surface (feature): Add Surface.isEnum for Scala 3 Enum (#3271)

airframe-surface/src/main/scala-3/wvlet/airframe/surface/Surface.scala

@@ -34,6 +34,11 @@ trait Surface extends Serializable {
   def isMap: Boolean   = classOf[Map[_, _]].isAssignableFrom(rawType)
   def isArray: Boolean = this.isInstanceOf[ArraySurface]
 
+  /**
+    * True if this surface is a Scala3 enum
+    */
+  def isEnum: Boolean = classOf[scala.reflect.Enum].isAssignableFrom(rawType)
+
   def objectFactory: Option[ObjectFactory] = None
   def withOuter(outer: AnyRef): Surface    = this
 }

airframe-surface/src/test/scala-3/wvlet/airframe/surface/Scala3EnumTest.scala

@@ -0,0 +1,32 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package wvlet.airframe.surface
+
+import wvlet.airspec.AirSpec
+import scala.jdk.CollectionConverters.*
+
+object Scala3EnumTest extends AirSpec:
+
+  enum Color:
+    case Red, Green, Blue
+
+  test("scala 3 enum") {
+    val s = Surface.of[Color]
+
+    s.name shouldBe "Color"
+    s.fullName shouldBe "wvlet.airframe.surface.Scala3EnumTest.Color"
+    s.params shouldBe empty
+
+    s.isEnum shouldBe true
+  }