Image filter DAG test for makeColorSpace()

Change-Id: I8aa3a8c701fdfe215cae639bc9c7082340c756d4
Reviewed-on: https://skia-review.googlesource.com/21721
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>

1 files changed, 46 insertions, 0 deletions

diff --git a/tests/ImageFilterTest.cpp b/tests/ImageFilterTest.cpp
index f8435868c4..c6d184dfea 100644
--- a/tests/ImageFilterTest.cpp
+++ b/tests/ImageFilterTest.cpp
@@ -10,6 +10,7 @@
 #include "SkCanvas.h"
 #include "SkColorFilterImageFilter.h"
 #include "SkColorMatrixFilter.h"
+#include "SkColorSpaceXformer.h"
 #include "SkComposeImageFilter.h"
 #include "SkDisplacementMapEffect.h"
 #include "SkDropShadowImageFilter.h"
@@ -1877,3 +1878,48 @@ DEF_TEST(ImageFilterComplexCTM, reporter) {
         REPORTER_ASSERT(reporter, canHandle == rec.fExpectCanHandle);
     }
 }
+
+// Test that transforming the filter DAG doesn't clone shared nodes multiple times.
+DEF_TEST(ImageFilterColorSpaceDAG, reporter) {
+
+    // Helper for counting makeColorSpace() clones.
+    class TestFilter final : public SkImageFilter {
+    public:
+        TestFilter() : INHERITED(nullptr, 0, nullptr) {}
+
+#ifndef SK_IGNORE_TO_STRING
+        void toString(SkString*) const override {}
+#endif
+        Factory getFactory() const override { return nullptr; }
+
+        size_t cloneCount() const { return fCloneCount; }
+
+    protected:
+        sk_sp<SkSpecialImage> onFilterImage(SkSpecialImage* src, const Context&,
+                                            SkIPoint* offset) const override {
+            return nullptr;
+        }
+        sk_sp<SkImageFilter> onMakeColorSpace(SkColorSpaceXformer*) const override {
+            fCloneCount++;
+            return sk_ref_sp(const_cast<TestFilter*>(this));
+        }
+
+    private:
+        typedef SkImageFilter INHERITED;
+
+        mutable size_t fCloneCount = 0;
+    };
+
+    auto filter = sk_make_sp<TestFilter>();
+    REPORTER_ASSERT(reporter, filter->cloneCount() == 0u);
+
+    // Build a DAG referencing the filter twice.
+    auto complexFilter = SkMergeImageFilter::Make(filter, SkOffsetImageFilter::Make(1, 1, filter));
+    REPORTER_ASSERT(reporter, filter->cloneCount() == 0u);
+
+    auto xformer = SkColorSpaceXformer::Make(SkColorSpace::MakeSRGB());
+    auto xformedFilter = xformer->apply(complexFilter.get());
+
+    // FIXME: clone count should be 1 at this point.
+    REPORTER_ASSERT(reporter, filter->cloneCount() == 2u);
+}