Removed the automatic expansion of DynamicJsonDocument

test/MemoryPool/CMakeLists.txt

@@ -0,0 +1,14 @@
+# ArduinoJson - arduinojson.org
+# Copyright Benoit Blanchon 2014-2018
+# MIT License
+
+add_executable(MemoryPoolTests 
+	allocVariant.cpp
+	allocString.cpp
+	clear.cpp
+	size.cpp
+	StringBuilder.cpp
+)
+
+target_link_libraries(MemoryPoolTests catch)
+add_test(MemoryPool MemoryPoolTests)

test/MemoryPool/StringBuilder.cpp

@@ -0,0 +1,41 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#include <ArduinoJson/Memory/MemoryPool.hpp>
+#include <ArduinoJson/Memory/StringBuilder.hpp>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+static char buffer[4096];
+
+TEST_CASE("StringBuilder") {
+  SECTION("Works when buffer is big enough") {
+    MemoryPool memoryPool(buffer, addPadding(JSON_STRING_SIZE(6)));
+
+    StringBuilder str(&memoryPool);
+    str.append("hello");
+
+    REQUIRE(str.complete().equals("hello"));
+  }
+
+  SECTION("Returns null when too small") {
+    MemoryPool memoryPool(buffer, sizeof(void*));
+
+    StringBuilder str(&memoryPool);
+    str.append("hello world!");
+
+    REQUIRE(str.complete().isNull());
+  }
+
+  SECTION("Increases size of memory pool") {
+    MemoryPool memoryPool(buffer, addPadding(JSON_STRING_SIZE(6)));
+
+    StringBuilder str(&memoryPool);
+    str.append('h');
+    str.complete();
+
+    REQUIRE(JSON_STRING_SIZE(2) == memoryPool.size());
+  }
+}

test/MemoryPool/allocString.cpp

@@ -0,0 +1,143 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#include <ArduinoJson/Memory/MemoryPool.hpp>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+TEST_CASE("MemoryPool::allocFrozenString()") {
+  const size_t poolCapacity = 64;
+  const size_t longestString = poolCapacity - sizeof(StringSlot);
+  char buffer[poolCapacity];
+  MemoryPool pool(buffer, poolCapacity);
+
+  SECTION("Returns different addresses") {
+    StringSlot *a = pool.allocFrozenString(1);
+    StringSlot *b = pool.allocFrozenString(1);
+    REQUIRE(a != b);
+    REQUIRE(a->value != b->value);
+  }
+
+  SECTION("Returns a StringSlot of the right size") {
+    StringSlot *s = pool.allocFrozenString(12);
+    REQUIRE(s->size == 12);
+  }
+
+  SECTION("Returns NULL when full") {
+    pool.allocFrozenString(longestString);
+    void *p = pool.allocFrozenString(1);
+    REQUIRE(0 == p);
+  }
+
+  SECTION("Returns NULL when pool is too small") {
+    void *p = pool.allocFrozenString(longestString + 1);
+    REQUIRE(0 == p);
+  }
+
+  SECTION("Returns NULL when buffer is NULL") {
+    MemoryPool pool2(0, poolCapacity);
+    REQUIRE(0 == pool2.allocFrozenString(2));
+  }
+
+  SECTION("Returns NULL when capacity is 0") {
+    MemoryPool pool2(buffer, 0);
+    REQUIRE(0 == pool2.allocFrozenString(2));
+  }
+
+  SECTION("Returns aligned pointers") {
+    REQUIRE(isAligned(pool.allocFrozenString(1)));
+    REQUIRE(isAligned(pool.allocFrozenString(1)));
+  }
+
+  SECTION("Returns same address after clear()") {
+    StringSlot *a = pool.allocFrozenString(1);
+    pool.clear();
+    StringSlot *b = pool.allocFrozenString(1);
+
+    REQUIRE(a == b);
+    REQUIRE(a->value == b->value);
+  }
+
+  SECTION("Returns same address after freeString()") {
+    StringSlot *a = pool.allocFrozenString(1);
+    pool.freeString(a);
+    StringSlot *b = pool.allocFrozenString(1);
+
+    REQUIRE(a == b);
+    REQUIRE(a->value == b->value);
+  }
+
+  SECTION("Can use full capacity when fresh") {
+    StringSlot *a = pool.allocFrozenString(longestString);
+
+    REQUIRE(a != 0);
+  }
+
+  SECTION("Can use full capacity after clear") {
+    pool.allocFrozenString(longestString);
+    pool.clear();
+
+    StringSlot *a = pool.allocFrozenString(longestString);
+
+    REQUIRE(a != 0);
+  }
+}
+
+TEST_CASE("MemoryPool::freeString()") {
+  const size_t poolCapacity = 512;
+  const size_t longestString = poolCapacity - sizeof(StringSlot);
+  char buffer[poolCapacity];
+  MemoryPool pool(buffer, poolCapacity);
+
+  static const size_t testStringSize =
+      (poolCapacity - sizeof(StringSlot) * 4 - sizeof(VariantSlot) * 4) / 4;
+
+  SECTION("Restores full capacity") {
+    StringSlot *strings[4];
+    VariantSlot *variants[4];
+
+    for (int i = 0; i < 4; i++) {
+      strings[i] = pool.allocFrozenString(testStringSize);
+      REQUIRE(strings[i] != 0);
+      variants[i] = pool.allocVariant();
+      REQUIRE(variants[i] != 0);
+    }
+
+    // In random order
+    pool.freeString(strings[2]);
+    pool.freeVariant(variants[3]);
+    pool.freeVariant(variants[0]);
+    pool.freeString(strings[0]);
+    pool.freeVariant(variants[1]);
+    pool.freeString(strings[1]);
+    pool.freeVariant(variants[2]);
+    pool.freeString(strings[3]);
+
+    StringSlot *b = pool.allocFrozenString(longestString);
+
+    REQUIRE(b != 0);
+    REQUIRE(b->size == longestString);
+  }
+
+  SECTION("Move strings") {
+    StringSlot *a = pool.allocFrozenString(6);
+    strcpy(a->value, "hello");
+
+    StringSlot *b = pool.allocFrozenString(7);
+    strcpy(b->value, "world!");
+    pool.freeString(a);
+
+    REQUIRE(b->size == 7);
+    REQUIRE(b->value == std::string("world!"));
+    REQUIRE(a->value == b->value);
+  }
+
+  SECTION("Accepts non-frozen string") {
+    StringSlot *a = pool.allocExpandableString();
+    pool.freeString(a);
+
+    REQUIRE(pool.size() == 0);
+  }
+}

test/MemoryPool/allocVariant.cpp

@@ -0,0 +1,60 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#include <ArduinoJson/Memory/MemoryPool.hpp>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+static char buffer[4096];
+
+TEST_CASE("MemoryPool::allocVariant()") {
+  SECTION("Returns different pointer") {
+    MemoryPool pool(buffer, sizeof(buffer));
+
+    VariantSlot* s1 = pool.allocVariant();
+    REQUIRE(s1 != 0);
+    VariantSlot* s2 = pool.allocVariant();
+    REQUIRE(s2 != 0);
+
+    REQUIRE(s1 != s2);
+  }
+
+  SECTION("Returns same pointer after freeSlot()") {
+    MemoryPool pool(buffer, sizeof(buffer));
+
+    VariantSlot* s1 = pool.allocVariant();
+    pool.freeVariant(s1);
+    VariantSlot* s2 = pool.allocVariant();
+
+    REQUIRE(s1 == s2);
+  }
+
+  SECTION("Returns aligned pointers") {
+    MemoryPool pool(buffer, sizeof(buffer));
+
+    REQUIRE(isAligned(pool.allocVariant()));
+    REQUIRE(isAligned(pool.allocVariant()));
+  }
+
+  SECTION("Returns zero if capacity is 0") {
+    MemoryPool pool(buffer, 0);
+
+    REQUIRE(pool.allocVariant() == 0);
+  }
+
+  SECTION("Returns zero if buffer is null") {
+    MemoryPool pool(0, sizeof(buffer));
+
+    REQUIRE(pool.allocVariant() == 0);
+  }
+
+  SECTION("Returns zero if capacity is insufficient") {
+    MemoryPool pool(buffer, sizeof(VariantSlot));
+
+    pool.allocVariant();
+
+    REQUIRE(pool.allocVariant() == 0);
+  }
+}

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"));
+  }
+}

test/MemoryPool/size.cpp

@@ -0,0 +1,93 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#include <ArduinoJson/Memory/MemoryPool.hpp>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+char buffer[4096];
+
+TEST_CASE("MemoryPool::capacity()") {
+  const size_t capacity = 64;
+  MemoryPool memoryPool(buffer, capacity);
+  REQUIRE(capacity == memoryPool.capacity());
+}
+
+TEST_CASE("MemoryPool::size()") {
+  MemoryPool memoryPool(buffer, sizeof(buffer));
+
+  SECTION("Initial size is 0") {
+    REQUIRE(0 == memoryPool.size());
+  }
+
+  SECTION("size() == capacity() after allocExpandableString()") {
+    memoryPool.allocExpandableString();
+    REQUIRE(memoryPool.size() == memoryPool.capacity());
+  }
+
+  SECTION("Decreases after freezeString()") {
+    StringSlot* a = memoryPool.allocExpandableString();
+    memoryPool.freezeString(a, 1);
+    REQUIRE(memoryPool.size() == JSON_STRING_SIZE(1));
+
+    StringSlot* b = memoryPool.allocExpandableString();
+    memoryPool.freezeString(b, 1);
+    REQUIRE(memoryPool.size() == 2 * JSON_STRING_SIZE(1));
+  }
+
+  SECTION("Increases after allocFrozenString()") {
+    memoryPool.allocFrozenString(0);
+    REQUIRE(memoryPool.size() == JSON_STRING_SIZE(0));
+
+    memoryPool.allocFrozenString(0);
+    REQUIRE(memoryPool.size() == 2 * JSON_STRING_SIZE(0));
+  }
+
+  SECTION("Decreases after freeVariant()") {
+    VariantSlot* a = memoryPool.allocVariant();
+    VariantSlot* b = memoryPool.allocVariant();
+
+    memoryPool.freeVariant(b);
+    REQUIRE(memoryPool.size() == sizeof(VariantSlot));
+
+    memoryPool.freeVariant(a);
+    REQUIRE(memoryPool.size() == 0);
+  }
+
+  SECTION("Decreases after calling freeString() in order") {
+    StringSlot* a = memoryPool.allocFrozenString(5);
+    REQUIRE(a != 0);
+    StringSlot* b = memoryPool.allocFrozenString(6);
+    REQUIRE(b != 0);
+
+    memoryPool.freeString(b);
+    REQUIRE(memoryPool.size() == JSON_STRING_SIZE(5));
+    memoryPool.freeString(a);
+    REQUIRE(memoryPool.size() == 0);
+  }
+
+  SECTION("Decreases after calling freeString() in reverse order") {
+    StringSlot* a = memoryPool.allocFrozenString(5);
+    REQUIRE(a != 0);
+    StringSlot* b = memoryPool.allocFrozenString(6);
+    REQUIRE(b != 0);
+
+    memoryPool.freeString(a);
+    REQUIRE(memoryPool.size() == JSON_STRING_SIZE(6));
+    memoryPool.freeString(b);
+    REQUIRE(memoryPool.size() == 0);
+  }
+
+  SECTION("Doesn't grow when memory pool is full") {
+    const size_t variantCount = sizeof(buffer) / sizeof(VariantSlot);
+
+    for (size_t i = 0; i < variantCount; i++) memoryPool.allocVariant();
+    size_t size = memoryPool.size();
+
+    memoryPool.allocVariant();
+
+    REQUIRE(size == memoryPool.size());
+  }
+}