Fix failing test

There was some breaking changes described at
https://github.com/mvdan/sh/issues/335#issuecomment-447605295

internal/execext/exec.go

@@ -9,6 +9,7 @@ import (
 
 	"mvdan.cc/sh/expand"
 	"mvdan.cc/sh/interp"
+	"mvdan.cc/sh/shell"
 	"mvdan.cc/sh/syntax"
 )
 
@@ -67,3 +68,16 @@ func IsExitError(err error) bool {
 		return false
 	}
 }
+
+// Expand is a helper to mvdan.cc/shell.Fields that returns the first field
+// if available.
+func Expand(s string) (string, error) {
+	fields, err := shell.Fields(s, nil)
+	if err != nil {
+		return "", err
+	}
+	if len(fields) > 0 {
+		return fields[0], nil
+	}
+	return "", nil
+}

internal/status/glob.go

@@ -4,8 +4,9 @@ import (
 	"path/filepath"
 	"sort"
 
+	"github.com/go-task/task/v2/internal/execext"
+
 	"github.com/mattn/go-zglob"
-	"mvdan.cc/sh/shell"
 )
 
 func glob(dir string, globs []string) (files []string, err error) {
@@ -13,7 +14,7 @@ func glob(dir string, globs []string) (files []string, err error) {
 		if !filepath.IsAbs(g) {
 			g = filepath.Join(dir, g)
 		}
-		g, err = shell.Expand(g, nil)
+		g, err = execext.Expand(g)
 		if err != nil {
 			return nil, err
 		}

variables.go

@@ -3,10 +3,9 @@ package task
 import (
 	"path/filepath"
 
+	"github.com/go-task/task/v2/internal/execext"
 	"github.com/go-task/task/v2/internal/taskfile"
 	"github.com/go-task/task/v2/internal/templater"
-
-	"mvdan.cc/sh/shell"
 )
 
 // CompiledTask returns a copy of a task, but replacing variables in almost all
@@ -37,7 +36,7 @@ func (e *Executor) CompiledTask(call taskfile.Call) (*taskfile.Task, error) {
 		Prefix:      r.Replace(origTask.Prefix),
 		IgnoreError: origTask.IgnoreError,
 	}
-	new.Dir, err = shell.Expand(new.Dir, nil)
+	new.Dir, err = execext.Expand(new.Dir)
 	if err != nil {
 		return nil, err
 	}