rename asLeftOptional to optionalList

Author: h908714124

src/main/java/io/jbock/util/Either.java

@@ -87,7 +87,7 @@ public static <L, R> Either<L, R> right(R value) {
      * @return an {@code Optional} which is empty if and only if {@code failures}
      *         is empty
      */
-    public static <L> Optional<List<L>> asLeftOptional(List<? extends L> failures) {
+    public static <L> Optional<List<L>> optionalList(List<? extends L> failures) {
         if (failures.isEmpty()) {
             return Optional.empty();
         }

src/test/java/io/jbock/util/EitherTest.java

@@ -4,6 +4,7 @@
 import org.junit.jupiter.api.Test;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Objects;
 import java.util.Optional;
 
@@ -134,4 +135,11 @@ void testOrElseThrow() {
         Either<String, String> right = Either.right("2");
         assertEquals("2", right.orElseThrow(IllegalArgumentException::new));
     }
+
+    @Test
+    void testOptionalList() {
+        assertEquals(Optional.empty(), Either.optionalList(List.of()));
+        assertEquals(Optional.of(List.of(1)), Either.optionalList(List.of(1)));
+        assertEquals(Optional.of(List.of("1", "2")), Either.optionalList(List.of("1", "2")));
+    }
 }