1 files changed, 106 insertions, 1 deletions
diff --git a/usage_test.go b/usage_test.go
index 1e2aca4..b2bcab1 100644
--- a/usage_test.go
+++ b/usage_test.go
@@ -260,6 +260,39 @@ Options:
 	assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
 }
 
+type userDefinedVersionFlag struct {
+	ShowVersion bool `arg:"--version" help:"this is a user-defined version flag"`
+}
+
+// Version returns the version for this program
+func (userDefinedVersionFlag) Version() string {
+	return "example 3.2.1"
+}
+
+func TestUsageWithUserDefinedVersionFlag(t *testing.T) {
+	expectedUsage := "example 3.2.1\nUsage: example [--version]"
+
+	expectedHelp := `
+example 3.2.1
+Usage: example [--version]
+
+Options:
+  --version              this is a user-defined version flag
+  --help, -h             display this help and exit
+`
+	os.Args[0] = "example"
+	p, err := NewParser(Config{}, &userDefinedVersionFlag{})
+	require.NoError(t, err)
+
+	var help bytes.Buffer
+	p.WriteHelp(&help)
+	assert.Equal(t, expectedHelp[1:], help.String())
+
+	var usage bytes.Buffer
+	p.WriteUsage(&usage)
+	assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
+}
+
 type described struct{}
 
 // Described returns the description for this program
@@ -415,6 +448,50 @@ Options:
 	assert.Equal(t, expectedUsage, usage.String())
 }
 
+func TestUsageWithSubcommands(t *testing.T) {
+	expectedUsage := "Usage: example child [--values VALUES]"
+
+	expectedHelp := `
+Usage: example child [--values VALUES]
+
+Options:
+  --values VALUES        Values
+
+Global options:
+  --verbose, -v          verbosity level
+  --help, -h             display this help and exit
+`
+
+	var args struct {
+		Verbose bool `arg:"-v" help:"verbosity level"`
+		Child   *struct {
+			Values []float64 `help:"Values"`
+		} `arg:"subcommand:child"`
+	}
+
+	os.Args[0] = "example"
+	p, err := NewParser(Config{}, &args)
+	require.NoError(t, err)
+
+	_ = p.Parse([]string{"child"})
+
+	var help bytes.Buffer
+	p.WriteHelp(&help)
+	assert.Equal(t, expectedHelp[1:], help.String())
+
+	var help2 bytes.Buffer
+	p.WriteHelpForSubcommand(&help2, "child")
+	assert.Equal(t, expectedHelp[1:], help2.String())
+
+	var usage bytes.Buffer
+	p.WriteUsage(&usage)
+	assert.Equal(t, expectedUsage, strings.TrimSpace(usage.String()))
+
+	var usage2 bytes.Buffer
+	p.WriteUsageForSubcommand(&usage2, "child")
+	assert.Equal(t, expectedUsage, strings.TrimSpace(usage2.String()))
+}
+
 func TestUsageWithNestedSubcommands(t *testing.T) {
 	expectedUsage := "Usage: example child nested [--enable] OUTPUT"
 
@@ -450,6 +527,8 @@ Global options:
 
 	_ = p.Parse([]string{"child", "nested", "value"})
 
+	assert.Equal(t, []string{"child", "nested"}, p.SubcommandNames())
+
 	var help bytes.Buffer
 	p.WriteHelp(&help)
 	assert.Equal(t, expectedHelp[1:], help.String())
@@ -471,7 +550,7 @@ func TestNonexistentSubcommand(t *testing.T) {
 	var args struct {
 		sub *struct{} `arg:"subcommand"`
 	}
-	p, err := NewParser(Config{}, &args)
+	p, err := NewParser(Config{Exit: func(int) {}}, &args)
 	require.NoError(t, err)
 
 	var b bytes.Buffer
@@ -716,3 +795,29 @@ Options:
 	p.WriteHelp(&help)
 	assert.Equal(t, expectedHelp[1:], help.String())
 }
+
+func TestHelpShowsSubcommandAliases(t *testing.T) {
+	expectedHelp := `
+Usage: example <command> [<args>]
+
+Options:
+  --help, -h             display this help and exit
+
+Commands:
+  remove, rm, r          remove something from somewhere
+  simple                 do something simple
+  halt, stop             stop now
+`
+
+	var args struct {
+		Remove *struct{} `arg:"subcommand:remove|rm|r" help:"remove something from somewhere"`
+		Simple *struct{} `arg:"subcommand" help:"do something simple"`
+		Stop   *struct{} `arg:"subcommand:halt|stop" help:"stop now"`
+	}
+	p, err := NewParser(Config{Program: "example"}, &args)
+	require.NoError(t, err)
+
+	var help bytes.Buffer
+	p.WriteHelp(&help)
+	assert.Equal(t, expectedHelp[1:], help.String())
+}