/**
* @param Context $context
* The context in which the node appears
*
* @param CodeBase $code_base
*
* @param Node $node
* An AST node representing a function
*
* @return Func
* A Func representing the AST node in the
* given context
*/
public static function fromNode(Context $context, CodeBase $code_base, Decl $node) : Func
{
// Parse the comment above the function to get
// extra meta information about the function.
$comment = Comment::fromStringInContext($node->docComment ?? '', $context);
// @var Parameter[]
// The list of parameters specified on the
// function
$parameter_list = Parameter::listFromNode($context, $code_base, $node->children['params']);
// Add each parameter to the scope of the function
foreach ($parameter_list as $parameter) {
$context = $context->withScopeVariable($parameter);
}
// Create the skeleton function object from what
// we know so far
$func = new Func($context, (string) $node->name, new UnionType(), $node->flags ?? 0);
// If the function is Analyzable, set the node so that
// we can come back to it whenever we like and
// rescan it
$func->setNode($node);
// Set the parameter list on the function
$func->setParameterList($parameter_list);
$func->setNumberOfRequiredParameters(array_reduce($parameter_list, function (int $carry, Parameter $parameter) : int {
return $carry + ($parameter->isRequired() ? 1 : 0);
}, 0));
$func->setNumberOfOptionalParameters(array_reduce($parameter_list, function (int $carry, Parameter $parameter) : int {
return $carry + ($parameter->isOptional() ? 1 : 0);
}, 0));
// Check to see if the comment specifies that the
// function is deprecated
$func->setIsDeprecated($comment->isDeprecated());
$func->setSuppressIssueList($comment->getSuppressIssueList());
// Take a look at function return types
if ($node->children['returnType'] !== null) {
// Get the type of the parameter
$union_type = UnionType::fromNode($context, $code_base, $node->children['returnType']);
$func->getUnionType()->addUnionType($union_type);
}
if ($comment->hasReturnUnionType()) {
// See if we have a return type specified in the comment
$union_type = $comment->getReturnType();
assert(!$union_type->hasSelfType(), "Function referencing self in {$context}");
$func->getUnionType()->addUnionType($union_type);
}
// Add params to local scope for user functions
if (!$func->isInternal()) {
$parameter_offset = 0;
foreach ($func->getParameterList() as $i => $parameter) {
if ($parameter->getUnionType()->isEmpty()) {
// If there is no type specified in PHP, check
// for a docComment with @param declarations. We
// assume order in the docComment matches the
// parameter order in the code
if ($comment->hasParameterWithNameOrOffset($parameter->getName(), $parameter_offset)) {
$comment_type = $comment->getParameterWithNameOrOffset($parameter->getName(), $parameter_offset)->getUnionType();
$parameter->getUnionType()->addUnionType($comment_type);
}
}
// If there's a default value on the parameter, check to
// see if the type of the default is cool with the
// specified type.
if ($parameter->hasDefaultValue()) {
$default_type = $parameter->getDefaultValueType();
if (!$default_type->isEqualTo(NullType::instance()->asUnionType())) {
if (!$default_type->isEqualTo(NullType::instance()->asUnionType()) && !$default_type->canCastToUnionType($parameter->getUnionType())) {
Issue::maybeEmit($code_base, $context, Issue::TypeMismatchDefault, $node->lineno ?? 0, (string) $parameter->getUnionType(), $parameter->getName(), (string) $default_type);
}
$parameter->getUnionType()->addUnionType($default_type);
}
// If we have no other type info about a parameter,
// just because it has a default value of null
// doesn't mean that is its type. Any type can default
// to null
if ((string) $default_type === 'null' && !$parameter->getUnionType()->isEmpty()) {
$parameter->getUnionType()->addType(NullType::instance());
}
}
++$parameter_offset;
}
}
return $func;
}
