Add a test case for binding to map with wildcard types

This commit also changes the spring framework version
to use snapshots.

Closes gh-18767

spring-boot-project/spring-boot-dependencies/pom.xml

@@ -165,7 +165,7 @@
 		<snakeyaml.version>1.23</snakeyaml.version>
 		<solr.version>7.7.2</solr.version>
 		<!-- deprecated in favor of "spring-framework.version" -->
-		<spring.version>5.1.12.RELEASE</spring.version>
+		<spring.version>5.1.13.BUILD-SNAPSHOT</spring.version>
 		<spring-amqp.version>2.1.12.RELEASE</spring-amqp.version>
 		<spring-batch.version>4.1.3.RELEASE</spring-batch.version>
 		<spring-cloud-connectors.version>2.0.7.RELEASE</spring-cloud-connectors.version>

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/bind/MapBinderTests.java

@@ -16,6 +16,7 @@
 
 package org.springframework.boot.context.properties.bind;
 
+import java.net.InetAddress;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
@@ -598,6 +599,18 @@ public class MapBinderTests {
 		assertThat(result.getValues()).containsExactly(entry("a", "b"));
 	}
 
+	@Test
+	public void bindToMapWithWildcardShouldConvertToTheRightType() {
+		// gh-18767
+		MockConfigurationPropertySource source = new MockConfigurationPropertySource();
+		source.put("foo.addresses.localhost[0]", "127.0.0.1");
+		source.put("foo.addresses.localhost[1]", "127.0.0.2");
+		this.sources.add(source);
+		MapWithWildcardProperties result = this.binder.bind("foo", Bindable.of(MapWithWildcardProperties.class)).get();
+		assertThat(result.getAddresses().get("localhost").stream().map(InetAddress::getHostAddress))
+				.containsExactly("127.0.0.1", "127.0.0.2");
+	}
+
 	private <K, V> Bindable<Map<K, V>> getMapBindable(Class<K> keyGeneric, ResolvableType valueType) {
 		ResolvableType keyType = ResolvableType.forClass(keyGeneric);
 		return Bindable.of(ResolvableType.forClassWithGenerics(Map.class, keyType, valueType));
@@ -713,4 +726,18 @@ public class MapBinderTests {
 
 	}
 
+	public static class MapWithWildcardProperties {
+
+		private Map<String, ? extends List<? extends InetAddress>> addresses;
+
+		public Map<String, ? extends List<? extends InetAddress>> getAddresses() {
+			return this.addresses;
+		}
+
+		public void setAddresses(Map<String, ? extends List<? extends InetAddress>> addresses) {
+			this.addresses = addresses;
+		}
+
+	}
+
 }