Chris@0: <?php
Chris@0: 
Chris@0: /*
Chris@0:  * This file is part of Psy Shell.
Chris@0:  *
Chris@0:  * (c) 2012-2017 Justin Hileman
Chris@0:  *
Chris@0:  * For the full copyright and license information, please view the LICENSE
Chris@0:  * file that was distributed with this source code.
Chris@0:  */
Chris@0: 
Chris@0: namespace Psy\ExecutionLoop;
Chris@0: 
Chris@0: use Psy\Configuration;
Chris@0: use Psy\Exception\BreakException;
Chris@0: use Psy\Exception\ErrorException;
Chris@0: use Psy\Exception\ThrowUpException;
Chris@0: use Psy\Exception\TypeErrorException;
Chris@0: use Psy\Shell;
Chris@0: 
Chris@0: /**
Chris@0:  * The Psy Shell execution loop.
Chris@0:  */
Chris@0: class Loop
Chris@0: {
Chris@0:     const NOOP_INPUT = 'return null;';
Chris@0: 
Chris@0:     /**
Chris@0:      * Loop constructor.
Chris@0:      *
Chris@0:      * The non-forking loop doesn't have much use for Configuration, so we'll
Chris@0:      * just ignore it.
Chris@0:      *
Chris@0:      * @param Configuration $config
Chris@0:      */
Chris@0:     public function __construct(Configuration $config)
Chris@0:     {
Chris@0:         // don't need this
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Run the execution loop.
Chris@0:      *
Chris@0:      * @throws ThrowUpException if thrown by the `throw-up` command
Chris@0:      *
Chris@0:      * @param Shell $shell
Chris@0:      */
Chris@0:     public function run(Shell $shell)
Chris@0:     {
Chris@0:         $loop = function ($__psysh__) {
Chris@0:             // Load user-defined includes
Chris@0:             set_error_handler(array($__psysh__, 'handleError'));
Chris@0:             try {
Chris@0:                 foreach ($__psysh__->getIncludes() as $__psysh_include__) {
Chris@0:                     include $__psysh_include__;
Chris@0:                 }
Chris@0:             } catch (\Exception $_e) {
Chris@0:                 $__psysh__->writeException($_e);
Chris@0:             }
Chris@0:             restore_error_handler();
Chris@0:             unset($__psysh_include__);
Chris@0: 
Chris@0:             extract($__psysh__->getScopeVariables(false));
Chris@0: 
Chris@0:             do {
Chris@0:                 $__psysh__->beforeLoop();
Chris@0:                 $__psysh__->setScopeVariables(get_defined_vars());
Chris@0: 
Chris@0:                 try {
Chris@0:                     // read a line, see if we should eval
Chris@0:                     $__psysh__->getInput();
Chris@0: 
Chris@0:                     // evaluate the current code buffer
Chris@0:                     ob_start(
Chris@0:                         array($__psysh__, 'writeStdout'),
Chris@0:                         version_compare(PHP_VERSION, '5.4', '>=') ? 1 : 2
Chris@0:                     );
Chris@0: 
Chris@0:                     // Let PsySH inject some magic variables back into the
Chris@0:                     // shell scope... things like $__class, and $__file set by
Chris@0:                     // reflection commands
Chris@0:                     extract($__psysh__->getSpecialScopeVariables(false));
Chris@0: 
Chris@0:                     // And unset any magic variables which are no longer needed
Chris@0:                     foreach ($__psysh__->getUnusedCommandScopeVariableNames() as $__psysh_var_name__) {
Chris@0:                         unset($$__psysh_var_name__, $__psysh_var_name__);
Chris@0:                     }
Chris@0: 
Chris@0:                     set_error_handler(array($__psysh__, 'handleError'));
Chris@0:                     $_ = eval($__psysh__->flushCode() ?: Loop::NOOP_INPUT);
Chris@0:                     restore_error_handler();
Chris@0: 
Chris@0:                     ob_end_flush();
Chris@0: 
Chris@0:                     $__psysh__->writeReturnValue($_);
Chris@0:                 } catch (BreakException $_e) {
Chris@0:                     restore_error_handler();
Chris@0:                     if (ob_get_level() > 0) {
Chris@0:                         ob_end_clean();
Chris@0:                     }
Chris@0:                     $__psysh__->writeException($_e);
Chris@0: 
Chris@0:                     return;
Chris@0:                 } catch (ThrowUpException $_e) {
Chris@0:                     restore_error_handler();
Chris@0:                     if (ob_get_level() > 0) {
Chris@0:                         ob_end_clean();
Chris@0:                     }
Chris@0:                     $__psysh__->writeException($_e);
Chris@0: 
Chris@0:                     throw $_e;
Chris@0:                 } catch (\TypeError $_e) {
Chris@0:                     restore_error_handler();
Chris@0:                     if (ob_get_level() > 0) {
Chris@0:                         ob_end_clean();
Chris@0:                     }
Chris@0:                     $__psysh__->writeException(TypeErrorException::fromTypeError($_e));
Chris@0:                 } catch (\Error $_e) {
Chris@0:                     restore_error_handler();
Chris@0:                     if (ob_get_level() > 0) {
Chris@0:                         ob_end_clean();
Chris@0:                     }
Chris@0:                     $__psysh__->writeException(ErrorException::fromError($_e));
Chris@0:                 } catch (\Exception $_e) {
Chris@0:                     restore_error_handler();
Chris@0:                     if (ob_get_level() > 0) {
Chris@0:                         ob_end_clean();
Chris@0:                     }
Chris@0:                     $__psysh__->writeException($_e);
Chris@0:                 }
Chris@0: 
Chris@0:                 $__psysh__->afterLoop();
Chris@0:             } while (true);
Chris@0:         };
Chris@0: 
Chris@0:         // bind the closure to $this from the shell scope variables...
Chris@0:         if (self::bindLoop()) {
Chris@0:             $that = $shell->getBoundObject();
Chris@0:             if (is_object($that)) {
Chris@0:                 $loop = $loop->bindTo($that, get_class($that));
Chris@0:             } else {
Chris@0:                 $loop = $loop->bindTo(null, null);
Chris@0:             }
Chris@0:         }
Chris@0: 
Chris@0:         $loop($shell);
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * A beforeLoop callback.
Chris@0:      *
Chris@0:      * This is executed at the start of each loop iteration. In the default
Chris@0:      * (non-forking) loop implementation, this is a no-op.
Chris@0:      */
Chris@0:     public function beforeLoop()
Chris@0:     {
Chris@0:         // no-op
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * A afterLoop callback.
Chris@0:      *
Chris@0:      * This is executed at the end of each loop iteration. In the default
Chris@0:      * (non-forking) loop implementation, this is a no-op.
Chris@0:      */
Chris@0:     public function afterLoop()
Chris@0:     {
Chris@0:         // no-op
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Decide whether to bind the execution loop.
Chris@0:      *
Chris@0:      * @return bool
Chris@0:      */
Chris@0:     protected static function bindLoop()
Chris@0:     {
Chris@0:         // skip binding on HHVM <= 3.5.0
Chris@0:         // see https://github.com/facebook/hhvm/issues/1203
Chris@0:         if (defined('HHVM_VERSION')) {
Chris@0:             return version_compare(HHVM_VERSION, '3.5.0', '>=');
Chris@0:         }
Chris@0: 
Chris@0:         return version_compare(PHP_VERSION, '5.4', '>=');
Chris@0:     }
Chris@0: }