Override SkCanvas::drawImage() in SkRecorder.

tests/RecorderTest.cpp

Index: tests/RecorderTest.cpp
diff --git a/tests/RecorderTest.cpp b/tests/RecorderTest.cpp
index aced54f7a906fa32c56ffc5ee25ad8b10fd8fd1f..9339bcd2d6cb80d8fc4ce16bf70154dec8ed34e6 100644
--- a/tests/RecorderTest.cpp
+++ b/tests/RecorderTest.cpp
@@ -12,6 +12,7 @@
 #include "SkRecorder.h"
 #include "SkRecords.h"
 #include "SkShader.h"
+#include "SkSurface.h"
 
 #define COUNT(T) + 1
 static const int kRecordTypes = SK_RECORD_TYPES(COUNT);
@@ -150,3 +151,29 @@ DEF_TEST(Recorder_IsDrawingToLayer, r) {
     REPORTER_ASSERT(r, !recorder.isDrawingToLayer());
 }
 
+DEF_TEST(Recorder_drawImage_takeReference, reporter) {
+
+    SkAutoTUnref<SkSurface> surface(SkSurface::NewRasterPMColor(100, 100));
+    surface->getCanvas()->clear(SK_ColorGREEN);
+    SkAutoTUnref<SkImage> image(surface->newImageSnapshot());
+    int beginImageRefCount = image->getRefCnt();

[mtklein, 2014/09/27 15:41:22]

We generally try to avoid calling getRefCnt().  Here in this test it's safe, but
it's a bad habit to get into (because unless it returns 1, it wasn't thread-safe
to call).

I'd prefer it if you can write your test using unique(), if only to use the less
powerful tool when possible:

Maybe like this?

<setup>
REPORTER_ASSERT(r, image->unique());
{
    SkRecord record;
    SkRecorder recorder(&record, ...); 
    recorder.drawImage(image, ...);
    REPORTER_ASSERT(r, !image->unique());  
    Tally tally;
    tally.apply(record);
    REPORTER_ASSERT(r, 1 == tally.count<SkRecords::DrawImage>());
}
REPORTER_ASSERT(r, image->unique());
{
    SkRecord record;
    SkRecorder recorder(&record, ...);
    recorder.drawImageRect(image, ...);
    REPORTER_ASSERT(r, !image->unique());
    Tally tally;
    tally.apply(record);
    REPORTER_ASSERT(r, 1 == tally.count<SkRecords::DrawImageRect>());
}
REPORTER_ASSERT(r, image->unique());

[Rémi Piotaix, 2014/09/29 17:57:55]

Done.

+    {
+        SkRecord record;
+        SkRecorder recorder(&record, 100, 100);
+
+        // DrawImage is supposed to take a reference
+        recorder.drawImage(image.get(), 0, 0);
+        REPORTER_ASSERT(reporter, image->getRefCnt() == beginImageRefCount + 1);
+
+        recorder.drawImageRect(image.get(), 0, SkRect::MakeWH(100, 100));
+        REPORTER_ASSERT(reporter, image->getRefCnt() == beginImageRefCount + 2);
+
+        Tally tally;
+        tally.apply(record);
+
+        REPORTER_ASSERT(reporter, 1 == tally.count<SkRecords::DrawImage>());
+        REPORTER_ASSERT(reporter, 1 == tally.count<SkRecords::DrawImageRect>());
+    }
+    // The SkImage should have the same refCnt as before
+    REPORTER_ASSERT(reporter, image->getRefCnt() == beginImageRefCount);
+}