luau/Analysis/include/Luau/ConstraintGraphBuilder.h
2022-06-23 18:56:00 -07:00

150 lines
5.5 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 <memory>
#include <vector>
#include <unordered_map>
#include "Luau/Ast.h"
#include "Luau/Constraint.h"
#include "Luau/Module.h"
#include "Luau/NotNull.h"
#include "Luau/Symbol.h"
#include "Luau/TypeVar.h"
#include "Luau/Variant.h"
namespace Luau
{
struct Scope2;
struct ConstraintGraphBuilder
{
// A list of all the scopes in the module. This vector holds ownership of the
// scope pointers; the scopes themselves borrow pointers to other scopes to
// define the scope hierarchy.
std::vector<std::pair<Location, std::unique_ptr<Scope2>>> scopes;
SingletonTypes& singletonTypes;
TypeArena* const arena;
// The root scope of the module we're generating constraints for.
Scope2* rootScope;
// A mapping of AST node to TypeId.
DenseHashMap<const AstExpr*, TypeId> astTypes{nullptr};
// A mapping of AST node to TypePackId.
DenseHashMap<const AstExpr*, TypePackId> astTypePacks{nullptr};
DenseHashMap<const AstExpr*, TypeId> astOriginalCallTypes{nullptr};
// Types resolved from type annotations. Analogous to astTypes.
DenseHashMap<const AstType*, TypeId> astResolvedTypes{nullptr};
// Type packs resolved from type annotations. Analogous to astTypePacks.
DenseHashMap<const AstTypePack*, TypePackId> astResolvedTypePacks{nullptr};
explicit ConstraintGraphBuilder(TypeArena* arena);
/**
* Fabricates a new free type belonging to a given scope.
* @param scope the scope the free type belongs to. Must not be null.
*/
TypeId freshType(Scope2* scope);
/**
* Fabricates a new free type pack belonging to a given scope.
* @param scope the scope the free type pack belongs to. Must not be null.
*/
TypePackId freshTypePack(Scope2* scope);
/**
* Fabricates a scope that is a child of another scope.
* @param location the lexical extent of the scope in the source code.
* @param parent the parent scope of the new scope. Must not be null.
*/
Scope2* childScope(Location location, Scope2* parent);
/**
* Adds a new constraint with no dependencies to a given scope.
* @param scope the scope to add the constraint to. Must not be null.
* @param cv the constraint variant to add.
*/
void addConstraint(Scope2* scope, ConstraintV cv);
/**
* Adds a constraint to a given scope.
* @param scope the scope to add the constraint to. Must not be null.
* @param c the constraint to add.
*/
void addConstraint(Scope2* scope, std::unique_ptr<Constraint> c);
/**
* The entry point to the ConstraintGraphBuilder. This will construct a set
* of scopes, constraints, and free types that can be solved later.
* @param block the root block to generate constraints for.
*/
void visit(AstStatBlock* block);
void visit(Scope2* scope, AstStat* stat);
void visit(Scope2* scope, AstStatBlock* block);
void visit(Scope2* scope, AstStatLocal* local);
void visit(Scope2* scope, AstStatLocalFunction* function);
void visit(Scope2* scope, AstStatFunction* function);
void visit(Scope2* scope, AstStatReturn* ret);
void visit(Scope2* scope, AstStatAssign* assign);
void visit(Scope2* scope, AstStatIf* ifStatement);
void visit(Scope2* scope, AstStatTypeAlias* alias);
TypePackId checkExprList(Scope2* scope, const AstArray<AstExpr*>& exprs);
TypePackId checkPack(Scope2* scope, AstArray<AstExpr*> exprs);
TypePackId checkPack(Scope2* scope, AstExpr* expr);
/**
* Checks an expression that is expected to evaluate to one type.
* @param scope the scope the expression is contained within.
* @param expr the expression to check.
* @return the type of the expression.
*/
TypeId check(Scope2* scope, AstExpr* expr);
TypeId checkExprTable(Scope2* scope, AstExprTable* expr);
TypeId check(Scope2* scope, AstExprIndexName* indexName);
std::pair<TypeId, Scope2*> checkFunctionSignature(Scope2* parent, AstExprFunction* fn);
/**
* Checks the body of a function expression.
* @param scope the interior scope of the body of the function.
* @param fn the function expression to check.
*/
void checkFunctionBody(Scope2* scope, AstExprFunction* fn);
/**
* Resolves a type from its AST annotation.
* @param scope the scope that the type annotation appears within.
* @param ty the AST annotation to resolve.
* @return the type of the AST annotation.
**/
TypeId resolveType(Scope2* scope, AstType* ty);
/**
* Resolves a type pack from its AST annotation.
* @param scope the scope that the type annotation appears within.
* @param tp the AST annotation to resolve.
* @return the type pack of the AST annotation.
**/
TypePackId resolveTypePack(Scope2* scope, AstTypePack* tp);
TypePackId resolveTypePack(Scope2* scope, const AstTypeList& list);
};
/**
* Collects a vector of borrowed constraints from the scope and all its child
* scopes. It is important to only call this function when you're done adding
* constraints to the scope or its descendants, lest the borrowed pointers
* become invalid due to a container reallocation.
* @param rootScope the root scope of the scope graph to collect constraints
* from.
* @return a list of pointers to constraints contained within the scope graph.
* None of these pointers should be null.
*/
std::vector<NotNull<Constraint>> collectConstraints(Scope2* rootScope);
} // namespace Luau