Merge pull request #98 from hashicorp/b-command-escaping

Fix panic displaying invoked command

.changelog/98.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+Fix rare panic that could occur on authentication error when running a command that had quoted arguments.
+```

internal/pkg/cmd/command_internal.go

@@ -11,6 +11,7 @@ import (
 	"net/http"
 	"os"
 	"slices"
+	"strconv"
 	"strings"
 
 	"github.com/go-openapi/runtime"
@@ -107,17 +108,7 @@ func (c *Command) Run(args []string) int {
 			return 1
 		} else if errors.As(err, &runtimeErr) && runtimeErr.IsCode(http.StatusUnauthorized) {
 			// Request failed because of authentication issues.
-			fmt.Fprintf(io.Err(), "%s %s\n\n",
-				cs.ErrorLabel(),
-				heredoc.New(io, heredoc.WithPreserveNewlines()).Mustf(`
-				Unauthorized request. Re-attempt by first logging out and back in, and then re-run the command.
-
-				  {{ Bold "$ hcp auth logout" }}
-				  {{ Bold "$ hcp auth login" }}
-				  {{ Bold "$ %s %s" }}
-			`, c.commandPath(), strings.Join(args, " "),
-				),
-			)
+			fmt.Fprintf(io.Err(), "%s %s\n\n", cs.ErrorLabel(), authErrorHelp(io, c.commandPath(), args))
 			return 1
 		}
 
@@ -128,6 +119,33 @@ func (c *Command) Run(args []string) int {
 	return 0
 }
 
+// authErrorHelp returns a help message for recovering from authentication errors.
+func authErrorHelp(io iostreams.IOStreams, commandPath string, args []string) string {
+	// Build the original command
+	command := "$ " + commandPath
+	for _, a := range args {
+		// If there are spaces in the argument, quote it.
+		if strings.Contains(a, " ") {
+			command += fmt.Sprintf(" %s", strconv.Quote(a))
+		} else {
+			command += fmt.Sprintf(" %s", a)
+		}
+	}
+
+	// Quote the entire command so we can inject it into the template as a
+	// variable.
+	command = strconv.Quote(command)
+
+	// Render the help message to logout, login, and re-run the command.
+	return heredoc.New(io, heredoc.WithPreserveNewlines(), heredoc.WithWidth(0)).Mustf(`
+		Unauthorized request. Re-attempt by first logging out and back in, and then re-run the command.
+
+		  {{ Bold "$ hcp auth logout" }}
+		  {{ Bold "$ hcp auth login" }}
+		  {{ with $cmd := %s }}{{ Bold $cmd }}{{ end }}
+	`, command)
+}
+
 // helpEntry is used to structure help output with titles.
 type helpEntry struct {
 	Title string

internal/pkg/cmd/command_internal_test.go

@@ -0,0 +1,24 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package cmd
+
+import (
+	"testing"
+
+	"github.com/hashicorp/hcp/internal/pkg/iostreams"
+	"github.com/stretchr/testify/require"
+)
+
+func TestAuthErrorHelp(t *testing.T) {
+	t.Parallel()
+	r := require.New(t)
+	io := iostreams.Test()
+
+	commandPath := "hcp example"
+	args := []string{"simple", "'single-quote'", `escaped \"inner\"`}
+
+	// Get the help text
+	helpText := authErrorHelp(io, commandPath, args)
+	r.Contains(helpText, `$ hcp example simple 'single-quote' "escaped \\\"inner\\\""`)
+}