Fill incomplete images in SkCodec parent class

tests/CodexTest.cpp

Index: tests/CodexTest.cpp
diff --git a/tests/CodexTest.cpp b/tests/CodexTest.cpp
index 63631822de45b16c3f3a31bd0406139a7d8b7343..cfdc00341577faf5330ea69564765af34212312c 100644
--- a/tests/CodexTest.cpp
+++ b/tests/CodexTest.cpp
@@ -75,14 +75,15 @@ SkIRect generate_random_subset(SkRandom* rand, int w, int h) {
 }
 
 static void test_codec(skiatest::Reporter* r, SkCodec* codec, SkBitmap& bm, const SkImageInfo& info,
-        const SkISize& size, bool supports565, SkMD5::Digest* digest,
-        const SkMD5::Digest* goodDigest) {
+        const SkISize& size, bool supports565, SkCodec::Result expectedResult,
+        SkMD5::Digest* digest, const SkMD5::Digest* goodDigest) {
+
     REPORTER_ASSERT(r, info.dimensions() == size);
     bm.allocPixels(info);
     SkAutoLockPixels autoLockPixels(bm);
 
     SkCodec::Result result = codec->getPixels(info, bm.getPixels(), bm.rowBytes());
-    REPORTER_ASSERT(r, result == SkCodec::kSuccess);
+    REPORTER_ASSERT(r, result == expectedResult);
 
     md5(bm, digest);
     if (goodDigest) {
@@ -92,16 +93,16 @@ static void test_codec(skiatest::Reporter* r, SkCodec* codec, SkBitmap& bm, cons
     {
         // Test decoding to 565
         SkImageInfo info565 = info.makeColorType(kRGB_565_SkColorType);
-        SkCodec::Result expected = (supports565 && info.alphaType() == kOpaque_SkAlphaType) ?
-                SkCodec::kSuccess : SkCodec::kInvalidConversion;
-        test_info(r, codec, info565, expected, nullptr);
+        SkCodec::Result expected565 = (supports565 && info.alphaType() == kOpaque_SkAlphaType) ?
+                expectedResult : SkCodec::kInvalidConversion;
+        test_info(r, codec, info565, expected565, nullptr);
     }
 
     // Verify that re-decoding gives the same result.  It is interesting to check this after
     // a decode to 565, since choosing to decode to 565 may result in some of the decode
     // options being modified.  These options should return to their defaults on another
     // decode to kN32, so the new digest should match the old digest.
-    test_info(r, codec, info, SkCodec::kSuccess, digest);
+    test_info(r, codec, info, expectedResult, digest);
 
     {
         // Check alpha type conversions
@@ -121,7 +122,7 @@ static void test_codec(skiatest::Reporter* r, SkCodec* codec, SkBitmap& bm, cons
                 otherAt = kPremul_SkAlphaType;
             }
             // The other non-opaque alpha type should always succeed, but not match.
-            test_info(r, codec, info.makeAlphaType(otherAt), SkCodec::kSuccess, nullptr);
+            test_info(r, codec, info.makeAlphaType(otherAt), expectedResult, nullptr);
         }
     }
 }
@@ -131,7 +132,8 @@ static void check(skiatest::Reporter* r,
                   SkISize size,
                   bool supportsScanlineDecoding,
                   bool supportsSubsetDecoding,
-                  bool supports565 = true) {
+                  bool supports565 = true,
+                  bool isIncomplete = false) {
 
     SkAutoTDelete<SkStream> stream(resource(path));
     if (!stream) {
@@ -148,14 +150,15 @@ static void check(skiatest::Reporter* r,
     SkMD5::Digest codecDigest;
     SkImageInfo info = codec->getInfo().makeColorType(kN32_SkColorType);
     SkBitmap bm;
-    test_codec(r, codec, bm, info, size, supports565, &codecDigest, nullptr);
+    SkCodec::Result expectedResult = isIncomplete ? SkCodec::kIncompleteInput : SkCodec::kSuccess;
+    test_codec(r, codec, bm, info, size, supports565, expectedResult, &codecDigest, nullptr);
 
     // Scanline decoding follows.
     // Need to call startScanlineDecode() first.
     REPORTER_ASSERT(r, codec->getScanlines(bm.getAddr(0, 0), 1, 0)
-            == SkCodec::kScanlineDecodingNotStarted);
+            == 0);
     REPORTER_ASSERT(r, codec->skipScanlines(1)
-            == SkCodec::kScanlineDecodingNotStarted);
+            == 0);
 
     const SkCodec::Result startResult = codec->startScanlineDecode(info);
     if (supportsScanlineDecoding) {
@@ -164,8 +167,10 @@ static void check(skiatest::Reporter* r,
         REPORTER_ASSERT(r, startResult == SkCodec::kSuccess);
 
         for (int y = 0; y < info.height(); y++) {
-            SkCodec::Result result = codec->getScanlines(bm.getAddr(0, y), 1, 0);
-            REPORTER_ASSERT(r, result == SkCodec::kSuccess);
+            const uint32_t lines = codec->getScanlines(bm.getAddr(0, y), 1, 0);
+            if (!isIncomplete) {
+                REPORTER_ASSERT(r, 1 == lines);
+            }
         }
         // verify that scanline decoding gives the same result.
         if (SkCodec::kTopDown_SkScanlineOrder == codec->getScanlineOrder()) {
@@ -174,19 +179,19 @@ static void check(skiatest::Reporter* r,
 
         // Cannot continue to decode scanlines beyond the end
         REPORTER_ASSERT(r, codec->getScanlines(bm.getAddr(0, 0), 1, 0)
-                == SkCodec::kInvalidParameters);
+                == 0);
 
         // Interrupting a scanline decode with a full decode starts from
         // scratch
         REPORTER_ASSERT(r, codec->startScanlineDecode(info) == SkCodec::kSuccess);
         REPORTER_ASSERT(r, codec->getScanlines(bm.getAddr(0, 0), 1, 0)
-                == SkCodec::kSuccess);
+                == 1);
         REPORTER_ASSERT(r, codec->getPixels(bm.info(), bm.getPixels(), bm.rowBytes())
-                == SkCodec::kSuccess);
+                == expectedResult);
         REPORTER_ASSERT(r, codec->getScanlines(bm.getAddr(0, 0), 1, 0)
-                == SkCodec::kScanlineDecodingNotStarted);
+                == 0);
         REPORTER_ASSERT(r, codec->skipScanlines(1)
-                == SkCodec::kScanlineDecodingNotStarted);
+                == 0);
     } else {
         REPORTER_ASSERT(r, startResult == SkCodec::kUnimplemented);
     }
@@ -241,7 +246,8 @@ static void check(skiatest::Reporter* r,
 
         SkBitmap bm;
         SkMD5::Digest scaledCodecDigest;
-        test_codec(r, codec, bm, info, size, supports565, &scaledCodecDigest, &codecDigest);
+        test_codec(r, codec, bm, info, size, supports565, expectedResult, &scaledCodecDigest,
+                &codecDigest);
     }
 }
 
@@ -291,6 +297,8 @@ DEF_TEST(Codec, r) {
     check(r, "plane_interlaced.png", SkISize::Make(250, 126), true, false);
     check(r, "randPixels.png", SkISize::Make(8, 8), true, false);
     check(r, "yellow_rose.png", SkISize::Make(400, 301), true, false);
+    // Incomplete Image
+    check(r, "incomplete_images/android.png", SkISize::Make(1024, 1218), true, false, true, true);
 }
 
 // Test interlaced PNG in stripes, similar to DM's kStripe_Mode
@@ -344,12 +352,12 @@ DEF_TEST(Codec_stripes, r) {
     // Odd stripes
     for (int i = 1; i < numStripes; i += 2) {
         // Skip the even stripes
-        result = codec->skipScanlines(stripeHeight);
-        REPORTER_ASSERT(r, result == SkCodec::kSuccess);
+        bool skipResult = codec->skipScanlines(stripeHeight);
+        REPORTER_ASSERT(r, skipResult);
 
-        result = codec->getScanlines(bm.getAddr(0, i * stripeHeight), stripeHeight,
+        int linesDecoded = codec->getScanlines(bm.getAddr(0, i * stripeHeight), stripeHeight,
                                      bm.rowBytes());
-        REPORTER_ASSERT(r, result == SkCodec::kSuccess);
+        REPORTER_ASSERT(r, linesDecoded == stripeHeight);
     }
 
     // Even stripes
@@ -357,14 +365,14 @@ DEF_TEST(Codec_stripes, r) {
     REPORTER_ASSERT(r, result == SkCodec::kSuccess);
 
     for (int i = 0; i < numStripes; i += 2) {
-        result = codec->getScanlines(bm.getAddr(0, i * stripeHeight), stripeHeight,
+        int linesDecoded = codec->getScanlines(bm.getAddr(0, i * stripeHeight), stripeHeight,
                                      bm.rowBytes());
-        REPORTER_ASSERT(r, result == SkCodec::kSuccess);
+        REPORTER_ASSERT(r, linesDecoded == stripeHeight);
 
         // Skip the odd stripes
         if (i + 1 < numStripes) {
-            result = codec->skipScanlines(stripeHeight);
-            REPORTER_ASSERT(r, result == SkCodec::kSuccess);
+            bool skipResult = codec->skipScanlines(stripeHeight);
+            REPORTER_ASSERT(r, skipResult);
         }
     }
 
@@ -373,12 +381,12 @@ DEF_TEST(Codec_stripes, r) {
         result = codec->startScanlineDecode(info);
         REPORTER_ASSERT(r, result == SkCodec::kSuccess);
 
-        result = codec->skipScanlines(height - remainingLines);
-        REPORTER_ASSERT(r, result == SkCodec::kSuccess);
+        bool skipResult = codec->skipScanlines(height - remainingLines);
+        REPORTER_ASSERT(r, skipResult);
 
-        result = codec->getScanlines(bm.getAddr(0, height - remainingLines),
+        int linesDecoded = codec->getScanlines(bm.getAddr(0, height - remainingLines),
                                      remainingLines, bm.rowBytes());
-        REPORTER_ASSERT(r, result == SkCodec::kSuccess);
+        REPORTER_ASSERT(r, linesDecoded == remainingLines);
     }
 
     compare_to_good_digest(r, digest, bm);