Append terminator in saveStringFromFreeZone()

extras/tests/JsonDeserializer/string.cpp

@@ -113,3 +113,21 @@ TEST_CASE("Not enough room to save the key") {
             DeserializationError::NoMemory);  // fails in the second string
   }
 }
+
+TEST_CASE("Empty memory pool") {
+  // NOLINTNEXTLINE(clang-analyzer-optin.portability.UnixAPI)
+  DynamicJsonDocument doc(0);
+
+  SECTION("Input is const char*") {
+    REQUIRE(deserializeJson(doc, "\"hello\"") ==
+            DeserializationError::NoMemory);
+    REQUIRE(deserializeJson(doc, "\"\"") == DeserializationError::NoMemory);
+  }
+
+  SECTION("Input is const char*") {
+    char hello[] = "\"hello\"";
+    REQUIRE(deserializeJson(doc, hello) == DeserializationError::Ok);
+    char empty[] = "\"hello\"";
+    REQUIRE(deserializeJson(doc, empty) == DeserializationError::Ok);
+  }
+}

extras/tests/MemoryPool/StringCopier.cpp

@@ -11,12 +11,11 @@ TEST_CASE("StringCopier") {
   char buffer[4096];
 
   SECTION("Works when buffer is big enough") {
-    MemoryPool pool(buffer, addPadding(JSON_STRING_SIZE(6)));
+    MemoryPool pool(buffer, addPadding(JSON_STRING_SIZE(5)));
     StringCopier str(pool);
 
     str.startString();
     str.append("hello");
-    str.append('\0');
 
     REQUIRE(str.isValid() == true);
     REQUIRE(std::string(str.str()) == "hello");
@@ -31,6 +30,7 @@ TEST_CASE("StringCopier") {
     str.append("hello world!");
 
     REQUIRE(str.isValid() == false);
+    REQUIRE(pool.overflowed() == true);
   }
 
   SECTION("Increases size of memory pool") {
@@ -38,10 +38,19 @@ TEST_CASE("StringCopier") {
     StringCopier str(pool);
 
     str.startString();
-    str.append('h');
     str.save();
 
     REQUIRE(1 == pool.size());
+    REQUIRE(pool.overflowed() == false);
+  }
+
+  SECTION("Works when memory pool is 0 bytes") {
+    MemoryPool pool(buffer, 0);
+    StringCopier str(pool);
+
+    str.startString();
+    REQUIRE(str.isValid() == false);
+    REQUIRE(pool.overflowed() == true);
   }
 }
 
@@ -49,7 +58,6 @@ static const char* addStringToPool(MemoryPool& pool, const char* s) {
   StringCopier str(pool);
   str.startString();
   str.append(s);
-  str.append('\0');
   return str.save().c_str();
 }
 

extras/tests/Misc/Utf8.cpp

@@ -18,7 +18,6 @@ static void testCodepoint(uint32_t codepoint, std::string expected) {
   CAPTURE(codepoint);
   Utf8::encodeCodepoint(codepoint, str);
 
-  str.append('\0');
   REQUIRE(str.str().c_str() == expected);
 }
 

extras/tests/Misc/printable.cpp

@@ -60,6 +60,7 @@ TEST_CASE("Printable") {
       CHECK(printable.totalBytesWritten() == 7);
       CHECK(doc.overflowed() == false);
       CHECK(doc.memoryUsage() == 8);
+      CHECK(doc.as<JsonVariant>().memoryUsage() == 8);
     }
 
     SECTION("Via Print::write(const char* size_t)") {
@@ -69,6 +70,7 @@ TEST_CASE("Printable") {
       CHECK(printable.totalBytesWritten() == 7);
       CHECK(doc.overflowed() == false);
       CHECK(doc.memoryUsage() == 8);
+      CHECK(doc.as<JsonVariant>().memoryUsage() == 8);
     }
   }