all: fix deprecated code and small lint issues detected by staticcheck (

google#3438)

aws/rds/rds.go

@@ -21,7 +21,6 @@ import (
 	"encoding/pem"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 
 	"github.com/google/wire"
@@ -79,7 +78,7 @@ func (cf *CertFetcher) Fetch(ctx context.Context) ([]*x509.Certificate, error) {
 	if resp.StatusCode != http.StatusOK {
 		return nil, fmt.Errorf("fetch RDS certificates: HTTP %s", resp.Status)
 	}
-	pemData, err := ioutil.ReadAll(&io.LimitedReader{R: resp.Body, N: 1 << 20}) // limit to 1MiB
+	pemData, err := io.ReadAll(&io.LimitedReader{R: resp.Body, N: 1 << 20}) // limit to 1MiB
 	if err != nil {
 		return nil, fmt.Errorf("fetch RDS certificates: %v", err)
 	}

azure/azuredb/azuredb.go

@@ -21,7 +21,6 @@ import (
 	"encoding/pem"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 
 	"golang.org/x/net/context/ctxhttp"
@@ -70,7 +69,7 @@ func (cf *CertFetcher) Fetch(ctx context.Context) ([]*x509.Certificate, error) {
 	if resp.StatusCode != http.StatusOK {
 		return nil, fmt.Errorf("fetch Azure certificates: HTTP %s", resp.Status)
 	}
-	pemData, err := ioutil.ReadAll(&io.LimitedReader{R: resp.Body, N: 1 << 20}) // limit to 1MiB
+	pemData, err := io.ReadAll(&io.LimitedReader{R: resp.Body, N: 1 << 20}) // limit to 1MiB
 	if err != nil {
 		return nil, fmt.Errorf("fetch Azure certificates: %v", err)
 	}

blob/blob.go

@@ -70,7 +70,6 @@ import (
 	"fmt"
 	"hash"
 	"io"
-	"io/ioutil"
 	"log"
 	"mime"
 	"net/http"
@@ -732,7 +731,7 @@ func (b *Bucket) ReadAll(ctx context.Context, key string) (_ []byte, err error)
 		return nil, err
 	}
 	defer r.Close()
-	return ioutil.ReadAll(r)
+	return io.ReadAll(r)
 }
 
 // Download writes the content of a blob into an io.Writer w.

blob/drivertest/drivertest.go

@@ -23,7 +23,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"net/http"
 	"net/url"
@@ -2123,34 +2122,49 @@ func testConcurrentWriteAndRead(t *testing.T, newHarness HarnessMaker) {
 
 	var wg sync.WaitGroup
 
+	errs := make(chan error, numKeys)
+
 	// Write all blobs concurrently.
 	for k := 0; k < numKeys; k++ {
 		wg.Add(1)
 		go func(key int) {
 			if err := b.WriteAll(ctx, blobName(key), keyData[key], nil); err != nil {
-				t.Fatal(err)
+				errs <- fmt.Errorf("WriteAll key=%v: %w", key, err)
 			}
 			wg.Done()
 		}(k)
 		defer b.Delete(ctx, blobName(k))
 	}
 	wg.Wait()
 
+	close(errs)
+
+	for err := range errs {
+		t.Fatalf("got error from concurrent blob write: %v", err)
+	}
+
+	errs = make(chan error, numKeys)
+
 	// Read all blobs concurrently and verify that they contain the expected data.
 	for k := 0; k < numKeys; k++ {
 		wg.Add(1)
 		go func(key int) {
 			buf, err := b.ReadAll(ctx, blobName(key))
 			if err != nil {
-				t.Fatal(err)
-			}
-			if !bytes.Equal(buf, keyData[key]) {
-				t.Errorf("read data mismatch for key %d", key)
+				errs <- err
+			} else if !bytes.Equal(buf, keyData[key]) {
+				errs <- fmt.Errorf("read data mismatch for key %d", key)
 			}
 			wg.Done()
 		}(k)
 	}
 	wg.Wait()
+
+	close(errs)
+
+	for err := range errs {
+		t.Fatalf("got error from concurrent blob write: %v", err)
+	}
 }
 
 // testUploadDownload tests that Upload and Download work. For many drivers,
@@ -2275,7 +2289,7 @@ func testKeys(t *testing.T, newHarness HarnessMaker) {
 				if resp.StatusCode != 200 {
 					t.Errorf("got status code %d, want 200", resp.StatusCode)
 				}
-				got, err := ioutil.ReadAll(resp.Body)
+				got, err := io.ReadAll(resp.Body)
 				if err != nil {
 					t.Fatal(err)
 				}
@@ -2463,7 +2477,7 @@ func testSignedURL(t *testing.T, newHarness HarnessMaker) {
 			success := resp.StatusCode >= 200 && resp.StatusCode < 300
 			if success != test.wantSuccess {
 				t.Errorf("PUT to %q with ContentType %q got status code %d, wanted 2xx? %v", test.urlDescription, test.contentType, resp.StatusCode, test.wantSuccess)
-				gotBody, _ := ioutil.ReadAll(resp.Body)
+				gotBody, _ := io.ReadAll(resp.Body)
 				t.Errorf(string(gotBody))
 			}
 		}
@@ -2487,10 +2501,10 @@ func testSignedURL(t *testing.T, newHarness HarnessMaker) {
 			success := resp.StatusCode >= 200 && resp.StatusCode < 300
 			if success != test.wantSuccess {
 				t.Errorf("GET to %q got status code %d, want 2xx? %v", test.urlDescription, resp.StatusCode, test.wantSuccess)
-				gotBody, _ := ioutil.ReadAll(resp.Body)
+				gotBody, _ := io.ReadAll(resp.Body)
 				t.Errorf(string(gotBody))
 			} else if success {
-				gotBody, err := ioutil.ReadAll(resp.Body)
+				gotBody, err := io.ReadAll(resp.Body)
 				if err != nil {
 					t.Errorf("GET to %q failed to read response body: %v", test.urlDescription, err)
 				} else if gotBodyStr := string(gotBody); gotBodyStr != contents {
@@ -2519,7 +2533,7 @@ func testSignedURL(t *testing.T, newHarness HarnessMaker) {
 			defer resp.Body.Close()
 			success := resp.StatusCode >= 200 && resp.StatusCode < 300
 			if success != test.wantSuccess {
-				gotBody, _ := ioutil.ReadAll(resp.Body)
+				gotBody, _ := io.ReadAll(resp.Body)
 				t.Errorf(string(gotBody))
 				t.Fatalf("DELETE to %q got status code %d, want 2xx? %v", test.urlDescription, resp.StatusCode, test.wantSuccess)
 			}
@@ -2534,7 +2548,7 @@ func testSignedURL(t *testing.T, newHarness HarnessMaker) {
 			defer resp.Body.Close()
 			if resp.StatusCode != 404 {
 				t.Errorf("GET after DELETE got status code %d, want 404", resp.StatusCode)
-				gotBody, _ := ioutil.ReadAll(resp.Body)
+				gotBody, _ := io.ReadAll(resp.Body)
 				t.Errorf(string(gotBody))
 			}
 		}

blob/example_test.go

@@ -18,7 +18,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"os"
 
@@ -570,7 +569,7 @@ func ExampleAttributes_As() {
 }
 
 func newTempDir() (string, func()) {
-	dir, err := ioutil.TempDir("", "go-cloud-blob-example")
+	dir, err := os.MkdirTemp("", "go-cloud-blob-example")
 	if err != nil {
 		panic(err)
 	}

blob/fileblob/example_test.go

@@ -17,7 +17,6 @@ package fileblob_test
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"os"
 	"path/filepath"
@@ -46,7 +45,7 @@ func ExampleOpenBucket() {
 
 func Example_openBucketFromURL() {
 	// Create a temporary directory.
-	dir, err := ioutil.TempDir("", "go-cloud-fileblob-example")
+	dir, err := os.MkdirTemp("", "go-cloud-fileblob-example")
 	if err != nil {
 		log.Fatal(err)
 	}

blob/fileblob/fileblob.go

@@ -73,7 +73,6 @@ import (
 	"hash"
 	"io"
 	"io/fs"
-	"io/ioutil"
 	"net/url"
 	"os"
 	"path/filepath"
@@ -222,7 +221,7 @@ func (o *URLOpener) forParams(ctx context.Context, q url.Values) (*Options, erro
 		if err != nil {
 			return nil, err
 		}
-		sk, err := ioutil.ReadFile(keyPath)
+		sk, err := os.ReadFile(keyPath)
 		if err != nil {
 			return nil, err
 		}

blob/fileblob/fileblob_test.go

@@ -19,7 +19,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
@@ -215,22 +214,16 @@ func BenchmarkFileblob(b *testing.B) {
 // File-specific unit tests.
 func TestNewBucket(t *testing.T) {
 	t.Run("BucketDirMissing", func(t *testing.T) {
-		dir, err := ioutil.TempDir("", "fileblob")
-		if err != nil {
-			t.Fatal(err)
-		}
-		defer os.RemoveAll(dir)
+		dir := t.TempDir()
+
 		_, gotErr := OpenBucket(filepath.Join(dir, "notfound"), nil)
 		if gotErr == nil {
 			t.Errorf("got nil want error")
 		}
 	})
 	t.Run("BucketDirMissingWithCreateDir", func(t *testing.T) {
-		dir, err := ioutil.TempDir("", "fileblob")
-		if err != nil {
-			t.Fatal(err)
-		}
-		defer os.RemoveAll(dir)
+		dir := t.TempDir()
+
 		b, gotErr := OpenBucket(filepath.Join(dir, "notfound"), &Options{CreateDir: true})
 		if gotErr != nil {
 			t.Errorf("got error %v", gotErr)
@@ -244,11 +237,12 @@ func TestNewBucket(t *testing.T) {
 		}
 	})
 	t.Run("BucketIsFile", func(t *testing.T) {
-		f, err := ioutil.TempFile("", "fileblob")
+		dir := t.TempDir()
+
+		f, err := os.CreateTemp(dir, "fileblob")
 		if err != nil {
 			t.Fatal(err)
 		}
-		defer os.Remove(f.Name())
 		_, gotErr := OpenBucket(f.Name(), nil)
 		if gotErr == nil {
 			t.Errorf("got nil want error")
@@ -257,11 +251,8 @@ func TestNewBucket(t *testing.T) {
 }
 
 func TestSignedURLReturnsUnimplementedWithNoURLSigner(t *testing.T) {
-	dir, err := ioutil.TempDir("", "fileblob")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer os.RemoveAll(dir)
+	dir := t.TempDir()
+
 	b, err := OpenBucket(dir, nil)
 	if err != nil {
 		t.Fatal(err)
@@ -352,15 +343,15 @@ func TestOpenBucketFromURL(t *testing.T) {
 	if err := os.MkdirAll(filepath.Join(dir, subdir), os.ModePerm); err != nil {
 		t.Fatal(err)
 	}
-	if err := ioutil.WriteFile(filepath.Join(dir, "myfile.txt"), []byte("hello world"), 0666); err != nil {
+	if err := os.WriteFile(filepath.Join(dir, "myfile.txt"), []byte("hello world"), 0666); err != nil {
 		t.Fatal(err)
 	}
 	// To avoid making another temp dir, use the bucket directory to hold the secret key file.
 	secretKeyPath := filepath.Join(dir, "secret.key")
-	if err := ioutil.WriteFile(secretKeyPath, []byte("secret key"), 0666); err != nil {
+	if err := os.WriteFile(secretKeyPath, []byte("secret key"), 0666); err != nil {
 		t.Fatal(err)
 	}
-	if err := ioutil.WriteFile(filepath.Join(dir, subdir, "myfileinsubdir.txt"), []byte("hello world in subdir"), 0666); err != nil {
+	if err := os.WriteFile(filepath.Join(dir, subdir, "myfileinsubdir.txt"), []byte("hello world in subdir"), 0666); err != nil {
 		t.Fatal(err)
 	}
 	// Convert dir to a URL path, adding a leading "/" if needed on Windows.
@@ -460,10 +451,8 @@ func TestListAtRoot(t *testing.T) {
 	}
 	defer b.Close()
 
-	dir, err := ioutil.TempDir("", "fileblob")
-	if err != nil {
-		t.Fatalf("Got error creating temp dir: %#v", err)
-	}
+	dir := t.TempDir()
+
 	f, err := os.Create(filepath.Join(dir, "file.txt"))
 	if err != nil {
 		t.Fatalf("Got error creating file: %#v", err)
@@ -487,11 +476,8 @@ func TestListAtRoot(t *testing.T) {
 }
 
 func TestSkipMetadata(t *testing.T) {
-	dir, err := ioutil.TempDir("", "fileblob*")
-	if err != nil {
-		t.Fatalf("Got error creating temp dir: %#v", err)
-	}
-	defer os.RemoveAll(dir)
+	dir := t.TempDir()
+
 	dirpath := filepath.ToSlash(dir)
 	if os.PathSeparator != '/' && !strings.HasPrefix(dirpath, "/") {
 		dirpath = "/" + dirpath

blob/gcsblob/gcsblob.go

@@ -63,7 +63,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/url"
 	"os"
@@ -248,7 +247,7 @@ func (o *URLOpener) forParams(ctx context.Context, q url.Values) (*Options, *gcp
 		}
 	}
 	if keyPath := q.Get("private_key_path"); keyPath != "" {
-		pk, err := ioutil.ReadFile(keyPath)
+		pk, err := os.ReadFile(keyPath)
 		if err != nil {
 			return nil, nil, err
 		}
@@ -345,7 +344,7 @@ type bucket struct {
 	opts   *Options
 }
 
-var emptyBody = ioutil.NopCloser(strings.NewReader(""))
+var emptyBody = io.NopCloser(strings.NewReader(""))
 
 // reader reads a GCS object. It implements driver.Reader.
 type reader struct {