reflect/protoreflect: clarify Clear and Remove operation on missing entries
Follow the precedence of Go maps where deletion on a key without an entry in
the map is a noop. Similarly, document that the following methods are safe
to call with entries that do not exist:
* Map.Clear
* KnownFields.Clear
* ExtensionFieldTypes.Remove
Change the implementation for each of these to match the documented behavior.
Change-Id: Ifccff9b7b03baaeffdc366d05f6286ba60e14934
Reviewed-on: https://go-review.googlesource.com/c/148317
Reviewed-by: Herbie Ong <herbie@google.com>
diff --git a/internal/impl/message.go b/internal/impl/message.go
index a3e4b9d..c406b3d 100644
--- a/internal/impl/message.go
+++ b/internal/impl/message.go
@@ -310,8 +310,8 @@
func (emptyUnknownFields) Len() int { return 0 }
func (emptyUnknownFields) Get(pref.FieldNumber) pref.RawFields { return nil }
-func (emptyUnknownFields) Set(pref.FieldNumber, pref.RawFields) { /* noop */ }
-func (emptyUnknownFields) Range(func(pref.FieldNumber, pref.RawFields) bool) {}
+func (emptyUnknownFields) Set(pref.FieldNumber, pref.RawFields) { return } // noop
+func (emptyUnknownFields) Range(func(pref.FieldNumber, pref.RawFields) bool) { return }
func (emptyUnknownFields) IsSupported() bool { return false }
type emptyExtensionFields struct{}
@@ -319,17 +319,17 @@
func (emptyExtensionFields) Len() int { return 0 }
func (emptyExtensionFields) Has(pref.FieldNumber) bool { return false }
func (emptyExtensionFields) Get(pref.FieldNumber) pref.Value { return pref.Value{} }
-func (emptyExtensionFields) Set(pref.FieldNumber, pref.Value) { panic("invalid field") }
-func (emptyExtensionFields) Clear(pref.FieldNumber) { panic("invalid field") }
-func (emptyExtensionFields) Mutable(pref.FieldNumber) pref.Mutable { panic("invalid field") }
-func (emptyExtensionFields) Range(f func(pref.FieldNumber, pref.Value) bool) {}
+func (emptyExtensionFields) Set(pref.FieldNumber, pref.Value) { panic("extensions not supported") }
+func (emptyExtensionFields) Clear(pref.FieldNumber) { return } // noop
+func (emptyExtensionFields) Mutable(pref.FieldNumber) pref.Mutable { panic("extensions not supported") }
+func (emptyExtensionFields) Range(f func(pref.FieldNumber, pref.Value) bool) { return }
func (emptyExtensionFields) ExtensionTypes() pref.ExtensionFieldTypes { return emptyExtensionTypes{} }
type emptyExtensionTypes struct{}
func (emptyExtensionTypes) Len() int { return 0 }
func (emptyExtensionTypes) Register(pref.ExtensionType) { panic("extensions not supported") }
-func (emptyExtensionTypes) Remove(pref.ExtensionType) { panic("extensions not supported") }
+func (emptyExtensionTypes) Remove(pref.ExtensionType) { return } // noop
func (emptyExtensionTypes) ByNumber(pref.FieldNumber) pref.ExtensionType { return nil }
func (emptyExtensionTypes) ByName(pref.FullName) pref.ExtensionType { return nil }
-func (emptyExtensionTypes) Range(func(pref.ExtensionType) bool) {}
+func (emptyExtensionTypes) Range(func(pref.ExtensionType) bool) { return }