--- /dev/null
+<?php
+
+/*
+ * This file is part of Psy Shell.
+ *
+ * (c) 2012-2017 Justin Hileman
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Psy\Command;
+
+use Symfony\Component\Console\Helper\TableHelper;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+/**
+ * Help command.
+ *
+ * Lists available commands, and gives command-specific help when asked nicely.
+ */
+class HelpCommand extends Command
+{
+ private $command;
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function configure()
+ {
+ $this
+ ->setName('help')
+ ->setAliases(array('?'))
+ ->setDefinition(array(
+ new InputArgument('command_name', InputArgument::OPTIONAL, 'The command name', null),
+ ))
+ ->setDescription('Show a list of commands. Type `help [foo]` for information about [foo].')
+ ->setHelp('My. How meta.');
+ }
+
+ /**
+ * Helper for setting a subcommand to retrieve help for.
+ *
+ * @param Command $command
+ */
+ public function setCommand($command)
+ {
+ $this->command = $command;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function execute(InputInterface $input, OutputInterface $output)
+ {
+ if ($this->command !== null) {
+ // help for an individual command
+ $output->page($this->command->asText());
+ $this->command = null;
+ } elseif ($name = $input->getArgument('command_name')) {
+ // help for an individual command
+ $output->page($this->getApplication()->get($name)->asText());
+ } else {
+ // list available commands
+ $commands = $this->getApplication()->all();
+
+ $table = $this->getTable($output);
+
+ foreach ($commands as $name => $command) {
+ if ($name !== $command->getName()) {
+ continue;
+ }
+
+ if ($command->getAliases()) {
+ $aliases = sprintf('<comment>Aliases:</comment> %s', implode(', ', $command->getAliases()));
+ } else {
+ $aliases = '';
+ }
+
+ $table->addRow(array(
+ sprintf('<info>%s</info>', $name),
+ $command->getDescription(),
+ $aliases,
+ ));
+ }
+
+ $output->startPaging();
+ if ($table instanceof TableHelper) {
+ $table->render($output);
+ } else {
+ $table->render();
+ }
+ $output->stopPaging();
+ }
+ }
+}