Remove occurrences of ioutil from codebase (#2514)

ioutil is deprecated. Remove it.

internal/contentcache/contentcache_test.go

@@ -17,7 +17,6 @@ package contentcache_test
 import (
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"sync"
 	"testing"
@@ -76,7 +75,7 @@ func TestReadWriteMetadataCheckpointFile(t *testing.T) {
 	metadataFileName, err := contentCache.WriteMetadataCheckpointFile(objectMetadata.ObjectName, &objectMetadata)
 	AssertEq(err, nil)
 	newObjectMetadata := contentcache.CacheFileObjectMetadata{}
-	contents, err := ioutil.ReadFile(metadataFileName)
+	contents, err := os.ReadFile(metadataFileName)
 	AssertEq(err, nil)
 	err = json.Unmarshal(contents, &newObjectMetadata)
 	AssertEq(err, nil)

internal/fs/all_buckets_test.go

@@ -16,7 +16,6 @@ package fs_test
 
 import (
 	"io"
-	"io/ioutil"
 	"os"
 	"path"
 
@@ -56,13 +55,13 @@ func (t *AllBucketsTest) SetUpTestSuite() {
 ////////////////////////////////////////////////////////////////////////
 
 func (t *AllBucketsTest) BaseDir_Ls() {
-	_, err := ioutil.ReadDir(mntDir)
+	_, err := os.ReadDir(mntDir)
 	ExpectThat(err, Error(HasSubstr("operation not supported")))
 }
 
 func (t *AllBucketsTest) BaseDir_Write() {
 	filename := path.Join(mntDir, "foo")
-	err := ioutil.WriteFile(
+	err := os.WriteFile(
 		filename, []byte("content"), os.FileMode(0644))
 	ExpectThat(err, Error(HasSubstr("input/output error")))
 }
@@ -72,7 +71,7 @@ func (t *AllBucketsTest) BaseDir_Rename() {
 	ExpectThat(err, Error(HasSubstr("operation not supported")))
 
 	filename := path.Join(mntDir + "/bucket-0/foo")
-	err = ioutil.WriteFile(
+	err = os.WriteFile(
 		filename, []byte("content"), os.FileMode(0644))
 	AssertEq(nil, err)
 
@@ -92,7 +91,7 @@ func (t *AllBucketsTest) SingleBucket_ReadAfterWrite() {
 	const contents = "tacoburritoenchilada"
 	AssertEq(
 		nil,
-		ioutil.WriteFile(
+		os.WriteFile(
 			filename,
 			[]byte(contents),
 			os.FileMode(0644)))
@@ -143,7 +142,7 @@ func (t *AllBucketsTest) SingleBucket_ReadAfterWrite() {
 	t.f1 = nil
 
 	// Read back its contents.
-	fileContents, err := ioutil.ReadFile(filename)
+	fileContents, err := os.ReadFile(filename)
 
 	AssertEq(nil, err)
 	ExpectEq("000o111ritoenchilada222", string(fileContents))

internal/fs/caching_test.go

@@ -16,7 +16,6 @@ package fs_test
 
 import (
 	"context"
-	"io/ioutil"
 	"os"
 	"path"
 	"time"
@@ -124,15 +123,15 @@ func (t *CachingTest) FileCreatedRemotely() {
 	ExpectEq(len(contents), fi.Size())
 
 	// And read it.
-	b, err := ioutil.ReadFile(path.Join(mntDir, name))
+	b, err := os.ReadFile(path.Join(mntDir, name))
 	AssertEq(nil, err)
 	ExpectEq(contents, string(b))
 
 	// And overwrite it, and read it back again.
-	err = ioutil.WriteFile(path.Join(mntDir, name), []byte("burrito"), 0500)
+	err = os.WriteFile(path.Join(mntDir, name), []byte("burrito"), 0500)
 	AssertEq(nil, err)
 
-	b, err = ioutil.ReadFile(path.Join(mntDir, name))
+	b, err = os.ReadFile(path.Join(mntDir, name))
 	AssertEq(nil, err)
 	ExpectEq("burrito", string(b))
 }
@@ -143,7 +142,7 @@ func (t *CachingTest) FileChangedRemotely() {
 	var err error
 
 	// Create a file via the file system.
-	err = ioutil.WriteFile(path.Join(mntDir, name), []byte("taco"), 0500)
+	err = os.WriteFile(path.Join(mntDir, name), []byte("taco"), 0500)
 	AssertEq(nil, err)
 
 	// Overwrite the object in GCS.
@@ -169,7 +168,7 @@ func (t *CachingTest) FileChangedRemotely() {
 	ExpectEq(len("burrito"), fi.Size())
 
 	// Reading should work as expected.
-	b, err := ioutil.ReadFile(path.Join(mntDir, name))
+	b, err := os.ReadFile(path.Join(mntDir, name))
 	AssertEq(nil, err)
 	ExpectEq("burrito", string(b))
 }
@@ -254,7 +253,7 @@ func (t *CachingTest) TypeOfNameChanges_LocalModifier() {
 	err = os.Remove(path.Join(mntDir, name))
 	AssertEq(nil, err)
 
-	err = ioutil.WriteFile(path.Join(mntDir, name), []byte("taco"), 0400)
+	err = os.WriteFile(path.Join(mntDir, name), []byte("taco"), 0400)
 	AssertEq(nil, err)
 
 	// All caches should have been updated.
@@ -369,7 +368,7 @@ func (t *CachingWithImplicitDirsTest) SymlinksWork() {
 	fileName := path.Join(mntDir, "foo")
 	const contents = "taco"
 
-	err = ioutil.WriteFile(fileName, []byte(contents), 0400)
+	err = os.WriteFile(fileName, []byte(contents), 0400)
 	AssertEq(nil, err)
 
 	// Create a symlink to it.

internal/fs/foreign_modifications_test.go

@@ -22,7 +22,6 @@ import (
 	"bytes"
 	"context"
 	"io"
-	"io/ioutil"
 	"math/rand"
 	"os"
 	"path"
@@ -500,7 +499,7 @@ func (t *ForeignModsTest) ReadFromFile_Small() {
 	defer func() { AssertEq(nil, f.Close()) }()
 
 	// Read its entire contents.
-	slice, err := ioutil.ReadAll(f)
+	slice, err := io.ReadAll(f)
 	AssertEq(nil, err)
 	ExpectEq("tacoburritoenchilada", string(slice))
 
@@ -649,11 +648,11 @@ func (t *ForeignModsTest) ObjectIsOverwritten_File() {
 	ExpectEq(1, fi.Sys().(*syscall.Stat_t).Nlink)
 
 	// Reading from the old file handle should give the old data.
-	contents, err := ioutil.ReadAll(f1)
+	contents, err := io.ReadAll(f1)
 	AssertEq(nil, err)
 	ExpectEq("taco", string(contents))
 
-	contents, err = ioutil.ReadAll(f2)
+	contents, err = io.ReadAll(f2)
 	AssertEq(nil, err)
 	ExpectEq("burrito", string(contents))
 }
@@ -821,7 +820,7 @@ func (t *ForeignModsTest) Mtime() {
 		Metadata: map[string]string{
 			"gcsfuse_mtime": expected.UTC().Format(time.RFC3339Nano),
 		},
-		Contents: ioutil.NopCloser(strings.NewReader("")),
+		Contents: io.NopCloser(strings.NewReader("")),
 	}
 
 	_, err = bucket.CreateObject(ctx, req)
@@ -845,7 +844,7 @@ func (t *ForeignModsTest) RemoteMtimeChange() {
 			Metadata: map[string]string{
 				"gcsfuse_mtime": time.Now().UTC().Format(time.RFC3339Nano),
 			},
-			Contents: ioutil.NopCloser(strings.NewReader("")),
+			Contents: io.NopCloser(strings.NewReader("")),
 		})
 
 	AssertEq(nil, err)
@@ -885,7 +884,7 @@ func (t *ForeignModsTest) Symlink() {
 		Metadata: map[string]string{
 			"gcsfuse_symlink_target": "bar/baz",
 		},
-		Contents: ioutil.NopCloser(strings.NewReader("")),
+		Contents: io.NopCloser(strings.NewReader("")),
 	}
 
 	_, err = bucket.CreateObject(ctx, req)

internal/fs/fs_test.go

@@ -18,7 +18,6 @@ import (
 	"flag"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"math/rand"
 	"os"
 	"os/signal"
@@ -177,7 +176,7 @@ func (t *fsTest) SetUpTestSuite() {
 	t.serverCfg.DirPerms = dirPerms
 
 	// Set up a temporary directory for mounting.
-	mntDir, err = ioutil.TempDir("", "fs_test")
+	mntDir, err = os.MkdirTemp("", "fs_test")
 	AssertEq(nil, err)
 
 	// Create a file system server.