ArduinoJson/test/DynamicMemoryPool/blocks.cpp

// ArduinoJson - arduinojson.org
// Copyright Benoit Blanchon 2014-2018
// MIT License

#include <ArduinoJson/Memory/DynamicMemoryPool.hpp>
#include <catch.hpp>
#include <sstream>

using namespace ARDUINOJSON_NAMESPACE;

std::stringstream allocatorLog;

struct SpyingAllocator : DefaultAllocator {
  void* allocate(size_t n) {
    allocatorLog << "A" << (n - DynamicMemoryPool::EmptyBlockSize);
    return DefaultAllocator::allocate(n);
  }
  void deallocate(void* p) {
    allocatorLog << "F";
    return DefaultAllocator::deallocate(p);
  }
};

TEST_CASE("DynamicMemoryPool blocks") {
  SECTION("Doubles allocation size when full") {
    allocatorLog.str("");
    {
      DynamicMemoryPoolBase<SpyingAllocator> memoryPool(sizeof(VariantSlot));
      memoryPool.allocVariant();
      memoryPool.allocVariant();
    }
    std::stringstream expected;
    expected << "A" << sizeof(VariantSlot)      // block 1
             << "A" << 2 * sizeof(VariantSlot)  // block 2, twice bigger
             << "FF";

    REQUIRE(allocatorLog.str() == expected.str());
  }

  SECTION("Resets allocation size after clear()") {
    allocatorLog.str("");
    {
      DynamicMemoryPoolBase<SpyingAllocator> memoryPool(sizeof(VariantSlot));
      memoryPool.allocVariant();
      memoryPool.allocVariant();
      memoryPool.clear();
      memoryPool.allocVariant();
    }
    std::stringstream expected;
    expected << "A" << sizeof(VariantSlot)      // block 1
             << "A" << 2 * sizeof(VariantSlot)  // block 2, twice bigger
             << "FF"                            // clear
             << "A" << sizeof(VariantSlot)      // block 1
             << "F";
    REQUIRE(allocatorLog.str() == expected.str());
  }

  /* SECTION("Alloc big block for large string") {
     allocatorLog.str("");
     {
       DynamicMemoryPoolBase<SpyingAllocator> memoryPool(1);
       memoryPool.allocString(42);
     }
     std::stringstream expected;
     expected << "A" << JSON_STRING_SIZE(42)  // block 1
              << "F";
     REQUIRE(allocatorLog.str() == expected.str());
   }*/
}