dwrite/tests: Some tests for system font set.

dlls/dwrite/tests/font.c

@@ -2291,7 +2291,9 @@ static void test_system_fontcollection(void)
 
     hr = IDWriteFontCollection_QueryInterface(collection, &IID_IDWriteFontCollection1, (void**)&collection1);
     if (hr == S_OK) {
+        IDWriteFontSet *fontset, *fontset2;
         IDWriteFontFamily1 *family1;
+        IDWriteFactory3 *factory3;
 
         hr = IDWriteFontCollection1_QueryInterface(collection1, &IID_IDWriteFontCollection, (void**)&coll2);
         ok(hr == S_OK, "got 0x%08x\n", hr);
@@ -2306,6 +2308,39 @@ static void test_system_fontcollection(void)
         hr = IDWriteFontCollection1_GetFontFamily(collection1, 0, &family1);
         ok(hr == S_OK, "got 0x%08x\n", hr);
         IDWriteFontFamily1_Release(family1);
+
+        /* system fontset */
+        EXPECT_REF(collection1, 2);
+        EXPECT_REF(factory, 2);
+        hr = IDWriteFontCollection1_GetFontSet(collection1, &fontset);
+    todo_wine
+        ok(hr == S_OK, "Failed to get fontset, hr %#x.\n", hr);
+    if (hr == S_OK) {
+        EXPECT_REF(collection1, 2);
+        EXPECT_REF(factory, 2);
+        EXPECT_REF(fontset, 1);
+
+        hr = IDWriteFontCollection1_GetFontSet(collection1, &fontset2);
+        ok(hr == S_OK, "Failed to get fontset, hr %#x.\n", hr);
+        ok(fontset != fontset2, "Expected new fontset instance.\n");
+        EXPECT_REF(fontset2, 1);
+        IDWriteFontSet_Release(fontset2);
+
+        hr = IDWriteFactory_QueryInterface(factory, &IID_IDWriteFactory3, (void **)&factory3);
+        ok(hr == S_OK, "Failed to get IDWriteFactory3 interface, hr %#x.\n", hr);
+
+        EXPECT_REF(factory, 3);
+        hr = IDWriteFactory3_GetSystemFontSet(factory3, &fontset2);
+        ok(hr == S_OK, "Failed to get system font set, hr %#x.\n", hr);
+        ok(fontset != fontset2, "Expected new fontset instance.\n");
+        EXPECT_REF(fontset2, 1);
+        EXPECT_REF(factory, 4);
+
+        IDWriteFontSet_Release(fontset2);
+        IDWriteFontSet_Release(fontset);
+
+        IDWriteFactory3_Release(factory3);
+    }
         IDWriteFontCollection1_Release(collection1);
     }
     else