Apply TestTypeExcludeFilter in regular applications

Add `ExcludeFilterApplicationContextInitializer` to register the
`TestTypeExcludeFilter` for regular applications.

Prior to this commit, the filter was only registered using the
`ExcludeFilterContextCustomizerFactory` which meant that test components
were filtered in tests but not when using `SpringApplication.from` with
a test classpath.

Fixes spring-projectsgh-35206

spring-boot-project/spring-boot-test/src/main/java/org/springframework/boot/test/context/filter/ExcludeFilterApplicationContextInitializer.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2012-2023 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.filter;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.context.ConfigurableApplicationContext;
+
+/**
+ * {@link ApplicationContextInitializer} to register the {@link TestTypeExcludeFilter} for
+ * when {@link SpringApplication#from} is being used with the test classpath.
+ *
+ * @author Phillip Webb
+ */
+class ExcludeFilterApplicationContextInitializer
+		implements ApplicationContextInitializer<ConfigurableApplicationContext> {
+
+	@Override
+	public void initialize(ConfigurableApplicationContext applicationContext) {
+		TestTypeExcludeFilter.registerWith(applicationContext.getBeanFactory());
+	}
+
+}

spring-boot-project/spring-boot-test/src/main/java/org/springframework/boot/test/context/filter/ExcludeFilterContextCustomizer.java

@@ -32,7 +32,7 @@ class ExcludeFilterContextCustomizer implements ContextCustomizer {
 	@Override
 	public void customizeContext(ConfigurableApplicationContext context,
 			MergedContextConfiguration mergedContextConfiguration) {
-		context.getBeanFactory().registerSingleton(TestTypeExcludeFilter.class.getName(), new TestTypeExcludeFilter());
+		TestTypeExcludeFilter.registerWith(context.getBeanFactory());
 	}
 
 	@Override

spring-boot-project/spring-boot-test/src/main/java/org/springframework/boot/test/context/filter/TestTypeExcludeFilter.java

@@ -18,6 +18,7 @@
 
 import java.io.IOException;
 
+import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.boot.context.TypeExcludeFilter;
 import org.springframework.boot.test.context.TestComponent;
 import org.springframework.core.type.classreading.MetadataReader;
@@ -32,13 +33,17 @@
  */
 class TestTypeExcludeFilter extends TypeExcludeFilter {
 
+	private static final String BEAN_NAME = TestTypeExcludeFilter.class.getName();
+
 	private static final String[] CLASS_ANNOTATIONS = { "org.junit.runner.RunWith",
 			"org.junit.jupiter.api.extension.ExtendWith", "org.junit.platform.commons.annotation.Testable",
 			"org.testng.annotations.Test" };
 
 	private static final String[] METHOD_ANNOTATIONS = { "org.junit.Test",
 			"org.junit.platform.commons.annotation.Testable", "org.testng.annotations.Test" };
 
+	private static final TestTypeExcludeFilter INSTANCE = new TestTypeExcludeFilter();
+
 	@Override
 	public boolean match(MetadataReader metadataReader, MetadataReaderFactory metadataReaderFactory)
 			throws IOException {
@@ -91,4 +96,10 @@ private boolean isTestClass(MetadataReader metadataReader) {
 		return false;
 	}
 
+	static void registerWith(ConfigurableListableBeanFactory beanFactory) {
+		if (!beanFactory.containsSingleton(BEAN_NAME)) {
+			beanFactory.registerSingleton(BEAN_NAME, INSTANCE);
+		}
+	}
+
 }

spring-boot-project/spring-boot-test/src/main/resources/META-INF/spring.factories

@@ -16,3 +16,7 @@ org.springframework.boot.test.mock.mockito.ResetMocksTestExecutionListener
 # Environment Post Processors
 org.springframework.boot.env.EnvironmentPostProcessor=\
 org.springframework.boot.test.web.SpringBootTestRandomPortEnvironmentPostProcessor
+
+# Application Context Initializers
+org.springframework.context.ApplicationContextInitializer=\
+org.springframework.boot.test.context.filter.ExcludeFilterApplicationContextInitializer

spring-boot-project/spring-boot-test/src/test/java/org/springframework/boot/test/context/filter/ExcludeFilterApplicationContextInitializerTests.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright 2012-2023 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.filter;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.WebApplicationType;
+import org.springframework.boot.context.TypeExcludeFilter;
+import org.springframework.boot.test.context.TestConfiguration;
+import org.springframework.boot.test.context.assertj.AssertableApplicationContext;
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.ComponentScan.Filter;
+import org.springframework.context.annotation.FilterType;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests {@link ExcludeFilterApplicationContextInitializer}.
+ *
+ * @author Phillip Webb
+ */
+class ExcludeFilterApplicationContextInitializerTests {
+
+	@Test
+	void testConfigurationIsExcluded() {
+		SpringApplication application = new SpringApplication(TestApplication.class);
+		application.setWebApplicationType(WebApplicationType.NONE);
+		AssertableApplicationContext applicationContext = AssertableApplicationContext.get(() -> application.run());
+		assertThat(applicationContext).hasSingleBean(TestApplication.class);
+		assertThat(applicationContext).doesNotHaveBean(ExcludedTestConfiguration.class);
+	}
+
+	@ComponentScan(excludeFilters = { @Filter(type = FilterType.CUSTOM, classes = TypeExcludeFilter.class) })
+	static class TestApplication {
+
+	}
+
+	@TestConfiguration(proxyBeanMethods = false)
+	static class ExcludedTestConfiguration {
+
+	}
+
+}