feat: list installed packages

README.md

@@ -82,6 +82,20 @@ $ ls -a .bash*
 .bash_logout
 ```
 
+You can also list the packages installed in a given directory. If you do not
+override it with the `--target` flag, then it lists packages installed into the
+current working directory by default.
+
+```console
+$ stowaway stow dotfiles/bash stowaway/examples/git
+$ stowaway packages
+/home/me/stowaway/examples/git
+/home/me/dotfiles/bash
+$ stowaway packages --prefix /home/me/stowaway
+/home/me/stowaway/examples/git
+$ stowaway stow --delete dotfiles/bash stowaway/examples/git
+```
+
 ### Interactive mode
 You can also pass the `--interactive` flag to the `stow` command, which will
 prompt the user to select which packages they want to install or uninstall from

cmd/packages.go

@@ -0,0 +1,70 @@
+package cmd
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/jamesbehr/stowaway/filesystem"
+	"github.com/spf13/cobra"
+)
+
+var prefix string
+
+var packagesCmd = &cobra.Command{
+	Use:   "packages",
+	Short: "List installed packages",
+	Run: func(cmd *cobra.Command, args []string) {
+		pwd, err := os.Getwd()
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		if target == "" {
+			target = pwd
+		} else {
+			target, err = filepath.Abs(target)
+			if err != nil {
+				log.Fatal(err)
+			}
+		}
+
+		targetPath := filesystem.MakePath(target)
+
+		state := targetPath.Join(".stowaway")
+
+		files, err := state.ReadDir()
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		if prefix != "" {
+			prefix, err = filepath.Abs(prefix)
+			if err != nil {
+				log.Fatal(err)
+			}
+		}
+
+		for _, file := range files {
+			if !file.IsDir() {
+				continue
+			}
+
+			source, err := state.Join(file.Name(), "source").Readlink()
+			if err != nil {
+				log.Fatal(err)
+			}
+
+			if prefix == "" || strings.HasPrefix(source.String(), prefix) {
+				fmt.Println(source)
+			}
+		}
+	},
+}
+
+func init() {
+	packagesCmd.Flags().StringVarP(&target, "target", "t", "", "directory to list installed packages for (default is $PWD)")
+	packagesCmd.Flags().StringVarP(&prefix, "prefix", "p", "", "only list packages that start with this")
+}

cmd/root.go

@@ -14,6 +14,7 @@ var rootCmd = &cobra.Command{
 
 func init() {
 	rootCmd.AddCommand(stowCmd)
+	rootCmd.AddCommand(packagesCmd)
 }
 
 func Execute() {

filesystem/path.go

@@ -82,6 +82,10 @@ func (p Path) Symlink(target Path) error {
 	return os.Symlink(string(target), string(p))
 }
 
+func (p Path) ReadDir() ([]fs.DirEntry, error) {
+	return os.ReadDir(string(p))
+}
+
 func (p Path) Walk(f filepath.WalkFunc) error {
 	fsys := os.DirFS(string(p))
 	return fs.WalkDir(fsys, ".", func(path string, entry fs.DirEntry, err error) error {