Fix union serialization

Author: marcospassos

avro/src/main/java/com/fasterxml/jackson/dataformat/avro/ser/AvroWriteContext.java

@@ -276,8 +276,7 @@ public static int resolveUnionIndex(Schema unionSchema, Object datum) {
             // !!! TODO:
             //  - ByteBuffer
             //  - Number wrappers (Integer, ...)
-            
-            /*
+
             String typeId = AvroSchemaHelper.getTypeId(datum.getClass());
             for (int i = 0, size = types.size(); i < size; ++i) {
                 Schema schema = types.get(i);
@@ -286,7 +285,6 @@ public static int resolveUnionIndex(Schema unionSchema, Object datum) {
                     return i;
                 }
             }
-            */
         }
 //System.err.println("Missing index for: "+datum.getClass().getName()+" ("+types.size()+") ->\n"+types);  
         return ReflectData.get().resolveUnion(unionSchema, datum);
@@ -328,7 +326,6 @@ public static Schema resolveUnionType(Schema unionSchema, Object datum) {
                 return types.get(_resolveMapIndex(unionSchema, types, datum));
             }
 
-            /*
             String typeId = AvroSchemaHelper.getTypeId(datum.getClass());
             for (int i = 0, size = types.size(); i < size; ++i) {
                 Schema schema = types.get(i);
@@ -337,7 +334,6 @@ public static Schema resolveUnionType(Schema unionSchema, Object datum) {
                     return schema;
                 }
             }
-            */
         }
 //System.err.println("Missing schema for: "+datum.getClass().getName()+" ("+types.size()+") ->\n"+types);  
         int ix = ReflectData.get().resolveUnion(unionSchema, datum);

avro/src/test/java/com/fasterxml/jackson/dataformat/avro/interop/annotations/UnionResolvingTest.java

@@ -0,0 +1,90 @@
+package com.fasterxml.jackson.dataformat.avro.interop.annotations;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Objects;
+import java.util.Set;
+import org.apache.avro.Schema;
+import org.apache.avro.SchemaBuilder;
+import org.apache.avro.reflect.Union;
+import org.junit.Test;
+
+import static com.fasterxml.jackson.dataformat.avro.interop.ApacheAvroInteropUtil.jacksonDeserialize;
+import static com.fasterxml.jackson.dataformat.avro.interop.ApacheAvroInteropUtil.jacksonSerialize;
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class UnionResolvingTest {
+    private Schema SCHEMA = SchemaBuilder
+        .builder(UnionResolvingTest.class.getName() + "$")
+        .record(Box.class.getSimpleName())
+            .fields()
+            .name("animal")
+            .type()
+            .unionOf()
+                .record(Cat.class.getSimpleName())
+                    .fields()
+                    .name("name").type().stringType().noDefault()
+                .endRecord()
+            .and()
+                .record(Dog.class.getSimpleName())
+                .fields()
+                    .name("tricks").type().array().items().stringType().noDefault()
+                .endRecord()
+            .endUnion()
+            .noDefault()
+        .endRecord();
+
+
+    @Union({ Cat.class, Dog.class })
+    public interface Animal { }
+
+    static final class Cat implements Animal {
+        public Cat() {}
+
+        @Override
+        public boolean equals(Object o) {
+            return o instanceof Cat;
+        }
+    }
+
+    static final class Dog implements Animal {
+        // Unsupported schema generation
+        public Set<?> tricks = new HashSet<>();
+
+        public Dog() {
+        }
+
+        public Dog(final Set<?> tricks) {
+            this.tricks = tricks;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            return o instanceof Dog && tricks.equals(((Dog) o).tricks);
+        }
+    }
+
+    public static class Box {
+        public Animal animal;
+
+        public Box() {
+        }
+
+        public Box(Animal a) { animal = a; }
+
+        @Override
+        public boolean equals(Object o) {
+            return o instanceof Box && Objects.equals(animal, ((Box) o).animal);
+        }
+    }
+
+    @Test
+    public void testResolveUnionUsingSchemaName() throws IOException {
+        final Box box = new Box(new Dog(Collections.singleton("catch stick")));
+
+        final Box result = jacksonDeserialize(SCHEMA, Box.class, jacksonSerialize(SCHEMA, box));
+
+        assertThat(result).isEqualTo(box);
+    }
+}