Implement noneOrFail zio#4841

tyrcho · Mar 31, 2021 · 5ec9327 · 5ec9327
1 parent 31234be
commit 5ec9327
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diff --git a/core-tests/shared/src/test/scala/zio/ZIOSpec.scala b/core-tests/shared/src/test/scala/zio/ZIOSpec.scala
@@ -1303,6 +1303,41 @@ object ZIOSpec extends ZIOBaseSpec {
         assertM(ZIO.succeed(false).negate)(equalTo(true))
       }
     ),
+    suite("noneOrFailWith")(
+      testM("on None succeeds with Unit") {
+        val option: Option[String]       = None
+        val adaptError: String => String = identity
+        for {
+          value <- ZIO.noneOrFailWith(option, adaptError)
+        } yield {
+          assert(value)(equalTo(()))
+        }
+      },
+      testM("on Some fails") {
+        for {
+          value <- ZIO.noneOrFailWith(Some("value"), (v: String) => v + v).catchAll(e => ZIO.succeed(e))
+        } yield {
+          assert(value)(equalTo("valuevalue"))
+        }
+      } @@ zioTag(errors)
+    ),
+    suite("noneOrFail")(
+      testM("on None succeeds with Unit") {
+        val option: Option[String]       = None
+        for {
+          value <- ZIO.noneOrFail(option)
+        } yield {
+          assert(value)(equalTo(()))
+        }
+      },
+      testM("on Some fails") {
+        for {
+          value <- ZIO.noneOrFail(Some("value")).catchAll(e => ZIO.succeed(e))
+        } yield {
+          assert(value)(equalTo("value"))
+        }
+      } @@ zioTag(errors)
+    ),
     suite("once")(
       testM("returns an effect that will only be executed once") {
         for {

diff --git a/core/shared/src/main/scala/zio/IO.scala b/core/shared/src/main/scala/zio/IO.scala
@@ -730,6 +730,18 @@ object IO {
    */
   val none: UIO[Option[Nothing]] = ZIO.none
 
+  /**
+   * @see See [[zio.ZIO.noneOrFailWith()]]
+   */
+  def noneOrFailWith[E, O](o: Option[O], f: O => E): IO[E, Unit] =
+    ZIO.noneOrFailWith(o, f)
+
+  /**
+   * @see See [[zio.ZIO.noneOrFail()]]
+   */
+  def noneOrFail[E](o: Option[E]): IO[E, Unit] =
+    ZIO.noneOrFail(o)
+
   /**
    *  @see See [[zio.ZIO.not]]
    */

diff --git a/core/shared/src/main/scala/zio/ZIO.scala b/core/shared/src/main/scala/zio/ZIO.scala
@@ -3649,6 +3649,22 @@ object ZIO extends ZIOCompanionPlatformSpecific {
    */
   val none: UIO[Option[Nothing]] = succeedNow(None)
 
+  /**
+   * Lifts an Option into a IO.
+   * If the option is empty it succeeds with Unit.
+   * If the option is defined it fails with the content.
+   */
+  def noneOrFail[E](o: Option[E]): IO[E, Unit] =
+    getOrFailUnit(o).flip
+
+  /**
+   * Lifts an Option into a IO.
+   * If the option is empty it succeeds with Unit.
+   * If the option is defined it fails with an error adapted with f.
+   */
+  def noneOrFailWith[E, O](o: Option[O], f: O => E): IO[E, Unit] =
+    getOrFailUnit(o).flip.mapError(f)
+
   /**
    * Feeds elements of type `A` to a function `f` that returns an effect.
    * Collects all successes and failures in a tupled fashion.