www.aleph1.co.uk Git - yaffs-website/blob - vendor/psy/psysh/src/Psy/ExecutionLoop/Loop.php

   1 <?php
   2
   3 /*
   4  * This file is part of Psy Shell.
   5  *
   6  * (c) 2012-2017 Justin Hileman
   7  *
   8  * For the full copyright and license information, please view the LICENSE
   9  * file that was distributed with this source code.
  10  */
  11
  12 namespace Psy\ExecutionLoop;
  13
  14 use Psy\Configuration;
  15 use Psy\Exception\BreakException;
  16 use Psy\Exception\ErrorException;
  17 use Psy\Exception\ThrowUpException;
  18 use Psy\Exception\TypeErrorException;
  19 use Psy\Shell;
  20
  21 /**
  22  * The Psy Shell execution loop.
  23  */
  24 class Loop
  25 {
  26     const NOOP_INPUT = 'return null;';
  27
  28     /**
  29      * Loop constructor.
  30      *
  31      * The non-forking loop doesn't have much use for Configuration, so we'll
  32      * just ignore it.
  33      *
  34      * @param Configuration $config
  35      */
  36     public function __construct(Configuration $config)
  37     {
  38         // don't need this
  39     }
  40
  41     /**
  42      * Run the execution loop.
  43      *
  44      * @throws ThrowUpException if thrown by the `throw-up` command
  45      *
  46      * @param Shell $shell
  47      */
  48     public function run(Shell $shell)
  49     {
  50         $loop = function ($__psysh__) {
  51             // Load user-defined includes
  52             set_error_handler(array($__psysh__, 'handleError'));
  53             try {
  54                 foreach ($__psysh__->getIncludes() as $__psysh_include__) {
  55                     include $__psysh_include__;
  56                 }
  57             } catch (\Exception $_e) {
  58                 $__psysh__->writeException($_e);
  59             }
  60             restore_error_handler();
  61             unset($__psysh_include__);
  62
  63             extract($__psysh__->getScopeVariables(false));
  64
  65             do {
  66                 $__psysh__->beforeLoop();
  67                 $__psysh__->setScopeVariables(get_defined_vars());
  68
  69                 try {
  70                     // read a line, see if we should eval
  71                     $__psysh__->getInput();
  72
  73                     // evaluate the current code buffer
  74                     ob_start(
  75                         array($__psysh__, 'writeStdout'),
  76                         version_compare(PHP_VERSION, '5.4', '>=') ? 1 : 2
  77                     );
  78
  79                     // Let PsySH inject some magic variables back into the
  80                     // shell scope... things like $__class, and $__file set by
  81                     // reflection commands
  82                     extract($__psysh__->getSpecialScopeVariables(false));
  83
  84                     // And unset any magic variables which are no longer needed
  85                     foreach ($__psysh__->getUnusedCommandScopeVariableNames() as $__psysh_var_name__) {
  86                         unset($$__psysh_var_name__, $__psysh_var_name__);
  87                     }
  88
  89                     set_error_handler(array($__psysh__, 'handleError'));
  90                     $_ = eval($__psysh__->flushCode() ?: Loop::NOOP_INPUT);
  91                     restore_error_handler();
  92
  93                     ob_end_flush();
  94
  95                     $__psysh__->writeReturnValue($_);
  96                 } catch (BreakException $_e) {
  97                     restore_error_handler();
  98                     if (ob_get_level() > 0) {
  99                         ob_end_clean();
 100                     }
 101                     $__psysh__->writeException($_e);
 102
 103                     return;
 104                 } catch (ThrowUpException $_e) {
 105                     restore_error_handler();
 106                     if (ob_get_level() > 0) {
 107                         ob_end_clean();
 108                     }
 109                     $__psysh__->writeException($_e);
 110
 111                     throw $_e;
 112                 } catch (\TypeError $_e) {
 113                     restore_error_handler();
 114                     if (ob_get_level() > 0) {
 115                         ob_end_clean();
 116                     }
 117                     $__psysh__->writeException(TypeErrorException::fromTypeError($_e));
 118                 } catch (\Error $_e) {
 119                     restore_error_handler();
 120                     if (ob_get_level() > 0) {
 121                         ob_end_clean();
 122                     }
 123                     $__psysh__->writeException(ErrorException::fromError($_e));
 124                 } catch (\Exception $_e) {
 125                     restore_error_handler();
 126                     if (ob_get_level() > 0) {
 127                         ob_end_clean();
 128                     }
 129                     $__psysh__->writeException($_e);
 130                 }
 131
 132                 $__psysh__->afterLoop();
 133             } while (true);
 134         };
 135
 136         // bind the closure to $this from the shell scope variables...
 137         if (self::bindLoop()) {
 138             $that = $shell->getBoundObject();
 139             if (is_object($that)) {
 140                 $loop = $loop->bindTo($that, get_class($that));
 141             } else {
 142                 $loop = $loop->bindTo(null, null);
 143             }
 144         }
 145
 146         $loop($shell);
 147     }
 148
 149     /**
 150      * A beforeLoop callback.
 151      *
 152      * This is executed at the start of each loop iteration. In the default
 153      * (non-forking) loop implementation, this is a no-op.
 154      */
 155     public function beforeLoop()
 156     {
 157         // no-op
 158     }
 159
 160     /**
 161      * A afterLoop callback.
 162      *
 163      * This is executed at the end of each loop iteration. In the default
 164      * (non-forking) loop implementation, this is a no-op.
 165      */
 166     public function afterLoop()
 167     {
 168         // no-op
 169     }
 170
 171     /**
 172      * Decide whether to bind the execution loop.
 173      *
 174      * @return bool
 175      */
 176     protected static function bindLoop()
 177     {
 178         // skip binding on HHVM <= 3.5.0
 179         // see https://github.com/facebook/hhvm/issues/1203
 180         if (defined('HHVM_VERSION')) {
 181             return version_compare(HHVM_VERSION, '3.5.0', '>=');
 182         }
 183
 184         return version_compare(PHP_VERSION, '5.4', '>=');
 185     }
 186 }