luau/Analysis/include/Luau/Constraint.h
2023-02-10 10:50:54 -08:00

209 lines
4.8 KiB
C++

// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
#pragma once
#include "Luau/Ast.h" // Used for some of the enumerations
#include "Luau/Def.h"
#include "Luau/DenseHash.h"
#include "Luau/NotNull.h"
#include "Luau/Type.h"
#include "Luau/Variant.h"
#include <string>
#include <memory>
#include <vector>
namespace Luau
{
struct Scope;
struct Type;
using TypeId = const Type*;
struct TypePackVar;
using TypePackId = const TypePackVar*;
// subType <: superType
struct SubtypeConstraint
{
TypeId subType;
TypeId superType;
};
// subPack <: superPack
struct PackSubtypeConstraint
{
TypePackId subPack;
TypePackId superPack;
};
// generalizedType ~ gen sourceType
struct GeneralizationConstraint
{
TypeId generalizedType;
TypeId sourceType;
};
// subType ~ inst superType
struct InstantiationConstraint
{
TypeId subType;
TypeId superType;
};
struct UnaryConstraint
{
AstExprUnary::Op op;
TypeId operandType;
TypeId resultType;
};
// let L : leftType
// let R : rightType
// in
// L op R : resultType
struct BinaryConstraint
{
AstExprBinary::Op op;
TypeId leftType;
TypeId rightType;
TypeId resultType;
// When we dispatch this constraint, we update the key at this map to record
// the overload that we selected.
const AstNode* astFragment;
DenseHashMap<const AstNode*, TypeId>* astOriginalCallTypes;
DenseHashMap<const AstNode*, TypeId>* astOverloadResolvedTypes;
};
// iteratee is iterable
// iterators is the iteration types.
struct IterableConstraint
{
TypePackId iterator;
TypePackId variables;
};
// name(namedType) = name
struct NameConstraint
{
TypeId namedType;
std::string name;
bool synthetic = false;
};
// target ~ inst target
struct TypeAliasExpansionConstraint
{
// Must be a PendingExpansionType.
TypeId target;
};
struct FunctionCallConstraint
{
std::vector<NotNull<const struct Constraint>> innerConstraints;
TypeId fn;
TypePackId argsPack;
TypePackId result;
class AstExprCall* callSite;
std::vector<std::optional<TypeId>> discriminantTypes;
};
// result ~ prim ExpectedType SomeSingletonType MultitonType
//
// If ExpectedType is potentially a singleton (an actual singleton or a union
// that contains a singleton), then result ~ SomeSingletonType
//
// else result ~ MultitonType
struct PrimitiveTypeConstraint
{
TypeId resultType;
TypeId expectedType;
TypeId singletonType;
TypeId multitonType;
};
// result ~ hasProp type "prop_name"
//
// If the subject is a table, bind the result to the named prop. If the table
// has an indexer, bind it to the index result type. If the subject is a union,
// bind the result to the union of its constituents' properties.
//
// It would be nice to get rid of this constraint and someday replace it with
//
// T <: {p: X}
//
// Where {} describes an inexact shape type.
struct HasPropConstraint
{
TypeId resultType;
TypeId subjectType;
std::string prop;
};
// result ~ setProp subjectType ["prop", "prop2", ...] propType
//
// If the subject is a table or table-like thing that already has the named
// property chain, we unify propType with that existing property type.
//
// If the subject is a free table, we augment it in place.
//
// If the subject is an unsealed table, result is an augmented table that
// includes that new prop.
struct SetPropConstraint
{
TypeId resultType;
TypeId subjectType;
std::vector<std::string> path;
TypeId propType;
};
// if negation:
// result ~ if isSingleton D then ~D else unknown where D = discriminantType
// if not negation:
// result ~ if isSingleton D then D else unknown where D = discriminantType
struct SingletonOrTopTypeConstraint
{
TypeId resultType;
TypeId discriminantType;
bool negated;
};
using ConstraintV = Variant<SubtypeConstraint, PackSubtypeConstraint, GeneralizationConstraint, InstantiationConstraint, UnaryConstraint,
BinaryConstraint, IterableConstraint, NameConstraint, TypeAliasExpansionConstraint, FunctionCallConstraint, PrimitiveTypeConstraint,
HasPropConstraint, SetPropConstraint, SingletonOrTopTypeConstraint>;
struct Constraint
{
Constraint(NotNull<Scope> scope, const Location& location, ConstraintV&& c);
Constraint(const Constraint&) = delete;
Constraint& operator=(const Constraint&) = delete;
NotNull<Scope> scope;
Location location;
ConstraintV c;
std::vector<NotNull<Constraint>> dependencies;
};
using ConstraintPtr = std::unique_ptr<Constraint>;
inline Constraint& asMutable(const Constraint& c)
{
return const_cast<Constraint&>(c);
}
template<typename T>
T* getMutable(Constraint& c)
{
return ::Luau::get_if<T>(&c.c);
}
template<typename T>
const T* get(const Constraint& c)
{
return getMutable<T>(asMutable(c));
}
} // namespace Luau