Add tests for help topics

pkg/cmd/root/help_topic.go

@@ -1,8 +1,6 @@
 package root
 
 import (
-	"fmt"
-
 	"github.com/MakeNowJust/heredoc"
 	"github.com/spf13/cobra"
 )
@@ -41,6 +39,7 @@ func NewHelpTopic(topic string) *cobra.Command {
 		Long:   topicContent[topic],
 		Hidden: true,
 		Args:   cobra.NoArgs,
+		Run:    helpTopicHelpFunc,
 	}
 
 	cmd.SetHelpFunc(helpTopicHelpFunc)
@@ -50,27 +49,10 @@ func NewHelpTopic(topic string) *cobra.Command {
 }
 
 func helpTopicHelpFunc(command *cobra.Command, args []string) {
-	if len(args) >= 2 && args[1] != "--help" && args[1] != "-h" {
-		command.Printf("unknown command %q for %q\n", args[1], command.CommandPath())
-
-		if args[1] == "help" {
-			command.Print("\nDid you mean this?\n")
-			command.Printf("\t%s\n\n", "--help")
-		} else {
-			command.Printf("\n")
-		}
-
-		helpTopicUsageFunc(command)
-		command.Printf("\n")
-		hasFailed = true
-		return
-	}
-
-	fmt.Fprint(command.OutOrStdout(), command.Long)
+	command.Print(command.Long)
 }
 
 func helpTopicUsageFunc(command *cobra.Command) error {
-	command.Printf("Usage:  gh help %s", command.Use)
-
+	command.Printf("Usage: gh help %s", command.Use)
 	return nil
 }

pkg/cmd/root/help_topic_test.go

@@ -0,0 +1,79 @@
+package root
+
+import (
+	"testing"
+
+	"github.com/cli/cli/pkg/iostreams"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNewHelpTopic(t *testing.T) {
+	tests := []struct {
+		name     string
+		topic    string
+		args     []string
+		flags    []string
+		wantsErr bool
+	}{
+		{
+			name:     "valid topic",
+			topic:    "environment",
+			args:     []string{},
+			flags:    []string{},
+			wantsErr: false,
+		},
+		{
+			name:     "invalid topic",
+			topic:    "invalid",
+			args:     []string{},
+			flags:    []string{},
+			wantsErr: false,
+		},
+		{
+			name:     "more than zero args",
+			topic:    "environment",
+			args:     []string{"invalid"},
+			flags:    []string{},
+			wantsErr: true,
+		},
+		{
+			name:     "more than zero flags",
+			topic:    "environment",
+			args:     []string{},
+			flags:    []string{"--invalid"},
+			wantsErr: true,
+		},
+		{
+			name:     "help arg",
+			topic:    "environment",
+			args:     []string{"help"},
+			flags:    []string{},
+			wantsErr: true,
+		},
+		{
+			name:     "help flag",
+			topic:    "environment",
+			args:     []string{},
+			flags:    []string{"--help"},
+			wantsErr: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, _, stdout, stderr := iostreams.Test()
+
+			cmd := NewHelpTopic(tt.topic)
+			cmd.SetArgs(append(tt.args, tt.flags...))
+			cmd.SetOut(stdout)
+			cmd.SetErr(stderr)
+
+			_, err := cmd.ExecuteC()
+			if tt.wantsErr {
+				assert.Error(t, err)
+				return
+			}
+			assert.NoError(t, err)
+		})
+	}
+}

pkg/cmd/root/root.go

@@ -90,7 +90,7 @@ func NewCmdRoot(f *cmdutil.Factory, version, buildDate string) *cobra.Command {
 	cmd.AddCommand(gistCmd.NewCmdGist(f))
 	cmd.AddCommand(NewCmdCompletion(f.IOStreams))
 
-	// Help Topics
+	// Help topics
 	cmd.AddCommand(NewHelpTopic("environment"))
 
 	// the `api` command should not inherit any extra HTTP headers