Replace deprecated os.Is{Not,}Exist calls

This commit replaces deprecated calls to `os.Is{Not,}Exist` with the
newer `errors.Is(err, fs.Err{Not,}Exist)`.

internal/cli/params.go

@@ -2,6 +2,8 @@ package cli
 
 import (
 	"context"
+	"errors"
+	"io/fs"
 	"os"
 	"os/signal"
 	"path/filepath"
@@ -19,9 +21,9 @@ type Params struct {
 // Uses [ReadBaseDirectory] or falls back to [BaseDirectoryDefault].
 func ParamsFromEnv() (params Params, err error) {
 	// try to read the base directory!
-	value, err := ReadBaseDirectory() // TODO: Are we sure about the native environment here?
+	value, err := ReadBaseDirectory()
 	switch {
-	case os.IsNotExist(err):
+	case errors.Is(err, fs.ErrNotExist):
 		params.ConfigPath = bootstrap.BaseDirectoryDefault
 	case err == nil:
 		params.ConfigPath = value

internal/dis/component/exporter/exporter.go

@@ -2,8 +2,9 @@ package exporter
 
 import (
 	"crypto/rand"
+	"errors"
 	"fmt"
-	"os"
+	"io/fs"
 	"path/filepath"
 	"time"
 
@@ -72,7 +73,7 @@ func (*Exporter) newSnapshotName(prefix string) string {
 // NewStagingDir returns the path to a new snapshot directory.
 // The directory is guaranteed to have been freshly created.
 func (dis *Exporter) NewStagingDir(prefix string) (path string, err error) {
-	for path == "" || os.IsExist(err) {
+	for path == "" || errors.Is(err, fs.ErrExist) {
 		path = filepath.Join(dis.StagingPath(), dis.newSnapshotName(prefix))
 		err = fsx.Mkdir(path, fsx.DefaultFilePerm)
 	}

internal/dis/component/exporter/iface.go

@@ -2,7 +2,9 @@ package exporter
 
 import (
 	"context"
+	"errors"
 	"io"
+	"io/fs"
 	"os"
 	"path/filepath"
 
@@ -75,7 +77,7 @@ func (exporter *Exporter) MakeExport(ctx context.Context, progress io.Writer, ta
 	// create the staging directory
 	logging.LogMessage(progress, ctx, "Creating staging directory")
 	err = fsx.Mkdir(stagingDir, fsx.DefaultDirPerm)
-	if !os.IsExist(err) && err != nil {
+	if !errors.Is(err, fs.ErrExist) && err != nil {
 		return err
 	}
 

internal/dis/component/exporter/logger/logger.go

@@ -2,6 +2,8 @@ package logger
 
 import (
 	"context"
+	"errors"
+	"io/fs"
 	"os"
 
 	"github.com/FAU-CDI/wisski-distillery/internal/dis/component"
@@ -63,7 +65,7 @@ func (log *Logger) Log(ctx context.Context) ([]models.Export, error) {
 	// partition out the exports that have been deleted!
 	parts := collection.Partition(exports, func(s models.Export) bool {
 		_, err := os.Stat(s.Path)
-		return !os.IsNotExist(err)
+		return !errors.Is(err, fs.ErrNotExist)
 	})
 
 	// go and delete them!

internal/dis/component/ssh2/server_hostkeys.go

@@ -8,6 +8,7 @@ import (
 	"crypto/x509"
 	"encoding/pem"
 	"io"
+	"io/fs"
 	"os"
 
 	"github.com/FAU-CDI/wisski-distillery/pkg/fsx"
@@ -65,7 +66,7 @@ func (ssh2 *SSH2) UseOrMakeHostKey(progress io.Writer, ctx context.Context, serv
 func (ssh2 *SSH2) ReadOrMakeHostKey(progress io.Writer, ctx context.Context, privateKeyPath string, algorithm HostKeyAlgorithm) (key gossh.Signer, err error) {
 	hostKey := NewHostKey(algorithm)
 
-	if _, e := os.Lstat(privateKeyPath); os.IsNotExist(e) { // path doesn't exist => generate a new key there!
+	if _, e := os.Lstat(privateKeyPath); errors.Is(e, fs.ErrNotExist) { // path doesn't exist => generate a new key there!
 		err = ssh2.makeHostKey(progress, ctx, hostKey, privateKeyPath)
 		if err != nil {
 			err = errors.Wrap(err, "Unable to generate new host key")

pkg/fsx/copy.go

@@ -141,7 +141,7 @@ func CopyDirectory(ctx context.Context, dst, src string, onCopy func(dst, src st
 		// create the directory, but ignore an error if the directory already exists.
 		// this is so that we can copy one tree into another tree.
 		err = Mkdir(dst, info.Mode())
-		if os.IsExist(err) && IsDirectory(dst) {
+		if errors.Is(err, fs.ErrExist) && IsDirectory(dst) {
 			err = nil
 		}
 

pkg/fsx/create.go

@@ -1,6 +1,7 @@
 package fsx
 
 import (
+	"errors"
 	"io/fs"
 	"os"
 	"time"
@@ -40,7 +41,7 @@ func Touch(path string, perm fs.FileMode) error {
 	}
 	_, err := os.Stat(path)
 	switch {
-	case os.IsNotExist(err):
+	case errors.Is(err, fs.ErrNotExist):
 		f, err := Create(path, perm)
 		if err != nil {
 			return err

pkg/fsx/same.go

@@ -1,6 +1,8 @@
 package fsx
 
 import (
+	"errors"
+	"io/fs"
 	"os"
 	"path/filepath"
 )
@@ -60,7 +62,7 @@ func couldBeSameFile(path1, path2 string) (same, authorative bool) {
 		}
 
 		// only 1 file does not exist => they could be different
-		if os.IsNotExist(err1) != os.IsNotExist(err2) {
+		if errors.Is(err1, fs.ErrNotExist) != errors.Is(err2, fs.ErrNotExist) {
 			return
 		}
 	}

pkg/unpack/resource.go

@@ -83,7 +83,7 @@ func installDir(dst string, srcInfo fs.FileInfo, srcFile fs.ReadDirFile, src str
 	// create the destination
 	dstStat, dstErr := os.Stat(dst)
 	switch {
-	case os.IsNotExist(dstErr):
+	case errors.Is(dstErr, fs.ErrNotExist):
 		if err := fsx.MkdirAll(dst, srcInfo.Mode()); err != nil {
 			return errors.Wrapf(err, "Error creating destination directory %s", dst)
 		}