Fix FunctionalInterface supports equals, hashCode, toString

naver · Feb 8, 2025 · 68fc772 · 68fc772
1 parent fdbecc3
commit 68fc772
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Showing 4 changed files with 63 additions and 19 deletions.
diff --git a/...om/navercorp/fixturemonkey/api/introspector/FunctionalInterfaceArbitraryIntrospector.java b/...om/navercorp/fixturemonkey/api/introspector/FunctionalInterfaceArbitraryIntrospector.java
@@ -19,8 +19,12 @@
 package com.navercorp.fixturemonkey.api.introspector;
 
 import java.lang.reflect.Proxy;
+import java.util.HashMap;
 import java.util.List;
-import java.util.Objects;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.function.Function;
+import java.util.function.Supplier;
 
 import org.apiguardian.api.API;
 
@@ -31,6 +35,14 @@
 
 @API(since = "1.0.21", status = API.Status.EXPERIMENTAL)
 public final class FunctionalInterfaceArbitraryIntrospector implements ArbitraryIntrospector {
+	private static final Map<Class<?>, String> FUNCTIONAL_INVOKE_METHOD_NAMES_BY_ASSIGNABLE_TYPE = new HashMap<>();
+	private static final String INVOKE_METHOD_NAME = "invoke";
+
+	static {
+		FUNCTIONAL_INVOKE_METHOD_NAMES_BY_ASSIGNABLE_TYPE.put(Function.class, "apply");
+		FUNCTIONAL_INVOKE_METHOD_NAMES_BY_ASSIGNABLE_TYPE.put(Supplier.class, "get");
+	}
+
 	@Override
 	public ArbitraryIntrospectorResult introspect(ArbitraryGeneratorContext context) {
 		ArbitraryProperty property = context.getArbitraryProperty();
@@ -47,18 +59,26 @@ public ArbitraryIntrospectorResult introspect(ArbitraryGeneratorContext context)
 		return new ArbitraryIntrospectorResult(result);
 	}
 
-	@SuppressWarnings("SuspiciousInvocationHandlerImplementation")
 	private <T> Object toFunctionalInterface(Class<?> type, T value) {
+		InvocationHandlerBuilder invocationHandlerBuilder = new InvocationHandlerBuilder(
+			type,
+			new HashMap<>()
+		);
+
+		for (Entry<Class<?>, String> entry : FUNCTIONAL_INVOKE_METHOD_NAMES_BY_ASSIGNABLE_TYPE.entrySet()) {
+			if (entry.getKey().isAssignableFrom(type)) {
+				invocationHandlerBuilder.put(entry.getValue(), value);
+			}
+		}
+
+		if (invocationHandlerBuilder.isEmpty()) {
+			invocationHandlerBuilder.put(INVOKE_METHOD_NAME, value);
+		}
+
 		return Proxy.newProxyInstance(
 			type.getClassLoader(),
 			new Class[] {type},
-			(proxy, method, args) -> {
-				if (method != null && "equals".equals(method.getName())) {
-					return Objects.equals(args[0], value);
-				}
-
-				return value;
-			}
+			invocationHandlerBuilder.build()
 		);
 	}
 }
diff --git a/.../src/main/java/com/navercorp/fixturemonkey/api/introspector/InvocationHandlerBuilder.java b/.../src/main/java/com/navercorp/fixturemonkey/api/introspector/InvocationHandlerBuilder.java
@@ -34,6 +34,7 @@ final class InvocationHandlerBuilder {
 	private static final String HASH_CODE_METHOD = "hashCode";
 	private static final String EQUALS_METHOD = "equals";
 	private static final String TO_STRING_METHOD = "toString";
+	private static final String INVOKE_METHOD = "invoke";
 
 	private final Class<?> type;
 	private final Map<String, Object> generatedValuesByMethodName;
@@ -52,6 +53,11 @@ void put(String methodName, Object value) {
 
 	InvocationHandler build() {
 		return (proxy, method, args) -> {
+			if (method == null) {
+				// invoked by DecomposedContainerValueFactory to decompose the functional interface
+				return generatedValuesByMethodName.get(INVOKE_METHOD);
+			}
+
 			if (HASH_CODE_METHOD.equals(method.getName()) && args == null) {
 				return generatedValuesByMethodName.values().hashCode();
 			}
@@ -65,11 +71,6 @@ InvocationHandler build() {
 				return toString(proxy);
 			}
 
-			// check no-args
-			if (args != null) {
-				return null;
-			}
-
 			return generatedValuesByMethodName.get(method.getName());
 		};
 	}

diff --git a/...rc/main/java17/com/navercorp/fixturemonkey/api/introspector/InvocationHandlerBuilder.java b/...rc/main/java17/com/navercorp/fixturemonkey/api/introspector/InvocationHandlerBuilder.java
@@ -35,6 +35,7 @@ final class InvocationHandlerBuilder {
 	private static final String HASH_CODE_METHOD = "hashCode";
 	private static final String EQUALS_METHOD = "equals";
 	private static final String TO_STRING_METHOD = "toString";
+	private static final String INVOKE_METHOD = "invoke";
 
 	private final Class<?> type;
 	private final Map<String, Object> generatedValuesByMethodName;
@@ -53,6 +54,11 @@ void put(String methodName, Object value) {
 
 	InvocationHandler build() {
 		return (proxy, method, args) -> {
+			if (method == null) {
+				// invoked by DecomposedContainerValueFactory to decompose the functional interface
+				return generatedValuesByMethodName.get(INVOKE_METHOD);
+			}
+
 			if (method.isDefault()) {
 				return InvocationHandler.invokeDefault(proxy, method, args);
 			}
@@ -70,11 +76,6 @@ InvocationHandler build() {
 				return toString(proxy);
 			}
 
-			// check no-args
-			if (args != null) {
-				return null;
-			}
-
 			return generatedValuesByMethodName.get(method.getName());
 		};
 	}

diff --git a/...tests/kotlin-tests/src/test/kotlin/com/navercorp/fixturemonkey/tests/kotlin/KotlinTest.kt b/...tests/kotlin-tests/src/test/kotlin/com/navercorp/fixturemonkey/tests/kotlin/KotlinTest.kt
@@ -73,6 +73,7 @@ import com.navercorp.fixturemonkey.tests.kotlin.ImmutableJavaTestSpecs.ArrayObje
 import com.navercorp.fixturemonkey.tests.kotlin.ImmutableJavaTestSpecs.NestedArrayObject
 import com.navercorp.fixturemonkey.tests.kotlin.JavaConstructorTestSpecs.JavaTypeObject
 import org.assertj.core.api.BDDAssertions.then
+import org.assertj.core.api.BDDAssertions.thenNoException
 import org.assertj.core.api.BDDAssertions.thenThrownBy
 import org.junit.jupiter.api.RepeatedTest
 import org.junit.jupiter.api.Test
@@ -1352,6 +1353,27 @@ class KotlinTest {
         then(actual).allMatch { it.value == "1" }
     }
 
+    @Test
+    fun sampleFunctionalObject() {
+        data class FunctionObject(
+            val value: () -> Int
+        )
+
+        val actual = SUT.giveMeOne<FunctionObject>().value()
+
+        then(actual).isNotNull()
+    }
+
+    @Test
+    fun toStringFunctionalObjectNotThrows() {
+        data class FunctionObject(
+            val value: () -> Int
+        )
+
+        thenNoException()
+            .isThrownBy { SUT.giveMeOne<FunctionObject>().toString() }
+    }
+
     companion object {
         private val SUT: FixtureMonkey = FixtureMonkey.builder()
             .plugin(KotlinPlugin())