Chdir

CHANGELOG.md

@@ -15,6 +15,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added `gi:load-system` function.
 - Added support for shebang at the start of a file.
 - Added support for ASDF style system component definitions.
+- Added `gi:getcwd` function.
+- Added `gi:chdir` function.
 
 ### Fixed
 - The CompileList function now correctly handles package prefixes.

package.go

@@ -856,6 +856,7 @@ func (obj *Package) Describe(b []byte, indent, right int, ansi bool) []byte {
 				b = append(b, indentSpaces[:mx-len(k)+1]...)
 			}
 		}
+		b = append(b, '\n')
 	}
 	if 0 < len(obj.classes) {
 		names = names[:0]

pkg/cl/trace.go

@@ -24,7 +24,7 @@ func init() {
 				},
 			},
 			Return: "list",
-			Text: `__trace__ turns tracing on for the listed function _name*. If the only name is _t_ then
+			Text: `__trace__ turns tracing on for the listed function _name_. If the only name is _t_ then
 tracing is turned on for all functions. If no functions are named then a list of the functions being
 traced is returned.`,
 			Examples: []string{

pkg/cl/typecase.go

@@ -80,8 +80,8 @@ func (f *Typecase) Call(s *slip.Scope, args slip.List, depth int) (result slip.O
 }
 
 func typecaseMatch(sym slip.Symbol, key slip.Object) bool {
-	if strings.EqualFold("null", string(sym)) && key == nil {
-		return true
+	if key == nil {
+		return strings.EqualFold("null", string(sym))
 	}
 	for _, h := range key.Hierarchy() {
 		if strings.EqualFold(string(h), string(sym)) {

pkg/gi/chdir.go

@@ -0,0 +1,48 @@
+// Copyright (c) 2026, Peter Ohler, All rights reserved.
+
+package gi
+
+import (
+	"os"
+
+	"github.com/ohler55/slip"
+)
+
+func defChdir() {
+	slip.Define(
+		func(args slip.List) slip.Object {
+			f := Chdir{Function: slip.Function{Name: "chdir", Args: args}}
+			f.Self = &f
+			return &f
+		},
+		&slip.FuncDoc{
+			Name: "chdir",
+			Args: []*slip.DocArg{
+				{
+					Name: "path",
+					Type: "string",
+					Text: "The directory to change to.",
+				},
+			},
+			Return: "nil",
+			Text:   `__chdir__ changes the current directory to _path_.`,
+		}, &Pkg)
+}
+
+// Chdir represents the chdir function.
+type Chdir struct {
+	slip.Function
+}
+
+// Call the function with the arguments provided.
+func (f *Chdir) Call(s *slip.Scope, args slip.List, depth int) slip.Object {
+	slip.CheckArgCount(s, depth, f, args, 1, 1)
+	vs, ok := args[0].(slip.String)
+	if !ok {
+		slip.TypePanic(s, depth, "path", args[0], "string")
+	}
+	if err := os.Chdir(string(vs)); err != nil {
+		panic(err)
+	}
+	return nil
+}

pkg/gi/getcwd.go

@@ -0,0 +1,37 @@
+// Copyright (c) 2026, Peter Ohler, All rights reserved.
+
+package gi
+
+import (
+	"os"
+
+	"github.com/ohler55/slip"
+)
+
+func defGetcwd() {
+	slip.Define(
+		func(args slip.List) slip.Object {
+			f := Getcwd{Function: slip.Function{Name: "getcwd", Args: args}}
+			f.Self = &f
+			return &f
+		},
+		&slip.FuncDoc{
+			Name:   "getcwd",
+			Args:   []*slip.DocArg{},
+			Return: "string",
+			Text:   `__getcwd__ return the current directory.`,
+		}, &Pkg)
+}
+
+// Getcwd represents the getcwd function.
+type Getcwd struct {
+	slip.Function
+}
+
+// Call the function with the arguments provided.
+func (f *Getcwd) Call(s *slip.Scope, args slip.List, depth int) slip.Object {
+	slip.CheckArgCount(s, depth, f, args, 0, 0)
+	dir, _ := os.Getwd()
+
+	return slip.String(dir)
+}

pkg/gi/pkg.go

@@ -284,6 +284,8 @@ func init() {
 		vv := Pkg.GetVarVal(f.Name())
 		vv.Const = true
 	}
+	defChdir()
+	defGetcwd()
 	defProcess()
 	defFindProcess()
 	defCommand()

test/gi/chdir_test.go

@@ -0,0 +1,35 @@
+// Copyright (c) 2026, Peter Ohler, All rights reserved.
+
+package gi_test
+
+import (
+	"os"
+	"testing"
+
+	"github.com/ohler55/slip"
+	"github.com/ohler55/slip/sliptest"
+)
+
+func TestChdirOk(t *testing.T) {
+	dir, _ := os.Getwd()
+	defer func() { _ = os.Chdir(dir) }()
+
+	(&sliptest.Function{
+		Source: `(progn (chdir "..") (getcwd))`,
+		Expect: `/slip\/test"$/`,
+	}).Test(t)
+}
+
+func TestChdirBadPath(t *testing.T) {
+	(&sliptest.Function{
+		Source:    `(chdir t)`,
+		PanicType: slip.TypeErrorSymbol,
+	}).Test(t)
+}
+
+func TestChdirError(t *testing.T) {
+	(&sliptest.Function{
+		Source:    `(chdir "....")`,
+		PanicType: slip.ErrorSymbol,
+	}).Test(t)
+}

test/gi/getcwd_test.go

@@ -0,0 +1,16 @@
+// Copyright (c) 2026, Peter Ohler, All rights reserved.
+
+package gi_test
+
+import (
+	"testing"
+
+	"github.com/ohler55/slip/sliptest"
+)
+
+func TestGetcwd(t *testing.T) {
+	(&sliptest.Function{
+		Source: `(getcwd)`,
+		Expect: `/slip\/test\/gi"$/`,
+	}).Test(t)
+}