New (failing) test to demonstrate that we're broken with precedence of streaming vs. nonstreaming type adapters.

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

@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2011 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.gson.functional;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import com.google.gson.JsonDeserializationContext;
+import com.google.gson.JsonDeserializer;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonParseException;
+import com.google.gson.JsonPrimitive;
+import com.google.gson.JsonSerializationContext;
+import com.google.gson.JsonSerializer;
+import com.google.gson.TypeAdapter;
+import com.google.gson.stream.JsonReader;
+import com.google.gson.stream.JsonWriter;
+import java.io.IOException;
+import java.lang.reflect.Type;
+import junit.framework.TestCase;
+
+public final class TypeAdapterPrecedenceTest extends TestCase {
+  private static final JsonSerializer<Foo> FOO_SERIALIZER = new JsonSerializer<Foo>() {
+    public JsonElement serialize(Foo src, Type typeOfSrc, JsonSerializationContext context) {
+      return new JsonPrimitive(src.name + " (via FOO_SERIALIZER)");
+    }
+  };
+
+  private static final JsonDeserializer<Foo> FOO_DESERIALIZER = new JsonDeserializer<Foo>() {
+    public Foo deserialize(JsonElement json, Type typeOfT,
+        JsonDeserializationContext context) throws JsonParseException {
+      return new Foo(json.getAsString() + " (via FOO_DESERIALIZER)");
+    }
+  };
+
+  private static final TypeAdapter<Foo> FOO_TYPE_ADAPTER = new TypeAdapter<Foo>() {
+    @Override public Foo read(JsonReader reader) throws IOException {
+      return new Foo(reader.nextString() + " (via FOO_TYPE_ADAPTER)");
+    }
+    @Override public void write(JsonWriter writer, Foo value) throws IOException {
+      writer.value(value.name + " (via FOO_TYPE_ADAPTER)");
+    }
+  };
+
+  public void testSerializeNonstreamingTypeAdapterFollowedByStreamingTypeAdapter() {
+    Gson gson = new GsonBuilder()
+        .registerTypeAdapter(Foo.class, FOO_SERIALIZER)
+        .typeAdapter(Foo.class, FOO_TYPE_ADAPTER)
+        .create();
+    assertEquals("\"foo (via FOO_SERIALIZER)\"", gson.toJson(new Foo("foo")));
+  }
+
+  public void testSerializeStreamingTypeAdapterFollowedByNonstreamingTypeAdapter() {
+    Gson gson = new GsonBuilder()
+        .typeAdapter(Foo.class, FOO_TYPE_ADAPTER)
+        .registerTypeAdapter(Foo.class, FOO_SERIALIZER)
+        .create();
+    assertEquals("\"foo (via FOO_TYPE_ADAPTER)\"", gson.toJson(new Foo("foo")));
+  }
+
+  public void testDeserializeNonstreamingTypeAdapterFollowedByStreamingTypeAdapter() {
+    Gson gson = new GsonBuilder()
+        .registerTypeAdapter(Foo.class, FOO_DESERIALIZER)
+        .typeAdapter(Foo.class, FOO_TYPE_ADAPTER)
+        .create();
+    assertEquals("foo (via FOO_DESERIALIZER)", gson.fromJson("foo", Foo.class).name);
+  }
+
+  public void testDeserializeStreamingTypeAdapterFollowedByNonstreamingTypeAdapter() {
+    Gson gson = new GsonBuilder()
+        .typeAdapter(Foo.class, FOO_TYPE_ADAPTER)
+        .registerTypeAdapter(Foo.class, FOO_DESERIALIZER)
+        .create();
+    assertEquals("foo (via FOO_TYPE_ADAPTER)", gson.fromJson("foo", Foo.class).name);
+  }
+
+  private static class Foo {
+    private final String name;
+    private Foo(String name) {
+      this.name = name;
+    }
+  }
+}