Fix a bunch of preserve-type issues:

- Issue 205
- Issue 294
- Issue 318

gson/src/main/java/com/google/gson/DefaultTypeAdapters.java

@@ -677,7 +677,8 @@ final class DefaultTypeAdapters {
         } else {
           Type childType = (childGenericType == null || childGenericType == Object.class)
               ? child.getClass() : childGenericType;
-          JsonElement element = context.serialize(child, childType);
+          JsonSerializationContextDefault contextImpl = (JsonSerializationContextDefault) context;
+          JsonElement element = contextImpl.serialize(child, childType, false);
           array.add(element);
         }
       }

gson/src/main/java/com/google/gson/JsonSerializationContextDefault.java

@@ -16,7 +16,6 @@
 
 package com.google.gson;
 
-
 import java.lang.reflect.Type;
 
 /**
@@ -59,7 +58,8 @@ final class JsonSerializationContextDefault implements JsonSerializationContext
     }
     JsonSerializationVisitor visitor = new JsonSerializationVisitor(
         objectNavigator, fieldNamingPolicy, serializeNulls, serializers, this, ancestors);
-    objectNavigator.accept(new ObjectTypePair(src, typeOfSrc, preserveType), visitor);
+    ObjectTypePair objTypePair = new ObjectTypePair(src, typeOfSrc, preserveType);
+    objectNavigator.accept(objTypePair, visitor);
     return visitor.getJsonElement();
   }
-}
+}

gson/src/main/java/com/google/gson/ObjectNavigator.java

@@ -100,6 +100,7 @@ final class ObjectNavigator {
     }
     boolean visitedWithCustomHandler = visitor.visitUsingCustomHandler(objTypePair);
     if (!visitedWithCustomHandler) {
+      objTypePair = objTypePair.toMoreSpecificType();
       Object obj = objTypePair.getObject();
       Object objectToVisit = (obj == null) ? visitor.getTarget() : obj;
       if (objectToVisit == null) {
@@ -108,7 +109,7 @@ final class ObjectNavigator {
       objTypePair.setObject(objectToVisit);
       visitor.start(objTypePair);
       try {
-        if ($Gson$Types.isArray(objTypePair.type)) {
+        if ($Gson$Types.isArray(objTypePair.getMoreSpecificType())) {
           visitor.visitArray(objectToVisit, objTypePair.type);
         } else if (objTypePair.type == Object.class && isPrimitiveOrString(objectToVisit)) {
           // TODO(Joel): this is only used for deserialization of "primitives"

gson/src/main/java/com/google/gson/ObjectTypePair.java

@@ -75,7 +75,7 @@ final class ObjectTypePair {
     if (actualType == type) {
       return this;
     }
-    return new ObjectTypePair(obj, actualType, preserveType);
+    return new ObjectTypePair(obj, actualType, true);
   }
 
   Type getMoreSpecificType() {

gson/src/test/java/com/google/gson/functional/ArrayTest.java

@@ -274,6 +274,14 @@ public class ArrayTest extends TestCase {
     assertEquals("[[1,2]]", gson.toJson(array));
   }
 
+  /**
+   * Regression test for Issue 205
+   */
+  public void testMixingTypesInObjectArraySerialization() {
+    Object[] array = new Object[] { 1, 2, new Object[] { "one", "two" } };
+    assertEquals("[1,2,[\"one\",\"two\"]]", gson.toJson(array));
+  }
+
   /**
    * Regression tests for Issue 272
    */

gson/src/test/java/com/google/gson/functional/MapTest.java

@@ -421,6 +421,22 @@ public class MapTest extends TestCase {
     assertEquals(expected, json);
   }
 
+  public void testGeneralMapField() throws Exception {
+    MapWithGeneralMapParameters map = new MapWithGeneralMapParameters();
+    map.map.put("string", "testString");
+    map.map.put("stringArray", new String[] { "one", "two" });
+    map.map.put("objectArray", new Object[] { 1, 2L, "three" });
+
+    String expected = "{\"map\":{\"string\":\"testString\",\"stringArray\":"
+        + "[\"one\",\"two\"],\"objectArray\":[1,2,\"three\"]}}";
+    assertEquals(expected, gson.toJson(map));
+
+    gson = new GsonBuilder()
+        .enableComplexMapKeySerialization()
+        .create();
+    assertEquals(expected, gson.toJson(map));
+  }
+
   static final class MapClass {
     private final Map<String, TestTypes.Base> bases = new HashMap<String, TestTypes.Base>();
     private final Map<String, TestTypes.Sub> subs = new HashMap<String, TestTypes.Sub>();
@@ -433,4 +449,8 @@ public class MapTest extends TestCase {
       subs.put(name, value);
     }
   }
+
+  static final class MapWithGeneralMapParameters {
+    final Map<String, Object> map = new LinkedHashMap();
+  }
 }

gson/src/test/java/com/google/gson/functional/MoreSpecificTypeSerializationTest.java

@@ -48,14 +48,14 @@ public class MoreSpecificTypeSerializationTest extends TestCase {
     assertTrue(json.contains("\"s\":2"));
   }
 
-  public void disabled_testListOfSubclassFields() {
+  public void testListOfSubclassFields() {
     Collection<Base> list = new ArrayList<Base>();
     list.add(new Base(1));
     list.add(new Sub(2, 3));
     ClassWithContainersOfBaseFields target = new ClassWithContainersOfBaseFields(list, null);
     String json = gson.toJson(target);
     assertTrue(json, json.contains("{\"b\":1}"));
-    assertTrue(json, json.contains("{\"b\":2,\"s\":3}"));
+    assertTrue(json, json.contains("{\"s\":3,\"b\":2}"));
   }
 
   public void testMapOfSubclassFields() {