bug(*): fix method resolution for inner interfaces

This fixes the method CtType#getAllExecutables and handles inner now
interfaces correctly as implicitly static.

src/main/java/spoon/support/visitor/ClassTypingContext.java

@@ -364,6 +364,10 @@ private CtTypeReference<?> getEnclosingType(CtTypeReference<?> typeRef) {
 			if (declType == null) {
 				return null;
 			}
+			if (type.isInterface()) {
+				// Case: we have a declaring type and the inner type is an interface. So the nested interface is implicitly static.
+				return null;
+			}
 			if (declType.isInterface()) {
 				//nested types of interfaces are static
 				return null;

src/test/java/spoon/test/method/MethodTest.java

@@ -18,6 +18,7 @@
 
 import org.junit.Test;
 import spoon.Launcher;
+import spoon.reflect.CtModel;
 import spoon.reflect.declaration.CtClass;
 import spoon.reflect.declaration.CtMethod;
 import spoon.reflect.declaration.CtParameter;
@@ -33,6 +34,7 @@
 
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.ConcurrentModificationException;
 import java.util.HashSet;
 import java.util.Set;
@@ -43,6 +45,7 @@
 import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 import static spoon.testing.utils.ModelUtils.build;
 import static spoon.testing.utils.ModelUtils.buildClass;
 import static spoon.testing.utils.ModelUtils.createFactory;
@@ -218,4 +221,15 @@ public void test_addFormalCtTypeParameterAt_throwsOutOfBoundsException_whenPosit
 		assertThrows(IndexOutOfBoundsException.class,
 				() -> method.addFormalCtTypeParameterAt(1, typeParam));
 	}
+
+	@Test
+	public void testGetAllMethodsInnerClassExtended() {
+		// contract: implicit static nested interfaces are correct handled in getAllExecutables and dont throw an error.
+		Launcher launcher = new Launcher();
+		launcher.addInputResource("src/test/resources/extendsStaticInnerType");
+		CtModel model = launcher.buildModel();
+		CtType<?> type = model.getAllTypes().stream().filter(v -> v.getSimpleName().contains("BarBaz")).findAny().get();
+		assertDoesNotThrow(() -> type.getAllExecutables());
+		assertEquals(13, type.getAllExecutables().size());
+	}
 }

src/test/resources/extendsStaticInnerType/BarBaz.java

@@ -0,0 +1,10 @@
+package extendsStaticInnerType;
+
+public class BarBaz implements FooBar.Crashy {
+
+  @Override
+  public String foo() {
+    return "bar!";
+  }
+
+}

src/test/resources/extendsStaticInnerType/FooBar.java

@@ -0,0 +1,9 @@
+package extendsStaticInnerType;
+
+public class FooBar {
+
+  public interface Crashy {
+
+    String foo();
+  }
+}