From 7fb9b8eb3bb548653ed21c3df5cfa30da353ca0e Mon Sep 17 00:00:00 2001
From: David Hoepelman <992153+dhoepelman@users.noreply.github.com>
Date: Mon, 11 Nov 2024 22:12:03 +0100
Subject: [PATCH] Add Validation.ifPresent and Validation.required (#164)

---
 api/konform.api                                           | 2 ++
 src/commonMain/kotlin/io/konform/validation/Validation.kt | 7 +++++++
 2 files changed, 9 insertions(+)

diff --git a/api/konform.api b/api/konform.api
index f0ddaa0..816c64b 100644
--- a/api/konform.api
+++ b/api/konform.api
@@ -98,6 +98,8 @@ public abstract interface class io/konform/validation/ValidationErrors : java/ut
 
 public final class io/konform/validation/ValidationKt {
 	public static final fun flatten (Ljava/util/List;)Lio/konform/validation/Validation;
+	public static final fun ifPresent (Lio/konform/validation/Validation;)Lio/konform/validation/Validation;
+	public static final fun required (Lio/konform/validation/Validation;)Lio/konform/validation/Validation;
 }
 
 public abstract class io/konform/validation/ValidationResult {
diff --git a/src/commonMain/kotlin/io/konform/validation/Validation.kt b/src/commonMain/kotlin/io/konform/validation/Validation.kt
index 2067217..fcc8fae 100644
--- a/src/commonMain/kotlin/io/konform/validation/Validation.kt
+++ b/src/commonMain/kotlin/io/konform/validation/Validation.kt
@@ -1,6 +1,7 @@
 package io.konform.validation
 
 import io.konform.validation.types.EmptyValidation
+import io.konform.validation.types.NullableValidation
 import io.konform.validation.types.ValidateAll
 
 public interface Validation<in T> {
@@ -20,3 +21,9 @@ public fun <T> List<Validation<T>>.flatten(): Validation<T> =
         1 -> first()
         else -> ValidateAll(this)
     }
+
+/** Run a validation only if the actual value is not-null. */
+public fun <T : Any> Validation<T>.ifPresent(): Validation<T?> = NullableValidation(required = false, validation = this)
+
+/** Require a nullable value to actually be present. */
+public fun <T : Any> Validation<T>.required(): Validation<T?> = NullableValidation(required = true, validation = this)