Initial commit

vendor/github.com/cockroachdb/errors/hintdetail/with_hint.go

@@ -0,0 +1,72 @@
+// Copyright 2019 The Cockroach Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+// implied. See the License for the specific language governing
+// permissions and limitations under the License.
+
+package hintdetail
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/cockroachdb/errors/errbase"
+	"github.com/cockroachdb/errors/errorspb"
+	"github.com/gogo/protobuf/proto"
+)
+
+type withHint struct {
+	cause error
+	hint  string
+}
+
+var _ error = (*withHint)(nil)
+var _ ErrorHinter = (*withHint)(nil)
+var _ fmt.Formatter = (*withHint)(nil)
+var _ errbase.Formatter = (*withHint)(nil)
+
+func (w *withHint) ErrorHint() string { return w.hint }
+func (w *withHint) Error() string     { return w.cause.Error() }
+func (w *withHint) Cause() error      { return w.cause }
+func (w *withHint) Unwrap() error     { return w.cause }
+
+func (w *withHint) Format(s fmt.State, verb rune) { errbase.FormatError(w, s, verb) }
+
+func (w *withHint) FormatError(p errbase.Printer) error {
+	if p.Detail() {
+		p.Print(w.hint)
+	}
+	return w.cause
+}
+
+func encodeWithHint(_ context.Context, err error) (string, []string, proto.Message) {
+	w := err.(*withHint)
+	return "", nil, &errorspb.StringPayload{Msg: w.hint}
+}
+
+func decodeWithHint(
+	_ context.Context, cause error, _ string, _ []string, payload proto.Message,
+) error {
+	m, ok := payload.(*errorspb.StringPayload)
+	if !ok {
+		// If this ever happens, this means some version of the library
+		// (presumably future) changed the payload type, and we're
+		// receiving this here. In this case, give up and let
+		// DecodeError use the opaque type.
+		return nil
+	}
+	return &withHint{cause: cause, hint: m.Msg}
+}
+
+func init() {
+	errbase.RegisterWrapperEncoder(errbase.GetTypeKey((*withHint)(nil)), encodeWithHint)
+	errbase.RegisterWrapperDecoder(errbase.GetTypeKey((*withHint)(nil)), decodeWithHint)
+}