Add Option type

internal/util/option/option.go

@@ -0,0 +1,41 @@
+package option
+
+type Option[T any] struct {
+	hasValue bool
+	value    T
+}
+
+func Some[T any](value T) Option[T] {
+	return Option[T]{
+		hasValue: true,
+		value:    value,
+	}
+}
+
+func None[T any]() Option[T] {
+	return Option[T]{
+		hasValue: false,
+	}
+}
+
+func (o Option[T]) IsSome() bool {
+	return o.hasValue
+}
+
+func (o Option[T]) IsNone() bool {
+	return !o.hasValue
+}
+
+func (o Option[T]) Value() T {
+	if !o.hasValue {
+		panic("Option has no value")
+	}
+	return o.value
+}
+
+func (o Option[T]) ValueOr(defaultValue T) T {
+	if !o.hasValue {
+		return defaultValue
+	}
+	return o.value
+}

internal/util/option/option_test.go

@@ -0,0 +1,54 @@
+package option_test
+
+import (
+	"testing"
+
+	. "git.omicron.one/omicron/linkshare/internal/util/option"
+)
+
+func TestSome(t *testing.T) {
+	opt := Some(42)
+
+	if !opt.IsSome() {
+		t.Error("Expected IsSome() to be true for Some(42)")
+	}
+
+	if opt.IsNone() {
+		t.Error("Expected IsNone() to be false for Some(42)")
+	}
+
+	if opt.Value() != 42 {
+		t.Errorf("Expected Value() to be 42, got %v", opt.Value())
+	}
+
+	if opt.ValueOr(0) != 42 {
+		t.Errorf("Expected ValueOr(0) to be 42, got %v", opt.ValueOr(0))
+	}
+}
+
+func TestNone(t *testing.T) {
+	opt := None[int]()
+
+	if opt.IsSome() {
+		t.Error("Expected IsSome() to be false for None[int]()")
+	}
+
+	if !opt.IsNone() {
+		t.Error("Expected IsNone() to be true for None[int]()")
+	}
+
+	if opt.ValueOr(99) != 99 {
+		t.Errorf("Expected ValueOr(99) to be 99, got %v", opt.ValueOr(99))
+	}
+}
+
+func TestPanic(t *testing.T) {
+	defer func() {
+		if r := recover(); r == nil {
+			t.Error("Expected Value() to panic on None")
+		}
+	}()
+
+	opt := None[string]()
+	_ = opt.Value() // This should panic
+}