Load configuration from default profiles if no others active

Before this change if no profile is active yaml documents with
spring.profiles=default were loaded, but they are also loaded
if there *is* an active profile which is more of a problem. In
addition if the user chanes the default profile in the
Environmemt Spring Boot ignore that value ("default" is a magic
String).

After this change:

* If no profile is explicitly active, the default profiles from
the Environment are used explicitly
* The default profiles cause properties to be loaded just like
other profiles, so from YAML documents with spring.profiles and
from files in application-default.properties for instance
* The default profiles are not active when any other profile is
* Properties defined in "top-level" YAML documents with no
specific spring.profiles still act as defaults for *all* profiles

Fixes gh-1219, fixes gh-2623

spring-boot/src/main/java/org/springframework/boot/context/config/ConfigFileApplicationListener.java

@@ -322,6 +322,14 @@ public class ConfigFileApplicationListener implements
 				this.profiles.addAll(list);
 			}
 
+			if (this.profiles.isEmpty()) {
+				for (String defaultProfile : this.environment.getDefaultProfiles()) {
+					if (!this.profiles.contains(defaultProfile)) {
+						this.profiles.add(defaultProfile);
+					}
+				}
+			}
+
 			// The default profile for these purposes is represented as null. We add it
 			// last so that it is first out of the queue (active profiles will then
 			// override any settings in the defaults when the list is reversed later).
@@ -376,7 +384,7 @@ public class ConfigFileApplicationListener implements
 				String profile) throws IOException {
 			Resource resource = this.resourceLoader.getResource(location);
 			PropertySource<?> propertySource = null;
-			if (resource != null) {
+			if (resource != null && resource.exists()) {
 				String name = "applicationConfig: [" + location + "]";
 				String group = "applicationConfig: [" + identifier + "]";
 				propertySource = this.propertiesLoader.load(resource, group, name,

spring-boot/src/main/java/org/springframework/boot/yaml/ArrayDocumentMatcher.java

@@ -16,6 +16,7 @@
 
 package org.springframework.boot.yaml;
 
+import java.util.Collections;
 import java.util.Properties;
 import java.util.Set;
 
@@ -49,6 +50,9 @@ public class ArrayDocumentMatcher implements DocumentMatcher {
 		}
 		Set<String> values = StringUtils.commaDelimitedListToSet(properties
 				.getProperty(this.key));
+		if (values.isEmpty()) {
+			values = Collections.singleton("");
+		}
 		for (String pattern : this.patterns) {
 			for (String value : values) {
 				if (value.matches(pattern)) {

spring-boot/src/main/java/org/springframework/boot/yaml/SpringProfileDocumentMatcher.java

@@ -34,7 +34,7 @@ import org.springframework.core.env.Environment;
  */
 public class SpringProfileDocumentMatcher implements DocumentMatcher {
 
-	private static final String[] DEFAULT_PROFILES = new String[] { "default" };
+	private static final String[] DEFAULT_PROFILES = new String[] { "^\\s*$" };
 
 	private String[] activeProfiles = new String[0];
 

spring-boot/src/test/java/org/springframework/boot/context/config/ConfigFileApplicationListenerTests.java

@@ -123,6 +123,15 @@ public class ConfigFileApplicationListenerTests {
 		assertThat(property, equalTo("frompropertiesfile"));
 	}
 
+	@Test
+	public void loadDefaultPropertiesFile() throws Exception {
+		this.environment.setDefaultProfiles("thedefault");
+		this.initializer.setSearchNames("testprofiles");
+		this.initializer.onApplicationEvent(this.event);
+		String property = this.environment.getProperty("the.property");
+		assertThat(property, equalTo("fromdefaultpropertiesfile"));
+	}
+
 	@Test
 	public void loadTwoPropertiesFile() throws Exception {
 		EnvironmentTestUtils.addEnvironment(this.environment, "spring.config.location:"
@@ -243,6 +252,33 @@ public class ConfigFileApplicationListenerTests {
 		assertThat(this.environment.getProperty("my.array"), nullValue(String.class));
 	}
 
+	@Test
+	public void loadProfileEmptySameAsNotSpecified() throws Exception {
+		this.initializer.setSearchNames("testprofilesempty");
+		this.initializer.onApplicationEvent(this.event);
+		String property = this.environment.getProperty("my.property");
+		assertThat(property, equalTo("fromemptyprofile"));
+	}
+
+	@Test
+	public void loadDefaultYamlDocument() throws Exception {
+		this.environment.setDefaultProfiles("thedefault");
+		this.initializer.setSearchNames("testprofilesdocument");
+		this.initializer.onApplicationEvent(this.event);
+		String property = this.environment.getProperty("my.property");
+		assertThat(property, equalTo("fromdefaultprofile"));
+	}
+
+	@Test
+	public void loadDefaultYamlDocumentNotActivated() throws Exception {
+		this.environment.setDefaultProfiles("thedefault");
+		this.environment.setActiveProfiles("other");
+		this.initializer.setSearchNames("testprofilesdocument");
+		this.initializer.onApplicationEvent(this.event);
+		String property = this.environment.getProperty("my.property");
+		assertThat(property, equalTo("fromotherprofile"));
+	}
+
 	@Test
 	public void commandLineWins() throws Exception {
 		this.environment.getPropertySources().addFirst(

spring-boot/src/test/resources/testprofiles-thedefault.properties

+my.property=fromdefaultpropertiesfile
+the.property=fromdefaultpropertiesfile

spring-boot/src/test/resources/testprofilesdocument.yml

+---
+my:
+  property: fromyamlfile
+  other: notempty
+---
+spring:
+  profiles: thedefault
+my:
+  property: fromdefaultprofile
+---
+spring:
+  profiles: other
+my:
+  property: fromotherprofile
\ No newline at end of file

spring-boot/src/test/resources/testprofilesempty.yml

+---
+my:
+  property: fromyamlfile
+  other: notempty
+---
+spring:
+  profiles: 
+my:
+  property: fromemptyprofile
+---
+spring:
+  profiles: other
+my:
+  property: fromotherprofile
\ No newline at end of file