From 7eec3798588243c493791a421e6224680870d0e2 Mon Sep 17 00:00:00 2001
From: Stefan Majewsky <majewsky@gmx.net>
Date: Sat, 11 Jan 2025 12:23:31 +0100
Subject: add options.IsNoneOrZero

Also, add the tests for IsSomeAnd and IsNoneOr that I forgot.
---
 option/option.go      |  2 ++
 option/option_test.go | 21 +++++++++++++++++----
 2 files changed, 19 insertions(+), 4 deletions(-)

(limited to 'option')

diff --git a/option/option.go b/option/option.go
index 992c7b7..39fc56d 100644
--- a/option/option.go
+++ b/option/option.go
@@ -203,6 +203,8 @@ func (o Option[T]) IsSomeAnd(predicate func(T) bool) bool {
 }
 
 // IsNoneOr returns whether the Option is either empty, or contains a value that matches the given predicate.
+//
+// If the predicate compares against the zero value, use options.IsNoneOrZero() instead.
 func (o Option[T]) IsNoneOr(predicate func(T) bool) bool {
 	return !o.isSome || predicate(o.value)
 }
diff --git a/option/option_test.go b/option/option_test.go
index 0fa255f..28e6d49 100644
--- a/option/option_test.go
+++ b/option/option_test.go
@@ -33,11 +33,12 @@ func TestAsSlice(t *testing.T) {
 	AssertEqual(t, Some(42).AsSlice(), []int{42})
 }
 
-func TestFilter(t *testing.T) {
-	isEven := func(x int) bool {
-		return x%2 == 0
-	}
+func isEven(x int) bool {
+	// an example predicate for testing the various functions that take predicates
+	return x%2 == 0
+}
 
+func TestFilter(t *testing.T) {
 	AssertEqual(t, None[int]().Filter(isEven), None[int]())
 	AssertEqual(t, Some(41).Filter(isEven), None[int]())
 	AssertEqual(t, Some(42).Filter(isEven), Some(42))
@@ -48,11 +49,23 @@ func TestIsNone(t *testing.T) {
 	AssertEqual(t, Some(42).IsNone(), false)
 }
 
+func TestIsNoneOr(t *testing.T) {
+	AssertEqual(t, None[int]().IsNoneOr(isEven), true)
+	AssertEqual(t, Some(41).IsNoneOr(isEven), false)
+	AssertEqual(t, Some(42).IsNoneOr(isEven), true)
+}
+
 func TestIsSome(t *testing.T) {
 	AssertEqual(t, None[int]().IsSome(), false)
 	AssertEqual(t, Some(42).IsSome(), true)
 }
 
+func TestIsSomeAnd(t *testing.T) {
+	AssertEqual(t, None[int]().IsSomeAnd(isEven), false)
+	AssertEqual(t, Some(41).IsSomeAnd(isEven), false)
+	AssertEqual(t, Some(42).IsSomeAnd(isEven), true)
+}
+
 func TestIsZero(t *testing.T) {
 	AssertEqual(t, None[int]().IsZero(), true)
 	AssertEqual(t, Some(42).IsZero(), false)
-- 
cgit v1.2.3