| // Copyright 2018 The Bazel Authors. All rights reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package com.google.devtools.build.lib.skylark; |
| |
| import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable; |
| import com.google.devtools.build.lib.skylarkinterface.SkylarkInterfaceUtils; |
| import com.google.devtools.build.lib.skylarkinterface.SkylarkModule; |
| import com.google.devtools.build.lib.util.Classpath; |
| import java.lang.reflect.Method; |
| import org.junit.Test; |
| import org.junit.runner.RunWith; |
| import org.junit.runners.JUnit4; |
| |
| /** |
| * Tests that bazel usages of {@link SkylarkCallable} and {@link SkylarkModule} abide by the |
| * contracts specified in their documentation. |
| * |
| * <p>Tests in this class use the java reflection API.</p> |
| * |
| * <p>This verification *would* be done via annotation processor, but annotation processors in |
| * java don't have access to the full set of information that the java reflection API has.</p> |
| */ |
| @RunWith(JUnit4.class) |
| public class SkylarkAnnotationContractTest { |
| |
| // Common prefix of packages in bazel that may have classes that implement or extend a |
| // Skylark type. |
| private static final String MODULES_PACKAGE_PREFIX = "com/google/devtools/build"; |
| |
| /** |
| * Verifies that every class in bazel that implements or extends a Skylark type has a clearly |
| * resolvable type. |
| * |
| * <p>If this test fails, it indicates the following error scenario: |
| * |
| * <p>Suppose class A is a subclass of both B and C, where B and C are annotated with |
| * @SkylarkModule annotations (and are thus considered "skylark types"). If B is not a |
| * subclass of C (nor visa versa), then it's impossible to resolve whether A is of type |
| * B or if A is of type C. It's both! The way to resolve this is usually to have A be its own |
| * type (annotated with @SkylarkModule), and thus have the explicit type of A be semantically |
| * "B and C". |
| */ |
| @Test |
| public void testResolvableSkylarkModules() throws Exception { |
| for (Class<?> candidateClass : Classpath.findClasses(MODULES_PACKAGE_PREFIX)) { |
| SkylarkInterfaceUtils.getSkylarkModule(candidateClass); |
| } |
| } |
| |
| /** |
| * Verifies that no class or interface has a method annotated with {@link SkylarkCallable} unless |
| * that class or interface is annotated with either {@link SkylarkGlobalLibrary} or with |
| * {@link SkylarkModule}. |
| */ |
| @Test |
| public void testSkylarkCallableScope() throws Exception { |
| for (Class<?> candidateClass : Classpath.findClasses(MODULES_PACKAGE_PREFIX)) { |
| if (SkylarkInterfaceUtils.getSkylarkModule(candidateClass) == null |
| && !SkylarkInterfaceUtils.hasSkylarkGlobalLibrary(candidateClass)) { |
| for (Method method : candidateClass.getMethods()) { |
| SkylarkCallable callable = SkylarkInterfaceUtils.getSkylarkCallable(method); |
| if (callable != null && method.getDeclaringClass() == candidateClass) { |
| throw new AssertionError(String.format( |
| "Class %s has a SkylarkCallable method %s but is neither a @SkylarkModule nor a " |
| + "@SkylarkGlobalLibrary", |
| candidateClass, |
| method.getName())); |
| } |
| } |
| } |
| } |
| } |
| } |