Removed the automatic expansion of DynamicJsonDocument

test/MemoryPool/clear.cpp

@@ -0,0 +1,83 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#include <ArduinoJson/Memory/MemoryPool.hpp>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+static const size_t poolCapacity = 512;
+
+TEST_CASE("MemoryPool::clear()") {
+  char buffer[poolCapacity];
+  MemoryPool memoryPool(buffer, sizeof(buffer));
+
+  SECTION("Discards allocated variants") {
+    memoryPool.allocVariant();
+
+    memoryPool.clear();
+    REQUIRE(memoryPool.size() == 0);
+  }
+
+  SECTION("Discards allocated strings") {
+    memoryPool.allocFrozenString(10);
+    REQUIRE(memoryPool.size() > 0);
+
+    memoryPool.clear();
+
+    REQUIRE(memoryPool.size() == 0);
+  }
+
+  SECTION("Purges variant cache") {
+    VariantSlot* a = memoryPool.allocVariant();
+    REQUIRE(a != 0);
+    VariantSlot* b = memoryPool.allocVariant();
+    REQUIRE(b != 0);
+
+    // place slot a in the pool of free slots
+    memoryPool.freeVariant(a);
+    memoryPool.clear();
+
+    REQUIRE(memoryPool.size() == 0);
+  }
+
+  SECTION("Purges string cache") {
+    StringSlot* a = memoryPool.allocFrozenString(10);
+    REQUIRE(a != 0);
+    StringSlot* b = memoryPool.allocFrozenString(10);
+    REQUIRE(b != 0);
+
+    // place slot a in the pool of free slots
+    memoryPool.freeString(a);
+    memoryPool.clear();
+
+    REQUIRE(memoryPool.size() == 0);
+  }
+
+  SECTION("Purges list of string") {
+    StringSlot* a = memoryPool.allocFrozenString(6);
+    REQUIRE(a != 0);
+    strcpy(a->value, "hello");
+
+    StringSlot* b = memoryPool.allocFrozenString(6);
+    REQUIRE(b != 0);
+    strcpy(b->value, "world");
+
+    memoryPool.clear();  // ACT!
+
+    StringSlot* c = memoryPool.allocFrozenString(2);
+    REQUIRE(c != 0);
+    strcpy(c->value, "H");
+
+    StringSlot* d = memoryPool.allocFrozenString(2);
+    REQUIRE(d != 0);
+    strcpy(d->value, "W");
+
+    // if the memory pool keeps pointer to the old strings
+    // it will try to compact the strings
+    memoryPool.freeString(c);
+
+    REQUIRE(d->value == std::string("W"));
+  }
+}