[core] harden Glyph PBF parsing

1 files changed, 71 insertions, 0 deletions

diff --git a/test/text/glyph_pbf.test.cpp b/test/text/glyph_pbf.test.cpp
new file mode 100644
index 0000000000..1e28dfbc31
--- /dev/null
+++ b/test/text/glyph_pbf.test.cpp
@@ -0,0 +1,71 @@
+#include <mbgl/test/util.hpp>
+
+#include <mbgl/text/glyph_set.hpp>
+#include <mbgl/text/glyph_atlas_observer.hpp>
+#include <mbgl/text/glyph_atlas.hpp>
+#include <mbgl/text/glyph_pbf.hpp>
+#include <mbgl/storage/default_file_source.hpp>
+#include <mbgl/util/run_loop.hpp>
+#include <mbgl/util/string.hpp>
+
+#include <future>
+
+using namespace mbgl;
+
+using namespace std::string_literals;
+
+class MockGlyphAtlasObserver : public GlyphAtlasObserver {
+public:
+    std::function<void(const FontStack&, const GlyphRange&)> glyphsLoaded;
+    std::function<void(const FontStack&, const GlyphRange&, std::exception_ptr)> glyphsError;
+
+    void onGlyphsLoaded(const FontStack& fontStack, const GlyphRange& glyphRange) override {
+        if (glyphsLoaded) {
+            glyphsLoaded(fontStack, glyphRange);
+        }
+    }
+    void onGlyphsError(const FontStack& fontStack, const GlyphRange& glyphRange, std::exception_ptr error) override {
+        if (glyphsError) {
+            glyphsError(fontStack, glyphRange, error);
+        }
+    }
+};
+
+TEST(GlyphPBF, Parsing) {
+    util::RunLoop loop;
+    DefaultFileSource fileSource{ ":memory:", "." };
+    GlyphAtlas glyphAtlas{ { 1024, 1024 }, fileSource };
+    FontStack fontStack{ "fake_glyphs" };
+    GlyphRange glyphRange{ 0, 255 };
+
+    glyphAtlas.setURL("asset://test/fixtures/resources/{fontstack}-{range}.pbf");
+
+    MockGlyphAtlasObserver glyphAtlasObserver;
+    glyphAtlasObserver.glyphsLoaded = [&](const FontStack&, const GlyphRange&) {
+        loop.stop();
+
+        auto sdfs = glyphAtlas.getGlyphSet(fontStack)->getSDFs();
+
+        // The fake glyphs don't contain a glyph that has the ID 0; it only contains glyphs with
+        // undefined IDs, but the parser should remove them.
+
+        EXPECT_TRUE(sdfs.size() == 1);
+        EXPECT_TRUE(sdfs.find(69) != sdfs.end());
+        auto& sdf = sdfs[69];
+        EXPECT_EQ("xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"s, sdf.bitmap);
+        EXPECT_EQ(1u, sdf.metrics.width);
+        EXPECT_EQ(1u, sdf.metrics.height);
+        EXPECT_EQ(20, sdf.metrics.left);
+        EXPECT_EQ(2, sdf.metrics.top);
+        EXPECT_EQ(8u, sdf.metrics.advance);
+    };
+
+    glyphAtlasObserver.glyphsError = [&](const FontStack&, const GlyphRange&, std::exception_ptr error) {
+        loop.stop();
+        FAIL() << util::toString(error);
+    };
+
+    GlyphPBF pbf(&glyphAtlas, fontStack, glyphRange, &glyphAtlasObserver, fileSource);
+
+    loop.run();
+}