Reinstate leading / in default value for spring.liquibase.change-log

Unfortunately, while redundant for new applications, removing the
leading slash adversely affected existing application upon upgrades as
it caused Liquibase to re-apply every change log.

Closes gh-20177

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/liquibase/LiquibaseEndpointTests.java

@@ -104,10 +104,10 @@ class LiquibaseEndpointTests {
 							.liquibaseBeans().getContexts().get(context.getId()).getLiquibaseBeans();
 					assertThat(liquibaseBeans.get("liquibase").getChangeSets()).hasSize(1);
 					assertThat(liquibaseBeans.get("liquibase").getChangeSets().get(0).getChangeLog())
-							.isEqualTo("classpath:db/changelog/db.changelog-master.yaml");
+							.isEqualTo("classpath:/db/changelog/db.changelog-master.yaml");
 					assertThat(liquibaseBeans.get("liquibaseBackup").getChangeSets()).hasSize(1);
 					assertThat(liquibaseBeans.get("liquibaseBackup").getChangeSets().get(0).getChangeLog())
-							.isEqualTo("classpath:db/changelog/db.changelog-master-backup.yaml");
+							.isEqualTo("classpath:/db/changelog/db.changelog-master-backup.yaml");
 				});
 	}
 
@@ -157,7 +157,7 @@ class LiquibaseEndpointTests {
 
 		private SpringLiquibase createSpringLiquibase(String changeLog, DataSource dataSource) {
 			SpringLiquibase liquibase = new SpringLiquibase();
-			liquibase.setChangeLog("classpath:db/changelog/" + changeLog);
+			liquibase.setChangeLog("classpath:/db/changelog/" + changeLog);
 			liquibase.setShouldRun(true);
 			liquibase.setDataSource(dataSource);
 			return liquibase;

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/liquibase/LiquibaseProperties.java

@@ -37,7 +37,7 @@ public class LiquibaseProperties {
 	/**
 	 * Change log configuration path.
 	 */
-	private String changeLog = "classpath:db/changelog/db.changelog-master.yaml";
+	private String changeLog = "classpath:/db/changelog/db.changelog-master.yaml";
 
 	/**
 	 * Comma-separated list of runtime contexts to use.

spring-boot-project/spring-boot-autoconfigure/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -1105,7 +1105,7 @@
       "name": "liquibase.change-log",
       "type": "java.lang.String",
       "description": "Change log configuration path.",
-      "defaultValue": "classpath:db/changelog/db.changelog-master.yaml",
+      "defaultValue": "classpath:/db/changelog/db.changelog-master.yaml",
       "deprecation": {
         "replacement": "spring.liquibase.change-log",
         "level": "error"

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

@@ -102,7 +102,7 @@ class LiquibaseAutoConfigurationTests {
 	void defaultSpringLiquibase() {
 		this.contextRunner.withUserConfiguration(EmbeddedDataSourceConfiguration.class)
 				.run(assertLiquibase((liquibase) -> {
-					assertThat(liquibase.getChangeLog()).isEqualTo("classpath:db/changelog/db.changelog-master.yaml");
+					assertThat(liquibase.getChangeLog()).isEqualTo("classpath:/db/changelog/db.changelog-master.yaml");
 					assertThat(liquibase.getContexts()).isNull();
 					assertThat(liquibase.getDefaultSchema()).isNull();
 					assertThat(liquibase.isDropFirst()).isFalse();
@@ -112,26 +112,26 @@ class LiquibaseAutoConfigurationTests {
 	@Test
 	void changelogXml() {
 		this.contextRunner.withUserConfiguration(EmbeddedDataSourceConfiguration.class)
-				.withPropertyValues("spring.liquibase.change-log:classpath:db/changelog/db.changelog-override.xml")
+				.withPropertyValues("spring.liquibase.change-log:classpath:/db/changelog/db.changelog-override.xml")
 				.run(assertLiquibase((liquibase) -> assertThat(liquibase.getChangeLog())
-						.isEqualTo("classpath:db/changelog/db.changelog-override.xml")));
+						.isEqualTo("classpath:/db/changelog/db.changelog-override.xml")));
 	}
 
 	@Test
 	void changelogJson() {
 		this.contextRunner.withUserConfiguration(EmbeddedDataSourceConfiguration.class)
-				.withPropertyValues("spring.liquibase.change-log:classpath:db/changelog/db.changelog-override.json")
+				.withPropertyValues("spring.liquibase.change-log:classpath:/db/changelog/db.changelog-override.json")
 				.run(assertLiquibase((liquibase) -> assertThat(liquibase.getChangeLog())
-						.isEqualTo("classpath:db/changelog/db.changelog-override.json")));
+						.isEqualTo("classpath:/db/changelog/db.changelog-override.json")));
 	}
 
 	@Test
 	@EnabledOnJre(JRE.JAVA_8)
 	void changelogSql() {
 		this.contextRunner.withUserConfiguration(EmbeddedDataSourceConfiguration.class)
-				.withPropertyValues("spring.liquibase.change-log:classpath:db/changelog/db.changelog-override.sql")
+				.withPropertyValues("spring.liquibase.change-log:classpath:/db/changelog/db.changelog-override.sql")
 				.run(assertLiquibase((liquibase) -> assertThat(liquibase.getChangeLog())
-						.isEqualTo("classpath:db/changelog/db.changelog-override.sql")));
+						.isEqualTo("classpath:/db/changelog/db.changelog-override.sql")));
 	}
 
 	@Test
@@ -381,7 +381,7 @@ class LiquibaseAutoConfigurationTests {
 		@Bean
 		SpringLiquibase springLiquibase(DataSource dataSource) {
 			SpringLiquibase liquibase = new SpringLiquibase();
-			liquibase.setChangeLog("classpath:db/changelog/db.changelog-master.yaml");
+			liquibase.setChangeLog("classpath:/db/changelog/db.changelog-master.yaml");
 			liquibase.setShouldRun(true);
 			liquibase.setDataSource(dataSource);
 			return liquibase;

spring-boot-tests/spring-boot-smoke-tests/spring-boot-smoke-test-liquibase/src/test/java/smoketest/liquibase/SampleLiquibaseApplicationTests.java

@@ -59,10 +59,10 @@ class SampleLiquibaseApplicationTests {
 		assertThat(output).contains("Successfully acquired change log lock")
 				.contains("Creating database history table with name: PUBLIC.DATABASECHANGELOG")
 				.contains("Table person created")
-				.contains("ChangeSet classpath:db/changelog/db.changelog-master.yaml::1::"
+				.contains("ChangeSet classpath:/db/changelog/db.changelog-master.yaml::1::"
 						+ "marceloverdijk ran successfully")
 				.contains("New row inserted into person")
-				.contains("ChangeSet classpath:db/changelog/"
+				.contains("ChangeSet classpath:/db/changelog/"
 						+ "db.changelog-master.yaml::2::marceloverdijk ran successfully")
 				.contains("Successfully released change log lock");
 	}