pkg/tool/file: add Mkdir, MkdirAll

Closes #420

Change-Id: Iff8d66e9151f3a76f8c3986cab0eb26a9ff33126
Signed-off-by: Jean-Philippe Braun <eon@patapon.info>
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/530736
Reviewed-by: Paul Jolly <paul@myitcv.io>

Author: eonpatapon

pkg/tool/file/doc.go

@@ -75,3 +75,27 @@ Glob: {
 	glob: !=""
 	files: [...string]
 }
+
+// Mkdir creates a directory at the specified path.
+Mkdir: {
+	$id: "tool/file.Mkdir"
+
+	// The directory path to create.
+	// If path is already a directory, Mkdir does nothing.
+	// If path already exists and is not a directory, Mkdir will return an error.
+	path: string
+
+	// When true any necessary parents are created as well.
+	createParents: bool | *false
+
+	// Directory mode and permission bits.
+	permissions: int | *0o755
+}
+
+// MkdirAll creates a directory at the specified path along with any necessary
+// parents.
+// If path is already a directory, MkdirAll does nothing.
+// If path already exists and is not a directory, MkdirAll will return an error.
+MkdirAll: Mkdir & {
+	createParents: true
+}

pkg/tool/file/file.cue

@@ -23,6 +23,7 @@ import (
 	"path/filepath"
 
 	"cuelang.org/go/cue"
+	"cuelang.org/go/cue/errors"
 	"cuelang.org/go/internal/task"
 )
 
@@ -31,17 +32,20 @@ func init() {
 	task.Register("tool/file.Append", newAppendCmd)
 	task.Register("tool/file.Create", newCreateCmd)
 	task.Register("tool/file.Glob", newGlobCmd)
+	task.Register("tool/file.Mkdir", newMkdirCmd)
 }
 
 func newReadCmd(v cue.Value) (task.Runner, error)   { return &cmdRead{}, nil }
 func newAppendCmd(v cue.Value) (task.Runner, error) { return &cmdAppend{}, nil }
 func newCreateCmd(v cue.Value) (task.Runner, error) { return &cmdCreate{}, nil }
 func newGlobCmd(v cue.Value) (task.Runner, error)   { return &cmdGlob{}, nil }
+func newMkdirCmd(v cue.Value) (task.Runner, error)  { return &cmdMkdir{}, nil }
 
 type cmdRead struct{}
 type cmdAppend struct{}
 type cmdCreate struct{}
 type cmdGlob struct{}
+type cmdMkdir struct{}
 
 func (c *cmdRead) Run(ctx *task.Context) (res interface{}, err error) {
 	filename := ctx.String("filename")
@@ -111,3 +115,29 @@ func (c *cmdGlob) Run(ctx *task.Context) (res interface{}, err error) {
 	files := map[string]interface{}{"files": m}
 	return files, err
 }
+
+func (c *cmdMkdir) Run(ctx *task.Context) (res interface{}, err error) {
+	path := ctx.String("path")
+	mode := ctx.Int64("permissions")
+	createParents, _ := ctx.Lookup("createParents").Bool()
+
+	if ctx.Err != nil {
+		return nil, ctx.Err
+	}
+
+	if createParents {
+		if err := os.MkdirAll(path, os.FileMode(mode)); err != nil {
+			return nil, errors.Wrapf(err, ctx.Obj.Pos(), "failed to create directory")
+		}
+	} else {
+		dir, err := os.Stat(path)
+		if err == nil && dir.IsDir() {
+			return nil, nil
+		}
+		if err := os.Mkdir(path, os.FileMode(mode)); err != nil {
+			return nil, errors.Wrapf(err, ctx.Obj.Pos(), "failed to create directory")
+		}
+	}
+
+	return nil, nil
+}

pkg/tool/file/file.go

@@ -137,3 +137,68 @@ func TestGlob(t *testing.T) {
 		t.Errorf("got %v; want %v", got, want)
 	}
 }
+
+func TestMkdir(t *testing.T) {
+	baseDir, err := os.MkdirTemp("", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(baseDir)
+
+	// simple dir creation
+	d1 := filepath.Join(baseDir, "foo")
+	v := parse(t, "tool/file.Mkdir", fmt.Sprintf(`{path: "%s"}`, d1))
+	_, err = (*cmdMkdir).Run(nil, &task.Context{Obj: v})
+	if err != nil {
+		t.Fatal(err)
+	}
+	fi1, err := os.Stat(d1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !fi1.IsDir() {
+		t.Fatal("not a directory")
+	}
+	expectedMode1 := os.ModeDir | 0755
+	if int(fi1.Mode()) != int(expectedMode1) {
+		t.Fatal("wrong permissions", fi1.Mode())
+	}
+
+	// dir already exists
+	v = parse(t, "tool/file.Mkdir", fmt.Sprintf(`{path: "%s"}`, d1))
+	_, err = (*cmdMkdir).Run(nil, &task.Context{Obj: v})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// create parents
+	// set permissions
+	d2 := filepath.Join(baseDir, "bar/x")
+	v = parse(t, "tool/file.MkdirAll", fmt.Sprintf(`{path: "%s", permissions: 0o700}`, d2))
+	_, err = (*cmdMkdir).Run(nil, &task.Context{Obj: v})
+	if err != nil {
+		t.Fatal(err)
+	}
+	fi2, err := os.Stat(d2)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !fi2.IsDir() {
+		t.Fatal("not a directory")
+	}
+	expectedMode2 := os.ModeDir | 0700
+	if int(fi2.Mode()) != int(expectedMode2) {
+		t.Fatal("wrong permissions", fi2.Mode())
+	}
+
+	// file at same path
+	f, err := ioutil.TempFile(baseDir, "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	v = parse(t, "tool/file.Mkdir", fmt.Sprintf(`{path: "%s"}`, f.Name()))
+	_, err = (*cmdMkdir).Run(nil, &task.Context{Obj: v})
+	if err == nil {
+		t.Fatal("should not create directory at existing filepath")
+	}
+}