0.640

What's Changed

• Fixed many of the false positive errors in indexing of table unions and table intersections
• It is now possible to run custom checks over Luau AST during typechecking by setting customModuleCheck in FrontendOptions
• Fixed codegen issue on arm, where number->vector cast could corrupt that number value for the next time it's read

New Solver

• error type now behaves as the bottom type during subtyping checks
• Fixed the scope that is used in subtyping with generic types
• Fixed astOriginalCallTypes table often used by LSP to match the old solver

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Internal Contributors

Co-authored-by: Aaron Weiss [email protected]
Co-authored-by: Andy Friesen [email protected]
Co-authored-by: Vighnesh Vijay [email protected]
Co-authored-by: Vyacheslav Egorov [email protected]

Full Changelog: 0.639...0.640

0.639

What's Changed

• Fix size of userdata metatable array by @petrihakkinen in #1366
• Make os.clock use clock_gettime on FreeBSD by @Ketasaja in #1364
• Variety of bugfixes in the new solver
• Fix a bug in lua_resume where too many values might be removed from stack when resume throws an error

New Solver

• Fix an issue where we would hit a recursion limit when applying long chains of type refinements.
• Weaken the types of table.freeze and table.clone in the new solver so we can accept common code patterns like local a = table.freeze({x=5, x=0}) at the expense of accepting code like table.freeze(true).
• Don't warn when the # operator is used on a value of type never

Full Changelog: 0.638...0.639

Internal Contributors

Co-authored-by: Aaron Weiss [email protected]
Co-authored-by: Andy Friesen [email protected]
Co-authored-by: Vighnesh Vijay [email protected]
Co-authored-by: Vyacheslav Egorov [email protected]

0.638

What's Changed

New Solver

• Fix some type inference issues surrounding updates to upvalues eg

local x = 0

function f()
    x = x + 1
end

• User-defined type function progress
• Bugfixes for normalization of negated class types. eg SomeClass & (class & ~SomeClass)
• Fixes to subtyping between tables and the top table type.

Internal Contributors

Co-authored-by: Andy Friesen [email protected]
Co-authored-by: Jeremy Yoo [email protected]
Co-authored-by: Vyacheslav Egorov [email protected]

Full Changelog: 0.637...0.638

0.637

What's Changed?

• Bug fixes fixes in the new solver

New Solver

• Simplification of two completely disjoint tables combines them into a single table that inherits all properties / indexers
• Refining a never & <anything> does not produce type family types nor constraints
• Silence "inference failed to complete" error when it is the only error reported

---

Internal Contributors

Co-authored-by: Aaron Weiss [email protected]
Co-authored-by: Andy Friesen [email protected]
Co-authored-by: Dibri Nsofor [email protected]
Co-authored-by: Jeremy Yoo [email protected]
Co-authored-by: Vighnesh Vijay [email protected]
Co-authored-by: Vyacheslav Egorov [email protected]

New Contributors

• @ds-sloth made their first contribution in #1347

Full Changelog: 0.636...0.637

0.636

What's Changed?

• Telemetry support for usage of any type in old/new solver
• Bug fixes in the new solver

New Solver

• Fixed constraint ordering bug to infer types more accurately
• Improved inferring a call to setmetatable()

VM

• Restored global metatable lookup for typeof on lightuserdata to fix
  unintentional API change (Fixes #1335)

---

Internal Contributors

Co-authored-by: Aaron Weiss [email protected]
Co-authored-by: Alexander McCord [email protected]
Co-authored-by: Andy Friesen [email protected]
Co-authored-by: Dibri Nsofor [email protected]
Co-authored-by: Jeremy Yoo [email protected]
Co-authored-by: Vighnesh Vijay [email protected]
Co-authored-by: Vyacheslav Egorov [email protected]

New Contributors

• @kalrnlo made their first contribution in #1330

Full Changelog: 0.635...0.636

0.635

What's Changed?

• Bugfixes in the new solver
• Store definitionLocation in ClassType by @JohnnyMorganz in #1313
• Optimizations for UnionFind by @birds3345 in #1334

New Solver

• Equality graphs(E-Graphs) data structures were added
• Refactored even more instances of "type family" with "type function"
• table.insert no longer spuriously warns while selecting an overload for reasonable arguments.
• Add time tracing for the new solver
• Miscellaneous fixes to unit tests

---

Internal Contributors

Co-authored-by: Aaron Weiss [email protected]
Co-authored-by: Alexander McCord [email protected]
Co-authored-by: Jeremy Yoo [email protected]
Co-authored-by: Vighnesh Vijay [email protected]
Co-authored-by: Vyacheslav Egorov [email protected]

---

Full Changelog: 0.634...0.635

0.634

What's Changed?

• Performance improvement in the old solver
• Bugfixes in the new solver
• Keep commentLocations on SourceModule for definition files by @JohnnyMorganz in #1314
• Fix incorrect comment in Bytecode.h by @mttsner in #1315

Old Solver

• Mark types that do not need instantiation when being exported to
  prevent unnecessary work from being done

New Solver

• Index-out-of-bounds bug fix in the resolution resolver
• Subtyping reasonings are merged only if all failed

---

Internal Contributors

Co-authored-by: Aaron Weiss [email protected]
Co-authored-by: Vighnesh Vijay [email protected]
Co-authored-by: Vyacheslav Egorov [email protected]

New Contributors

• @mttsner made their first contribution in #1315

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Full Changelog: 0.633...0.634

0.633

What's Changed?

• Mostly stability and bugfixes with the new solver.

New Solver

• Typechecking with the new solver should respect the no-check hot comment.
• Record type alias locations and property locations of table assignments
• Maintain location information for exported table types
• Stability fixes for normalization
• Report internal constraint solver errors.

---

Internal Contributors

Co-authored-by: Aaron Weiss [email protected]
Co-authored-by: Alexander McCord [email protected]
Co-authored-by: Andy Friesen [email protected]
Co-authored-by: Vighnesh Vijay [email protected]
Co-authored-by: Vyacheslav Egorov [email protected]

---

Full Changelog: 0.632...0.633

0.632

What's Changed?

• Fix #1137 by appropriately retaining additional metadata from definition files throughout the type system.
• Improve Frontend for LSPs by appropriately allowing the cancellation of typechecking while running its destructor.

New Solver

• Added support for the rawget type function.
• Reduced overall static memory usage of builtin type functions.
• Fixed a crash where visitors could mutate a union or intersection type and fail to invalidate iteration over them in doing so.
• Revised autocomplete functionality to not rely on a separate run of the type solver when using the new solver.
• Implemented a more relaxed semantic rule for casting.
• Fixed some smaller crashes in the new solver.

Native Code Generation

• Add additional codegen specialization for math.sign
• Cleaned up a large number of outstanding fflags in the code.

Internal Contributors

Co-authored-by: Aaron Weiss [email protected]
Co-authored-by: Alexander McCord [email protected]
Co-authored-by: Andy Friesen [email protected]
Co-authored-by: James McNellis [email protected]
Co-authored-by: Jeremy Yoo [email protected]
Co-authored-by: Vighnesh Vijay [email protected]
Co-authored-by: Vyacheslav Egorov [email protected]

---

Full Changelog: 0.631...0.632

0.631

What's new

• Added lint warning for using redundant @native attributes on functions inside a --!native module
• Improved typechecking speed in old solver for modules with large types

New Solver

• Fixed the length type function sealing the table prematurely
• Fixed crashes caused by general table indexing expressions

VM

• Added support for a specialized 3-argument fast-call instruction to improve performance of vector constructor, buffer writes and a few bit32 methods

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Full Changelog: 0.630...0.631