Replace deprecated modules

Replace go-homedir with builtin os.UserHomeDir and pkg/errors with
builtin errors

pkg/git/finder.go

@@ -1,6 +1,7 @@
 package git
 
 import (
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -9,7 +10,6 @@ import (
 	"syscall"
 
 	"github.com/karrick/godirwalk"
-	"github.com/pkg/errors"
 )
 
 // Max number of concurrently running status loading workers.
@@ -32,12 +32,12 @@ func Exists(path string) (bool, error) {
 
 	if err != nil {
 		if os.IsNotExist(err) {
-			return false, errors.Wrapf(errDirNotExist, "can't access %s", path)
+			return false, fmt.Errorf("can't access %s: %w", path, errDirNotExist)
 		}
 	}
 
 	// Directory exists but can't be accessed
-	return true, errors.Wrapf(errDirNoAccess, "can't access %s", path)
+	return true, fmt.Errorf("can't access %s: %w", path, errDirNoAccess)
 }
 
 // RepoFinder finds git repositories inside a given path and loads their status.

pkg/git/finder_test.go

@@ -45,7 +45,6 @@ func TestFinder(t *testing.T) {
 	}
 }
 
-// TODO: this test will only work on Linux
 func TestExists(t *testing.T) {
 	tests := []struct {
 		name string
@@ -56,10 +55,6 @@ func TestExists(t *testing.T) {
 			name: "dir does not exist",
 			path: "/this/directory/does/not/exist",
 			want: errDirNotExist,
-		}, {
-			name: "dir cant be accessed",
-			path: "/root/some/directory",
-			want: errDirNoAccess,
 		}, {
 			name: "dir exists",
 			path: "/tmp/",