Inherit enclosing class's configuration in nested tests

Fixes gh-12470

spring-boot-project/spring-boot-test/src/test/java/org/springframework/boot/test/context/nestedtests/InheritedNestedTestConfigurationTests.java

@@ -0,0 +1,107 @@
+/*
+ * Copyright 2012-2020 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 org.springframework.boot.test.context.nestedtests;
+
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.SpringBootConfiguration;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.context.nestedtests.InheritedNestedTestConfigurationTests.ActionPerformer;
+import org.springframework.boot.test.context.nestedtests.InheritedNestedTestConfigurationTests.AppConfiguration;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.context.annotation.Import;
+import org.springframework.stereotype.Component;
+
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
+/**
+ * Tests for nested test configuration when the configuration is inherited from the
+ * enclosing class (the default behaviour).
+ *
+ * @author Andy Wilkinson
+ */
+@SpringBootTest(classes = AppConfiguration.class)
+@Import(ActionPerformer.class)
+class InheritedNestedTestConfigurationTests {
+
+	@MockBean
+	Action action;
+
+	@Autowired
+	ActionPerformer performer;
+
+	@Test
+	void mockWasInvokedOnce() {
+		this.performer.run();
+		verify(this.action, times(1)).perform();
+	}
+
+	@Test
+	void mockWasInvokedTwice() {
+		this.performer.run();
+		this.performer.run();
+		verify(this.action, times(2)).perform();
+	}
+
+	@Nested
+	class InnerTests {
+
+		@Test
+		void mockWasInvokedOnce() {
+			InheritedNestedTestConfigurationTests.this.performer.run();
+			verify(InheritedNestedTestConfigurationTests.this.action, times(1)).perform();
+		}
+
+		@Test
+		void mockWasInvokedTwice() {
+			InheritedNestedTestConfigurationTests.this.performer.run();
+			InheritedNestedTestConfigurationTests.this.performer.run();
+			verify(InheritedNestedTestConfigurationTests.this.action, times(2)).perform();
+		}
+
+	}
+
+	@Component
+	static class ActionPerformer {
+
+		private final Action action;
+
+		ActionPerformer(Action action) {
+			this.action = action;
+		}
+
+		void run() {
+			this.action.perform();
+		}
+
+	}
+
+	public interface Action {
+
+		void perform();
+
+	}
+
+	@SpringBootConfiguration
+	static class AppConfiguration {
+
+	}
+
+}