Merge pull request #1 from jhughes1153/help_on_subcommands

Help on subcommands

argparse.go

@@ -11,6 +11,9 @@ import (
 // DisableDescription can be assigned as a command or arguments description to hide it from the Usage output
 const DisableDescription = "DISABLEDDESCRIPTIONWILLNOTSHOWUP"
 
+//disable help can be invoked from the parse and then needs to be propogated to subcommands
+var disableHelp = false
+
 // Command is a basic type for this package. It represents top level Parser as well as any commands and sub-commands
 // Command MUST NOT ever be created manually. Instead one should call NewCommand method of Parser or Command,
 // which will setup appropriate fields and call methods that have to be called when creating new command.
@@ -130,7 +133,11 @@ func (o *Command) NewCommand(name string, description string) *Command {
 	c.description = description
 	c.parsed = false
 	c.parent = o
-	c.exitOnHelp = o.exitOnHelp
+	if !disableHelp {
+		c.help("h", "help")
+		c.exitOnHelp = true
+		c.HelpFunc = (*Command).Usage
+	}
 
 	if o.commands == nil {
 		o.commands = make([]*Command, 0)
@@ -144,11 +151,19 @@ func (o *Command) NewCommand(name string, description string) *Command {
 // DisableHelp removes any help arguments from the commands list of arguments
 // This prevents prevents help from being parsed or invoked from the argument list
 func (o *Parser) DisableHelp() {
+	disableHelp = true
 	for i, arg := range o.args {
 		if _, ok := arg.result.(*help); ok {
 			o.args = append(o.args[:i], o.args[i+1:]...)
 		}
 	}
+	for _, com := range o.commands {
+		for i, arg := range com.args {
+			if _, ok := arg.result.(*help); ok {
+				com.args = append(com.args[:i], com.args[i+1:]...)
+			}
+		}
+	}
 }
 
 // ExitOnHelp sets the exitOnHelp variable of Parser
@@ -469,15 +484,16 @@ func message2String(msg interface{}) (string, bool) {
 // getPrecedingCommands - collects info on command chain from root to current (o *Command) and all arguments in this chain
 func (o *Command) getPrecedingCommands(chain *[]string, arguments *[]*arg) {
 	current := o
+	// Also add arguments
 	// Get line of commands until root
 	for current != nil {
 		*chain = append(*chain, current.name)
-		// Also add arguments
 		if current.args != nil {
 			*arguments = append(*arguments, current.args...)
 		}
 		current = current.parent
 	}
+
 	// Reverse the slice
 	last := len(*chain) - 1
 	for i := 0; i < len(*chain)/2; i++ {
@@ -503,6 +519,7 @@ func (o *Command) getSubCommands(chain *[]string) []Command {
 
 // precedingCommands2Result - puts info about command chain from root to current (o *Command) into result string buffer
 func (o *Command) precedingCommands2Result(result string, chain []string, arguments []*arg, maxWidth int) string {
+	usedHelp := false
 	leftPadding := len("usage: " + chain[0] + "")
 	// Add preceding commands
 	for _, v := range chain {
@@ -514,7 +531,13 @@ func (o *Command) precedingCommands2Result(result string, chain []string, argume
 		if v.opts.Help == DisableDescription {
 			continue
 		}
-		result = addToLastLine(result, v.usage(), maxWidth, leftPadding, true)
+		if v.lname == "help" && usedHelp {
+		} else {
+			result = addToLastLine(result, v.usage(), maxWidth, leftPadding, true)
+		}
+		if v.lname == "help" || v.sname == "h" {
+			usedHelp = true
+		}
 	}
 	// Add program/Command description to the result
 	result = result + "\n\n" + strings.Repeat(" ", leftPadding)
@@ -556,6 +579,7 @@ func subCommands2Result(result string, commands []Command, maxWidth int) string
 
 // arguments2Result - puts info about all arguments of current command into result string buffer
 func arguments2Result(result string, arguments []*arg, maxWidth int) string {
+	usedHelp := false
 	if len(arguments) > 0 {
 		argContent := "Arguments:\n\n"
 		// Get biggest padding
@@ -574,18 +598,24 @@ func arguments2Result(result string, arguments []*arg, maxWidth int) string {
 			if argument.opts.Help == DisableDescription {
 				continue
 			}
-			arg := "  "
-			if argument.sname != "" {
-				arg = arg + "-" + argument.sname + "  "
+			if argument.lname == "help" && usedHelp {
 			} else {
-				arg = arg + "    "
+				arg := "  "
+				if argument.sname != "" {
+					arg = arg + "-" + argument.sname + "  "
+				} else {
+					arg = arg + "    "
+				}
+				arg = arg + "--" + argument.lname
+				arg = arg + strings.Repeat(" ", argPadding-len(arg))
+				if argument.opts != nil && argument.opts.Help != "" {
+					arg = addToLastLine(arg, argument.getHelpMessage(), maxWidth, argPadding, true)
+				}
+				argContent = argContent + arg + "\n"
 			}
-			arg = arg + "--" + argument.lname
-			arg = arg + strings.Repeat(" ", argPadding-len(arg))
-			if argument.opts != nil && argument.opts.Help != "" {
-				arg = addToLastLine(arg, argument.getHelpMessage(), maxWidth, argPadding, true)
+			if argument.lname == "help" || argument.sname == "h" {
+				usedHelp = true
 			}
-			argContent = argContent + arg + "\n"
 		}
 		result = result + argContent + "\n"
 	}

argparse_test.go

@@ -1782,18 +1782,17 @@ Arguments:
 
 `
 
-var cmd1Usage = `usage: verylongprogname veryverylongcmd1 [-f|--verylongflag1]
-                        -a|--verylongflagA [-h|--help]
-                        [-s|--verylongstring-flag1 "<value>"]
-                        [-i|--integer-flag1 <integer>]
+var cmd1Usage = `usage: verylongprogname veryverylongcmd1 [-h|--help] [-f|--verylongflag1]
+                        -a|--verylongflagA [-s|--verylongstring-flag1
+                        "<value>"] [-i|--integer-flag1 <integer>]
 
                         cmd1 description
 
 Arguments:
 
+  -h  --help                  Print help information
   -f  --verylongflag1         flag1 description
   -a  --verylongflagA         flag1 description
-  -h  --help                  Print help information
   -s  --verylongstring-flag1  string1 description
   -i  --integer-flag1         integer1 description
 
@@ -2482,20 +2481,20 @@ func TestParserHelpFuncDefault(t *testing.T) {
 func TestCommandHelpFuncDefault(t *testing.T) {
 	parser := NewParser("parser", "")
 	command := parser.NewCommand("command", "")
-	if command.HelpFunc != nil {
+	if command.HelpFunc == nil || command.Help(nil) != command.Usage(nil) {
 		t.Errorf("HelpFunc should default to Usage function")
 	}
 }
 
-func TestCommandHelpFuncDefaultToParent(t *testing.T) {
+func TestCommandHelpFuncOwnFunc(t *testing.T) {
 	parser := NewParser("parser", "")
 	command := parser.NewCommand("command", "")
 
 	parser.HelpFunc = func(c *Command, msg interface{}) string {
 		return "testing"
 	}
 
-	if command.Help(nil) == command.Usage(nil) || command.Help(nil) != parser.Help(nil) {
+	if command.Help(nil) != command.Usage(nil) || command.Help(nil) == parser.Help(nil) {
 		t.Errorf("command HelpFunc should default to parent function")
 	}
 }

command.go

@@ -38,11 +38,13 @@ func (o *Command) addArg(a *arg) error {
 	for current != nil {
 		if current.args != nil {
 			for _, v := range current.args {
-				if a.sname != "" && a.sname == v.sname {
-					return fmt.Errorf("short name %s occurs more than once", a.sname)
-				}
-				if a.lname == v.lname {
-					return fmt.Errorf("long name %s occurs more than once", a.lname)
+				if a.lname != "help" || a.sname != "h" {
+					if a.sname != "" && a.sname == v.sname {
+						return fmt.Errorf("short name %s occurs more than once", a.sname)
+					}
+					if a.lname == v.lname {
+						return fmt.Errorf("long name %s occurs more than once", a.lname)
+					}
 				}
 			}
 		}