Flate Test tests if compression works
- Produce a compressable stream.
- Assert compression ratio > 1
- In verbose mode, print compression ratio.
R=mtklein@google.com
Author: halcanary@google.com
Review URL: https://codereview.chromium.org/464373002
diff --git a/tests/FlateTest.cpp b/tests/FlateTest.cpp
index a49ff5f..3e8e583 100644
--- a/tests/FlateTest.cpp
+++ b/tests/FlateTest.cpp
@@ -7,7 +7,6 @@
#include "SkData.h"
#include "SkFlate.h"
-#include "SkRandom.h"
#include "SkStream.h"
#include "Test.h"
@@ -26,12 +25,12 @@
static const size_t kGetSizeKey = 0xDEADBEEF;
};
-// Returns a deterministic data of the given size.
+// Returns a deterministic data of the given size that should be
+// very compressible.
static SkData* new_test_data(size_t dataSize) {
SkAutoTMalloc<uint8_t> testBuffer(dataSize);
- SkRandom random(0);
for (size_t i = 0; i < dataSize; ++i) {
- testBuffer[i] = random.nextU() & 0xFF;
+ testBuffer[i] = i % 64;
}
return SkData::NewFromMalloc(testBuffer.detach(), dataSize);
}
@@ -60,12 +59,7 @@
dataSize) == 0);
}
- // Assume there are two test sizes, big and small.
- if (dataSize < 1024) {
- REPORTER_ASSERT(reporter, compressed.getOffset() < 1024);
- } else {
- REPORTER_ASSERT(reporter, compressed.getOffset() > 1024);
- }
+ size_t compressedSize = compressed.getOffset();
SkAutoDataUnref compressedData(compressed.copyToData());
testStream->setData(compressedData.get());
@@ -79,7 +73,7 @@
if (inputSize == 0) {
inputSize = testStream->read(NULL, SkZeroSizeMemStream::kGetSizeKey);
}
- REPORTER_ASSERT(reporter, compressedData->size() == inputSize);
+ REPORTER_ASSERT(reporter, compressedSize == inputSize);
if (compressedData->size() == inputSize) {
REPORTER_ASSERT(reporter, memcmp(testStream->getMemoryBase(),
compressedData->data(),
@@ -94,6 +88,17 @@
uncompressedData->data(),
dataSize) == 0);
}
+
+ double compressionRatio = static_cast<double>(dataSize) / compressedSize;
+ // Assert that some compression took place.
+ REPORTER_ASSERT(reporter, compressionRatio > 1.2);
+
+ if (reporter->verbose()) {
+ SkDebugf("Flate Test: \t input size: " SK_SIZE_T_SPECIFIER
+ "\tcompressed size: " SK_SIZE_T_SPECIFIER
+ "\tratio: %.4g\n",
+ dataSize, compressedSize, compressionRatio);
+ }
}
DEF_TEST(Flate, reporter) {