3.6.1

This is a fast-track release to replace a broken release 3.6.0 that occurred during the Scala 3.6.0-RC1 release. It might contain bugs that would be have been fixed during the Release Candidate bugfixes period. We recommend waiting for the stable Scala 3.6.2 release.

Scala 3.6.0 should never be used to produce libraries. TASTy files produced by this version of the compiler are produced in the experimental mode. These outputs are not compatible with consumers using stable versions of the compiler.

See details in Scala 3.6.0 Post Mortem blogpost

Highlights of the release

• Stabilise SIP-47 (Adding Clause Interleaving to method definitions) #20861
• Implement SIP-57 - add runtimeChecked method and annotation #20987
• Implement SIP-62 - For comprehension improvements #20522
• Implement SIP-64 as non-experimental #21668
• Make named tuples a standard feature #21680
• Switch mapping of context bounds to using clauses in 3.6 #21257
• Require named arguments for java defined annotations #21329

Other changes and fixes

Annotations

• Tighten java annot value parsing #21650

Dependencies

• REPL: JLine 3.27.0 (was 3.25.1) #21752
• Scala 2.13.15 (was .14) #21648

Erasure

• Fixes IllegalAccessError with Java package protected class #21362

Experimental: Capture Checking

• Existential Capabilities #20566
• Fix setup of CapSet arguments. #21309
• Check all top-level covariant capture sets in checkNotUniversal #21428
• Charge also dcs of local reaches to capture set of enclosing method #21443
• No need to unbox if expected type is LhsProto #21508
• Treat more closure parameter types as inferred #21583
• Fixes for cleanup retains scheme #21350
• Improve Contains handling #21361
• Expand Capability types T to T^ only if no explicit capture set is given #21375
• Tighten closure extractor in TreeInfo #21621

Experimental: Strict Equality

• Fix #21392: Adjust canComparePredefined(Nothing, T) in explicit nulls #21504
• Add tracking of NotNullInfo for Match, Case, Try trees (fix #21380) #21389

Experimental: Modularity

• Revised given syntax #21208

Experimental: Global Initialization

• Analyze object when selecting from package #21511
• Fix bug in init checker while compiling scodec-bits community project #21574

Experimentals

• [experimental feature] Support HOAS pattern with type variables for quote pattern matching #18271

Exports

• Re-use attachment in exportForwarders to handle ambiguous overloads #21518
• Allow export statements in AnyVal #21653

Extension Methods

• Make right assoc ext method fwd refs error #21641

Inline

• Fix: throw an error before assigning ErrorType when expanding constValue #21364

Implicits

• Fix prioritization of givens over implicits #21226

JVM backend

• Backend computes line number from source of position #21763

Linting

• CheckUnused checks type param annotations #20549

Library

• Finalize named tuples #21710

Match Types

• Enable betterMatchTypeExtractors in >= 3.6 #21198
• Do not propagate TypeErrors of ops from TypeComparer#tryAlso #21070
• Fix #21402: Always allow type member extraction for stable scrutinees in match types. #21700
• Add a 3.6-migration warning for MT lubbing #21336
• Always interpret underscores inside patterns as type bounds #21718

Opaque Types

• Capture the kse3 issue in test cases and close it #21260

Parser

• Guard against recursive lower bounds in constraints #21587

Pattern Matching

• Fix a bundle of patmat issues #21000

Pickling

• Some fixes for AnnotatedTypes mapping #19957

Polyfunctions

• Fix: Check if a PolyFunction TypeTree has no ByName parameters #21671

Presentation Compiler

• Add regression test for issue 18726 #20318
• Remove artificial CURSOR added to code in the completions #20899
• Fix autoimports with using directives #21590

Quotes

• Handle suspension due to macro call in arbitrary phases #21651
• Have a better error message when healing types #21711
• Bound TypeRepr by Matchable in Quotes #21377
• Expr#show: Don't crash when the expression contains an unsupported type (like a SkolemType) #20494

Reflection

• Add the possibility to create a typeSymbol in the Quotes API #20347
• Fix stale symbols connected to lazy vals in macros #21559

Reporting

• Add better error reporting for inlined non-immutable paths #21639
• Only replace new errors by warnings under -migration #21289

REPL

• Ignore best effort settings in repl and update docs #21540

Rewrites

• Remove empty argument lists for classes with only context bounds #21513
• Fix rewrite logic for old <function> _ syntax #21715
• Remove the -rewrite option for typechecks methods in Quotes #21547
• Add migration rewrite for non-named arguments in Java annotations #21397

Scaladoc

• Only trim one newline when preprocessing the content of a markdown code snippet #21519
• Filter opaque modifier from object documentation #21640
• Bump Inkuire version to fix it for the new Scala versions #21611

Standard Library

• Move NamedTuple.head to NamedTupleDecomposition #21308
• Define binary symbolic compiletime ops as infix #21683

Transform

• Fix treatment of separately compiled @Native methods in FirstTransform #21593
• Three fixes to SAM type handling #21596
• Always rewrite empty List() to Nil #21689
• Add support for clauseInterleaving in JVM generic signatures #21709

Typeclass Derivation

• Nicer error message in case a derived method has an explicit term param #21332

Typer

• Calm param autotupling for overloads #21552
• Survive inaccessible types when computing implicit scope #21589
• Avoid cyclic errors forcing default arg types #21597
• Fix incorrect caching with dependent method parameters #21699

Contributors

Thank you to all the contributors who made this release possible 🎉

According to git shortlog -sn --no-merges 3.5.2..3.6.1 these are:

   129  Martin Odersky
    35  Hamza REMMAL
    34  Dale Wijnand
    31  Eugene Flesselle
    31  Hamza Remmal
    30  Wojciech Mazur
    15  Kacper Korban
    12  Jamie Thompson
    11  Jan Chyb
    11  Katarzyna Marek
     9  noti0na1
     9  rochala
     8  Adrien Piquerez
     8  Matt Bovel
     7  Som Snytt
     7  dependabot[bot]
     6  Yichen Xu
     5  EnzeXing
     5  Fengyun Liu
     5  Guillaume Martres
     5  Sébastien Doeraene
     4  Tomasz Godzik
     4  kasiaMarek
     3  Martin Duhem
     3  Oliver Bracevac
     3  Piotr Chabelski
     2  Aleksander Rainko
     2  David Hua
     2  Florian3k
     2  Friendseeker
     2  HarrisL2
     2  Joel Wilsson
     2  Jędrzej Rochala
     2  Kenji Yoshida
     2  Seth Tisue
     1  Eugene Yokota
     1  Georgi Krastev
     1  Kavin Satheeskumar
     1  Lorenzo Gabriele
     1  Michał Pałka
     1  Michel Charpentier
     1  Ondrej Lhotak
     1  Raphael Jolly
     1  Yuito Murase
     1  crunchyfrog
     1  friendseeker
     1  philippus