Fixed bug #519

engine/src/main/java/net/jqwik/engine/support/GenericsClassContext.java

@@ -120,17 +120,28 @@ private TypeResolution resolveVariableLocally(TypeResolution typeResolution) {
 	}
 
 	private TypeResolution resolveVariableInSupertypes(TypeResolution typeResolution) {
-		return supertypeContexts()
-				   .map(context -> context.resolveVariableLocally(typeResolution))
-				   .filter(TypeResolution::typeHasChanged)
+		// TODO: Optimize so that only get supertypes of supertypes if necessary
+		//       i.e. it cannot be resolved in direct supertypes
+		Set<TypeUsage> superTypes = getAllSupertypes(contextType);
+		List<TypeResolution> typeResolutionList =
+			superTypes.stream()
+					  .map(GenericsSupport::contextFor)
+					  .map(context -> context.resolveVariableLocally(typeResolution))
+					  .filter(TypeResolution::typeHasChanged)
+					  .collect(Collectors.toList());
+
+		return typeResolutionList.stream()
 				   .findFirst()
 				   .orElse(typeResolution.unchanged());
 	}
 
-	private Stream<GenericsClassContext> supertypeContexts() {
-		Stream<TypeUsage> superclassStream = contextType.getSuperclass().map(Stream::of).orElseGet(Stream::empty);
-		Stream<TypeUsage> interfacesStream = contextType.getInterfaces().stream();
-		return Stream.concat(superclassStream, interfacesStream).map(GenericsSupport::contextFor);
+	private Set<TypeUsage> getAllSupertypes(TypeUsage contextType) {
+        List<TypeUsage> directSupertypes = contextType.getSuperTypes();
+        Set<TypeUsage> allSupertypes = new LinkedHashSet<>(directSupertypes);
+		for (TypeUsage directSupertype : directSupertypes) {
+			allSupertypes.addAll(getAllSupertypes(directSupertype));
+		}
+		return allSupertypes;
 	}
 
 	private static class LookupTypeVariable {

engine/src/test/java/examples/bugs/Issue519Bug.java

@@ -0,0 +1,45 @@
+package examples.bugs;
+
+import net.jqwik.api.*;
+
+// See https://github.com/jqwik-team/jqwik/issues/519
+class Issue519Bug implements C<MyRecord> {
+	@Provide("anyT")
+	@Override
+	public Arbitrary<MyRecord> anyT() {
+		return Arbitraries.of(new MyRecord());
+	}
+}
+
+interface A<T> {
+	@Property
+	default boolean test1(@ForAll("anyT") T t) {
+		return true;
+	}
+
+	Arbitrary<T> anyT();
+}
+
+interface B<T extends Comparable<? super T>> extends A<T> {
+	@Property
+	default boolean test2(@ForAll("anyT") T t) {
+		return true;
+	}
+}
+
+interface MyType extends Comparable<MyType> { }
+
+interface C<T extends MyType> extends B<T> {
+	@Property
+	default boolean test3(@ForAll("anyT") T t) {
+		return true;
+	}
+}
+
+class MyRecord implements MyType {
+	@Override
+	public int compareTo(MyType o) {
+		return 0;
+	}
+}
+

engine/src/test/java/net/jqwik/engine/support/GenericsSupportTests.java

@@ -273,9 +273,43 @@ class Inner3 extends Inner2<String> {}
 			assertThat(typeUsage.isOfType(GenericType.class)).isTrue();
 			assertThat(typeUsage.getTypeArguments()).hasSize(1);
 			assertThat(typeUsage.getTypeArgument(0).isOfType(String.class)).isTrue();
+		}
+	}
+
+	@Example
+	@Label("Bug from issue#519")
+	void bug519() throws NoSuchMethodException {
+		abstract class A<T> {
+			public boolean myMethod(T t) {
+				return true;
+			}
+		}
+
+		abstract class B<T extends Comparable<? super T>> extends A<T> {
+		}
+
+		abstract class MyType implements Comparable<MyType> { }
 
+		abstract class C<T extends MyType> extends B<T> {
 		}
 
+		class MyRecord extends MyType {
+			@Override
+			public int compareTo(MyType o) {
+				return 0;
+			}
+		}
+
+		class ConcreteC extends C<MyRecord> {
+		}
+
+		GenericsClassContext context = GenericsSupport.contextFor(ConcreteC.class);
+		Method method = A.class.getMethod("myMethod", Object.class);
+
+		TypeResolution resolution = context.resolveParameter(method.getParameters()[0]);
+		TypeUsage typeUsage = TypeUsageImpl.forResolution(resolution);
+
+		assertThat(typeUsage.isOfType(MyRecord.class)).isTrue();
 	}
 
 	@Group