Adding a ghetto start to what will be the 2.0 upgrade shell. i18n updating mostly works.

cake/console/shells/upgrade.php

@@ -0,0 +1,90 @@
+<?php
+/**
+ * A shell class to help developers upgrade applications to CakePHP 2.0
+ *
+ * @package cake.console/shells
+ */
+class UpgradeShell extends Shell {
+
+	protected $_files = array();
+	protected $_paths = array();
+/**
+ * Update i18n.
+ *
+ * - Removes extra true param.
+ *
+ * @return void
+ */
+	function i18n() {
+		if ($this->params['plugin']) {
+			$this->_paths = array(App::pluginPath($this->params['plugin']));
+		}
+		$this->_findFiles();
+		foreach ($this->_files as $file) {
+			$this->out('Updating ' . $file . '...', 1, Shell::VERBOSE);
+			$this->_updateFile($file);
+		}
+	}
+
+	protected function _findFiles() {
+		foreach ($this->_paths as $path) {
+			$Folder = new Folder($path);
+			$files = $Folder->findRecursive('.*\.(php|ctp|thtml|inc|tpl)', true);
+			if (!empty($pattern)) {
+				foreach ($files as $i => $file) {
+					if (preg_match($pattern, $file)) {
+						unset($files[$i]);
+					}
+				}
+				$files = array_values($files);
+			}
+			$this->_files = array_merge($this->_files, $files);
+		}
+	}
+
+/**
+ * Update a single file.
+ *
+ * @return void
+ */
+	protected function _updateFile($file) {
+		$contents = file_get_contents($file);
+		$patterns = array(
+			array(
+				'<?php __*(*) to <?php echo __*(*)',
+				'/<\?php\s*(__[a-z]*\(.*?\))/',
+				'<?php echo \1'
+			),
+			array(
+				'<?php __*(*, true) to <?php echo __*()',
+				'/<\?php\s*(__[a-z]*\(.*?)(,\s*true)(\))/',
+				'<?php echo \1\3'
+			),
+			array('__*(*, true) to __*(*)', '/(__[a-z]*\(.*?)(,\s*true)(\))/', '\1\3')
+		);
+		foreach ($patterns as $pattern) {
+			$this->out(' * Updating ' . $pattern[0], 1, Shell::VERBOSE);
+			$contents = preg_replace($pattern[1], $pattern[2], $contents);
+		}
+
+		$this->out('Done updating ' . $file, 1);
+		file_put_contents($file, $contents);
+	}
+
+/**
+ * get the option parser
+ *
+ * @return void
+ */
+	function getOptionParser() {
+		return parent::getOptionParser()
+			->addSubcommand('i18n', array(
+				'help' => 'Update the i18n translation method calls.',
+				'parser' => array(
+					'options' => array(
+						'plugin' => array('short' => 'p', 'help' => __('The plugin to update.'))
+					)
+				)
+			));
+	}
+}