
           'impeller_unittests',
           engine_filter,
           # TODO(https://github.com/flutter/flutter/issues/127714): Remove test exemption.
-          # TODO(https://github.com/flutter/flutter/issues/127715): Remove test exemption.
           shuffle_flags + [
               '--gtest_filter=-'
               '*/OpenGLES:'
               'Play/TypographerTest.MaybeHasOverlapping/Vulkan:'
-              'Play/TypographerTest.GlyphAtlasWithLotsOfdUniqueGlyphSize/Vulkan',
           ],
           coverage=args.coverage
       )