Chris@13: <?php
Chris@13: 
Chris@13: /*
Chris@13:  * This file is part of Psy Shell.
Chris@13:  *
Chris@13:  * (c) 2012-2018 Justin Hileman
Chris@13:  *
Chris@13:  * For the full copyright and license information, please view the LICENSE
Chris@13:  * file that was distributed with this source code.
Chris@13:  */
Chris@13: 
Chris@13: namespace Psy\CodeCleaner;
Chris@13: 
Chris@13: use PhpParser\Node;
Chris@13: use PhpParser\Node\Expr;
Chris@13: use PhpParser\Node\Expr\FuncCall;
Chris@13: use PhpParser\Node\Expr\Variable;
Chris@13: use PhpParser\Node\Stmt\Do_;
Chris@13: use PhpParser\Node\Stmt\Function_;
Chris@13: use PhpParser\Node\Stmt\If_;
Chris@13: use PhpParser\Node\Stmt\Switch_;
Chris@13: use PhpParser\Node\Stmt\While_;
Chris@13: use Psy\Exception\FatalErrorException;
Chris@13: 
Chris@13: /**
Chris@13:  * Validate that function calls will succeed.
Chris@13:  *
Chris@13:  * This pass throws a FatalErrorException rather than letting PHP run
Chris@13:  * headfirst into a real fatal error and die.
Chris@13:  */
Chris@13: class ValidFunctionNamePass extends NamespaceAwarePass
Chris@13: {
Chris@13:     private $conditionalScopes = 0;
Chris@13: 
Chris@13:     /**
Chris@13:      * Store newly defined function names on the way in, to allow recursion.
Chris@13:      *
Chris@13:      * @param Node $node
Chris@13:      */
Chris@13:     public function enterNode(Node $node)
Chris@13:     {
Chris@13:         parent::enterNode($node);
Chris@13: 
Chris@13:         if (self::isConditional($node)) {
Chris@13:             $this->conditionalScopes++;
Chris@13:         } elseif ($node instanceof Function_) {
Chris@13:             $name = $this->getFullyQualifiedName($node->name);
Chris@13: 
Chris@13:             // @todo add an "else" here which adds a runtime check for instances where we can't tell
Chris@13:             // whether a function is being redefined by static analysis alone.
Chris@13:             if ($this->conditionalScopes === 0) {
Chris@13:                 if (function_exists($name) ||
Chris@13:                     isset($this->currentScope[strtolower($name)])) {
Chris@13:                     $msg = sprintf('Cannot redeclare %s()', $name);
Chris@13:                     throw new FatalErrorException($msg, 0, E_ERROR, null, $node->getLine());
Chris@13:                 }
Chris@13:             }
Chris@13: 
Chris@13:             $this->currentScope[strtolower($name)] = true;
Chris@13:         }
Chris@13:     }
Chris@13: 
Chris@13:     /**
Chris@13:      * Validate that function calls will succeed.
Chris@13:      *
Chris@13:      * @throws FatalErrorException if a function is redefined
Chris@13:      * @throws FatalErrorException if the function name is a string (not an expression) and is not defined
Chris@13:      *
Chris@13:      * @param Node $node
Chris@13:      */
Chris@13:     public function leaveNode(Node $node)
Chris@13:     {
Chris@13:         if (self::isConditional($node)) {
Chris@13:             $this->conditionalScopes--;
Chris@13:         } elseif ($node instanceof FuncCall) {
Chris@13:             // if function name is an expression or a variable, give it a pass for now.
Chris@13:             $name = $node->name;
Chris@13:             if (!$name instanceof Expr && !$name instanceof Variable) {
Chris@13:                 $shortName = implode('\\', $name->parts);
Chris@13:                 $fullName  = $this->getFullyQualifiedName($name);
Chris@13:                 $inScope   = isset($this->currentScope[strtolower($fullName)]);
Chris@13:                 if (!$inScope && !function_exists($shortName) && !function_exists($fullName)) {
Chris@13:                     $message = sprintf('Call to undefined function %s()', $name);
Chris@13:                     throw new FatalErrorException($message, 0, E_ERROR, null, $node->getLine());
Chris@13:                 }
Chris@13:             }
Chris@13:         }
Chris@13:     }
Chris@13: 
Chris@13:     private static function isConditional(Node $node)
Chris@13:     {
Chris@13:         return $node instanceof If_ ||
Chris@13:             $node instanceof While_ ||
Chris@13:             $node instanceof Do_ ||
Chris@13:             $node instanceof Switch_;
Chris@13:     }
Chris@13: }