Refactor CLI code and add tests

Author: Planeshifter

lib/node_modules/@stdlib/namespace/bin/cli

@@ -22,144 +22,109 @@
 
 // MODULES //
 
-var fs = require( 'fs' );
-var path = require( 'path' );
-var parseArgs = require( 'minimist' );
+var resolve = require( 'path' ).resolve;
+var readFileSync = require( '@stdlib/fs/read-file' ).sync;
 var indexOf = require( '@stdlib/utils/index-of' );
-var pkg = require( './../package.json' );
-var opts = require( './opts.json' );
-var main = require( './../lib' );
+var CLI = require( '@stdlib/cli/ctor' );
+var namespace = require( './../lib' );
 
 
-// FUNCTIONS //
+// VARIABLES //
 
-/**
-* Performs initialization tasks.
-*
-* @private
-* @example
-* init();
-*/
-function init() {
-	// Set the process title to allow the process to be more easily identified:
-	process.title = pkg.name;
-	process.stdout.on( 'error', process.exit );
-}
+var FIELDS = [ 'alias', 'path', 'type', 'related' ];
 
-/**
-* Prints usage information.
-*
-* @private
-* @example
-* help();
-* // => '...'
-*/
-function help() {
-	var fpath = path.join( __dirname, 'usage.txt' );
-	fs.createReadStream( fpath )
-		.pipe( process.stderr )
-		.on( 'close', onClose );
-
-	function onClose() {
-		process.exit( 0 );
-	}
-}
 
-/**
-* Prints the package version.
-*
-* @private
-* @example
-* version();
-* // => '#.#.#'
-*/
-function version() {
-	var msg = pkg.version.toString()+'\n';
-	process.stdout.write( msg, 'utf8' );
-	process.exit( 0 );
-}
+// MAIN //
 
 /**
-* Prints data as newline-delimited JSON (ndjson).
+* Main execution sequence.
 *
 * @private
-* @param {ObjectArray} data - data to print
+* @throws {Error} unrecognized/unsupported field
+* @returns {void}
 */
-function ndjson( data ) {
+function main() {
+	var fields;
+	var flags;
+	var cli;
 	var i;
 
-	for ( i = 0; i < data.length; i++ ) {
-		console.log( JSON.stringify( data[i] ) );
+	// Create a command-line interface:
+	cli = new CLI({
+		'pkg': require( './../package.json' ),
+		'options': require( './../etc/cli_opts.json' ),
+		'help': readFileSync( resolve( __dirname, '..', 'docs', 'usage.txt' ), {
+			'encoding': 'utf8'
+		})
+	});
+
+	// Get any provided command-line options:
+	flags = cli.flags();
+	if ( flags.help || flags.version ) {
+		return;
 	}
-}
-
-/**
-* Prints data as lines of comma-separated values (CSV).
-*
-* @private
-* @param {ObjectArray} data - data to print
-* @param {StringArray} fields - output fields
-*/
-function csv( data, fields ) {
-	var line;
-	var f;
-	var i;
-	var j;
-	var n;
-	var m;
-
-	n = fields.length;
-	m = n - 1;
-	line = '';
-	for ( j = 0; j < n; j++ ) {
-		line += '"' + fields[ j ] + '"';
-		if ( j < m ) {
-			line += ',';
+	if ( flags.fields ) {
+		fields = flags.fields.split( ',' );
+		for ( i = 0; i < fields.length; i++ ) {
+			if ( indexOf( FIELDS, fields[ i ] ) === -1 ) {
+				throw new Error( 'invalid option. Unrecognized/unsupported field. Option: `' + fields[ i ] + '`.' );
+			}
 		}
+		return csv( namespace(), fields );
 	}
-	console.log( line );
-	for ( i = 0; i < data.length; i++ ) {
+	ndjson( namespace() );
+
+	/**
+	* Prints data as newline-delimited JSON (ndjson).
+	*
+	* @private
+	* @param {ObjectArray} data - data to print
+	*/
+	function ndjson( data ) {
+		var i;
+
+		for ( i = 0; i < data.length; i++ ) {
+			console.log( JSON.stringify( data[i] ) );
+		}
+	}
+
+	/**
+	* Prints data as lines of comma-separated values (CSV).
+	*
+	* @private
+	* @param {ObjectArray} data - data to print
+	* @param {StringArray} fields - output fields
+	*/
+	function csv( data, fields ) {
+		var line;
+		var f;
+		var i;
+		var j;
+		var n;
+		var m;
+
+		n = fields.length;
+		m = n - 1;
 		line = '';
 		for ( j = 0; j < n; j++ ) {
-			f = fields[ j ];
-			line += '"' + data[ i ][ f ] + '"';
+			line += '"' + fields[ j ] + '"';
 			if ( j < m ) {
 				line += ',';
 			}
 		}
 		console.log( line );
-	}
-}
-
-
-// VARIABLES //
-
-var FIELDS = [ 'alias', 'path', 'type', 'related' ];
-var fields;
-var args;
-var i;
-
-
-// MAIN //
-
-init();
-
-// Parse command-line arguments:
-args = parseArgs( process.argv.slice( 2 ), opts );
-
-if ( args.help ) {
-	return help();
-}
-if ( args.version ) {
-	return version();
-}
-if ( args.fields ) {
-	fields = args.fields.split( ',' );
-	for ( i = 0; i < fields.length; i++ ) {
-		if ( indexOf( FIELDS, fields[ i ] ) === -1 ) {
-			throw new Error( 'invalid option. Unrecognized/unsupported field. Option: `' + fields[ i ] + '`.' );
+		for ( i = 0; i < data.length; i++ ) {
+			line = '';
+			for ( j = 0; j < n; j++ ) {
+				f = fields[ j ];
+				line += '"' + data[ i ][ f ] + '"';
+				if ( j < m ) {
+					line += ',';
+				}
+			}
+			console.log( line );
 		}
 	}
-	return csv( main(), fields );
 }
-ndjson( main() );
+
+main();