| ⇢ | A | VariablesInAllowedPositionRule added | |
| ⇢ | A | TypeComparator added | 
| ⇢ | C | TypeComparator::isTypeSubtypeOf() added | |
| ⇢ | C | VariablesInAllowedPositionRule::leaveNode() added | |
| ⇢ | B | TypeComparator::doTypesOverlap() added | |
| ⇢ | A | badVariablePositionMessage() added | |
| ⇢ | A | VariablesInAllowedPositionRule::enterNode() added | |
| ⇢ | A | VariablesInAllowedPositionRule::getEffectiveType() added | |
| ⇢ | A | PossibleFragmentSpreadsRule::__construct() added | |
| ⇢ | A | DefaultValueTrait::hasDefaultValue() added | |
| ⇢ | A | VariablesInAllowedPositionRule::__construct() added | |
| B | ↛ | doTypesOverlap() removed |