private function computeUseDef($code)
{
$code = sprintf('<?php function foo($param1, $param2) { %s }', $code);
$ast = \JMS\PhpManipulator\PhpParser\ParseUtils::parse($code);
$scope = (new \Scrutinizer\PhpAnalyzer\PhpParser\Scope\SyntacticScopeCreator())->createScope($ast);
$cfa = new \Scrutinizer\PhpAnalyzer\ControlFlow\ControlFlowAnalysis();
$cfa->process($ast);
$cfg = $cfa->getGraph();
$this->analysis = new \Scrutinizer\PhpAnalyzer\DataFlow\VariableReachability\MayBeReachingUseAnalysis($cfg, $scope);
$this->analysis->analyze();
$this->def = null;
$this->uses = array();
\Scrutinizer\PhpAnalyzer\PhpParser\NodeTraversal::traverseWithCallback($ast, new \Scrutinizer\PhpAnalyzer\PhpParser\PreOrderCallback(function ($t, \PHPParser_Node $node) {
if (!$node instanceof \PHPParser_Node_Stmt_Label) {
return;
}
if ('D' === $node->name) {
$this->def = $node->getAttribute('next');
} else {
if (0 === strpos($node->name, 'U')) {
$this->uses[] = $node->getAttribute('next');
}
}
}));
$this->assertNotNull($this->def);
$this->assertNotEmpty($this->uses);
}
/**
* Returns the inferred return type for the given function.
*
* If we cannot infer any type NO type is returned, this is also returned if we can only infer
* ALL type, or UNKNOWN type.
*
* We use two characteristics for inferring a return type. First, we are looking at how the
* return value of the function is used in the places from where it is called. Currently, we
* are only looking at whether it is passed to other functions/methods and what their expected
* parameter types are.
*
* Second, we also take a look at the exit points of the CFG of the function itself to see
* whether there are some specific types which we can infer. For example, a function might return
* NULL type, or ALL type in which case its return type would normally be set to ALL type.
* However, for our analysis here, we just ignore the ALL type, and add the NULL type to the
* list of allowed types.
*
* @param AbstractFunction $function
*
* @return PhpType
*/
private function inferReturnTypeForFunction(AbstractFunction $function, MethodContainer $container = null)
{
$types = array();
if ($container instanceof \Scrutinizer\PhpAnalyzer\Model\InterfaceC) {
foreach ($container->getImplementingClasses() as $class) {
if (null === ($implementedFunction = $class->getMethod($function->getName()))) {
continue;
}
$returnType = $implementedFunction->getReturnType();
if ($returnType->isUnknownType() || $returnType->isAllType()) {
continue;
}
$types[] = $returnType;
}
}
if (!$types) {
foreach ($function->getInCallSites() as $site) {
// We can only analyze call sites which are part of the code which is currently being
// scanned. Otherwise, we would need to persist the possible types to the database.
// This could be a future improvement though if we deem it necessary.
if (null === ($node = $site->getAstNode())) {
continue;
}
if (null === ($parent = $node->getAttribute('parent'))) {
continue;
}
switch (true) {
case $parent instanceof \PHPParser_Node_Arg:
if (null === ($callNode = $parent->getAttribute('parent'))) {
break;
}
$paramType = $this->getSpecificParamTypeForArg($callNode, $parent);
if ($paramType) {
$types[] = $paramType;
}
break;
case $parent instanceof \PHPParser_Node_Expr_Assign:
case $parent instanceof \PHPParser_Node_Expr_AssignRef:
foreach ($parent->var->getAttribute('maybe_using_vars', array()) as $varNode) {
if (null === ($argNode = $varNode->getAttribute('parent'))) {
continue;
}
if (!$argNode instanceof \PHPParser_Node_Arg) {
continue;
}
$callNode = $argNode->getAttribute('parent');
$paramType = $this->getSpecificParamTypeForArg($callNode, $argNode);
if (null !== $paramType) {
$types[] = $paramType;
}
}
break;
}
}
}
$cfa = new \Scrutinizer\PhpAnalyzer\ControlFlow\ControlFlowAnalysis();
$cfa->process($function->getAstNode());
$cfg = $cfa->getGraph();
foreach ($cfg->getDirectedSuccNodes($cfg->getImplicitReturn()) as $exitGraphNode) {
$exitNode = $exitGraphNode->getAstNode();
if (!$exitNode instanceof \PHPParser_Node_Stmt_Return || null === $exitNode->expr) {
$types[] = $this->registry->getNativeType('null');
continue;
}
$returnType = $exitNode->expr->getAttribute('type');
if ($returnType && !$returnType->isUnknownType() && !$returnType->isAllType()) {
$types[] = $returnType;
}
}
return $this->refineTypeForAnnotation($this->registry->createUnionType($types), true);
}