3.8.4-RC1

Highlights of the release

• Bump Scala CLI to 1.12.5 and Coursier to 2.1.25-M24 #25592

Other changes and fixes

Annotations

• Also copy param annots at mixin #24916
• Named arg may be deprecatedName #21588
• Use dealiasKeepRefiningAnnots in AvoidMap #25609

Backend

• Do not simplify isInstanceOf if unrelated types might be subtypes at run-time #25535
• Port more Scala2 tests + some mixin improvements #25573
• Use Objects.equals in translating == #25314

Compiler Phases

• Harden Period creation and use of Run/PhaseId #25484
• Make Phase.run protected #25366

Context Functions

• Fix crash when processing path dependent context functions using HKTs #25530

Coverage

• Fix #25555: Preserve singleton precision during scoverage lifting #25556
• Fixes #25482: Ensure package transformation properly handles language imports in InstrumentCoverage #25546
• Scoverage: do not instrument erased values. #25298

Default parameters

• Fix named arguments evaluation order with by-name parameters #25161
• Typer: remove by-name lifting and replace default-getter args with fresh syms #25502

Documentation

• Error mentions bad _1 selector #25616
• Document Scala compiler error codes #24734
• Fix capture checking doc links in language.scala #25498
• Docs: apply snippet compiler on new types reference docs #19513
• Remove outdated comment in value classes #25428
• Update IsIterable scaladoc #24692

Enums

• Make enum apply ascriptions inferred types #25562

Experimental: Capture Checking

• Distribute capture set into and-type on RHS of comparison #25509
• Fix global capabilities support in scaladoc #25563
• Improve capture-error precision for lambdas #25583
• Make result types of hoisted superArg defs InferredTypes #25577
• Transform result any to fresh in Setup.transformSym #25584
• Propagate expected types when rechecking match return expressions #25580
• Drop assertion in toFunctionType #25628
• Delay normalization of capture sets of vals and defs #25640
• Fluidify explicit self types for non-CC classes #25639
• Add missing TypeMap in Setup: FreshCapToResult #25648
• Fixes for capture checking case class methods #25278
• Don't add capture variables for type arguments with pure upper bounds #25316
• Two fixes for #25251 #25488
• Fixed #25430: Add missing CaptureChecked flag during ExpandSAMs #25443
• Fix accessibility check for any's in static objects #25582
• Disallow type parameters in OnlyCapability annotations #25496
• Capture check Try #25072
• Make Capability types have implied capture sets for new #25346

Experimental: Safe Mode

• Enhance safe mode #25638
• Fixes to Safe Mode Checking #25603

Extension Methods

• Accept using right associative parameters #24766
• Better handling of illegal trees in extension #25368

GADTs

• Also trust TypeTest when there is a Bind #24568

Implicits

• Deprecation when inferring implicit from non-accessible companion #25516
• Fix missing deprecation warning for implicit in non-accessible companion #25608
• Update migration message #25627

Inline

• Enhance constant-folding during inlining #24431
• Ensure the inline match scrutinee type conforms to the recalculated type #24988
• Do not update Symbol defTrees when retyping after Inlining #23870
• Inlines: decide sealing against original target, while using widened type as cast destination #25448
• Do not generate access proxies for locally defined protected defs #25056
• Avoid useless scrutinee proxy vals in inline match reduction #25279

Linting

• Match apply in PolyFunction for override #25505
• Value discard checks inline call for exemption #25554
• Introduce error message ids for shadow warnings #25101

Match Types

• Restore MatchTypeNoCases warning with correct source position #25470

Named Tuples

• Fix Ycheck crash from singleton tuple selects after specialization #25331
• Fix #23621: make named tuples exhaustive checkable #25267

Nullability

• Patch to allow interop with XMLBuilder and -Yexplicit-nulls #25221
• Be honest about the nullability of ConsoleReporter.reader and SourcePosition.outer. #25561

Opaque Types

• Treat synthetic casts as pure #25126

Overloading

• Pretype args before skipping clause of overloaded application #23012

Parser

• Fix #20063: Java leading annotation parsing #25503
• Observe outdent also for type cases and type blocks in quotes #25519
• Fix: import resolution for Java #25537
• Fix #25456: parser crash on polymorphic context bound #25623
• Accept primitive.class in annotations #25363
• InCase has indent width of case #25295
• Don't automatically insert OUTDENT before COMMA #25501
• Add "did you mean to use parentheses/a block" when finding a complex expression on the RHS of an infix operator #25099

Pattern Matching

• Clean desugaring of simple tuple assignments #25010
• Extend caching in the space engine beyond local context #23483
• Prevent from getting children in case of non-sealed private #25359
• Use MatchCaseUnreachable #24829
• Fix wrong exhaustive check with sequence wildcard on case class with custom unapply #24260
• Try expanding case class to the product of its fields #25454

Positions

• Preserve span of this during statification of trait constructors #25354

Presentation Compiler

• Improvement: Add fallbacks in non critical places for presentation compiler #25483
• Improvement: Use method type if it's available #25641
• Bugfix: Fix wrong type in InferredType code action #25469
• Fix & feat: improvements in selection ranges #25290
• Fix: ignore implicit apply for signature help #25294
• Bugfix: remove stale top-level symbols between runs #25317

Quotes

• Fix crashing for context bound type variables in quoted patterns #25286
• Remove redundant mapOver in fixThisTypeModuleClassReferences [#25440](#254...

3.8.3

Release highlights

• Add support for local coverage on and off with // $COVERAGE-OFF$ and // $COVERAGE-ON$ #24486
• Deprecate for removal -print-lines compiler setting #25330
• Add safe mode capture checking extension #25307
• Port the Scala2 JVM backend optimizer #25165

Other changes and fixes

Desugaring

• Fix #24997: Avoid unnecessary CHECKCAST in untupled function parameters #25085

Documentation

• Fix little errors in the API documentation #25241
• CC Language Reference: Rename cap to any/fresh #25057

Enums

• Deprecate override class, improve checks #24828
• Fix Java enum forwarders to pull from companion on initialization #24361

Experimental: Capture Checking

• Rename caps.cap to caps.any #24923
• Track global capabilities #24883
• Treat local mutable vars as capabilities #24815
• Fix Crashes when Capture-set Parameters Conflict with Terms #25029
• Replace "cannot be included in" by "cannot flow into" in error messages #25155
• CC: Add field captures to self-type constraints #24984
• Add uses clauses for templates #24857
• Drop special code paths for objects #24881
• Do not consider generated getters to be update def #24906
• Under cc, mark inferred type arguments to inline methods with an @inferred annotation #25175
• Handle call-by-name types in bad locations under cc #25154
• Fixes for global capabilities #25123
• Warn if reach capability in result will likely cause leakage #24860
• Make <fluid> decorations replace existing capture sets #25012
• Make TypeMaps in Setup work correctly for fresh #24985
• For a limited time, also recognize caps.cap #25076
• Fix closure typing #25014
• Map class capture sets via as-seen-from with prefix of created types #24830
• Drop SafeMode attribute in Tasty #25357
• Fix @assumeSafe addition in safe mode #25364
• Disallow @assumeSafe under safe mode #25462

Experimental: Modularity

• Fix nested desugaring of applied constructor types #25288

Exports

• Add ctor proxies before exports #24884

Inline

• Make containsOuterRefsAnywhere follow aliases #25214
• Find annotation args in inline expansion #24895
• Also substitute symbols in case bindings symbols #24849

JDK

• Skip over JEP 445 compact compilation units #23247
• Handle MissingType during Erasure phase #24817

JVM Backend

• Simplify JVM interface list emission, remove a mini-phase #25203
• Don't generate bridge methods for inaccessible Java package-private methods #25166
• Revise isLocalToCompilationUnit #24856
• Enforce JVM UTF-8 string limits in the backend #25300
• Fix class super-call invokespecial owner #25437

Linting

• Extension check handles hiBound of opaque type #25172
• Distrust tree pos for patvar lint #25043
• Move second CheckUnused after pattern matcher #25114
• Unused lint ignores args to ctor of enclosing class #24768
• Check inline expansion for exclusion #23019

Metaprogramming

• Fix: Fix incremental compilation of (some unquoted) macros #24969

Named Tuples

• Don't try checking for ambiguous single-element tuples when in types #24910
• Fix "NamedTuple type in match is parsed as named pattern" #24929
• Fix "Named pattern matching doesn't work in val statements or for generators" #24928
• Fix false exhaustivity warning for pattern returning NamedTuple #23362

Overloading

• Prefer non-extension to extension #24943

Parser

• Check seen for TypeParamRef in TypeSizeAccumulator #25264
• End of new expr never shrinks #25253
• Use toVector for XML literal sequences #23221

Pattern Matching

• Emit unchecked warnings for trait patterns #24962

Presentation Compiler

• Bugfix: inline value false-positive shadowing with lambda params #25140
• Test hover on backticked identifiers with whitespace #25142
• Inlining interpolated variables #25144
• Bugfix: treat self types as parent types #25167
• Feat(pc): add closing labels inlay hints #25178
• Coursier dependency imports should have lexicographic ordering #21592
• Bugfix: Fix various minor presentation compiler issues #25256
• Fix negative activeParameter in signature help #24945
• Closes #7532: Parameter hints not working for functions #23854
• Fix opaque types displayed as Nothing & Any in hover and signature help #24921

REPL

• Skip module-info.class files during REPL tab-completion #24838
• Fix REPL usage of macros loaded via :dep and :jar #25312
• Make REPL type echo-ing use partially qualified names where made possible by imports #24850
• Force REPL to not evaluate LazyList #25444

Reporting

• Check -Werror on summarize #25096
• Fixes #24233: Remove misleading JDK compatibility hint for TASTy errors #25171
• Ignore resetting if preferPrevious #24991
• Enhance WInferUnion to not warn propagated explicit union types #25280
• Improve diagnostic message for unnecessary trailing underscore in eta-expansion #25285
• More descriptive "not found" message when type/term exists with the expected term/type name #24959
• Warn on Scala 2 auto-apply if loosely nullary #24811
• Fix printing references to nested objects #25086
• Add error note for type mismatch involving blocks without last expression #25181
• Drop -print-lines option #24905
• Don't suggest invisible members of root imports #24999

Runner

• Bump Scala CLI to v1.12.3 (was v1.12.2) #25365
• Bump Scala CLI to 1.12.4 (was 1.12.3) #25434

Rewrites

• Accommodate ArrowAssoc in infix named arg migration #25255

Scaladoc

• Init MacroClassLoader in scaladoc #25141
• Scaladoc Overload Method Link Fix #25156
• Fix duplicate member entries in Scaladoc generation #24712
• Scaladoc Tests for CC #25277
• Skip generation of API pages when building reference docs #25153
• Docs: Enfo...

3.8.3-RC3

Backported chnages

• Fix issues with Scala JS and the presentation compiler #25550
• Enforce JVM UTF-8 string limits in the backend #25300
• Fix class super-call invokespecial owner #25437
• Port the Scala2 optimizer #25165

Contributors

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

According to git shortlog -sn --no-merges 3.8.3-RC2..3.8.3-RC3 these are:

    49  Solal Pirelli
     3  Wojciech Mazur
     1  Rikito Taniguchi
     1  Tomasz Godzik

3.8.3-RC2

Backported changes

• Bump Scala CLI to v1.12.3 (was v1.12.2) #25365
• Bump Scala CLI to 1.12.4 (was 1.12.3) #25434
• Fix Java enum forwarders to pull from companion on initialization #24361
• Fix issues in presentation compiler when using Scala JS #25450
• Add safe mode #25307
• Drop SafeMode attribute in Tasty #25357
• Fix @assumeSafe addition in safe mode #25364
• Disallow @assumeSafe under safe mode #25462
• Don't enable compact annotations under 2.13. #25419
• Don't absolutize sources outside of the sourceroot in TASTy #25429
• Docs: Enforce links checks in the generated docs #25425
• Preserve insertion order when balancing And/OrType #25361
• Improve ref check of constructors #24342
• Force REPL to not evaluate LazyList #25444
• Fix REPL usage of macros loaded via :dep and :jar #25312

Contributors

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

According to git shortlog -sn --no-merges 3.8.3-RC1..3.8.3-RC2 these are:

    16	Wojciech Mazur
    12	Martin Odersky
    10	Solal Pirelli
     2	Tomasz Godzik
     1	Piotr Chabelski
     1	Som Snytt

3.8.3-RC1

Release highlights

• Add support for local coverage on and off with // $COVERAGE-OFF$ and // $COVERAGE-ON$ #24486
• Deprecate for removal -print-lines compiler setting #25330

Other changes and fixes

Desugaring

• Fix #24997: Avoid unnecessary CHECKCAST in untupled function parameters #25085

Documentation

• Fix little errors in the API documentation #25241
• CC Language Reference: Rename cap to any/fresh #25057

Enums

• Deprecate override class, improve checks #24828
• Fix Java enum forwarders to pull from companion on initialization #24361

Experimental: Capture Checking

• Rename caps.cap to caps.any #24923
• Track global capabilities #24883
• Treat local mutable vars as capabilities #24815
• Fix Crashes when Capture-set Parameters Conflict with Terms #25029
• Replace "cannot be included in" by "cannot flow into" in error messages #25155
• CC: Add field captures to self-type constraints #24984
• Add uses clauses for templates #24857
• Drop special code paths for objects #24881
• Do not consider generated getters to be update def #24906
• Under cc, mark inferred type arguments to inline methods with an @inferred annotation #25175
• Handle call-by-name types in bad locations under cc #25154
• Fixes for global capabilities #25123
• Warn if reach capability in result will likely cause leakage #24860
• Make <fluid> decorations replace existing capture sets #25012
• Make TypeMaps in Setup work correctly for fresh #24985
• For a limited time, also recognize caps.cap #25076
• Fix closure typing #25014
• Map class capture sets via as-seen-from with prefix of created types #24830

Experimental: Modularity

• Fix nested desugaring of applied constructor types #25288

Exports

• Add ctor proxies before exports #24884

Inline

• Make containsOuterRefsAnywhere follow aliases #25214
• Find annotation args in inline expansion #24895
• Also substitute symbols in case bindings symbols #24849

JDK

• Skip over JEP 445 compact compilation units #23247
• Handle MissingType during Erasure phase #24817

JVM Backend

• Simplify JVM interface list emission, remove a mini-phase #25203
• Don't generate bridge methods for inaccessible Java package-private methods #25166
• Revise isLocalToCompilationUnit #24856

Linting

• Extension check handles hiBound of opaque type #25172
• Distrust tree pos for patvar lint #25043
• Move second CheckUnused after pattern matcher #25114
• Unused lint ignores args to ctor of enclosing class #24768
• Check inline expansion for exclusion #23019

Metaprogramming

• Fix: Fix incremental compilation of (some unquoted) macros #24969

Named Tuples

• Don't try checking for ambiguous single-element tuples when in types #24910
• Fix "NamedTuple type in match is parsed as named pattern" #24929
• Fix "Named pattern matching doesn't work in val statements or for generators" #24928
• Fix false exhaustivity warning for pattern returning NamedTuple #23362

Overloading

• Prefer non-extension to extension #24943

Parser

• Check seen for TypeParamRef in TypeSizeAccumulator #25264
• End of new expr never shrinks #25253
• Use toVector for XML literal sequences #23221

Pattern Matching

• Emit unchecked warnings for trait patterns #24962

Presentation Compiler

• Bugfix: inline value false-positive shadowing with lambda params #25140
• Test hover on backticked identifiers with whitespace #25142
• Inlining interpolated variables #25144
• Bugfix: treat self types as parent types #25167
• Feat(pc): add closing labels inlay hints #25178
• Coursier dependency imports should have lexicographic ordering #21592
• Bugfix: Fix various minor presentation compiler issues #25256
• Fix negative activeParameter in signature help #24945
• Closes #7532: Parameter hints not working for functions #23854
• Fix opaque types displayed as Nothing & Any in hover and signature help #24921

REPL

• Skip module-info.class files during REPL tab-completion #24838
• Fix REPL usage of macros loaded via :dep and :jar #25312
• Make REPL type echo-ing use partially qualified names where made possible by imports #24850

Reporting

• Check -Werror on summarize #25096
• Fixes #24233: Remove misleading JDK compatibility hint for TASTy errors #25171
• Ignore resetting if preferPrevious #24991
• Enhance WInferUnion to not warn propagated explicit union types #25280
• Improve diagnostic message for unnecessary trailing underscore in eta-expansion #25285
• More descriptive "not found" message when type/term exists with the expected term/type name #24959
• Warn on Scala 2 auto-apply if loosely nullary #24811
• Fix printing references to nested objects #25086
• Add error note for type mismatch involving blocks without last expression #25181
• Drop -print-lines option #24905
• Don't suggest invisible members of root imports #24999

Rewrites

• Accommodate ArrowAssoc in infix named arg migration #25255

Scaladoc

• Init MacroClassLoader in scaladoc #25141
• Scaladoc Overload Method Link Fix #25156
• Fix duplicate member entries in Scaladoc generation #24712
• Scaladoc Tests for CC #25277
• Skip generation of API pages when building reference docs #25153

Standard Library

• Remove incorrect equals implementations from ArrayBuilder #25205
• Use StringBuilder intead of StringBuffer in Regex #24576
• Update StringOps.* implementation #24786

Tooling

• Fix behavior of -Ydump-sbt-inc #25125

Typer

• Never widen constant type on selector type in matches #25197

Quotes

• Fix #25208: handle AndType(TermRef, TypeRef) in TreeUnpickler path trees #25209

Contributors

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

According to git shortlog -sn --no-merges 3.8.2..3.8.3-RC1 these are:

    80	Martin Odersky
    46	Wojciech Mazur
    26	Som Snytt
    11	Li Haoyi
    10	Tomasz G...

3.8.2

Highlights of the release

• Warn if for with many vals and overloaded map #25090
• Support :dep ... to add library dependencies in the Scala REPL #24131
• Upgrade to Scala.js 1.20.2. #24898
• Bump Scala CLI to v1.12.2 (was 1.11.0) #25217:
  • New aliases for RC and nightly Scala versions
  • Detailed changelog available in scala-cli release notes for versions: v1.12.0, v1.12.1 and v1.12.2

Other changes and fixes

Context Functions

• Inferred Contextual params are less nameable #24381

Desugaring

• A comprehension with valdef aliases is never a candidate for map elimination. #23448

Experimental: Capture Checking

• Capture Checking of Lazy Vals #24261
• Represent read-only with a classifier #24295
• Fix typing closure blocks where result type refers to a closure parameter. #24299
• Systematically recompute denotations when needed in rechecker phases #24302
• Ensure that read-only methods don't use exclusive capabilities #24311
• Handle capture parameters in dcs #24328
• Don't prematurely force info of fields with inferred types #24336
• Disallow fresh caps from parameter bounds in results #24541
• Avoid box failures and better diagnosis if they come back #24546
• Freshen all explicit arguments of type applications #24354
• Optimize and harden isCaptureChecking tests #24439
• Add Unscoped classifier #24470
• Optimization: Introduce CompactAnnotation #24679

Experimental: Seperation Checking

• Changes to Mutable #24352
• Don't crash when update is used as a modifier outside cc #24378
• Imply update only for consume methods in Mutable classes #24383
• Decompose Mutable #24495
• Add freeze wrapper (2) #24518
• Make Arrays mutable types under separation checking #24649

Experimental: Explcit Nulls

• Relax flow typing checks on Flexible Types #24278
• Do not expose flexible types #24292
• Do not search contextual function type in union types in general #24393
• Add jspecify NonNull annotation to NotNullAnnots list #24487
• Recognize Nullable annotations in explicit nulls #25237

Experimental: Global Initialization

• Global object init checker gives warning when accessing an object before its super constructor finishes #24349

Annotations

• Accommodate adapted Scala 2 annotation value #17516
• Harden Annotation.refersToParamOf #24647
• Do not allow @targetName on primary constructor too #24682

Coverage

• Fix issues with Scala.js and coverage #24769
• Make coverage support incremental compilation #24773
• Improvement: Try to optimize coverage phase #24925

Enums

• Lint enum case in outer context #24652

Exports

• Preserve select of exported member in newExpr #24570

Erasure

• Fix isJvmAccessible to handle nested protected Java classes #24625

Inline

• Allow references to erased values in types #24421
• Cast inline call results to result type, not method type #25111
• Fix "Compiler crash when calling another file's inline def that uses a private constructor" #24941

Implicits

• Avoid more constraints in result if trying views #24369

Initialization

• Skip caret when source is missing in initialization checker #23926

JVM Backend

• Preserve singleton types for final val aliases to Java enum constants #24980

Linting

• Suppression matches inlined positions #24092
• Wshadow option recognizes Wall #24469

Nullability

• Record NotNullInfo for exceptional try-catch #24320

Overloading

• Ignore selection prototypes when typing type applications #24489
• Fix varargs overload resolution with wildcard types #24669
• Fix override checking for Java methods with covariant array #24408

Parser

• Permit new with trivial end #24331
• Single line case lambda gets a region #24497
• Error tree on outdent is zero extent #23796

Pattern Matching

• Fix false exhaustivity for GADT under separate compilation #23966

Presentation Compiler

• Create extension method in infer method action #24721
• Exclude XRayModeHint for synthetics #24722
• Fix incorrect XRay hint #24738
• Improve multi-line code message rendering #24723
• Improvement: Allow passing -explain to the presentation compiler #24740
• Handle inlined tree in implicit parameter inlay hints #24762

REPL

• Improve REPL code, echo and exception highlighting with pprint and fansi #24298
• Replace REPL signal handling with raw mode jline terminal to make Ctrl-C handling work when REPL is a child process #24842
• Fix "Colon as operator part at beginning of line in REPL" #24942
• Fix "REPL dependency on scala-parallel-collections doesn't work" #25064
• Fix "Still can't use scala-parallel-collections in REPL via :dep" #25092

Reporting

• Addendum when apply error involves default arg #21133
• Forward reference error includes line numbers #22534
• Improve error messages for scope extrusion errors #24318
• Use a better span for an anonymous class #24640
• Add ErrorMessageID to -Winfer-union warnings (#25073) #25249

Scaladoc

• Allow to additional scalacOptions in Markdown code snippets #24755

Standard Library

• Enable capture checking on Tuple #24345
• Update StringOps.padTo implementation #24575
• Use String.repeat in scala.io.Source #24594
• Ensure stability of IArray.tapEach #24727

TASTy

• Pickle CompactAnnotations as regular annotations #25213
• Drop spurious applies in unpickler and inliner #25201

Transform

• Adjust purity of trait with lazy member #23788

Tuples

• Fix inconsistent typeSize calculation for TupleN vs recursive pair encodings #24743

Typer

• Dealias type of type constructor in typedAppliedTypeTree #24522
• Improve TypeVar instantiation logic #24697
• Try to instantiate TypeVars inside pt when possible #24231
• Error instead of crash when generating trees referring to skolem...

3.8.2-RC3

Backported chnages

• Add ErrorMessageID to -Winfer-union warnings (#25073) #25249
• Warn if for with many vals and overloaded map #25090
• Recognize Nullable annotations in explicit nulls #25237

Contributors

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

According to git shortlog -sn --no-merges 3.8.2-RC2..3.8.2-RC3 these are:

     3  noti0na1
     3  Wojciech Mazur
     1  Som Snytt

3.8.2-RC2

Backported chnages

• Bump Scala CLI to v1.12.2 (was v1.11.0) & coursier to 2.1.25-M23 (was 2.1.25-M21) #25217
• Pickle CompactAnnotations as regular annotations #25213
• Drop spurious applies in unpickler and inliner #25201
• Preserve singleton types for final val aliases to Java enum constants #24980
• Avoid NPE when calling hashCode on a value class wrapping null #25110
• Cast inline call results to result type, not method type #25111
• Fix "Compiler crash when calling another file's inline def that uses a private constructor" #24941
• Fix "REPL dependency on scala-parallel-collections doesn't work" #25064
• Fix "Still can't use scala-parallel-collections in REPL via :dep" #25092

Contributors

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

According to git shortlog -sn --no-merges 3.8.2-RC1..3.8.2-RC2 these are:

     7 Wojciech Mazur
     2 Li Haoyi
     2 Martin Odersky
     1 Lukas Rytz
     1 Matt Bovel
     1 Som Snytt

3.8.2-RC1

Highlights of the release

• Support :dep ... to add library dependencies in the Scala REPL, add helpful message to //> using dep "..." #24131
• Warn if type argument was inferred as union type #24258
• Upgrade to Scala.js 1.20.2. #24898

Other changes and fixes

Context Functions

• Inferred Contextual params are less nameable #24381

Desugaring

• A comprehension with valdef aliases is never a candidate for map elimination. #23448

Experimental: Capture Checking

• Capture Checking of Lazy Vals #24261
• Represent read-only with a classifier #24295
• Fix typing closure blocks where result type refers to a closure parameter. #24299
• Systematically recompute denotations when needed in rechecker phases #24302
• Ensure that read-only methods don't use exclusive capabilities #24311
• Handle capture parameters in dcs #24328
• Don't prematurely force info of fields with inferred types #24336
• Disallow fresh caps from parameter bounds in results #24541
• Avoid box failures and better diagnosis if they come back #24546
• Freshen all explicit arguments of type applications #24354
• Optimize and harden isCaptureChecking tests #24439
• Add Unscoped classifier #24470
• Optimization: Introduce CompactAnnotation #24679

Experimental: Seperation Checking

• Changes to Mutable #24352
• Don't crash when update is used as a modifier outside cc #24378
• Imply update only for consume methods in Mutable classes #24383
• Decompose Mutable #24495
• Add freeze wrapper (2) #24518
• Make Arrays mutable types under separation checking #24649

Experimental: Explcit Nulls

• Relax flow typing checks on Flexible Types #24278
• Do not expose flexible types #24292
• Do not search contextual function type in union types in general #24393
• Add jspecify NonNull annotation to NotNullAnnots list #24487

Experimental: Global Initialization

• Global object init checker gives warning when accessing an object before its super constructor finishes #24349

Annotations

• Accommodate adapted Scala 2 annotation value #17516
• Harden Annotation.refersToParamOf #24647
• Do not allow @targetName on primary constructor too #24682

Coverage

• Fix issues with Scala.js and coverage #24769
• Make coverage support incremental compilation #24773
• Improvement: Try to optimize coverage phase #24925

Enums

• Lint enum case in outer context #24652

Exports

• Preserve select of exported member in newExpr #24570

Erasure

• Fix isJvmAccessible to handle nested protected Java classes #24625

Inline

• Allow references to erased values in types #24421

Implicits

• Avoid more constraints in result if trying views #24369

Initialization

• Skip caret when source is missing in initialization checker #23926

Linting

• Suppression matches inlined positions #24092
• Wshadow option recognizes Wall #24469

Nullability

• Record NotNullInfo for exceptional try-catch #24320

Overloading

• Ignore selection prototypes when typing type applications #24489
• Fix varargs overload resolution with wildcard types #24669
• Fix override checking for Java methods with covariant array #24408

Parser

• Permit new with trivial end #24331
• Single line case lambda gets a region #24497
• Error tree on outdent is zero extent #23796

Pattern Matching

• Fix false exhaustivity for GADT under separate compilation #23966

Presentation Compiler

• Create extension method in infer method action #24721
• Exclude XRayModeHint for synthetics #24722
• Fix incorrect XRay hint #24738
• Improve multi-line code message rendering #24723
• Improvement: Allow passing -explain to the presentation compiler #24740
• Handle inlined tree in implicit parameter inlay hints #24762

REPL

• Improve REPL code, echo and exception highlighting with pprint and fansi #24298
• Replace REPL signal handling with raw mode jline terminal to make Ctrl-C handling work when REPL is a child process #24842
• Fix "Colon as operator part at beginning of line in REPL" #24942

Reporting

• Addendum when apply error involves default arg #21133
• Forward reference error includes line numbers #22534
• Improve error messages for scope extrusion errors #24318
• Use a better span for an anonymous class #24640

Scaladoc

• Allow to additional scalacOptions in Markdown code snippets #24755

Standard Library

• Enable capture checking on Tuple #24345
• Update StringOps.padTo implementation #24575
• Use String.repeat in scala.io.Source #24594
• Ensure stability of IArray.tapEach #24727

Transform

• Adjust purity of trait with lazy member #23788

Tuples

• Fix inconsistent typeSize calculation for TupleN vs recursive pair encodings #24743

Typer

• Dealias type of type constructor in typedAppliedTypeTree #24522
• Improve TypeVar instantiation logic #24697
• Try to instantiate TypeVars inside pt when possible #24231
• Error instead of crash when generating trees referring to skolems #24380
• Try to fix callee type inference in typedFunctionValue #24732
• Fix wildcardArgOK for mixed wildcard/concrete type args #25001

Union types

• Dealias in isSimpleThrowable check #24744

Quotes

• Make quotes.reflect.Position.ofMacroExpansion consider -Ymagic-offset-header #24301

Contributors

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

According to git shortlog -sn --no-merges 3.8.1..3.8.2-RC1 these are:

   101 Martin Odersky
    93 Hamza Remmal
    67 Wojciech Mazur
    34 Som Snytt
    24 noti0na1
    16 Rikito Taniguchi
     8 Oliver Bračevac
     7 Kenji Yoshida
     7 Li Haoyi
     7 Matt Bovel
     7 Natsu Kagami
     7 Tomasz Godzik
     7 Yichen Xu
     6 Jan Chyb
     6 Piotr Chabelski
     5 Zieliński Patryk
     5 dependabot[bot]
     4 HarrisL2
     3 Jamie Thompson
     3 Lukas Rytz
     2 Chua Chee Seng
     2 Fengyun Liu
     2 Guillaume Martres
     2 Lluc Santamaria Riba
     2 Sébastien Doeraene
     1 Alex1005a
     1 Bill Venners
     1 Emil Ejbyfeldt
     1 EnzeXing
     1 Evgeny Vereshchagin
     1 Jeon Yoonjae
     1 Lorenzo Gabriele
     1 Seth Tisue
     1 matsu-chara
     1 rjolly
     1 zielinsky
`...

3.8.1

Highlights of the release

Scala 3.8.1 is a hotfix release for 3.8.0.
It addresses runtime regressions found after the 3.8.0 artifacts were released, specifically JVM linkage errors affecting a small subset of Scala 2 specialized types and members.

Additional regressions

The following regressions still present in 3.8.1 will be addressed in a forthcoming 3.8.2 hotfix release:

• Some for comprehensions have incorrect behavior at runtime (#24673)
• Certain code involving calls to certain parts of the Java standard library fail to compile (#25133)

Cautious users may wish to wait for 3.8.2.

Fixed regressions

• Revert addition of new base trait to ReturnThrowable #24975
• Use uninlined version of Scala 2 standard-library in ScalaLibraryPlugin #25008
• Add missing specialized method in NumericRange #25020
• Correct the list of files to copy from Scala 2 #25033

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