Chain predicates in PropertyMapper when methods

Update `PropertyMapper` to correctly combine predicates when repeated
calls are made to `when` and `whenNot`. Prior to this commit, subsequent
invocations would replace the previous predicate.

Fixes gh-17225

Author: ayudovin

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/properties/PropertyMapper.java

@@ -50,6 +50,7 @@
  * {@link Source#toInstance(Function) new instance}.
  *
  * @author Phillip Webb
+ * @author Artsiom Yudovin
  * @since 2.0.0
  */
 public final class PropertyMapper {
@@ -288,7 +289,7 @@ public <R extends T> Source<R> whenInstanceOf(Class<R> target) {
 		 */
 		public Source<T> whenNot(Predicate<T> predicate) {
 			Assert.notNull(predicate, "Predicate must not be null");
-			return new Source<>(this.supplier, predicate.negate());
+			return when(predicate.negate());
 		}
 
 		/**
@@ -299,7 +300,7 @@ public Source<T> whenNot(Predicate<T> predicate) {
 		 */
 		public Source<T> when(Predicate<T> predicate) {
 			Assert.notNull(predicate, "Predicate must not be null");
-			return new Source<>(this.supplier, predicate);
+			return new Source<>(this.supplier, (this.predicate != null) ? this.predicate.and(predicate) : predicate);
 		}
 
 		/**

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

@@ -28,6 +28,7 @@
  * Tests for {@link PropertyMapper}.
  *
  * @author Phillip Webb
+ * @author Artsiom Yudovin
  */
 public class PropertyMapperTests {
 
@@ -190,6 +191,17 @@ public void whenWhenCombinedWithAsUsesSourceValue() {
 		assertThat(source.getCount()).isOne();
 	}
 
+	@Test
+	public void whenWhenValueNotMatchesShouldSupportChainedCalls() {
+		this.map.from("123").when("456"::equals).when("123"::equals).toCall(Assert::fail);
+	}
+
+	@Test
+	public void whenWhenValueMatchesShouldSupportChainedCalls() {
+		String result = this.map.from("123").when((s) -> s.contains("2")).when("123"::equals).toInstance(String::new);
+		assertThat(result).isEqualTo("123");
+	}
+
 	@Test
 	public void alwaysApplyingWhenNonNullShouldAlwaysApplyNonNullToSource() {
 		this.map.alwaysApplyingWhenNonNull().from(() -> null).toCall(Assert::fail);