📰 Throw when unregistered feature is queried in tests

chrome/android/junit/src/org/chromium/chrome/browser/EnableFeatures.java

-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-package org.chromium.chrome.browser;
-
-import org.chromium.testing.local.AnnotationProcessor;
-
-import java.lang.annotation.ElementType;
-import java.lang.annotation.Inherited;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
-import java.lang.annotation.Target;
-import java.util.Arrays;
-import java.util.HashSet;
-import java.util.Set;
-
-/**
- * Annotation used to set Feature flags during JUnit tests. To have an effect, the associated
- * {@link Processor} rule needs to be registered on the test class.
- *
- * Sample code:
- *
- * <pre>
- * public class Test {
- *    &#64;Rule
- *    public EnableFeatures.Processor processor = new EnableFeatures.Processor();
- *
- *    &#64;EnableFeatures(ChromeFeatureList.NTP_SNIPPETS_OFFLINE_BADGE)
- *    public void testFoo() { ... }
- * }
- * </pre>
- */
-@Inherited
-@Retention(RetentionPolicy.RUNTIME)
-@Target({ElementType.METHOD, ElementType.TYPE})
-public @interface EnableFeatures {
-
-    String[] value();
-
-    /**
-     * Add this rule to tests to activate the {@link EnableFeatures} annotations and choose flags
-     * to enable, or get rid of exceptions when the production code tries to check for enabled
-     * features.
-     */
-    public static class Processor extends AnnotationProcessor<EnableFeatures> {
-        public Processor() {
-            super(EnableFeatures.class);
-        }
-
-        @Override
-        protected void before() throws Throwable {
-            Set<String> enabledFeatures = new HashSet<>();
-            String[] values = getAnnotation().value();
-            enabledFeatures.addAll(Arrays.asList(values));
-            ChromeFeatureList.setTestEnabledFeatures(enabledFeatures);
-        }
-
-        @Override
-        protected void after() {
-            ChromeFeatureList.setTestEnabledFeatures(null);
-        }
-    }
-}