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+++ b/mobile/android/tests/background/junit4/src/org/mozilla/gecko/icons/processing/TestMinimumSizeProcessor.java
@@ -0,0 +1,85 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+package org.mozilla.gecko.icons.processing;
+
+import android.graphics.Bitmap;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mozilla.gecko.background.testhelpers.TestRunner;
+import org.mozilla.gecko.icons.IconRequest;
+import org.mozilla.gecko.icons.IconResponse;
+import org.robolectric.RuntimeEnvironment;
+
+import static org.mockito.Mockito.*;
+
+@RunWith(TestRunner.class)
+public class TestMinimumSizeProcessor {
+
+    private MinimumSizeProcessor processor;
+
+    @Before
+    public void setUp() {
+        processor = new MinimumSizeProcessor();
+    }
+
+    @Test
+    public void testProcessMinimumSizeZeroDoesNotReplaceSmallBitmap() throws Exception {
+        final IconResponse responseMock = getMockResponse(1);
+        processor.process(getMockRequest(0), responseMock);
+
+        verify(responseMock, never()).updateBitmap(any(Bitmap.class));
+        verify(responseMock, never()).updateColor(anyInt());
+    }
+
+    @Test
+    public void testProcessMinimumSizeZeroDoesNotReplaceLargeBitmap() throws Exception {
+        final IconResponse responseMock = getMockResponse(1000);
+        processor.process(getMockRequest(0), responseMock);
+
+        verify(responseMock, never()).updateBitmap(any(Bitmap.class));
+        verify(responseMock, never()).updateColor(anyInt());
+    }
+
+    @Test
+    public void testProcessMinimumSizeFiftyReplacesSmallerBitmap() throws Exception {
+        final IconResponse responseMock = getMockResponse(25);
+        processor.process(getMockRequest(50), responseMock);
+
+        verify(responseMock, atLeastOnce()).updateBitmap(any(Bitmap.class));
+        verify(responseMock, atLeastOnce()).updateColor(anyInt());
+    }
+
+    @Test
+    public void testProcessMinimumSizeFiftyDoesNotReplaceLargerBitmap() throws Exception {
+        final IconResponse responseMock = getMockResponse(1000);
+        processor.process(getMockRequest(50), responseMock);
+
+        verify(responseMock, never()).updateBitmap(any(Bitmap.class));
+        verify(responseMock, never()).updateColor(anyInt());
+    }
+
+    private IconRequest getMockRequest(final int minimumSizePx) {
+        final IconRequest requestMock = mock(IconRequest.class);
+
+        // Under testing.
+        when(requestMock.getMinimumSizePxAfterScaling()).thenReturn(minimumSizePx);
+
+        // Happened to be called.
+        when(requestMock.getPageUrl()).thenReturn("https://mozilla.org");
+        when(requestMock.getContext()).thenReturn(RuntimeEnvironment.application);
+        return requestMock;
+    }
+
+    private IconResponse getMockResponse(final int bitmapWidth) {
+        final Bitmap bitmapMock = mock(Bitmap.class);
+        when(bitmapMock.getWidth()).thenReturn(bitmapWidth);
+        when(bitmapMock.getHeight()).thenReturn(bitmapWidth); // not strictly necessary with the current impl.
+
+        final IconResponse responseMock = mock(IconResponse.class);
+        when(responseMock.getBitmap()).thenReturn(bitmapMock);
+        return responseMock;
+    }
+}
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