fix: bug regression with lambda expression when extending Function

src/main/java/spoon/support/reflect/code/CtLambdaImpl.java

@@ -109,7 +109,7 @@ public <R> CtMethod<R> getOverriddenMethod() {
 			lambdaExecutableMethod = lambdaTypeMethods.iterator().next();
 		} else {
 			for (CtMethod<?> method : lambdaTypeMethods) {
-				if (method.isDefaultMethod() || method.hasModifier(ModifierKind.PRIVATE)) {
+				if (method.isDefaultMethod() || method.hasModifier(ModifierKind.PRIVATE) || method.hasModifier(ModifierKind.STATIC)) {
 					continue;
 				}
 				if (lambdaExecutableMethod != null) {

src/test/java/spoon/test/lambda/LambdaTest.java

@@ -23,13 +23,16 @@
 import spoon.test.lambda.testclasses.Bar;
 import spoon.test.lambda.testclasses.Foo;
 import spoon.test.lambda.testclasses.Kuu;
+import spoon.test.lambda.testclasses.LambdaRxJava;
 import spoon.test.lambda.testclasses.Panini;
 import spoon.test.lambda.testclasses.Tacos;
 import spoon.testing.utils.ModelUtils;
 
 import java.io.File;
 import java.util.List;
+import java.util.Set;
 import java.util.function.Consumer;
+import java.util.function.Function;
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
@@ -47,6 +50,7 @@ public class LambdaTest {
 	private CtType<Bar> bar;
 	private CtType<Object> panini;
 	private CtType<Object> tacos;
+	private CtType<LambdaRxJava> lambdaRxJava;
 	private SpoonModelBuilder compiler;
 
 	@Before
@@ -64,6 +68,7 @@ public void setUp() throws Exception {
 		bar = factory.Type().get(Bar.class);
 		panini = factory.Type().get(Panini.class);
 		tacos = factory.Type().get(Tacos.class);
+		lambdaRxJava = factory.Type().get(LambdaRxJava.class);
 	}
 
 	@Test
@@ -369,6 +374,16 @@ public void testLambdaMethod() throws Exception {
 */
 	}
 
+	@Test
+	public void testGetOverriddenMethodWithFunction() throws Exception {
+		List<CtLambda<?>> allLambdas = lambdaRxJava.getElements(new TypeFilter<CtLambda<?>>(CtLambda.class));
+		assertEquals(1, allLambdas.size());
+		CtLambda<?> lambda = allLambdas.get(0);
+		CtMethod<?> method = lambda.getOverriddenMethod();
+		CtTypeReference<?> iface = lambda.getType();
+		assertEquals(LambdaRxJava.NbpOperator.class.getName(), iface.getQualifiedName());
+	}
+
 	private void assertTypedBy(Class<?> expectedType, CtTypeReference<?> type) {
 		assertEquals("Lambda must be typed", expectedType, type.getActualClass());
 	}

src/test/java/spoon/test/lambda/testclasses/LambdaRxJava.java

@@ -0,0 +1,18 @@
+package spoon.test.lambda.testclasses;
+
+import java.util.function.Function;
+
+/**
+ * Created by urli on 09/02/2017.
+ */
+public class LambdaRxJava {
+    public interface NbpOperator extends Function<String, Integer> {}
+
+    public Integer bla(NbpOperator toto) {
+        return toto.apply("truc");
+    }
+
+    public void toto() {
+        bla((NbpOperator) t -> { return t.length(); });
+    }
+}