Added a deprecation warning for as<char>() and set(char)

extras/tests/Misc/deprecated.cpp

@@ -11,23 +11,65 @@ TEST_CASE("Deprecated features") {
   StaticJsonDocument<256> doc;
   const char* s = "hello";
   doc["s"] = s;
+  doc["c"] = 42;
   doc["a"].add(s);
+  doc["a"].add(42);
+
+  SECTION("JsonVariant::add(char)") {
+    JsonVariant v = doc.to<JsonVariant>();
+    v.add('*');
+    REQUIRE(v[0] == 42);
+  }
 
   SECTION("JsonVariant::as<char*>()") {
     JsonVariant v = doc["s"];
     REQUIRE(v.as<char*>() == s);
   }
 
+  SECTION("JsonVariant::as<char>()") {
+    JsonVariant v = doc["c"];
+    REQUIRE(v.as<char>() == '*');
+  }
+
+  SECTION("JsonVariant::set(char)") {
+    JsonVariant v = doc.to<JsonVariant>();
+    v.set('*');
+    REQUIRE(v.as<unsigned char>() == 42);
+  }
+
   SECTION("JsonVariantConst::as<char*>()") {
     JsonVariantConst v = doc["s"];
     REQUIRE(v.as<char*>() == s);
   }
 
+  SECTION("JsonVariantConst::as<char>()") {
+    JsonVariantConst v = doc["c"];
+    REQUIRE(v.as<char>() == '*');
+  }
+
   SECTION("MemberProxy::as<char*>()") {
     REQUIRE(doc["s"].as<char*>() == s);
   }
 
+  SECTION("MemberProxy::as<char>()") {
+    REQUIRE(doc["c"].as<char>() == '*');
+  }
+
+  SECTION("MemberProxy::as<char>()") {
+    doc["x"].set('*');
+    REQUIRE(doc["x"] == 42);
+  }
+
   SECTION("ElementProxy::as<char*>()") {
     REQUIRE(doc["a"][0].as<char*>() == s);
   }
+
+  SECTION("ElementProxy::as<char>()") {
+    REQUIRE(doc["a"][1].as<char>() == '*');
+  }
+
+  SECTION("ElementProxy::as<char>()") {
+    doc["a"][0].set('*');
+    REQUIRE(doc["a"][0] == 42);
+  }
 }