In copy_dir(), use cp -R on Mac, cp -r everywhere else (#183)

* In `copy_dir()`, use `cp -R` on Mac, `cp -r` everywhere else

* Separate the shell command

Co-authored-by: Alain Schlesser <[email protected]>

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Co-authored-by: Alain Schlesser <[email protected]>

Author: danielbachhuber

src/Context/FeatureContext.php

@@ -824,7 +824,10 @@ public static function remove_dir( $dir ) {
 	 * Copy a directory (recursive). Destination directory must exist.
 	 */
 	public static function copy_dir( $src_dir, $dest_dir ) {
-		Process::create( Utils\esc_cmd( 'cp -r %s/* %s', $src_dir, $dest_dir ) )->run_check();
+		$shell_command = ( 'Darwin' === PHP_OS )
+			? Utils\esc_cmd( 'cp -R %s/* %s', $src_dir, $dest_dir )
+			: Utils\esc_cmd( 'cp -r %s/* %s', $src_dir, $dest_dir );
+		Process::create( $shell_command )->run_check();
 	}
 
 	public function add_line_to_wp_config( &$wp_config_code, $line ) {