0.562

Language Changes

A new language feature - string interpolation, is now stable and available for use in default configuration.
Read more about it in the announcement.

Analysis Changes

• Fixed rare use-after-free in analysis during table unification

For extra notes about internal development, you can read #828

0.561

What's Changed

• Fix a potential debugger crash by adding checks for invalid stack index values

0.560

Autocomplete Changes

• Additional information is included in Scope for type alias name locations and names of imported modules
• Improved suggestions in 'for' and 'while' loop headers

Analysis Changes

• String match functions return types are now optional strings and numbers because match is not guaranteed at runtime

Runtime Changes

• Fix lua_*upvalue() when upvalue names aren't in debug info by @HaroldCindy in #787

Other Changes

• Fixed build issue on gcc 11 and up (Fixes #806)

0.559

Autocomplete Changes

• Fix autocompletion of if-then-else expressions
• Pass string content to autocomplete callback by @JohnnyMorganz in #800
• Attach definition location to TableType by @JohnnyMorganz in #801

Runtime Changes

• Fix a potential crash surrounding improper use of %* in a string format specifier
• Improved error handling for string interpolation with too many arguments

Other Changes

• All Python scripts now invoke Python via python3 rather than python

0.558

Analysis changes

• Fixed garbage data in module scopes when type graph is not retained

Runtime changes

• LOP_MOVE with the same source and target registers is no longer
  generated (Fixes #793)

0.557

Analysis changes

• Fixed unions of nil types displaying as ?
• Internal normalization now handles class types which can make previously failing (incorrectly) sub-typing checks to succeed

0.556

What's Changed

• The AST JSON encoder will now stringify infinity and NaN according to the JSON5 spec using the tokens Infinity, -Infinity, and NaN.
• Improve autocompletion of table keys if the type of that key is a union of string singletons.

0.555

Analysis changes

• Type mismatch errors now mention if unification failed in covariant or invariant context, to explain why sometimes derived class can't be converted to base class or why T can't be converted into T? and so on
• Class type indexing is no longer an error in non-strict mode (still an error in strict mode)
• Fixed cyclic type packs not being displayed in the type
• Added an error when unrelated types are compared with ==/~=
• Fixed false positive errors involving sub-type tests with a never type

Runtime changes

• Fixed miscompilation of multiple assignment statements (Fixes #754)

Community contributions

• Handle cyclically referenced declared classes by @JohnnyMorganz in #729
• Support __call on class type vars by @JohnnyMorganz in #762

0.554

What's Changed

• Fix string interpolation autocomplete and location by @Kampfkarren in #748

Full Changelog: 0.553...0.554

0.553

Analysis Changes

• Type inference of a and b and a or b has been improved (Fixes #730)
• Improved error message when for ... in x loop iterates over a value that could be 'nil'
• Return type of next not includes 'nil' (Fixes #706)
• Improved type inference of string type
• Luau library table type names are now reported as typeof(string)/etc instead of just string which was misleading
• Added parsing error when optional type alias type parameter wasn't provided after = token
• Improved tagged union type refinement in conditional expressions, type in else branch should no longer include previously handled union options