Support Go 1.20 Unwrap() []error

.github/workflows/go.yml

@@ -13,9 +13,9 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        go: ["1.18.x", "1.19.x"]
+        go: ["1.19.x", "1.20.x"]
         include:
-        - go: 1.19.x
+        - go: 1.20.x
           latest: true
 
     steps:

CHANGELOG.md

@@ -1,6 +1,11 @@
 Releases
 ========
 
+v1.10.0 (unreleased)
+====================
+
+-   Comply with Go 1.20's multiple-error interface.
+
 v1.9.0 (2022-12-12)
 ===================
 

error.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2017-2021 Uber Technologies, Inc.
+// Copyright (c) 2017-2023 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
@@ -142,7 +142,6 @@ package multierr // import "go.uber.org/multierr"
 
 import (
 	"bytes"
-	"errors"
 	"fmt"
 	"io"
 	"strings"
@@ -239,33 +238,6 @@ func (merr *multiError) Errors() []error {
 	return merr.errors
 }
 
-// As attempts to find the first error in the error list that matches the type
-// of the value that target points to.
-//
-// This function allows errors.As to traverse the values stored on the
-// multierr error.
-func (merr *multiError) As(target interface{}) bool {
-	for _, err := range merr.Errors() {
-		if errors.As(err, target) {
-			return true
-		}
-	}
-	return false
-}
-
-// Is attempts to match the provided error against errors in the error list.
-//
-// This function allows errors.Is to traverse the values stored on the
-// multierr error.
-func (merr *multiError) Is(target error) bool {
-	for _, err := range merr.Errors() {
-		if errors.Is(err, target) {
-			return true
-		}
-	}
-	return false
-}
-
 func (merr *multiError) Error() string {
 	if merr == nil {
 		return ""

error_post_go120.go

@@ -0,0 +1,29 @@
+// Copyright (c) 2017-2023 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
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+//go:build go1.20
+// +build go1.20
+
+package multierr
+
+// Unwrap returns a list of errors wrapped by this multierr.
+func (merr *multiError) Unwrap() []error {
+	return merr.Errors()
+}

error_pre_go120.go

@@ -0,0 +1,59 @@
+// Copyright (c) 2017-2023 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
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+//go:build !go1.20
+// +build !go1.20
+
+package multierr
+
+import "errors"
+
+// Versions of Go before 1.20 did not support the Unwrap() []error method.
+// This provides a similar behavior by implementing the Is(..) and As(..)
+// methods.
+// See the errors.Join proposal for details:
+// https://github.com/golang/go/issues/53435
+
+// As attempts to find the first error in the error list that matches the type
+// of the value that target points to.
+//
+// This function allows errors.As to traverse the values stored on the
+// multierr error.
+func (merr *multiError) As(target interface{}) bool {
+	for _, err := range merr.Errors() {
+		if errors.As(err, target) {
+			return true
+		}
+	}
+	return false
+}
+
+// Is attempts to match the provided error against errors in the error list.
+//
+// This function allows errors.Is to traverse the values stored on the
+// multierr error.
+func (merr *multiError) Is(target error) bool {
+	for _, err := range merr.Errors() {
+		if errors.Is(err, target) {
+			return true
+		}
+	}
+	return false
+}

tools/go.mod

@@ -3,14 +3,14 @@ module go.uber.org/multierr/tools
 go 1.18
 
 require (
-	golang.org/x/lint v0.0.0-20201208152925-83fdc39ff7b5
-	honnef.co/go/tools v0.3.3
+	golang.org/x/lint v0.0.0-20210508222113-6edffad5e616
+	honnef.co/go/tools v0.4.0
 )
 
 require (
-	github.com/BurntSushi/toml v1.0.0 // indirect
-	golang.org/x/exp/typeparams v0.0.0-20220314205449-43aec2f8a4e7 // indirect
-	golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 // indirect
-	golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f // indirect
-	golang.org/x/tools v0.1.12 // indirect
+	github.com/BurntSushi/toml v1.2.1 // indirect
+	golang.org/x/exp/typeparams v0.0.0-20221208152030-732eee02a75a // indirect
+	golang.org/x/mod v0.7.0 // indirect
+	golang.org/x/sys v0.4.0 // indirect
+	golang.org/x/tools v0.5.0 // indirect
 )

tools/go.sum

@@ -1,25 +1,26 @@
-github.com/BurntSushi/toml v1.0.0 h1:dtDWrepsVPfW9H/4y7dDgFc2MBUSeJhlaDtK13CxFlU=
-github.com/BurntSushi/toml v1.0.0/go.mod h1:CxXYINrC8qIiEnFrOxCa7Jy5BFHlXnUU2pbicEuybxQ=
+github.com/BurntSushi/toml v1.2.1 h1:9F2/+DoOYIOksmaJFPw1tGFy1eDnIJXg+UHjuD8lTak=
+github.com/BurntSushi/toml v1.2.1/go.mod h1:CxXYINrC8qIiEnFrOxCa7Jy5BFHlXnUU2pbicEuybxQ=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
-golang.org/x/exp/typeparams v0.0.0-20220314205449-43aec2f8a4e7 h1:mzVEuUhnztMdHb426A1o6cjz5ha6YV3t6zFTBXqSon4=
-golang.org/x/exp/typeparams v0.0.0-20220314205449-43aec2f8a4e7/go.mod h1:AbB0pIl9nAr9wVwH+Z2ZpaocVmF5I4GyWCDIsVjR0bk=
-golang.org/x/lint v0.0.0-20201208152925-83fdc39ff7b5 h1:2M3HP5CCK1Si9FQhwnzYhXdG6DXeebvUHFpre8QvbyI=
-golang.org/x/lint v0.0.0-20201208152925-83fdc39ff7b5/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
+golang.org/x/exp/typeparams v0.0.0-20221208152030-732eee02a75a h1:Jw5wfR+h9mnIYH+OtGT2im5wV1YGGDora5vTv/aa5bE=
+golang.org/x/exp/typeparams v0.0.0-20221208152030-732eee02a75a/go.mod h1:AbB0pIl9nAr9wVwH+Z2ZpaocVmF5I4GyWCDIsVjR0bk=
+golang.org/x/lint v0.0.0-20210508222113-6edffad5e616 h1:VLliZ0d+/avPrXXH+OakdXhpJuEoBZuwh1m2j7U6Iug=
+golang.org/x/lint v0.0.0-20210508222113-6edffad5e616/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
 golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg=
-golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 h1:6zppjxzCulZykYSLyVDYbneBfbaBIQPYMevg0bEwv2s=
-golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
+golang.org/x/mod v0.7.0 h1:LapD9S96VoQRhi/GrNTqeBJFrUjs5UHCAtTlgwA5oZA=
+golang.org/x/mod v0.7.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f h1:v4INt8xihDGvnrfjMDVXGxw9wrfxYyCjk0KbXjhR55s=
-golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.4.0 h1:Zr2JFtRQNX3BCZ8YtxRE9hNJYC8J6I1MVbMg6owUp18=
+golang.org/x/sys v0.4.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20200130002326-2f3ba24bd6e7/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
-golang.org/x/tools v0.1.12 h1:VveCTK38A2rkS8ZqFY25HIDFscX5X9OoEhJd3quQmXU=
-golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
+golang.org/x/tools v0.5.0 h1:+bSpV5HIeWkuvgaMfI3UmKRThoTA5ODJTUd8T17NO+4=
+golang.org/x/tools v0.5.0/go.mod h1:N+Kgy78s5I24c24dU8OfWNEotWjutIs8SnJvn5IDq+k=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-honnef.co/go/tools v0.3.3 h1:oDx7VAwstgpYpb3wv0oxiZlxY+foCpRAwY7Vk6XpAgA=
-honnef.co/go/tools v0.3.3/go.mod h1:jzwdWgg7Jdq75wlfblQxO4neNaFFSvgc1tD5Wv8U0Yw=
+honnef.co/go/tools v0.4.0 h1:lyXVV1c8wUBJRKqI8JgIpT8TW1VDagfYYaxbKa/HoL8=
+honnef.co/go/tools v0.4.0/go.mod h1:36ZgoUOrqOk1GxwHhyryEkq8FQWkUO2xGuSMhUCcdvA=