all: replace deprecated io/ioutil calls

The io/ioutil package's features were moved to
the io and os packages in Go 1.16.

x/net depends on Go 1.18. Drop ioutil calls,
so gopls doesn't warn about them.

Change-Id: Ibdb576d94f250808ae285aa142e2fd41e7e9afc9
Reviewed-on: https://go-review.googlesource.com/c/net/+/586244
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Ian Lance Taylor <[email protected]>

Author: neild

bpf/instructions_test.go

@@ -6,7 +6,7 @@ package bpf
 
 import (
 	"fmt"
-	"io/ioutil"
+	"os"
 	"reflect"
 	"strconv"
 	"strings"
@@ -98,7 +98,7 @@ func TestInterop(t *testing.T) {
 	}
 	t.Logf("Assembled program is %d instructions long", len(out))
 
-	bs, err := ioutil.ReadFile(allInstructionsExpected)
+	bs, err := os.ReadFile(allInstructionsExpected)
 	if err != nil {
 		t.Fatalf("reading %s: %s", allInstructionsExpected, err)
 	}

context/ctxhttp/ctxhttp_test.go

@@ -9,7 +9,6 @@ package ctxhttp
 import (
 	"context"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -49,7 +48,7 @@ func TestNoTimeout(t *testing.T) {
 		t.Fatal(err)
 	}
 	defer res.Body.Close()
-	slurp, err := ioutil.ReadAll(res.Body)
+	slurp, err := io.ReadAll(res.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -102,7 +101,7 @@ func TestCancelAfterHangingRequest(t *testing.T) {
 	done := make(chan struct{})
 
 	go func() {
-		b, err := ioutil.ReadAll(resp.Body)
+		b, err := io.ReadAll(resp.Body)
 		if len(b) != 0 || err == nil {
 			t.Errorf(`Read got (%q, %v); want ("", error)`, b, err)
 		}

dns/dnsmessage/message_test.go

@@ -7,7 +7,7 @@ package dnsmessage
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"reflect"
 	"strings"
@@ -1611,7 +1611,7 @@ func TestNoFmt(t *testing.T) {
 		// Could use something complex like go/build or x/tools/go/packages,
 		// but there's no reason for "fmt" to appear (in quotes) in the source
 		// otherwise, so just use a simple substring search.
-		data, err := ioutil.ReadFile(file)
+		data, err := os.ReadFile(file)
 		if err != nil {
 			t.Fatal(err)
 		}

html/atom/gen.go

@@ -14,7 +14,6 @@ import (
 	"flag"
 	"fmt"
 	"go/format"
-	"io/ioutil"
 	"math/rand"
 	"os"
 	"sort"
@@ -48,7 +47,7 @@ func genFile(name string, buf *bytes.Buffer) {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}
-	if err := ioutil.WriteFile(name, b, 0644); err != nil {
+	if err := os.WriteFile(name, b, 0644); err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}

html/charset/charset_test.go

@@ -7,7 +7,8 @@ package charset
 import (
 	"bytes"
 	"encoding/xml"
-	"io/ioutil"
+	"io"
+	"os"
 	"runtime"
 	"strings"
 	"testing"
@@ -17,7 +18,7 @@ import (
 
 func transformString(t transform.Transformer, s string) (string, error) {
 	r := transform.NewReader(strings.NewReader(s), t)
-	b, err := ioutil.ReadAll(r)
+	b, err := io.ReadAll(r)
 	return string(b), err
 }
 
@@ -142,7 +143,7 @@ func TestSniff(t *testing.T) {
 	}
 
 	for _, tc := range sniffTestCases {
-		content, err := ioutil.ReadFile("testdata/" + tc.filename)
+		content, err := os.ReadFile("testdata/" + tc.filename)
 		if err != nil {
 			t.Errorf("%s: error reading file: %v", tc.filename, err)
 			continue
@@ -163,7 +164,7 @@ func TestReader(t *testing.T) {
 	}
 
 	for _, tc := range sniffTestCases {
-		content, err := ioutil.ReadFile("testdata/" + tc.filename)
+		content, err := os.ReadFile("testdata/" + tc.filename)
 		if err != nil {
 			t.Errorf("%s: error reading file: %v", tc.filename, err)
 			continue
@@ -175,14 +176,14 @@ func TestReader(t *testing.T) {
 			continue
 		}
 
-		got, err := ioutil.ReadAll(r)
+		got, err := io.ReadAll(r)
 		if err != nil {
 			t.Errorf("%s: error reading from charset.NewReader: %v", tc.filename, err)
 			continue
 		}
 
 		e, _ := Lookup(tc.want)
-		want, err := ioutil.ReadAll(transform.NewReader(bytes.NewReader(content), e.NewDecoder()))
+		want, err := io.ReadAll(transform.NewReader(bytes.NewReader(content), e.NewDecoder()))
 		if err != nil {
 			t.Errorf("%s: error decoding with hard-coded charset name: %v", tc.filename, err)
 			continue

html/parse_test.go

@@ -10,7 +10,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"runtime"
@@ -477,7 +476,7 @@ func TestParseFragmentForeignContentTemplates(t *testing.T) {
 }
 
 func BenchmarkParser(b *testing.B) {
-	buf, err := ioutil.ReadFile("testdata/go1.html")
+	buf, err := os.ReadFile("testdata/go1.html")
 	if err != nil {
 		b.Fatalf("could not read testdata/go1.html: %v", err)
 	}

html/token_test.go

@@ -7,7 +7,7 @@ package html
 import (
 	"bytes"
 	"io"
-	"io/ioutil"
+	"os"
 	"reflect"
 	"runtime"
 	"strings"
@@ -680,7 +680,7 @@ tests:
 				}
 			}
 			// Anything tokenized along with untokenized input or data left in the reader.
-			assembled, err := ioutil.ReadAll(io.MultiReader(&tokenized, bytes.NewReader(z.Buffered()), r))
+			assembled, err := io.ReadAll(io.MultiReader(&tokenized, bytes.NewReader(z.Buffered()), r))
 			if err != nil {
 				t.Errorf("%s: ReadAll: %v", test.desc, err)
 				continue tests
@@ -866,7 +866,7 @@ const (
 )
 
 func benchmarkTokenizer(b *testing.B, level int) {
-	buf, err := ioutil.ReadFile("testdata/go1.html")
+	buf, err := os.ReadFile("testdata/go1.html")
 	if err != nil {
 		b.Fatalf("could not read testdata/go1.html: %v", err)
 	}

http2/h2c/h2c_test.go

@@ -9,7 +9,6 @@ import (
 	"crypto/tls"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"net"
 	"net/http"
@@ -68,7 +67,7 @@ func TestContext(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	_, err = ioutil.ReadAll(resp.Body)
+	_, err = io.ReadAll(resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -162,7 +161,7 @@ func TestMaxBytesHandler(t *testing.T) {
 		t.Fatal(err)
 	}
 	defer resp.Body.Close()
-	_, err = ioutil.ReadAll(resp.Body)
+	_, err = io.ReadAll(resp.Body)
 	if err != nil {
 		t.Fatal(err)
 	}

http2/hpack/gen.go

@@ -10,7 +10,6 @@ import (
 	"bytes"
 	"fmt"
 	"go/format"
-	"io/ioutil"
 	"os"
 	"sort"
 
@@ -176,7 +175,7 @@ func genFile(name string, buf *bytes.Buffer) {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}
-	if err := ioutil.WriteFile(name, b, 0644); err != nil {
+	if err := os.WriteFile(name, b, 0644); err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}

http2/http2_test.go

@@ -8,7 +8,6 @@ import (
 	"bytes"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"net/http"
 	"os"
 	"path/filepath"
@@ -266,7 +265,7 @@ func TestNoUnicodeStrings(t *testing.T) {
 			return nil
 		}
 
-		contents, err := ioutil.ReadFile(path)
+		contents, err := os.ReadFile(path)
 		if err != nil {
 			t.Fatal(err)
 		}