From 7fc5a00dbbda00f9d967f4059a9ffb3a9a7bea66 Mon Sep 17 00:00:00 2001
From: gammazero <11790789+gammazero@users.noreply.github.com>
Date: Wed, 2 Oct 2024 02:07:12 -0700
Subject: [PATCH] Stop using github.com/mitchellh/go-homedir

This repo is archived, no longer needed, and no longer maintained.
---
 assigner/config/config.go |  4 +--
 config/config.go          |  4 +--
 fsutil/fsutil.go          | 59 ++++++++++++++++++++++++++++-----------
 fsutil/fsutil_test.go     | 33 ++++++++++++++++++++++
 go.mod                    |  1 -
 go.sum                    |  2 --
 6 files changed, 80 insertions(+), 23 deletions(-)

diff --git a/assigner/config/config.go b/assigner/config/config.go
index 963438770..3a9bc12be 100644
--- a/assigner/config/config.go
+++ b/assigner/config/config.go
@@ -7,7 +7,7 @@ import (
 	"path/filepath"
 
 	sticfg "github.com/ipni/storetheindex/config"
-	"github.com/mitchellh/go-homedir"
+	"github.com/ipni/storetheindex/fsutil"
 )
 
 // Config is used to load config files.
@@ -65,7 +65,7 @@ func PathRoot() (string, error) {
 	if dir != "" {
 		return dir, nil
 	}
-	return homedir.Expand(DefaultPathRoot)
+	return fsutil.ExpandHome(DefaultPathRoot)
 }
 
 // Load reads the json-serialized config at the specified path.
diff --git a/config/config.go b/config/config.go
index 5c646f3ba..00a49c588 100644
--- a/config/config.go
+++ b/config/config.go
@@ -7,7 +7,7 @@ import (
 	"os"
 	"path/filepath"
 
-	"github.com/mitchellh/go-homedir"
+	"github.com/ipni/storetheindex/fsutil"
 )
 
 // Config is used to load config files.
@@ -74,7 +74,7 @@ func PathRoot() (string, error) {
 	if dir != "" {
 		return dir, nil
 	}
-	return homedir.Expand(DefaultPathRoot)
+	return fsutil.ExpandHome(DefaultPathRoot)
 }
 
 // Load reads the json-serialized config at the specified path.
diff --git a/fsutil/fsutil.go b/fsutil/fsutil.go
index bf7b1f106..c844a8230 100644
--- a/fsutil/fsutil.go
+++ b/fsutil/fsutil.go
@@ -3,10 +3,10 @@ package fsutil
 import (
 	"errors"
 	"fmt"
+	"io/fs"
 	"os"
+	"path/filepath"
 	"time"
-
-	"github.com/mitchellh/go-homedir"
 )
 
 // DirWritable checks if a directory is writable. If the directory does
@@ -17,37 +17,64 @@ func DirWritable(dir string) error {
 	}
 
 	var err error
-	dir, err = homedir.Expand(dir)
+	dir, err = ExpandHome(dir)
 	if err != nil {
 		return err
 	}
-
-	if _, err = os.Stat(dir); err != nil {
-		if errors.Is(err, os.ErrNotExist) {
-			// dir doesn't exist, check that we can create it
-			err = os.Mkdir(dir, 0o775)
+	fi, err := os.Stat(dir)
+	if err != nil {
+		if errors.Is(err, fs.ErrNotExist) {
+			// Directory does not exist, so create it.
+			err = os.Mkdir(dir, 0775)
 			if err == nil {
 				return nil
 			}
 		}
-		if errors.Is(err, os.ErrPermission) {
-			err = os.ErrPermission
+		if errors.Is(err, fs.ErrPermission) {
+			err = fs.ErrPermission
 		}
-		return fmt.Errorf("cannot write to %s: %w", dir, err)
+		return fmt.Errorf("directory not writable: %s: %w", dir, err)
+	}
+	if !fi.IsDir() {
+		return fmt.Errorf("not a directory: %s", dir)
 	}
 
-	// dir exists, make sure we can write to it
-	file, err := os.CreateTemp(dir, "test")
+	// Directory exists, check that a file can be written.
+	file, err := os.CreateTemp(dir, "writetest")
 	if err != nil {
-		if errors.Is(err, os.ErrPermission) {
-			err = os.ErrPermission
+		if errors.Is(err, fs.ErrPermission) {
+			err = fs.ErrPermission
 		}
-		return fmt.Errorf("cannot write to %s: %w", dir, err)
+		return fmt.Errorf("directory not writable: %s: %w", dir, err)
 	}
 	file.Close()
 	return os.Remove(file.Name())
 }
 
+// ExpandHome expands the path to include the home directory if the path is
+// prefixed with `~`. If it isn't prefixed with `~`, the path is returned
+// as-is.
+func ExpandHome(path string) (string, error) {
+	if path == "" {
+		return path, nil
+	}
+
+	if path[0] != '~' {
+		return path, nil
+	}
+
+	if len(path) > 1 && path[1] != '/' && path[1] != '\\' {
+		return "", errors.New("cannot expand user-specific home dir")
+	}
+
+	dir, err := os.UserHomeDir()
+	if err != nil {
+		return "", err
+	}
+
+	return filepath.Join(dir, path[1:]), nil
+}
+
 // FileChanged returns the modification time of a file and true if different
 // from the given time.
 func FileChanged(filePath string, modTime time.Time) (time.Time, bool, error) {
diff --git a/fsutil/fsutil_test.go b/fsutil/fsutil_test.go
index fcf4fddcb..b67844692 100644
--- a/fsutil/fsutil_test.go
+++ b/fsutil/fsutil_test.go
@@ -80,3 +80,36 @@ func TestFileExists(t *testing.T) {
 
 	require.True(t, fsutil.FileExists(fileName))
 }
+
+func TestExpandHome(t *testing.T) {
+	dir, err := fsutil.ExpandHome("")
+	require.NoError(t, err)
+	require.Equal(t, "", dir)
+
+	origDir := filepath.Join("somedir", "somesub")
+	dir, err = fsutil.ExpandHome(origDir)
+	require.NoError(t, err)
+	require.Equal(t, origDir, dir)
+
+	_, err = fsutil.ExpandHome(filepath.FromSlash("~nosuchuser/somedir"))
+	require.Error(t, err)
+
+	homeEnv := "HOME"
+	if runtime.GOOS == "windows" {
+		homeEnv = "USERPROFILE"
+	}
+	origHome := os.Getenv(homeEnv)
+	defer os.Setenv(homeEnv, origHome)
+	homeDir := filepath.Join(t.TempDir(), "testhome")
+	os.Setenv(homeEnv, homeDir)
+
+	const subDir = "mytmp"
+	origDir = filepath.Join("~", subDir)
+	dir, err = fsutil.ExpandHome(origDir)
+	require.NoError(t, err)
+	require.Equal(t, filepath.Join(homeDir, subDir), dir)
+
+	os.Unsetenv(homeEnv)
+	_, err = fsutil.ExpandHome(origDir)
+	require.Error(t, err)
+}
diff --git a/go.mod b/go.mod
index f1fc13a91..30cfd9949 100644
--- a/go.mod
+++ b/go.mod
@@ -28,7 +28,6 @@ require (
 	github.com/ipni/go-libipni v0.5.25
 	github.com/libp2p/go-libp2p v0.36.3
 	github.com/libp2p/go-msgio v0.3.0
-	github.com/mitchellh/go-homedir v1.1.0
 	github.com/multiformats/go-multiaddr v0.13.0
 	github.com/multiformats/go-multicodec v0.9.0
 	github.com/multiformats/go-multihash v0.2.3
diff --git a/go.sum b/go.sum
index 7daf78213..ab1440217 100644
--- a/go.sum
+++ b/go.sum
@@ -581,8 +581,6 @@ github.com/minio/sha256-simd v0.1.1-0.20190913151208-6de447530771/go.mod h1:B5e1
 github.com/minio/sha256-simd v0.1.1/go.mod h1:B5e1o+1/KgNmWrSQK08Y6Z1Vb5pwIktudl0J58iy0KM=
 github.com/minio/sha256-simd v1.0.1 h1:6kaan5IFmwTNynnKKpDHe6FWHohJOHhCPchzK49dzMM=
 github.com/minio/sha256-simd v1.0.1/go.mod h1:Pz6AKMiUdngCLpeTL/RJY1M9rUuPMYujV5xJjtbRSN8=
-github.com/mitchellh/go-homedir v1.1.0 h1:lukF9ziXFxDFPkA1vsr5zpc1XuPDn/wFntq5mG+4E0Y=
-github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/moby/docker-image-spec v1.3.1 h1:jMKff3w6PgbfSa69GfNg+zN/XLhfXJGnEx3Nl2EsFP0=
 github.com/moby/docker-image-spec v1.3.1/go.mod h1:eKmb5VW8vQEh/BAr2yvVNvuiJuY6UIocYsFu/DxxRpo=
 github.com/moby/term v0.0.0-20210619224110-3f7ff695adc6 h1:dcztxKSvZ4Id8iPpHERQBbIJfabdt4wUm5qy3wOL2Zc=