Polish "Fix NPE in FlywayEndpoint when migration.installedOn is null"

Closes gh-14019

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/flyway/FlywayEndpoint.java

@@ -168,18 +168,17 @@ public class FlywayEndpoint {
 			this.installedBy = info.getInstalledBy();
 			this.installedRank = info.getInstalledRank();
 			this.executionTime = info.getExecutionTime();
-			this.installedOn = toEpochMilli(info.getInstalledOn());
-		}
-
-		private Instant toEpochMilli(Date installedOn) {
-			return (installedOn != null) ? Instant.ofEpochMilli(installedOn.getTime())
-					: null;
+			this.installedOn = nullSafeToInstant(info.getInstalledOn());
 		}
 
 		private String nullSafeToString(Object obj) {
 			return (obj != null) ? obj.toString() : null;
 		}
 
+		private Instant nullSafeToInstant(Date date) {
+			return (date != null) ? Instant.ofEpochMilli(date.getTime()) : null;
+		}
+
 		public MigrationType getType() {
 			return this.type;
 		}

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/flyway/FlywayEndpointTests.java

@@ -16,9 +16,13 @@
 
 package org.springframework.boot.actuate.flyway;
 
+import java.util.Map;
+
 import org.junit.Test;
 
+import org.springframework.boot.actuate.flyway.FlywayEndpoint.FlywayDescriptor;
 import org.springframework.boot.autoconfigure.flyway.FlywayAutoConfiguration;
+import org.springframework.boot.autoconfigure.flyway.FlywayMigrationStrategy;
 import org.springframework.boot.autoconfigure.jdbc.EmbeddedDataSourceConfiguration;
 import org.springframework.boot.test.context.runner.ApplicationContextRunner;
 import org.springframework.context.ApplicationContext;
@@ -40,9 +44,28 @@ public class FlywayEndpointTests {
 	@Test
 	public void flywayReportIsProduced() {
 		new ApplicationContextRunner().withUserConfiguration(Config.class)
-				.run((context) -> assertThat(
-						context.getBean(FlywayEndpoint.class).flywayBeans().getContexts()
-								.get(context.getId()).getFlywayBeans()).hasSize(1));
+				.run((context) -> {
+					Map<String, FlywayDescriptor> flywayBeans = context
+							.getBean(FlywayEndpoint.class).flywayBeans().getContexts()
+							.get(context.getId()).getFlywayBeans();
+					assertThat(flywayBeans).hasSize(1);
+					assertThat(flywayBeans.values().iterator().next().getMigrations())
+							.hasSize(3);
+				});
+	}
+
+	@Test
+	public void whenFlywayHasBeenBaselinedFlywayReportIsProduced() {
+		new ApplicationContextRunner()
+				.withUserConfiguration(BaselinedFlywayConfig.class, Config.class)
+				.run((context) -> {
+					Map<String, FlywayDescriptor> flywayBeans = context
+							.getBean(FlywayEndpoint.class).flywayBeans().getContexts()
+							.get(context.getId()).getFlywayBeans();
+					assertThat(flywayBeans).hasSize(1);
+					assertThat(flywayBeans.values().iterator().next().getMigrations())
+							.hasSize(3);
+				});
 	}
 
 	@Configuration
@@ -56,4 +79,18 @@ public class FlywayEndpointTests {
 
 	}
 
+	@Configuration
+	public static class BaselinedFlywayConfig {
+
+		@Bean
+		public FlywayMigrationStrategy baseliningMigrationStrategy() {
+			return (flyway) -> {
+				flyway.setBaselineVersionAsString("2");
+				flyway.baseline();
+				flyway.migrate();
+			};
+		}
+
+	}
+
 }