Convert MustacheAutoConfigurationTests to application context runner

Closes gh-30252

Author: wilkinsona

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/mustache/MustacheAutoConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2022 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.
@@ -19,91 +19,71 @@
 import com.samskivert.mustache.Mustache;
 import org.junit.jupiter.api.Test;
 
-import org.springframework.boot.test.util.TestPropertyValues;
-import org.springframework.boot.web.reactive.context.AnnotationConfigReactiveWebApplicationContext;
-import org.springframework.boot.web.servlet.context.AnnotationConfigServletWebApplicationContext;
+import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.test.context.runner.AbstractApplicationContextRunner;
+import org.springframework.boot.test.context.runner.ReactiveWebApplicationContextRunner;
+import org.springframework.boot.test.context.runner.WebApplicationContextRunner;
 import org.springframework.boot.web.servlet.view.MustacheViewResolver;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
-import org.springframework.context.annotation.Import;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
 /**
  * Tests for {@link MustacheAutoConfiguration}.
  *
  * @author Brian Clozel
+ * @author Andy Wilkinson
  */
 class MustacheAutoConfigurationTests {
 
-	private AnnotationConfigServletWebApplicationContext webContext;
-
-	private AnnotationConfigReactiveWebApplicationContext reactiveWebContext;
-
 	@Test
 	void registerBeansForServletApp() {
-		loadWithServlet(null);
-		assertThat(this.webContext.getBeansOfType(Mustache.Compiler.class)).hasSize(1);
-		assertThat(this.webContext.getBeansOfType(MustacheResourceTemplateLoader.class)).hasSize(1);
-		assertThat(this.webContext.getBeansOfType(MustacheViewResolver.class)).hasSize(1);
+		configure(new WebApplicationContextRunner()).run((context) -> {
+			assertThat(context).hasSingleBean(Mustache.Compiler.class);
+			assertThat(context).hasSingleBean(MustacheResourceTemplateLoader.class);
+			assertThat(context).hasSingleBean(MustacheViewResolver.class);
+		});
 	}
 
 	@Test
 	void registerCompilerForServletApp() {
-		loadWithServlet(CustomCompilerConfiguration.class);
-		assertThat(this.webContext.getBeansOfType(MustacheResourceTemplateLoader.class)).hasSize(1);
-		assertThat(this.webContext.getBeansOfType(MustacheViewResolver.class)).hasSize(1);
-		assertThat(this.webContext.getBeansOfType(Mustache.Compiler.class)).hasSize(1);
-		assertThat(this.webContext.getBean(Mustache.Compiler.class).standardsMode).isTrue();
+		configure(new WebApplicationContextRunner()).withUserConfiguration(CustomCompilerConfiguration.class)
+				.run((context) -> {
+					assertThat(context).hasSingleBean(Mustache.Compiler.class);
+					assertThat(context).hasSingleBean(MustacheResourceTemplateLoader.class);
+					assertThat(context).hasSingleBean(MustacheViewResolver.class);
+					assertThat(context.getBean(Mustache.Compiler.class).standardsMode).isTrue();
+				});
 	}
 
 	@Test
 	void registerBeansForReactiveApp() {
-		loadWithReactive(null);
-		assertThat(this.reactiveWebContext.getBeansOfType(Mustache.Compiler.class)).hasSize(1);
-		assertThat(this.reactiveWebContext.getBeansOfType(MustacheResourceTemplateLoader.class)).hasSize(1);
-		assertThat(this.reactiveWebContext.getBeansOfType(MustacheViewResolver.class)).isEmpty();
-		assertThat(this.reactiveWebContext
-				.getBeansOfType(org.springframework.boot.web.reactive.result.view.MustacheViewResolver.class))
-						.hasSize(1);
+		configure(new ReactiveWebApplicationContextRunner()).run((context) -> {
+			assertThat(context).hasSingleBean(Mustache.Compiler.class);
+			assertThat(context).hasSingleBean(MustacheResourceTemplateLoader.class);
+			assertThat(context).doesNotHaveBean(MustacheViewResolver.class);
+			assertThat(context)
+					.hasSingleBean(org.springframework.boot.web.reactive.result.view.MustacheViewResolver.class);
+		});
 	}
 
 	@Test
 	void registerCompilerForReactiveApp() {
-		loadWithReactive(CustomCompilerConfiguration.class);
-		assertThat(this.reactiveWebContext.getBeansOfType(Mustache.Compiler.class)).hasSize(1);
-		assertThat(this.reactiveWebContext.getBeansOfType(MustacheResourceTemplateLoader.class)).hasSize(1);
-		assertThat(this.reactiveWebContext.getBeansOfType(MustacheViewResolver.class)).isEmpty();
-		assertThat(this.reactiveWebContext
-				.getBeansOfType(org.springframework.boot.web.reactive.result.view.MustacheViewResolver.class))
-						.hasSize(1);
-		assertThat(this.reactiveWebContext.getBean(Mustache.Compiler.class).standardsMode).isTrue();
-	}
-
-	private void loadWithServlet(Class<?> config) {
-		this.webContext = new AnnotationConfigServletWebApplicationContext();
-		TestPropertyValues.of("spring.mustache.prefix=classpath:/mustache-templates/").applyTo(this.webContext);
-		if (config != null) {
-			this.webContext.register(config);
-		}
-		this.webContext.register(BaseConfiguration.class);
-		this.webContext.refresh();
+		configure(new ReactiveWebApplicationContextRunner()).withUserConfiguration(CustomCompilerConfiguration.class)
+				.run((context) -> {
+					assertThat(context).hasSingleBean(Mustache.Compiler.class);
+					assertThat(context).hasSingleBean(MustacheResourceTemplateLoader.class);
+					assertThat(context).doesNotHaveBean(MustacheViewResolver.class);
+					assertThat(context).hasSingleBean(
+							org.springframework.boot.web.reactive.result.view.MustacheViewResolver.class);
+					assertThat(context.getBean(Mustache.Compiler.class).standardsMode).isTrue();
+				});
 	}
 
-	private void loadWithReactive(Class<?> config) {
-		this.reactiveWebContext = new AnnotationConfigReactiveWebApplicationContext();
-		TestPropertyValues.of("spring.mustache.prefix=classpath:/mustache-templates/").applyTo(this.reactiveWebContext);
-		if (config != null) {
-			this.reactiveWebContext.register(config);
-		}
-		this.reactiveWebContext.register(BaseConfiguration.class);
-		this.reactiveWebContext.refresh();
-	}
-
-	@Configuration(proxyBeanMethods = false)
-	@Import({ MustacheAutoConfiguration.class })
-	static class BaseConfiguration {
-
+	private <T extends AbstractApplicationContextRunner<T, ?, ?>> T configure(T runner) {
+		return runner.withPropertyValues("spring.mustache.prefix=classpath:/mustache-templates/")
+				.withConfiguration(AutoConfigurations.of(MustacheAutoConfiguration.class));
 	}
 
 	@Configuration(proxyBeanMethods = false)