Sync to upstream/release/667

Analysis/include/Luau/Constraint.h

@@ -50,6 +50,7 @@ struct GeneralizationConstraint
     TypeId sourceType;
 
     std::vector<TypeId> interiorTypes;
+    bool hasDeprecatedAttribute = false;
 };
 
 // variables ~ iterate iterator

Analysis/include/Luau/ConstraintSolver.h

@@ -365,7 +365,7 @@ struct ConstraintSolver
      * @returns a non-free type that generalizes the argument, or `std::nullopt` if one
      * does not exist
      */
-    std::optional<TypeId> generalizeFreeType(NotNull<Scope> scope, TypeId type, bool avoidSealingTables = false);
+    std::optional<TypeId> generalizeFreeType(NotNull<Scope> scope, TypeId type);
 
     /**
      * Checks the existing set of constraints to see if there exist any that contain

Analysis/include/Luau/DataFlowGraph.h

@@ -38,8 +38,6 @@ struct DataFlowGraph
     DefId getDef(const AstExpr* expr) const;
     // Look up the definition optionally, knowing it may not be present.
     std::optional<DefId> getDefOptional(const AstExpr* expr) const;
-    // Look up for the rvalue def for a compound assignment.
-    std::optional<DefId> getRValueDefForCompoundAssign(const AstExpr* expr) const;
 
     DefId getDef(const AstLocal* local) const;
 
@@ -66,10 +64,6 @@ struct DataFlowGraph
     // All keys in this maps are really only statements that ambiently declares a symbol.
     DenseHashMap<const AstStat*, const Def*> declaredDefs{nullptr};
 
-    // Compound assignments are in a weird situation where the local being assigned to is also being used at its
-    // previous type implicitly in an rvalue position. This map provides the previous binding.
-    DenseHashMap<const AstExpr*, const Def*> compoundAssignDefs{nullptr};
-
     DenseHashMap<const AstExpr*, const RefinementKey*> astRefinementKeys{nullptr};
     friend struct DataFlowGraphBuilder;
 };

Analysis/include/Luau/FragmentAutocomplete.h

@@ -49,6 +49,8 @@ struct FragmentAutocompleteAncestryResult
     std::vector<AstLocal*> localStack;
     std::vector<AstNode*> ancestry;
     AstStat* nearestStatement = nullptr;
+    AstStatBlock* parentBlock = nullptr;
+    Location fragmentSelectionRegion;
 };
 
 struct FragmentParseResult
@@ -59,6 +61,7 @@ struct FragmentParseResult
     AstStat* nearestStatement = nullptr;
     std::vector<Comment> commentLocations;
     std::unique_ptr<Allocator> alloc = std::make_unique<Allocator>();
+    Position scopePos{0, 0};
 };
 
 struct FragmentTypeCheckResult
@@ -76,23 +79,42 @@ struct FragmentAutocompleteResult
     AutocompleteResult acResults;
 };
 
-FragmentAutocompleteAncestryResult findAncestryForFragmentParse(AstStatBlock* root, const Position& cursorPos);
+struct FragmentRegion
+{
+    Location fragmentLocation;
+    AstStat* nearestStatement = nullptr; // used for tests
+    AstStatBlock* parentBlock = nullptr; // used for scope detection
+};
 
-std::optional<FragmentParseResult> parseFragment(
+FragmentRegion getFragmentRegion(AstStatBlock* root, const Position& cursorPosition);
+FragmentAutocompleteAncestryResult findAncestryForFragmentParse(AstStatBlock* stale, const Position& cursorPos, AstStatBlock* lastGoodParse);
+FragmentAutocompleteAncestryResult findAncestryForFragmentParse_DEPRECATED(AstStatBlock* root, const Position& cursorPos);
+
+std::optional<FragmentParseResult> parseFragment_DEPRECATED(
     AstStatBlock* root,
     AstNameTable* names,
     std::string_view src,
     const Position& cursorPos,
     std::optional<Position> fragmentEndPosition
 );
 
+std::optional<FragmentParseResult> parseFragment(
+    AstStatBlock* stale,
+    AstStatBlock* mostRecentParse,
+    AstNameTable* names,
+    std::string_view src,
+    const Position& cursorPos,
+    std::optional<Position> fragmentEndPosition
+);
+
 std::pair<FragmentTypeCheckStatus, FragmentTypeCheckResult> typecheckFragment(
     Frontend& frontend,
     const ModuleName& moduleName,
     const Position& cursorPos,
     std::optional<FrontendOptions> opts,
     std::string_view src,
     std::optional<Position> fragmentEndPosition,
+    AstStatBlock* recentParse = nullptr,
     IFragmentAutocompleteReporter* reporter = nullptr
 );
 
@@ -104,6 +126,7 @@ FragmentAutocompleteResult fragmentAutocomplete(
     std::optional<FrontendOptions> opts,
     StringCompletionCallback callback,
     std::optional<Position> fragmentEndPosition = std::nullopt,
+    AstStatBlock* recentParse = nullptr,
     IFragmentAutocompleteReporter* reporter = nullptr
 );
 

Analysis/include/Luau/Frontend.h

@@ -10,7 +10,6 @@
 #include "Luau/Set.h"
 #include "Luau/TypeCheckLimits.h"
 #include "Luau/Variant.h"
-#include "Luau/AnyTypeSummary.h"
 
 #include <mutex>
 #include <string>
@@ -34,7 +33,6 @@ struct HotComment;
 struct BuildQueueItem;
 struct BuildQueueWorkState;
 struct FrontendCancellationToken;
-struct AnyTypeSummary;
 
 struct LoadDefinitionFileResult
 {

Analysis/include/Luau/Generalization.h

@@ -13,8 +13,7 @@ std::optional<TypeId> generalize(
     NotNull<BuiltinTypes> builtinTypes,
     NotNull<Scope> scope,
     NotNull<DenseHashSet<TypeId>> cachedTypes,
-    TypeId ty,
-    /* avoid sealing tables*/ bool avoidSealingTables = false
+    TypeId ty
 );
 
 }

Analysis/include/Luau/Module.h

@@ -8,7 +8,6 @@
 #include "Luau/ParseResult.h"
 #include "Luau/Scope.h"
 #include "Luau/TypeArena.h"
-#include "Luau/AnyTypeSummary.h"
 #include "Luau/DataFlowGraph.h"
 
 #include <memory>
@@ -21,14 +20,13 @@ LUAU_FASTFLAG(LuauIncrementalAutocompleteCommentDetection)
 namespace Luau
 {
 
-using LogLuauProc = void (*)(std::string_view);
+using LogLuauProc = void (*)(std::string_view, std::string_view);
 extern LogLuauProc logLuau;
 
 void setLogLuau(LogLuauProc ll);
 void resetLogLuauProc();
 
 struct Module;
-struct AnyTypeSummary;
 
 using ScopePtr = std::shared_ptr<struct Scope>;
 using ModulePtr = std::shared_ptr<Module>;
@@ -86,10 +84,6 @@ struct Module
     TypeArena interfaceTypes;
     TypeArena internalTypes;
 
-    // Summary of Ast Nodes that either contain
-    // user annotated anys or typechecker inferred anys
-    AnyTypeSummary ats{};
-
     // Scopes and AST types refer to parse data, so we need to keep that alive
     std::shared_ptr<Allocator> allocator;
     std::shared_ptr<AstNameTable> names;

Analysis/include/Luau/NonStrictTypeChecker.h

@@ -1,9 +1,10 @@
 // This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
 #pragma once
 
+#include "Luau/DataFlowGraph.h"
+#include "Luau/EqSatSimplification.h"
 #include "Luau/Module.h"
 #include "Luau/NotNull.h"
-#include "Luau/DataFlowGraph.h"
 
 namespace Luau
 {

Analysis/include/Luau/Type.h

@@ -19,7 +19,6 @@
 #include <optional>
 #include <set>
 #include <string>
-#include <unordered_map>
 #include <vector>
 
 LUAU_FASTINT(LuauTableTypeMaximumStringifierLength)
@@ -38,6 +37,15 @@ struct Constraint;
 struct Subtyping;
 struct TypeChecker2;
 
+enum struct Polarity : uint8_t
+{
+    None = 0b000,
+    Positive = 0b001,
+    Negative = 0b010,
+    Mixed = 0b011,
+    Unknown = 0b100,
+};
+
 /**
  * There are three kinds of type variables:
  * - `Free` variables are metavariables, which stand for unconstrained types.
@@ -396,6 +404,7 @@ struct FunctionType
     // this flag is used as an optimization to exit early from procedures that manipulate free or generic types.
     bool hasNoFreeOrGenericTypes = false;
     bool isCheckedFunction = false;
+    bool isDeprecatedFunction = false;
 };
 
 enum class TableState

Analysis/include/Luau/TypeFunction.h

@@ -177,6 +177,7 @@ struct FunctionGraphReductionResult
     DenseHashSet<TypePackId> blockedPacks{nullptr};
     DenseHashSet<TypeId> reducedTypes{nullptr};
     DenseHashSet<TypePackId> reducedPacks{nullptr};
+    DenseHashSet<TypeId> irreducibleTypes{nullptr};
 };
 
 /**