From 9d09eb220cfc9a6ad259fe616cd22790137a3906 Mon Sep 17 00:00:00 2001
From: "Alex A. Naanou" <alex.nanou@gmail.com>
Date: Thu, 10 Dec 2020 15:33:36 +0300
Subject: [PATCH] added required arg info in .usage info...

Signed-off-by: Alex A. Naanou <alex.nanou@gmail.com>
---
 README.md    | 40 ++++++++++++++++++++--------------------
 argv.js      | 30 ++++++++++++++++++++++++++++--
 package.json |  2 +-
 3 files changed, 49 insertions(+), 23 deletions(-)

diff --git a/README.md b/README.md
index c4e8d63..82b49f7 100644
--- a/README.md
+++ b/README.md
@@ -51,25 +51,25 @@ This code is an evolution of that parser.
 
 ## Contents
 - [argv.js](#argvjs)
-	- [Motivation](#motivation)
-	- [Features](#features)
-		- [Planned](#planned)
-	- [Contents](#contents)
-	- [Architecture](#architecture)
-	- [Basics and quick start](#basics-and-quick-start)
-	- [Options in more detail](#options-in-more-detail)
-		- [Help and metadata](#help-and-metadata)
-		- [Basic options](#basic-options)
-		- [Commands](#commands)
-		- [Active options/commands](#active-optionscommands)
-		- [Nested parsers](#nested-parsers)
-		- [Stopping](#stopping)
-		- [Error reporting](#error-reporting)
-		- [Before parsing begins](#before-parsing-begins)
-		- [Handling the result](#handling-the-result)
-		- [Calling the script](#calling-the-script)
-	- [Advanced docs](#advanced-docs)
-	- [License](#license)
+  - [Motivation](#motivation)
+  - [Features](#features)
+    - [Planned](#planned)
+  - [Contents](#contents)
+  - [Architecture](#architecture)
+  - [Basics and quick start](#basics-and-quick-start)
+  - [Options in more detail](#options-in-more-detail)
+    - [Help and metadata](#help-and-metadata)
+    - [Basic options](#basic-options)
+    - [Commands](#commands)
+    - [Active options/commands](#active-optionscommands)
+    - [Nested parsers](#nested-parsers)
+    - [Stopping](#stopping)
+    - [Error reporting](#error-reporting)
+    - [Before parsing begins](#before-parsing-begins)
+    - [Handling the result](#handling-the-result)
+    - [Calling the script](#calling-the-script)
+  - [Advanced docs](#advanced-docs)
+  - [License](#license)
 
 
 ## Architecture
@@ -528,7 +528,7 @@ The `<parser>` will call different sets of callbacks on different stop condition
 This will create a parser that supports the following:
 ```shell_session
 $ ./options.js --help 
-Usage: options.js [OPTIONS]
+Usage: options.js -r [OPTIONS]
 
 Example script options
 
diff --git a/argv.js b/argv.js
index dfd6944..a292a00 100644
--- a/argv.js
+++ b/argv.js
@@ -629,7 +629,7 @@ object.Constructor('Parser', {
 				Object.values(o).join(' ')
 				: o }),
 	license: getFromPackage('license'),
-	usage: '$SCRIPTNAME [OPTIONS]',
+	usage: '$SCRIPTNAME $REQUIRED [OPTIONS]',
 	doc: undefined,
 	examples: undefined,
 	//footer: undefined,
@@ -648,6 +648,14 @@ object.Constructor('Parser', {
 			: [a] },
 	// NOTE: if var value is not defined here we'll try and get it from 
 	// 		parent...
+	// NOTE: this tries to be smart with spaces around $REQUIRED so 
+	// 		as to keep it natural in the format string while removing 
+	// 		the extra space when no value is present...
+	// 			'script $REQUIRED args'
+	// 		can produce:
+	// 			'script args'
+	// 			'script x=VALUE args'
+	// 		depending on required options...
 	expandTextVars: function(text){
 		var that = this
 		var get = function(o, attr, dfl){
@@ -657,11 +665,29 @@ object.Constructor('Parser', {
 				|| (o.parent ? 
 					get(o.parent, attr, dfl)
 	   				: dfl )}
+		// NOTE: this can get a bit expensive so we check if we need the 
+		// 		value before generating it...
+		text = /\$REQUIRED/g.test(text) ?
+			// add required args and values...
+			text
+				.replace(/ ?\$REQUIRED ?/g, 
+					that.requiredArguments()
+						.map(function([[key], arg]){
+							key = key.startsWith(COMMAND_PREFIX) ?
+								key.slice(COMMAND_PREFIX.length)
+								: key
+							return ' '
+								+(arg ?
+									key+'='+arg
+									: key) })
+						.join('')
+					+' ')
+			: text
 		return text
 			.replace(/\$AUTHOR/g, get(that, 'author', 'Author'))
 			.replace(/\$LICENSE/g, get(that, 'license', '-'))
 			.replace(/\$VERSION/g, get(that, 'version', '0.0.0'))
-			.replace(/\$SCRIPTNAME/g, this.scriptName) },
+			.replace(/\$SCRIPTNAME/g, this.scriptName || 'SCRIPT') },
 
 	// NOTE: this will set .quiet to false...
 	'-h': '-help',
diff --git a/package.json b/package.json
index 1a07ea6..b68aa48 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "ig-argv",
-  "version": "2.15.6",
+  "version": "2.15.7",
   "description": "simple argv parser",
   "main": "argv.js",
   "scripts": {