Fixed resolving generic types for Vavr maps.

Issue #2517.

Author: nexx512

src/main/java/org/springframework/data/util/ParameterizedTypeInformation.java

@@ -39,6 +39,7 @@
  * @author Oliver Gierke
  * @author Mark Paluch
  * @author Christoph Strobl
+ * @author Jürgen Diez
  */
 class ParameterizedTypeInformation<T> extends ParentTypeAwareTypeInformation<T> {
 
@@ -67,7 +68,7 @@ public ParameterizedTypeInformation(ParameterizedType type, TypeDiscoverer<?> pa
 	@Nullable
 	protected TypeInformation<?> doGetMapValueType() {
 
-		if (Map.class.isAssignableFrom(getType())) {
+		if (isMap()) {
 
 			Type[] arguments = type.getActualTypeArguments();
 
@@ -157,13 +158,13 @@ public boolean isAssignableFrom(TypeInformation<?> target) {
 	@Nullable
 	protected TypeInformation<?> doGetComponentType() {
 
-		boolean isCustomMapImplementation = isMap() && !getType().equals(Map.class);
+		boolean isCustomMapImplementation = isMap() && !isMapBaseType();
 
 		if (isCustomMapImplementation) {
-			return getRequiredSuperTypeInformation(Map.class).getComponentType();
+			return getRequiredSuperTypeInformation(getMapBaseType()).getComponentType();
 		}
 
-		return createInfo(type.getActualTypeArguments()[0]);
+		return createInfo(this.type.getActualTypeArguments()[0]);
 	}
 
 	/*

src/main/java/org/springframework/data/util/TypeDiscoverer.java

@@ -47,7 +47,7 @@
  */
 class TypeDiscoverer<S> implements TypeInformation<S> {
 
-	private static final Class<?>[] MAP_TYPES;
+	protected static final Class<?>[] MAP_TYPES;
 	private static final Class<?>[] COLLECTION_TYPES;
 
 	static {
@@ -361,7 +361,7 @@ public TypeInformation<?> getMapValueType() {
 
 	@Nullable
 	protected TypeInformation<?> doGetMapValueType() {
-		return isMap() ? getTypeArgument(getBaseType(MAP_TYPES), 1)
+		return isMap() ? getTypeArgument(getMapBaseType(), 1)
 				: getTypeArguments().stream().skip(1).findFirst().orElse(null);
 	}
 
@@ -398,7 +398,7 @@ protected TypeInformation<?> doGetComponentType() {
 		}
 
 		if (isMap()) {
-			return getTypeArgument(getBaseType(MAP_TYPES), 0);
+			return getTypeArgument(getMapBaseType(), 0);
 		}
 
 		if (Iterable.class.isAssignableFrom(rawType)) {
@@ -533,6 +533,27 @@ private TypeInformation<?> getTypeArgument(Class<?> bound, int index) {
 				: null;
 	}
 
+	protected boolean isMapBaseType() {
+		return isBaseType(MAP_TYPES);
+	}
+
+	private boolean isBaseType(Class<?>[] candidates) {
+
+		Class<S> type = getType();
+
+		for (Class<?> candidate: candidates) {
+			if (candidate.equals(type)) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	protected Class<?> getMapBaseType() {
+		return getBaseType(MAP_TYPES);
+	}
+
 	private Class<?> getBaseType(Class<?>[] candidates) {
 
 		Class<S> type = getType();

src/test/java/org/springframework/data/util/ParameterizedTypeInformationUnitTests.java

@@ -40,6 +40,7 @@
  *
  * @author Oliver Gierke
  * @author Mark Paluch
+ * @author Jürgen Diez
  */
 @ExtendWith(MockitoExtension.class)
 @MockitoSettings(strictness = Strictness.LENIENT)
@@ -76,22 +77,39 @@ void considersTypeInformationsWithSameParentsNotEqual() {
 	}
 
 	@Test // DATACMNS-88
-	void resolvesMapValueTypeCorrectly() {
+	void resolvesMapTypesCorrectly() {
 
 		TypeInformation<Foo> type = ClassTypeInformation.from(Foo.class);
 		TypeInformation<?> propertyType = type.getProperty("param");
 		TypeInformation<?> value = propertyType.getProperty("value");
 
+		assertThat(propertyType.getComponentType().getType()).isEqualTo(Locale.class);
 		assertThat(value.getType()).isEqualTo(String.class);
 		assertThat(propertyType.getMapValueType().getType()).isEqualTo(String.class);
 
 		propertyType = type.getProperty("param2");
 		value = propertyType.getProperty("value");
 
+		assertThat(propertyType.getComponentType().getType()).isEqualTo(String.class);
 		assertThat(value.getType()).isEqualTo(String.class);
 		assertThat(propertyType.getMapValueType().getType()).isEqualTo(Locale.class);
 	}
 
+	@Test
+	void resolvesVavrMapTypesCorrectly() {
+
+		TypeInformation<VavrFoo> type = ClassTypeInformation.from(VavrFoo.class);
+		TypeInformation<?> propertyType = type.getProperty("param");
+
+		assertThat(propertyType.getComponentType().getType()).isEqualTo(Locale.class);
+		assertThat(propertyType.getMapValueType().getType()).isEqualTo(String.class);
+
+		propertyType = type.getProperty("param2");
+
+		assertThat(propertyType.getComponentType().getType()).isEqualTo(String.class);
+		assertThat(propertyType.getMapValueType().getType()).isEqualTo(Locale.class);
+	}
+
 	@Test // DATACMNS-446
 	void createsToStringRepresentation() {
 
@@ -170,6 +188,11 @@ class Foo {
 		Localized2<String> param2;
 	}
 
+	class VavrFoo {
+		io.vavr.collection.HashMap<Locale, String> param;
+		io.vavr.collection.HashMap<String, Locale> param2;
+	}
+
 	class Bar {
 		List<String> param;
 	}

src/test/java/org/springframework/data/util/TypeDiscovererUnitTests.java

@@ -188,6 +188,15 @@ void considerVavrMapToBeAMap() {
 		assertThat(type.isMap()).isTrue();
 	}
 
+	@Test // #2517
+	void returnsComponentAndValueTypesForVavrMapExtensions() {
+
+		TypeInformation<?> discoverer = new TypeDiscoverer<>(CustomVavrMap.class, EMPTY_MAP);
+
+		assertThat(discoverer.getMapValueType().getType()).isEqualTo(Locale.class);
+		assertThat(discoverer.getComponentType().getType()).isEqualTo(String.class);
+	}
+
 	@Test
 	void considerVavrSetToBeCollectionLike() {
 
@@ -261,4 +270,6 @@ public Iterator<String> iterator() {
 			return Collections.emptyIterator();
 		}
 	}
+
+	interface CustomVavrMap extends io.vavr.collection.Map<String, Locale> {}
 }