Function HasExtension

proto/extensions.go:45–69

HasExtension reports whether the extension field is present in m either as an explicitly populated field or as an unknown field.

(m Message, xt *ExtensionDesc)

// HasExtension reports whether the extension field is present in m
// either as an explicitly populated field or as an unknown field.
func HasExtension(m Message, xt *ExtensionDesc) (has bool) {
	mr := MessageReflect(m)
	if mr == nil || !mr.IsValid() {
		return false
	}

	// Check whether any populated known field matches the field number.
	xtd := xt.TypeDescriptor()
	if isValidExtension(mr.Descriptor(), xtd) {
		has = mr.Has(xtd)
	} else {
		mr.Range(func(fd protoreflect.FieldDescriptor, _ protoreflect.Value) bool {
			has = int32(fd.Number()) == xt.Field
			return !has
		})
	}

	// Check whether any unknown field matches the field number.
	for b := mr.GetUnknown(); !has && len(b) > 0; {
		num, _, n := protowire.ConsumeField(b)
		has = int32(num) == xt.Field
		b = b[n:]
	}
	return has
}

// ClearExtension removes the extension field from m
// either as an explicitly populated field or as an unknown field.