Add support for passwordstore

For now, this only takes the first line of output from `pass`, which
should be the same behavior as `pass -c`.

cmd/config.go

@@ -35,6 +35,7 @@ type Config struct {
 	Bitwarden        bitwardenCommandConfig
 	LastPass         LastPassCommandConfig
 	Vault            vaultCommandConfig
+	Pass             PassCommandConfig
 	Data             map[string]interface{}
 	funcs            template.FuncMap
 	add              addCommandConfig

cmd/pass.go

@@ -0,0 +1,52 @@
+package cmd
+
+import (
+	"fmt"
+	"os/exec"
+	"strings"
+
+	"github.com/spf13/cobra"
+	"github.com/twpayne/chezmoi/lib/chezmoi"
+	vfs "github.com/twpayne/go-vfs"
+)
+
+var passCommand = &cobra.Command{
+	Use:   "pass",
+	Short: "Execute the pass CLI",
+	RunE:  makeRunE(config.runPassCommand),
+}
+
+// A PassCommandConfig is a configuration for the pass command.
+type PassCommandConfig struct {
+	Pass string
+}
+
+var passCache = make(map[string]string)
+
+func init() {
+	rootCommand.AddCommand(passCommand)
+	config.Pass.Pass = "pass"
+	config.addFunc("pass", config.passFunc)
+}
+
+func (c *Config) runPassCommand(fs vfs.FS, args []string) error {
+	return c.exec(append([]string{c.Pass.Pass}, args...))
+}
+
+func (c *Config) passFunc(id string) string {
+	if s, ok := passCache[id]; ok {
+		return s
+	}
+	name := c.Pass.Pass
+	args := []string{id}
+	if c.Verbose {
+		fmt.Printf("%s %s\n", name, strings.Join(args, " "))
+	}
+	output, err := exec.Command(name, args...).Output()
+	if err != nil {
+		chezmoi.ReturnTemplateFuncError(fmt.Errorf("pass: %s %s: %v", name, strings.Join(args, " "), err))
+	}
+	password := strings.Split(string(output), "\n")[0]
+	passCache[id] = password
+	return passCache[id]
+}