Remove Copyable, add tests

sdk/java/pulumi/src/main/java/com/pulumi/resources/StackOptions.java

@@ -1,7 +1,5 @@
 package com.pulumi.resources;
 
-import com.pulumi.core.internal.Copyable;
-
 import javax.annotation.Nullable;
 import javax.annotation.ParametersAreNonnullByDefault;
 import java.util.List;
@@ -13,7 +11,7 @@
  * @see StackOptions is a bag of optional settings that control a stack's behavior.
  */
 @ParametersAreNonnullByDefault
-public class StackOptions implements Copyable<StackOptions> {
+public class StackOptions {
 
     public static final StackOptions Empty = new Builder().build();
 
@@ -40,12 +38,6 @@ public List<ResourceTransformation> resourceTransformations() {
         return this.resourceTransformations;
     }
 
-    public StackOptions copy() {
-        return new StackOptions(
-                this.resourceTransformations
-        );
-    }
-
     /**
      * @return a {@link StackOptions} builder instance
      */
@@ -100,11 +92,11 @@ public StackOptions build() {
      * @return a new {@link StackOptions} with merged values
      */
     public static StackOptions merge(@Nullable StackOptions options1, @Nullable StackOptions options2) {
-        options1 = options1 != null ? options1.copy() : Empty;
-        options2 = options2 != null ? options2.copy() : Empty;
+        var opt1 = options1 != null ? options1 : Empty;
+        var opt2 = options2 != null ? options2 : Empty;
 
         var resourceTransformations = requireNonNull(mergeNullableList(
-                options1.resourceTransformations, options2.resourceTransformations
+                opt1.resourceTransformations, opt2.resourceTransformations
         ));
         return new StackOptions(resourceTransformations);
     }

sdk/java/pulumi/src/test/java/com/pulumi/resources/StackOptionsTest.java

@@ -0,0 +1,66 @@
+package com.pulumi.resources;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+import javax.annotation.Nullable;
+import java.util.List;
+import java.util.Optional;
+import java.util.stream.Stream;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.params.provider.Arguments.arguments;
+
+class StackOptionsTest {
+
+    public static Stream<Arguments> testMerge() {
+        final ResourceTransformation transformation1 = args -> Optional.empty();
+        final ResourceTransformation transformation2 = args -> Optional.empty();
+        return Stream.of(
+                arguments(
+                        null,
+                        null,
+                        new StackOptions(List.of())
+                ),
+                arguments(
+                        null,
+                        new StackOptions(List.of()),
+                        new StackOptions(List.of())
+                ),
+                arguments(
+                        new StackOptions(List.of()),
+                        null,
+                        new StackOptions(List.of())
+                ),
+                arguments(
+                        new StackOptions(List.of()),
+                        new StackOptions(List.of()),
+                        new StackOptions(List.of())
+                ),
+                arguments(
+                        new StackOptions(List.of(transformation1)),
+                        new StackOptions(List.of()),
+                        new StackOptions(List.of(transformation1))
+                ),
+                arguments(
+                        new StackOptions(List.of()),
+                        new StackOptions(List.of(transformation1)),
+                        new StackOptions(List.of(transformation1))
+                ),
+                arguments(
+                        new StackOptions(List.of(transformation1)),
+                        new StackOptions(List.of(transformation2)),
+                        new StackOptions(List.of(transformation1, transformation2))
+                )
+        );
+    }
+
+    @ParameterizedTest
+    @MethodSource
+    void testMerge(@Nullable StackOptions first, @Nullable StackOptions second, StackOptions expected) {
+        var result = StackOptions.merge(first, second);
+
+        assertThat(result.resourceTransformations()).containsExactlyElementsOf(expected.resourceTransformations());
+    }
+}