fixup! Fixes mockito#2626 : Introduce MockSettings.mockMaker

src/test/java/org/mockitointegration/DeferMockMakersClassLoadingTest.java

@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2019 Mockito contributors
+ * This program is made available under the terms of the MIT License.
+ */
+package org.mockitointegration;
+
+import static org.mockito.Mockito.withSettings;
+import static org.mockitoutil.ClassLoaders.coverageTool;
+
+import java.lang.reflect.Method;
+
+import org.assertj.core.api.Assertions;
+import org.hamcrest.Matcher;
+import org.junit.Test;
+import org.mockito.Mockito;
+import org.mockito.internal.creation.bytebuddy.ByteBuddyMockMaker;
+import org.mockito.internal.creation.bytebuddy.InlineByteBuddyMockMaker;
+import org.mockito.internal.creation.bytebuddy.SubclassByteBuddyMockMaker;
+import org.mockito.internal.creation.proxy.ProxyMockMaker;
+import org.mockito.invocation.MockHandler;
+import org.mockito.mock.MockCreationSettings;
+import org.mockito.plugins.MockMaker;
+import org.mockitoutil.ClassLoaders;
+
+public class DeferMockMakersClassLoadingTest {
+    private static final Object MY_MOCK = new Object();
+
+    @Test
+    public void mockito_should_not_load_mock_makers_it_does_not_need() throws Exception {
+        ClassLoader classLoader_without_mockMakers =
+                ClassLoaders.excludingClassLoader()
+                        .withCodeSourceUrlOf(
+                                Mockito.class,
+                                Matcher.class,
+                                CustomMockMaker.class,
+                                Assertions.class)
+                        .withCodeSourceUrlOf(coverageTool())
+                        .without(
+                                ByteBuddyMockMaker.class.getName(),
+                                SubclassByteBuddyMockMaker.class.getName(),
+                                InlineByteBuddyMockMaker.class.getName(),
+                                ProxyMockMaker.class.getName())
+                        .build();
+
+        ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader();
+        Thread.currentThread().setContextClassLoader(classLoader_without_mockMakers);
+        try {
+            Class<?> self = classLoader_without_mockMakers.loadClass(getClass().getName());
+            Method createMock = self.getMethod("createMock");
+            createMock.invoke(null);
+        } finally {
+            Thread.currentThread().setContextClassLoader(contextClassLoader);
+        }
+    }
+
+    // Called by reflection from the test method
+    public static void createMock() {
+        Assertions.assertThat(
+                        Mockito.mock(
+                                Object.class,
+                                withSettings().mockMaker(CustomMockMaker.class.getName())))
+                .isSameAs(MY_MOCK);
+    }
+
+    public static class CustomMockMaker implements MockMaker {
+        @Override
+        public <T> T createMock(MockCreationSettings<T> settings, MockHandler handler) {
+            return settings.getTypeToMock().cast(MY_MOCK);
+        }
+
+        @Override
+        public MockHandler getHandler(Object mock) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public void resetMock(Object mock, MockHandler newHandler, MockCreationSettings settings) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public TypeMockability isTypeMockable(Class<?> type) {
+            return new TypeMockability() {
+                @Override
+                public boolean mockable() {
+                    return type.equals(Object.class);
+                }
+
+                @Override
+                public String nonMockableReason() {
+                    return mockable() ? "" : "type != Object.class";
+                }
+            };
+        }
+    }
+}