Repo created

libs/coding/coding_tests/reader_cache_test.cpp

@@ -0,0 +1,49 @@
+#include "testing/testing.hpp"
+
+#include "coding/reader.hpp"
+#include "coding/reader_cache.hpp"
+
+#include <algorithm>
+#include <random>
+#include <string>
+#include <vector>
+
+using namespace std;
+
+namespace
+{
+template <class ReaderT>
+class CacheReader
+{
+public:
+  CacheReader(ReaderT const & reader, uint32_t logPageSize, uint32_t logPageCount)
+    : m_Reader(reader)
+    , m_Cache(logPageSize, logPageCount)
+  {}
+
+  void Read(uint64_t pos, void * p, size_t size) const { m_Cache.Read(m_Reader, pos, p, size); }
+
+private:
+  ReaderT m_Reader;
+  ReaderCache<ReaderT const> mutable m_Cache;
+};
+}  // namespace
+
+UNIT_TEST(CacheReaderRandomTest)
+{
+  vector<char> data(100000);
+  for (size_t i = 0; i < data.size(); ++i)
+    data[i] = static_cast<char>(i % 253);
+  MemReader memReader(&data[0], data.size());
+  CacheReader<MemReader> cacheReader(MemReader(&data[0], data.size()), 10, 5);
+  mt19937 rng(0);
+  for (size_t i = 0; i < 100000; ++i)
+  {
+    size_t pos = rng() % data.size();
+    size_t len = min(static_cast<size_t>(1 + (rng() % 127)), data.size() - pos);
+    string readMem(len, '0'), readCache(len, '0');
+    memReader.Read(pos, &readMem[0], len);
+    cacheReader.Read(pos, &readCache[0], len);
+    TEST_EQUAL(readMem, readCache, (pos, len, i));
+  }
+}