Add nullability annotations to tests in module/spring-boot-liquibase

See gh-47263

module/spring-boot-liquibase/build.gradle

@@ -56,3 +56,11 @@ dependencies {
 	testRuntimeOnly("ch.qos.logback:logback-classic")
 	testRuntimeOnly("org.postgresql:postgresql")
 }
+
+tasks.named("compileTestJava") {
+	options.nullability.checking = "tests"
+}
+
+tasks.named("compileDockerTestJava") {
+	options.nullability.checking = "tests"
+}

module/spring-boot-liquibase/src/test/java/org/springframework/boot/liquibase/LiquibaseChangelogMissingFailureAnalyzerTests.java

@@ -20,6 +20,7 @@ import javax.sql.DataSource;
 
 import com.zaxxer.hikari.HikariDataSource;
 import liquibase.integration.spring.SpringLiquibase;
+import org.jspecify.annotations.Nullable;
 import org.junit.jupiter.api.Test;
 
 import org.springframework.beans.factory.BeanCreationException;
@@ -40,6 +41,7 @@ class LiquibaseChangelogMissingFailureAnalyzerTests {
 	@Test
 	void changelogParseExceptionDueToChangelogNotPresent() {
 		FailureAnalysis analysis = performAnalysis();
+		assertThat(analysis).isNotNull();
 		assertThat(analysis.getDescription())
 			.isEqualTo("Liquibase failed to start because no changelog could be found at '"
 					+ "classpath:/db/changelog/db.changelog-master.yaml'.");
@@ -47,13 +49,13 @@ class LiquibaseChangelogMissingFailureAnalyzerTests {
 			.isEqualTo("Make sure a Liquibase changelog is present at the configured path.");
 	}
 
-	private FailureAnalysis performAnalysis() {
+	private @Nullable FailureAnalysis performAnalysis() {
 		BeanCreationException failure = createFailure();
 		assertThat(failure).isNotNull();
 		return new LiquibaseChangelogMissingFailureAnalyzer().analyze(failure);
 	}
 
-	private BeanCreationException createFailure() {
+	private @Nullable BeanCreationException createFailure() {
 		try (AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(
 				LiquibaseConfiguration.class)) {
 			return null;

module/spring-boot-liquibase/src/test/java/org/springframework/boot/liquibase/autoconfigure/LiquibaseAutoConfigurationTests.java

@@ -25,6 +25,7 @@ import java.lang.annotation.Target;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.sql.Connection;
+import java.sql.Driver;
 import java.sql.SQLException;
 import java.util.Map;
 import java.util.UUID;
@@ -334,7 +335,9 @@ class LiquibaseAutoConfigurationTests {
 			.run(assertLiquibase((liquibase) -> {
 				SimpleDriverDataSource dataSource = (SimpleDriverDataSource) liquibase.getDataSource();
 				assertThat(dataSource.getUrl()).isEqualTo(jdbcUrl);
-				assertThat(dataSource.getDriver().getClass().getName()).isEqualTo("org.h2.Driver");
+				Driver driver = dataSource.getDriver();
+				assertThat(driver).isNotNull();
+				assertThat(driver.getClass().getName()).isEqualTo("org.h2.Driver");
 			}));
 	}
 
@@ -349,7 +352,9 @@ class LiquibaseAutoConfigurationTests {
 			.run(assertLiquibase((liquibase) -> {
 				SimpleDriverDataSource dataSource = (SimpleDriverDataSource) liquibase.getDataSource();
 				assertThat(dataSource.getUrl()).isEqualTo(jdbcUrl);
-				assertThat(dataSource.getDriver().getClass().getName()).isEqualTo(driverClassName);
+				Driver driver = dataSource.getDriver();
+				assertThat(driver).isNotNull();
+				assertThat(driver.getClass().getName()).isEqualTo(driverClassName);
 			}));
 	}