Replace deprecated ioutil functions with go 1.16.

.github/workflows/pr_test.yml

@@ -9,7 +9,7 @@ jobs:
     - name: Install Go
       uses: actions/setup-go@v2
       with:
-        go-version: 1.14.x
+        go-version: 1.16.x
     - name: Restore cache
       id: cache
       uses: actions/cache@v1
@@ -48,7 +48,7 @@ jobs:
   test:
     strategy:
       matrix:
-        go-version: [1.14.x]
+        go-version: [1.16.x]
         node-version: [12]
         rust-toolchain: [1.49.0]
         platform: [ubuntu-latest, macos-latest, windows-latest]

.github/workflows/tag_release.yml

@@ -14,7 +14,7 @@ jobs:
     - name: Install Go
       uses: actions/setup-go@v2
       with:
-        go-version: '1.14.x'
+        go-version: '1.16.x'
     - name: Install Ruby
       uses: actions/setup-ruby@v1
       with:

README.md

@@ -122,7 +122,7 @@ eval "$(fastly --completion-script-zsh)"
 
 ## Development
 
-The Fastly CLI requires [Go 1.13 or above](https://golang.org). Clone this repo
+The Fastly CLI requires [Go 1.16 or above](https://golang.org). Clone this repo
 to any path and type `make` to run all of the tests and generate a development
 build locally.
 

go.mod

@@ -1,6 +1,6 @@
 module github.com/fastly/cli
 
-go 1.14
+go 1.16
 
 require (
 	github.com/BurntSushi/toml v0.3.1

go.sum

@@ -36,15 +36,13 @@ github.com/fastly/kingpin v2.1.12-0.20191105091915-95d230a53780+incompatible h1:
 github.com/fastly/kingpin v2.1.12-0.20191105091915-95d230a53780+incompatible/go.mod h1:U8UynVoU1SQaqD2I4ZqgYd5lx3A1ipQYn4aSt2Y5h6c=
 github.com/fatih/color v1.7.0 h1:DkWD4oS2D8LGGgTQ6IvwJJXSL5Vp2ffcQg58nFV38Ys=
 github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
-github.com/flynn/go-shlex v0.0.0-20150515145356-3f9db97f8568 h1:BHsljHzVlRcyQhjrss6TZTdY2VfCqZPbv5k3iBFa2ZQ=
 github.com/flynn/go-shlex v0.0.0-20150515145356-3f9db97f8568/go.mod h1:xEzjJPgXI435gkrCt3MPfRiAkVrwSbHsst4LCFVfpJc=
 github.com/frankban/quicktest v1.5.0 h1:Tb4jWdSpdjKzTUicPnY61PZxKbDoGa7ABbrReT3gQVY=
 github.com/frankban/quicktest v1.5.0/go.mod h1:jaStnuzAqU1AJdCO0l53JDCJrVDKcS03DbaAcR7Ks/o=
 github.com/gliderlabs/ssh v0.2.2 h1:6zsha5zo/TWhRhwqCD3+EarCAgZ2yN28ipRnGPnwkI0=
 github.com/gliderlabs/ssh v0.2.2/go.mod h1:U7qILu1NlMHj9FlMhZLlkCdDnU1DBEAqr0aevW3Awn0=
 github.com/golang/gddo v0.0.0-20190419222130-af0f2af80721 h1:KRMr9A3qfbVM7iV/WcLY/rL5LICqwMHLhwRXKu99fXw=
 github.com/golang/gddo v0.0.0-20190419222130-af0f2af80721/go.mod h1:xEhNfoBDX1hzLm2Nf80qUvZ2sVwoMZ8d6IE2SrsQfh4=
-github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/snappy v0.0.1 h1:Qgr9rKW7uDUkrbSmQeiDsGa8SjGyCOGtuasMWwvp2P4=
 github.com/golang/snappy v0.0.1/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
@@ -135,13 +133,11 @@ github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9de
 golang.org/x/crypto v0.0.0-20190219172222-a4c6cb3142f2/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20190510104115-cbcb75029529/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
-golang.org/x/crypto v0.0.0-20190701094942-4def268fd1a4 h1:HuIa8hRrWRSrqYzx1qI49NNxhdi2PrY7gxVSq1JjLDc=
 golang.org/x/crypto v0.0.0-20190701094942-4def268fd1a4/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9 h1:psW17arqaxU48Z5kZ0CQnkZWQJsqcURM6tKiBApRjXI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/mod v0.0.0-20190513183733-4bf6d317e70e/go.mod h1:mXi4GBBbnImb6dmsKGUJ2LatrhH/nqhxcFungHvyanc=
-golang.org/x/mod v0.2.0 h1:KU7oHjnv3XNWfa5COkzUifxZmxp1TyI7ImMXqFxLwvQ=
 golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
@@ -152,36 +148,30 @@ golang.org/x/net v0.0.0-20201021035429-f5854403a974 h1:IX6qOQeG5uLjB/hjjwjedwfjN
 golang.org/x/net v0.0.0-20201021035429-f5854403a974/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/sync v0.0.0-20190227155943-e225da77a7e6/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.0.0-20190423024810-112230192c58 h1:8gQV6CLnAEikrhgkHFbMAEhagSSnXWGV915qUMm9mrU=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190221075227-b4e8571b14e0/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20190726091711-fc99dfbffb4e h1:D5TXcfTk7xF7hvieo4QErS3qqCB4teTffacDWr7CI+0=
 golang.org/x/sys v0.0.0-20190726091711-fc99dfbffb4e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f h1:+Nyd8tzPX9R7BWHguqsrbFdRx3WQ/1ib8I44HXV5yTA=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
-golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/text v0.3.3 h1:cokOdA+Jmi5PJGXLlLllQSgYigAEfHXJAERHVMaCc2k=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20190729092621-ff9f1409240a/go.mod h1:jcCCGcm9btYwXyDqrUWc6MKQKKGJCWEQ3AfLSRIbEuI=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20191130070609-6e064ea0cf2d/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
-golang.org/x/tools v0.0.0-20200624163319-25775e59acb7 h1:LqJsVIMDZN3D7MG8O2vT+ClouLDqeK3YkClIcDzImVs=
 golang.org/x/tools v0.0.0-20200624163319-25775e59acb7/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
@@ -196,9 +186,7 @@ gopkg.in/warnings.v0 v0.1.2 h1:wFXVbFY8DY5/xOe1ECiWdKCzZlxgshcYVNkBHstARME=
 gopkg.in/warnings.v0 v0.1.2/go.mod h1:jksf8JmL6Qr/oQM2OXTHunEvvTAsrWBLb6OOjuVWRNI=
 gopkg.in/yaml.v2 v2.0.0-20170812160011-eb3733d160e7/go.mod h1:JAlM8MvJe8wmxCU4Bli9HhUf9+ttbYbLASfIpnQbh74=
 gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
-gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.3.0 h1:clyUAQHOM3G0M3f5vQj7LuJrETvjVot3Z5el9nffUtU=
 gopkg.in/yaml.v2 v2.3.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
-honnef.co/go/tools v0.0.1-2020.1.4 h1:UoveltGrhghAA7ePc+e+QYDHXrBps2PqFZiHkGR/xK8=
 honnef.co/go/tools v0.0.1-2020.1.4/go.mod h1:X/FiERA/W4tHapMX5mGpAtMSVEeEUOyHaw9vFzvIQ3k=

pkg/app/run.go

@@ -5,7 +5,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"regexp"
 	"time"
@@ -87,7 +86,7 @@ func Run(args []string, env config.Environment, file config.File, configFilePath
 	// bindings, because we need to do things like track where a config
 	// parameter came from.
 	app := kingpin.New("fastly", "A tool to interact with the Fastly API")
-	app.Writers(out, ioutil.Discard) // don't let kingpin write error output
+	app.Writers(out, io.Discard) // don't let kingpin write error output
 	app.UsageContext(&kingpin.UsageContext{
 		Template: VerboseUsageTemplate,
 		Funcs:    UsageTemplateFuncs,
@@ -617,17 +616,17 @@ func Run(args []string, env config.Environment, file config.File, configFilePath
 	// swapping the writer with a no-op and then restoring the real writer
 	// afterwards. This ensures usage text is only written once to the writer
 	// and gives us greater control over our error formatting.
-	app.Writers(ioutil.Discard, ioutil.Discard)
+	app.Writers(io.Discard, io.Discard)
 	name, err := app.Parse(args)
 	if err != nil && !argsIsHelpJSON(args) { // Ignore error if `help --format json`
-		usage := Usage(args, app, out, ioutil.Discard)
+		usage := Usage(args, app, out, io.Discard)
 		return errors.RemediationError{Prefix: usage, Inner: fmt.Errorf("error parsing arguments: %w", err)}
 	}
 	if ctx, _ := app.ParseContext(args); contextHasHelpFlag(ctx) {
-		usage := Usage(args, app, out, ioutil.Discard)
+		usage := Usage(args, app, out, io.Discard)
 		return errors.RemediationError{Prefix: usage}
 	}
-	app.Writers(out, ioutil.Discard)
+	app.Writers(out, io.Discard)
 
 	// As the `help` command model gets privately added as a side-effect of
 	// kingping.Parse, we cannot add the `--format json` flag to the model.
@@ -649,9 +648,9 @@ func Run(args []string, env config.Environment, file config.File, configFilePath
 	// larger and more verbose help formatting is used.
 	if name == "help" {
 		var buf bytes.Buffer
-		app.Writers(&buf, ioutil.Discard)
+		app.Writers(&buf, io.Discard)
 		app.Parse(args)
-		app.Writers(out, ioutil.Discard)
+		app.Writers(out, io.Discard)
 
 		// The full-fat output of `fastly help` should have a hint at the bottom
 		// for more specific help. Unfortunately I don't know of a better way to
@@ -720,7 +719,7 @@ func Run(args []string, env config.Environment, file config.File, configFilePath
 
 	command, found := common.SelectCommand(name, commands)
 	if !found {
-		usage := Usage(args, app, out, ioutil.Discard)
+		usage := Usage(args, app, out, io.Discard)
 		return errors.RemediationError{Prefix: usage, Inner: fmt.Errorf("command not found")}
 	}
 

pkg/app/usage.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"encoding/json"
 	"io"
-	"io/ioutil"
 	"strings"
 	"text/template"
 
@@ -91,7 +90,7 @@ func UsageJSON(app *kingpin.Application) (string, error) {
 // re-assigned to the app via app.Writers after calling Usage.
 func Usage(args []string, app *kingpin.Application, out, err io.Writer) string {
 	var buf bytes.Buffer
-	app.Writers(&buf, ioutil.Discard)
+	app.Writers(&buf, io.Discard)
 	app.UsageContext(&kingpin.UsageContext{
 		Template: CompactUsageTemplate,
 		Funcs:    UsageTemplateFuncs,

pkg/compute/compute_integration_test.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"os"
@@ -349,7 +348,7 @@ func TestInit(t *testing.T) {
 				testutil.AssertStringContains(t, buf.String(), s)
 			}
 			if testcase.manifestIncludes != "" {
-				content, err := ioutil.ReadFile(filepath.Join(rootdir, compute.ManifestFilename))
+				content, err := os.ReadFile(filepath.Join(rootdir, compute.ManifestFilename))
 				if err != nil {
 					t.Fatal(err)
 				}
@@ -885,7 +884,7 @@ func TestDeploy(t *testing.T) {
 				testutil.AssertStringContains(t, buf.String(), s)
 			}
 			if testcase.manifestIncludes != "" {
-				content, err := ioutil.ReadFile(filepath.Join(rootdir, compute.ManifestFilename))
+				content, err := os.ReadFile(filepath.Join(rootdir, compute.ManifestFilename))
 				if err != nil {
 					t.Fatal(err)
 				}
@@ -1028,7 +1027,7 @@ func TestValidate(t *testing.T) {
 func makeInitEnvironment(t *testing.T, manifestContent string) (rootdir string) {
 	t.Helper()
 
-	rootdir, err := ioutil.TempDir("", "fastly-init-*")
+	rootdir, err := os.MkdirTemp("", "fastly-init-*")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -1039,7 +1038,7 @@ func makeInitEnvironment(t *testing.T, manifestContent string) (rootdir string)
 
 	if manifestContent != "" {
 		filename := filepath.Join(rootdir, compute.ManifestFilename)
-		if err := ioutil.WriteFile(filename, []byte(manifestContent), 0777); err != nil {
+		if err := os.WriteFile(filename, []byte(manifestContent), 0777); err != nil {
 			t.Fatal(err)
 		}
 	}
@@ -1050,7 +1049,7 @@ func makeInitEnvironment(t *testing.T, manifestContent string) (rootdir string)
 func makeRustBuildEnvironment(t *testing.T, fastlyManifestContent, cargoManifestContent, cargoLockContent string) (rootdir string) {
 	t.Helper()
 
-	rootdir, err := ioutil.TempDir("", "fastly-build-*")
+	rootdir, err := os.MkdirTemp("", "fastly-build-*")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -1071,21 +1070,21 @@ func makeRustBuildEnvironment(t *testing.T, fastlyManifestContent, cargoManifest
 
 	if fastlyManifestContent != "" {
 		filename := filepath.Join(rootdir, compute.ManifestFilename)
-		if err := ioutil.WriteFile(filename, []byte(fastlyManifestContent), 0777); err != nil {
+		if err := os.WriteFile(filename, []byte(fastlyManifestContent), 0777); err != nil {
 			t.Fatal(err)
 		}
 	}
 
 	if cargoManifestContent != "" {
 		filename := filepath.Join(rootdir, "Cargo.toml")
-		if err := ioutil.WriteFile(filename, []byte(cargoManifestContent), 0777); err != nil {
+		if err := os.WriteFile(filename, []byte(cargoManifestContent), 0777); err != nil {
 			t.Fatal(err)
 		}
 	}
 
 	if cargoLockContent != "" {
 		filename := filepath.Join(rootdir, "Cargo.lock")
-		if err := ioutil.WriteFile(filename, []byte(cargoLockContent), 0777); err != nil {
+		if err := os.WriteFile(filename, []byte(cargoLockContent), 0777); err != nil {
 			t.Fatal(err)
 		}
 	}
@@ -1096,7 +1095,7 @@ func makeRustBuildEnvironment(t *testing.T, fastlyManifestContent, cargoManifest
 func makeAssemblyScriptBuildEnvironment(t *testing.T, fastlyManifestContent string) (rootdir string) {
 	t.Helper()
 
-	rootdir, err := ioutil.TempDir("", "fastly-build-*")
+	rootdir, err := os.MkdirTemp("", "fastly-build-*")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -1116,7 +1115,7 @@ func makeAssemblyScriptBuildEnvironment(t *testing.T, fastlyManifestContent stri
 
 	if fastlyManifestContent != "" {
 		filename := filepath.Join(rootdir, compute.ManifestFilename)
-		if err := ioutil.WriteFile(filename, []byte(fastlyManifestContent), 0777); err != nil {
+		if err := os.WriteFile(filename, []byte(fastlyManifestContent), 0777); err != nil {
 			t.Fatal(err)
 		}
 	}
@@ -1133,7 +1132,7 @@ func makeAssemblyScriptBuildEnvironment(t *testing.T, fastlyManifestContent stri
 func makeDeployEnvironment(t *testing.T, manifestContent string) (rootdir string) {
 	t.Helper()
 
-	rootdir, err := ioutil.TempDir("", "fastly-deploy-*")
+	rootdir, err := os.MkdirTemp("", "fastly-deploy-*")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -1152,7 +1151,7 @@ func makeDeployEnvironment(t *testing.T, manifestContent string) (rootdir string
 
 	if manifestContent != "" {
 		filename := filepath.Join(rootdir, compute.ManifestFilename)
-		if err := ioutil.WriteFile(filename, []byte(manifestContent), 0777); err != nil {
+		if err := os.WriteFile(filename, []byte(manifestContent), 0777); err != nil {
 			t.Fatal(err)
 		}
 	}

pkg/compute/compute_test.go

@@ -4,7 +4,6 @@ import (
 	"crypto/rand"
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"os"
@@ -481,7 +480,7 @@ func makeBuildEnvironment(t *testing.T, fastlyIgnoreContent string) (rootdir str
 
 	if fastlyIgnoreContent != "" {
 		filename := filepath.Join(rootdir, IgnoreFilePath)
-		if err := ioutil.WriteFile(filename, []byte(fastlyIgnoreContent), 0777); err != nil {
+		if err := os.WriteFile(filename, []byte(fastlyIgnoreContent), 0777); err != nil {
 			t.Fatal(err)
 		}
 	}

pkg/compute/rust.go

@@ -5,7 +5,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"os"
 	"os/exec"
@@ -376,7 +375,7 @@ func getLatestCrateVersion(client api.HTTPClient, name string) (*semver.Version,
 		return nil, fmt.Errorf("error fetching latest crate version: %s", resp.Status)
 	}
 
-	body, err := ioutil.ReadAll(resp.Body)
+	body, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return nil, err
 	}

pkg/configure/configure_test.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"errors"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"os"
 	"strings"
@@ -214,7 +213,7 @@ func TestConfigure(t *testing.T) {
 				testutil.AssertStringContains(t, out.String(), s)
 			}
 			if testcase.wantError == "" {
-				p, err := ioutil.ReadFile(configFilePath)
+				p, err := os.ReadFile(configFilePath)
 				testutil.AssertNoError(t, err)
 				testutil.AssertString(t, strings.Join(testcase.wantFile, "\n")+"\n", string(p))
 			}

pkg/edgedictionaryitem/batch.go

@@ -4,7 +4,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 
 	"github.com/fastly/cli/pkg/common"
@@ -49,7 +48,7 @@ func (c *BatchCommand) Exec(in io.Reader, out io.Writer) error {
 		return err
 	}
 
-	jsonBytes, err := ioutil.ReadAll(jsonFile)
+	jsonBytes, err := io.ReadAll(jsonFile)
 	if err != nil {
 		return err
 	}

pkg/logs/tail.go

@@ -7,7 +7,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/url"
 	"os"
@@ -216,7 +215,7 @@ func (c *TailCommand) tail(out io.Writer) {
 
 			// Reuse the connection for the retry, or cleanup in the
 			// case of Exit.
-			io.Copy(ioutil.Discard, resp.Body)
+			io.Copy(io.Discard, resp.Body)
 			resp.Body.Close()
 
 			// Try the response again after a 1 second wait.