Polishing tests

1. Improve null safety
2. Replace lambda with method reference

Author: quaff

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/ConfigurationPropertiesBeanTests.java

@@ -197,6 +197,7 @@ void getWhenHasFactoryMethodAndBeanAnnotationFavorsFactoryMethod() throws Throwa
 	void getWhenHasValidatedBeanBindsWithBeanAnnotation() throws Throwable {
 		get(ValidatedBeanConfiguration.class, "validatedBean", (propertiesBean) -> {
 			Validated validated = propertiesBean.asBindTarget().getAnnotation(Validated.class);
+			assertThat(validated).isNotNull();
 			assertThat(validated.value()).containsExactly(BeanGroup.class);
 		});
 	}
@@ -205,6 +206,7 @@ void getWhenHasValidatedBeanBindsWithBeanAnnotation() throws Throwable {
 	void getWhenHasValidatedFactoryMethodBindsWithFactoryMethodAnnotation() throws Throwable {
 		get(ValidatedMethodConfiguration.class, "annotatedBean", (propertiesBean) -> {
 			Validated validated = propertiesBean.asBindTarget().getAnnotation(Validated.class);
+			assertThat(validated).isNotNull();
 			assertThat(validated.value()).containsExactly(FactoryMethodGroup.class);
 		});
 	}
@@ -213,6 +215,7 @@ void getWhenHasValidatedFactoryMethodBindsWithFactoryMethodAnnotation() throws T
 	void getWhenHasValidatedBeanAndFactoryMethodBindsWithFactoryMethodAnnotation() throws Throwable {
 		get(ValidatedMethodAndBeanConfiguration.class, "validatedBean", (propertiesBean) -> {
 			Validated validated = propertiesBean.asBindTarget().getAnnotation(Validated.class);
+			assertThat(validated).isNotNull();
 			assertThat(validated.value()).containsExactly(FactoryMethodGroup.class);
 		});
 	}

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/ConfigurationPropertiesBindExceptionTests.java

@@ -36,6 +36,7 @@ void createFromBeanHasDetails() {
 		ApplicationContext applicationContext = new AnnotationConfigApplicationContext(Example.class);
 		ConfigurationPropertiesBean bean = ConfigurationPropertiesBean.get(applicationContext,
 				applicationContext.getBean(Example.class), "example");
+		assertThat(bean).isNotNull();
 		ConfigurationPropertiesBindException exception = new ConfigurationPropertiesBindException(bean,
 				new IllegalStateException());
 		assertThat(exception.getMessage()).isEqualTo("Error creating bean with name 'example': "

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/ConfigurationPropertiesTests.java

@@ -1197,6 +1197,7 @@ void loadWhenBoundToRandomPropertyPlaceholder() {
 	void boundPropertiesShouldBeRecorded() {
 		load(NestedConfiguration.class, "name=foo", "nested.name=bar");
 		BoundConfigurationProperties bound = BoundConfigurationProperties.get(this.context);
+		assertThat(bound).isNotNull();
 		Set<ConfigurationPropertyName> keys = bound.getAll().keySet();
 		assertThat(keys.stream().map(ConfigurationPropertyName::toString)).contains("name", "nested.name");
 	}

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/PropertyMapperTests.java

@@ -18,11 +18,11 @@
 
 import java.util.function.Supplier;
 
+import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
-import static org.assertj.core.api.Assertions.fail;
 
 /**
  * Tests for {@link PropertyMapper}.
@@ -57,7 +57,7 @@ void fromValueAsIntShouldAdaptValue() {
 
 	@Test
 	void fromValueAlwaysApplyingWhenNonNullShouldAlwaysApplyNonNullToSource() {
-		this.map.alwaysApplyingWhenNonNull().from((String) null).toCall(() -> fail());
+		this.map.alwaysApplyingWhenNonNull().from((String) null).toCall(Assertions::fail);
 	}
 
 	@Test
@@ -101,14 +101,14 @@ void asShouldAdaptSupplier() {
 
 	@Test
 	void whenNonNullWhenSuppliedNullShouldNotMap() {
-		this.map.from(() -> null).whenNonNull().as(String::valueOf).toCall(() -> fail());
+		this.map.from(() -> null).whenNonNull().as(String::valueOf).toCall(Assertions::fail);
 	}
 
 	@Test
 	void whenNonNullWhenSuppliedThrowsNullPointerExceptionShouldNotMap() {
 		this.map.from(() -> {
 			throw new NullPointerException();
-		}).whenNonNull().as(String::valueOf).toCall(() -> fail());
+		}).whenNonNull().as(String::valueOf).toCall(Assertions::fail);
 	}
 
 	@Test
@@ -119,7 +119,7 @@ void whenTrueWhenValueIsTrueShouldMap() {
 
 	@Test
 	void whenTrueWhenValueIsFalseShouldNotMap() {
-		this.map.from(false).whenTrue().toCall(() -> fail());
+		this.map.from(false).whenTrue().toCall(Assertions::fail);
 	}
 
 	@Test
@@ -130,17 +130,17 @@ void whenFalseWhenValueIsFalseShouldMap() {
 
 	@Test
 	void whenFalseWhenValueIsTrueShouldNotMap() {
-		this.map.from(true).whenFalse().toCall(() -> fail());
+		this.map.from(true).whenFalse().toCall(Assertions::fail);
 	}
 
 	@Test
 	void whenHasTextWhenValueIsNullShouldNotMap() {
-		this.map.from(() -> null).whenHasText().toCall(() -> fail());
+		this.map.from(() -> null).whenHasText().toCall(Assertions::fail);
 	}
 
 	@Test
 	void whenHasTextWhenValueIsEmptyShouldNotMap() {
-		this.map.from("").whenHasText().toCall(() -> fail());
+		this.map.from("").whenHasText().toCall(Assertions::fail);
 	}
 
 	@Test
@@ -157,7 +157,7 @@ void whenEqualToWhenValueIsEqualShouldMatch() {
 
 	@Test
 	void whenEqualToWhenValueIsNotEqualShouldNotMatch() {
-		this.map.from("123").whenEqualTo("321").toCall(() -> fail());
+		this.map.from("123").whenEqualTo("321").toCall(Assertions::fail);
 	}
 
 	@Test
@@ -169,7 +169,7 @@ void whenInstanceOfWhenValueIsTargetTypeShouldMatch() {
 	@Test
 	void whenInstanceOfWhenValueIsNotTargetTypeShouldNotMatch() {
 		Supplier<Number> supplier = () -> 123L;
-		this.map.from(supplier).whenInstanceOf(Double.class).toCall(() -> fail());
+		this.map.from(supplier).whenInstanceOf(Double.class).toCall(Assertions::fail);
 	}
 
 	@Test
@@ -180,7 +180,7 @@ void whenWhenValueMatchesShouldMap() {
 
 	@Test
 	void whenWhenValueDoesNotMatchShouldNotMap() {
-		this.map.from("123").when("321"::equals).toCall(() -> fail());
+		this.map.from("123").when("321"::equals).toCall(Assertions::fail);
 	}
 
 	@Test
@@ -198,12 +198,12 @@ void whenWhenCombinedWithAsUsesSourceValue() {
 
 	@Test
 	void alwaysApplyingWhenNonNullShouldAlwaysApplyNonNullToSource() {
-		this.map.alwaysApplyingWhenNonNull().from(() -> null).toCall(() -> fail());
+		this.map.alwaysApplyingWhenNonNull().from(() -> null).toCall(Assertions::fail);
 	}
 
 	@Test
 	void whenWhenValueNotMatchesShouldSupportChainedCalls() {
-		this.map.from("123").when("456"::equals).when("123"::equals).toCall(() -> fail());
+		this.map.from("123").when("456"::equals).when("123"::equals).toCall(Assertions::fail);
 	}
 
 	@Test