Update SuperficialValidation to validate supertypes and superinterfaces recursively.

Author: Leland Takamine

common/src/main/java/com/google/auto/common/SuperficialValidation.java

@@ -17,6 +17,7 @@
 
 import java.util.List;
 import java.util.Map;
+import java.util.stream.Collectors;
 import javax.lang.model.element.AnnotationMirror;
 import javax.lang.model.element.AnnotationValue;
 import javax.lang.model.element.AnnotationValueVisitor;
@@ -63,10 +64,13 @@ public static boolean validateElements(Iterable<? extends Element> elements) {
         }
 
         @Override public Boolean visitType(TypeElement e, Void p) {
+          TypeMirror superclass = e.getSuperclass();
           return isValidBaseElement(e)
               && validateElements(e.getTypeParameters())
               && validateTypes(e.getInterfaces())
-              && validateType(e.getSuperclass());
+              && validateType(superclass)
+              && validateElements(e.getInterfaces().stream().map(MoreTypes::asElement).collect(Collectors.toList()))
+              && (superclass.getKind() == TypeKind.NONE || validateElement(MoreTypes.asElement(superclass)));
         }
 
         @Override public Boolean visitVariable(VariableElement e, Void p) {

common/src/test/java/com/google/auto/common/SuperficialValidationTest.java

@@ -276,6 +276,90 @@ void runAssertions() {
         .failsToCompile();
   }
 
+  @Test
+  public void missingSuperclass() {
+    JavaFileObject javaFileObject = JavaFileObjects.forSourceLines(
+        "test.TestClass",
+        "package test;",
+        "",
+        "class TestClass extends Missing {}");
+    assertAbout(javaSource())
+        .that(javaFileObject)
+        .processedWith(new AssertingProcessor() {
+          @Override
+          void runAssertions() {
+            TypeElement testClassElement =
+                processingEnv.getElementUtils().getTypeElement("test.TestClass");
+            assertThat(SuperficialValidation.validateElement(testClassElement)).isFalse();
+          }
+        })
+        .failsToCompile();
+  }
+
+  @Test
+  public void missingSuperinterface() {
+    JavaFileObject javaFileObject = JavaFileObjects.forSourceLines(
+        "test.TestClass",
+        "package test;",
+        "",
+        "class TestClass implements Missing {}");
+    assertAbout(javaSource())
+        .that(javaFileObject)
+        .processedWith(new AssertingProcessor() {
+          @Override
+          void runAssertions() {
+            TypeElement testClassElement =
+                processingEnv.getElementUtils().getTypeElement("test.TestClass");
+            assertThat(SuperficialValidation.validateElement(testClassElement)).isFalse();
+          }
+        })
+        .failsToCompile();
+  }
+
+  @Test
+  public void missingGrandparentSuperclass() {
+    JavaFileObject javaFileObject = JavaFileObjects.forSourceLines(
+        "test.TestClass",
+        "package test;",
+        "",
+        "class Parent extends Missing {}",
+        "",
+        "class TestClass extends Parent {}");
+    assertAbout(javaSource())
+        .that(javaFileObject)
+        .processedWith(new AssertingProcessor() {
+          @Override
+          void runAssertions() {
+            TypeElement testClassElement =
+                processingEnv.getElementUtils().getTypeElement("test.TestClass");
+            assertThat(SuperficialValidation.validateElement(testClassElement)).isFalse();
+          }
+        })
+        .failsToCompile();
+  }
+
+  @Test
+  public void missingGrandparentSuperinterface() {
+    JavaFileObject javaFileObject = JavaFileObjects.forSourceLines(
+        "test.TestClass",
+        "package test;",
+        "",
+        "interface Parent extends Missing {}",
+        "",
+        "class TestClass implements Parent {}");
+    assertAbout(javaSource())
+        .that(javaFileObject)
+        .processedWith(new AssertingProcessor() {
+          @Override
+          void runAssertions() {
+            TypeElement testClassElement =
+                processingEnv.getElementUtils().getTypeElement("test.TestClass");
+            assertThat(SuperficialValidation.validateElement(testClassElement)).isFalse();
+          }
+        })
+        .failsToCompile();
+  }
+
   private abstract static class AssertingProcessor extends AbstractProcessor {
     @Override
     public Set<String> getSupportedAnnotationTypes() {