1 files changed, 105 insertions, 0 deletions
diff --git a/vendor/codeberg.org/gruf/go-mangler/v2/method.go b/vendor/codeberg.org/gruf/go-mangler/v2/method.go
new file mode 100644
index 000000000..7a938d6ae
--- /dev/null
+++ b/vendor/codeberg.org/gruf/go-mangler/v2/method.go
@@ -0,0 +1,105 @@
+package mangler
+
+import (
+	"reflect"
+	"unsafe"
+
+	"codeberg.org/gruf/go-xunsafe"
+)
+
+var (
+	// mangleable type for implement checks.
+	mangleableType = reflect.TypeFor[Mangleable]()
+)
+
+type Mangleable interface {
+	Mangle(dst []byte) []byte
+}
+
+// getMethodType returns a *possible* Mangler to handle case
+// of a type that implements any known interface{} types, else nil.
+func getMethodType(t xunsafe.TypeIter) Mangler {
+	switch {
+	case t.Type.Implements(mangleableType):
+		switch t.Type.Kind() {
+		case reflect.Interface:
+			return getInterfaceMangleableType(t)
+		default:
+			return getConcreteMangleableType(t)
+		}
+	default:
+		return nil
+	}
+}
+
+// getInterfaceMangleableType returns a Mangler to handle case of an interface{}
+// type that implements Mangleable{}, i.e. Mangleable{} itself and any superset of.
+func getInterfaceMangleableType(t xunsafe.TypeIter) Mangler {
+	switch t.Indirect() && !t.IfaceIndir() {
+	case true:
+		return func(buf []byte, ptr unsafe.Pointer) []byte {
+			ptr = *(*unsafe.Pointer)(ptr)
+			if ptr == nil || (*xunsafe.Abi_NonEmptyInterface)(ptr).Data == nil {
+				buf = append(buf, '0')
+				return buf
+			}
+			v := *(*Mangleable)(ptr)
+			buf = append(buf, '1')
+			buf = v.Mangle(buf)
+			return buf
+		}
+	case false:
+		return func(buf []byte, ptr unsafe.Pointer) []byte {
+			if ptr == nil || (*xunsafe.Abi_NonEmptyInterface)(ptr).Data == nil {
+				buf = append(buf, '0')
+				return buf
+			}
+			v := *(*Mangleable)(ptr)
+			buf = append(buf, '1')
+			buf = v.Mangle(buf)
+			return buf
+		}
+	default:
+		panic("unreachable")
+	}
+}
+
+// getConcreteMangleableType returns a Manlger to handle case of concrete
+// (i.e. non-interface{}) type that has a Mangleable{} method receiver.
+func getConcreteMangleableType(t xunsafe.TypeIter) Mangler {
+	itab := xunsafe.GetIfaceITab[Mangleable](t.Type)
+	switch {
+	case t.Indirect() && !t.IfaceIndir():
+		return func(buf []byte, ptr unsafe.Pointer) []byte {
+			ptr = *(*unsafe.Pointer)(ptr)
+			if ptr == nil {
+				buf = append(buf, '0')
+				return buf
+			}
+			v := *(*Mangleable)(xunsafe.PackIface(itab, ptr))
+			buf = append(buf, '1')
+			buf = v.Mangle(buf)
+			return buf
+		}
+	case t.Type.Kind() == reflect.Pointer && t.Type.Implements(mangleableType):
+		// if the interface implementation is received by
+		// value type, the pointer type will also support
+		// it but it requires an extra dereference check.
+		return func(buf []byte, ptr unsafe.Pointer) []byte {
+			if ptr == nil {
+				buf = append(buf, '0')
+				return buf
+			}
+			v := *(*Mangleable)(xunsafe.PackIface(itab, ptr))
+			buf = append(buf, '1')
+			buf = v.Mangle(buf)
+			return buf
+		}
+	default:
+		return func(buf []byte, ptr unsafe.Pointer) []byte {
+			v := *(*Mangleable)(xunsafe.PackIface(itab, ptr))
+			buf = v.Mangle(buf)
+			return buf
+		}
+	}
+}