private function restrictByValueType(PhpType $type = null, $outcome, $typeName)
{
// If the type function evaluates to true, we can always say what
// the type is afterwards even if we do not know the input.
if ($outcome) {
return $this->typeRegistry->getNativeType($typeName);
}
if (null === $type) {
return null;
}
// If we know the outcome is false, and only the given type is passed,
// e.g. is_array() receives only arrays, then this condition always
// evaluates to false.
if ($type->{'is' . $typeName . 'Type'}()) {
return $this->typeRegistry->getNativeType('none');
}
// If a union type is passed, the value can be whatever the union type
// represents minus the checked type.
if ($type->isUnionType()) {
return $type->getRestrictedUnion($this->typeRegistry->getNativeType($typeName));
}
// If an all type is passed, the value can be all value types minus the
// checked value type.
if ($type->isAllType()) {
$allTypes = array('object', 'integer', 'double', 'string', 'null', 'array', 'boolean');
unset($allTypes[array_search($typeName, $allTypes, true)]);
return $this->typeRegistry->createUnionType($allTypes);
}
// If nothing from above is applicable, just return the type. It is an
// indication that the condition is always false, for example
// is_array() receives always non-array values.
return $type;
}