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-rw-r--r--vendor/go.uber.org/multierr/error.go58
1 files changed, 53 insertions, 5 deletions
diff --git a/vendor/go.uber.org/multierr/error.go b/vendor/go.uber.org/multierr/error.go
index de6ce473..04eb9618 100644
--- a/vendor/go.uber.org/multierr/error.go
+++ b/vendor/go.uber.org/multierr/error.go
@@ -1,4 +1,4 @@
-// Copyright (c) 2017 Uber Technologies, Inc.
+// Copyright (c) 2019 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
@@ -33,7 +33,7 @@
// If only two errors are being combined, the Append function may be used
// instead.
//
-// err = multierr.Combine(reader.Close(), writer.Close())
+// err = multierr.Append(reader.Close(), writer.Close())
//
// This makes it possible to record resource cleanup failures from deferred
// blocks with the help of named return values.
@@ -99,8 +99,6 @@ var (
// Separator for single-line error messages.
_singlelineSeparator = []byte("; ")
- _newline = []byte("\n")
-
// Prefix for multi-line messages
_multilinePrefix = []byte("the following errors occurred:")
@@ -132,7 +130,7 @@ type errorGroup interface {
}
// Errors returns a slice containing zero or more errors that the supplied
-// error is composed of. If the error is nil, the returned slice is empty.
+// error is composed of. If the error is nil, a nil slice is returned.
//
// err := multierr.Append(r.Close(), w.Close())
// errors := multierr.Errors(err)
@@ -399,3 +397,53 @@ func Append(left error, right error) error {
errors := [2]error{left, right}
return fromSlice(errors[0:])
}
+
+// AppendInto appends an error into the destination of an error pointer and
+// returns whether the error being appended was non-nil.
+//
+// var err error
+// multierr.AppendInto(&err, r.Close())
+// multierr.AppendInto(&err, w.Close())
+//
+// The above is equivalent to,
+//
+// err := multierr.Append(r.Close(), w.Close())
+//
+// As AppendInto reports whether the provided error was non-nil, it may be
+// used to build a multierr error in a loop more ergonomically. For example:
+//
+// var err error
+// for line := range lines {
+// var item Item
+// if multierr.AppendInto(&err, parse(line, &item)) {
+// continue
+// }
+// items = append(items, item)
+// }
+//
+// Compare this with a verison that relies solely on Append:
+//
+// var err error
+// for line := range lines {
+// var item Item
+// if parseErr := parse(line, &item); parseErr != nil {
+// err = multierr.Append(err, parseErr)
+// continue
+// }
+// items = append(items, item)
+// }
+func AppendInto(into *error, err error) (errored bool) {
+ if into == nil {
+ // We panic if 'into' is nil. This is not documented above
+ // because suggesting that the pointer must be non-nil may
+ // confuse users into thinking that the error that it points
+ // to must be non-nil.
+ panic("misuse of multierr.AppendInto: into pointer must not be nil")
+ }
+
+ if err == nil {
+ return false
+ }
+ *into = Append(*into, err)
+ return true
+}