Polish "Fix support for default values in banner placeholders"

See gh-34764

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/ResourceBanner.java

@@ -28,11 +28,11 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
 import org.springframework.boot.ansi.AnsiPropertySource;
+import org.springframework.core.env.ConfigurableEnvironment;
 import org.springframework.core.env.Environment;
 import org.springframework.core.env.MapPropertySource;
 import org.springframework.core.env.MutablePropertySources;
 import org.springframework.core.env.PropertyResolver;
-import org.springframework.core.env.PropertySource;
 import org.springframework.core.env.PropertySourcesPropertyResolver;
 import org.springframework.core.io.Resource;
 import org.springframework.core.log.LogMessage;
@@ -79,22 +79,15 @@ public class ResourceBanner implements Banner {
 
 	protected List<PropertyResolver> getPropertyResolvers(Environment environment, Class<?> sourceClass) {
 		MutablePropertySources propertySources = new MutablePropertySources();
-		propertySources.addLast(getEnvironmentSource(environment));
+		if (environment instanceof ConfigurableEnvironment) {
+			((ConfigurableEnvironment) environment).getPropertySources().forEach(propertySources::addLast);
+		}
 		propertySources.addLast(getTitleSource(sourceClass));
 		propertySources.addLast(getAnsiSource());
 		propertySources.addLast(getVersionSource(sourceClass));
 		return Collections.singletonList(new PropertySourcesPropertyResolver(propertySources));
 	}
 
-	private PropertySource<Environment> getEnvironmentSource(Environment environment) {
-		return new PropertySource<Environment>("environment", environment) {
-			@Override
-			public Object getProperty(String name) {
-				return environment.getProperty(name);
-			}
-		};
-	}
-
 	private MapPropertySource getVersionSource(Class<?> sourceClass) {
 		return new MapPropertySource("version", getVersionsMap(sourceClass));
 	}

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/ResourceBannerTests.java

@@ -49,21 +49,6 @@ class ResourceBannerTests {
 		AnsiOutput.setEnabled(Enabled.DETECT);
 	}
 
-	@Test
-	void doNotUseDefaultsIfValueExists() {
-		Resource resource = new ByteArrayResource(
-				"banner ${a:def} ${spring-boot.version:def} ${application.version:def}".getBytes());
-		String banner = printBanner(resource, "10.2", "1.0", null);
-		assertThat(banner).startsWith("banner 1 10.2 1.0");
-	}
-
-	@Test
-	void useDefaults() {
-		Resource resource = new ByteArrayResource("banner ${b:def1} ${c:def2} ${d:def3}".getBytes());
-		String banner = printBanner(resource, null, null, null);
-		assertThat(banner).startsWith("banner def1 def2 def3");
-	}
-
 	@Test
 	void renderVersions() {
 		Resource resource = new ByteArrayResource(
@@ -142,6 +127,15 @@ class ResourceBannerTests {
 		assertThat(banner).startsWith("banner  1");
 	}
 
+	@Test
+	void renderWithDefaultValues() {
+		Resource resource = new ByteArrayResource(
+				"banner ${a:default-a} ${b:default-b} ${spring-boot.version:default-boot-version} ${application.version:default-application-version}"
+					.getBytes());
+		String banner = printBanner(resource, "10.2", "1.0", null);
+		assertThat(banner).startsWith("banner 1 default-b 10.2 1.0");
+	}
+
 	private String printBanner(Resource resource, String bootVersion, String applicationVersion,
 			String applicationTitle) {
 		ResourceBanner banner = new MockResourceBanner(resource, bootVersion, applicationVersion, applicationTitle);