Router: break before => in new given

Apparently, break after forces an indented region and fails to compile.

scalafmt-core/shared/src/main/scala/org/scalafmt/internal/FormatOps.scala

@@ -65,10 +65,12 @@ class FormatOps(
   final def getSlbEndOnLeft(start: FT)(implicit style: ScalafmtConfig): FT = {
     val nft = start.right match {
       case _: T.EOF => start
-      case _: T.Comma | _: T.Semicolon | _: T.RightArrow | _: T.Equals |
+      case _: T.Comma | _: T.Semicolon | _: T.Equals |
           _: T.Interpolation.Start | _: T.Interpolation.SpliceEnd |
           _: T.Interpolation.End | _: T.Interpolation.SpliceStart |
           _: T.Interpolation.Part => null
+      case _: T.RightArrow => // given breaks before `=>`
+        if (start.rightOwner.is[Member.ParamClauseGroup]) start else null
       case _ if start.hasBlankLine => start
       case _
           if AsInfixOp(start.rightOwner)

scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Router.scala

@@ -630,9 +630,9 @@ class Router(formatOps: FormatOps) {
             if (pcg.tparamClause.values.isEmpty) pcg.paramClauses
             else pcg.tparamClause +: pcg.paramClauses,
           ).foldLeft(Policy.noPolicy) { case (policy, pc) =>
-            val pcLast = getLast(pc)
-            val pcPolicy = Policy ? pcLast.left.is[T.RightArrow] &&
-              decideNewlinesOnlyAfterToken(nextNonCommentSameLine(pcLast))
+            val afterpc = tokenAfter(pc)
+            val pcPolicy = Policy ? afterpc.right.is[T.RightArrow] &&
+              decideNewlinesOnlyAfterToken(afterpc)
             policy ==> pcPolicy
           }
           if (nonSlbPolicy.isEmpty) Seq(Split(Space, 0))
@@ -645,16 +645,17 @@ class Router(formatOps: FormatOps) {
 
       // Given conditional arrow
       case FT(
-            left: T.RightArrow,
             _,
-            FT.LeftOwnerParent(
+            right: T.RightArrow,
+            FT.RightOwnerParent(
               pcg: Member.ParamClauseGroup,
               Some(gvn: Stat.GivenLike),
             ),
           ) =>
         val nlOnly = !style.newlines.sourceIgnored && hasBreak()
         def spaceSplit(implicit fl: FileLine) = Split(nlOnly, 0)(Space)
-        val nextParamClause = pcg.paramClauses.find(_.pos.start > left.start)
+        val nextParamClause = (pcg.tparamClause +: pcg.paramClauses)
+          .find(_.pos.end > right.end)
           .orElse(gvn.paramClauseGroups.dropWhile(_ ne pcg) match {
             case `pcg` :: pcgNext :: _ =>
               val tpc = pcgNext.tparamClause
@@ -690,13 +691,12 @@ class Router(formatOps: FormatOps) {
               )
           }
         } { npc =>
-          val nextArrow =
-            getSlbEndOnLeft(nextAfterNonCommentSameLine(getLast(npc)))
+          val nextArrow = getSlbEndOnLeft(nextNonCommentSameLine(getLast(npc)))
           val noSlb = npc.values.lengthCompare(1) != 0
           Seq(
             spaceSplit.withSingleLine(nextArrow, ignore = noSlb),
             Split(Newline, 1)
-              .withIndent(style.indent.main, nextArrow, ExpiresOn.After),
+              .withIndent(style.indent.main, nextArrow, ExpiresOn.Before),
           )
         }
 

scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces.stat

@@ -7974,9 +7974,9 @@ given [A] =>
 given [A]
  => Seq[A] = foo
 >>>
-given [A] =>
-  Seq[A] = foo
 given [A] => Seq[A] = foo
+given [A]
+  => Seq[A] = foo
 <<< scala-3.6 given 2
 maxColumn = 40
 runner.parser = source
@@ -7986,10 +7986,10 @@ given [A] => (Seq[A] =>
 given [A] => (Seq[A]
  => List[A]) => List[A] = foo
 >>>
-given [A] => (Seq[A] => List[A]) =>
-  List[A] = foo
-given [A] => (Seq[A] => List[A]) =>
-  List[A] = foo
+given [A] => (Seq[A] => List[A])
+  => List[A] = foo
+given [A] => (Seq[A] => List[A])
+  => List[A] = foo
 <<< scala-3.6 given 3
 maxColumn = 40
 runner.parser = source
@@ -7999,11 +7999,11 @@ given foo: (a: A) =>
 given foo: (a: A)
  => [B, C <: AnyRef] => (b: B[A], C) => List[A] = foo
 >>>
-given foo: (a: A) =>
-  [B, C <: AnyRef] => (b: B[A], C) =>
-  List[A] = foo
-given foo: (a: A) => [B, C <: AnyRef] =>
-  (b: B[A], C) => List[A] = foo
+given foo: (a: A) => [B, C <: AnyRef]
+  => (b: B[A], C) => List[A] = foo
+given foo: (a: A)
+  => [B, C <: AnyRef] => (b: B[A], C)
+  => List[A] = foo
 <<< don't rewrite complex infix to braces
 rewrite.redundantBraces.oneStatApply.bracesMinSpan = 1
 rewrite.rules = [RedundantBraces, RedundantParens]

scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_fold.stat

@@ -7665,10 +7665,10 @@ given [A] => (Seq[A] =>
 given [A] => (Seq[A]
  => List[A]) => List[A] = foo
 >>>
-given [A] => (Seq[A] => List[A]) =>
-  List[A] = foo
-given [A] => (Seq[A] => List[A]) =>
-  List[A] = foo
+given [A] => (Seq[A] => List[A])
+  => List[A] = foo
+given [A] => (Seq[A] => List[A])
+  => List[A] = foo
 <<< scala-3.6 given 3
 maxColumn = 40
 runner.parser = source
@@ -7678,10 +7678,10 @@ given foo: (a: A) =>
 given foo: (a: A)
  => [B, C <: AnyRef] => (b: B[A], C) => List[A] = foo
 >>>
-given foo: (a: A) => [B, C <: AnyRef] =>
-  (b: B[A], C) => List[A] = foo
-given foo: (a: A) => [B, C <: AnyRef] =>
-  (b: B[A], C) => List[A] = foo
+given foo: (a: A) => [B, C <: AnyRef]
+  => (b: B[A], C) => List[A] = foo
+given foo: (a: A) => [B, C <: AnyRef]
+  => (b: B[A], C) => List[A] = foo
 <<< don't rewrite complex infix to braces
 rewrite.redundantBraces.oneStatApply.bracesMinSpan = 1
 rewrite.rules = [RedundantBraces, RedundantParens]

scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_keep.stat

@@ -7997,9 +7997,9 @@ given [A] =>
 given [A]
  => Seq[A] = foo
 >>>
-given [A] =>
-  Seq[A] = foo
 given [A] => Seq[A] = foo
+given [A]
+  => Seq[A] = foo
 <<< scala-3.6 given 2
 maxColumn = 40
 runner.parser = source
@@ -8009,10 +8009,10 @@ given [A] => (Seq[A] =>
 given [A] => (Seq[A]
  => List[A]) => List[A] = foo
 >>>
-given [A] => (Seq[A] => List[A]) =>
-  List[A] = foo
-given [A] => (Seq[A] => List[A]) =>
-  List[A] = foo
+given [A] => (Seq[A] => List[A])
+  => List[A] = foo
+given [A] => (Seq[A] => List[A])
+  => List[A] = foo
 <<< scala-3.6 given 3
 maxColumn = 40
 runner.parser = source
@@ -8022,11 +8022,11 @@ given foo: (a: A) =>
 given foo: (a: A)
  => [B, C <: AnyRef] => (b: B[A], C) => List[A] = foo
 >>>
-given foo: (a: A) =>
-  [B, C <: AnyRef] => (b: B[A], C) =>
-  List[A] = foo
-given foo: (a: A) => [B, C <: AnyRef] =>
-  (b: B[A], C) => List[A] = foo
+given foo: (a: A) => [B, C <: AnyRef]
+  => (b: B[A], C) => List[A] = foo
+given foo: (a: A)
+  => [B, C <: AnyRef] => (b: B[A], C)
+  => List[A] = foo
 <<< don't rewrite complex infix to braces
 rewrite.redundantBraces.oneStatApply.bracesMinSpan = 1
 rewrite.rules = [RedundantBraces, RedundantParens]

scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_unfold.stat

@@ -8306,10 +8306,12 @@ given [A] => (Seq[A] =>
 given [A] => (Seq[A]
  => List[A]) => List[A] = foo
 >>>
-given [A] => (Seq[A] => List[A]) =>
-  List[A] = foo
-given [A] => (Seq[A] => List[A]) =>
-  List[A] = foo
+given [A]
+  => (Seq[A] => List[A])
+  => List[A] = foo
+given [A]
+  => (Seq[A] => List[A])
+  => List[A] = foo
 <<< scala-3.6 given 3
 maxColumn = 40
 runner.parser = source
@@ -8319,10 +8321,14 @@ given foo: (a: A) =>
 given foo: (a: A)
  => [B, C <: AnyRef] => (b: B[A], C) => List[A] = foo
 >>>
-given foo: (a: A) => [B, C <: AnyRef] =>
-  (b: B[A], C) => List[A] = foo
-given foo: (a: A) => [B, C <: AnyRef] =>
-  (b: B[A], C) => List[A] = foo
+given foo: (a: A)
+  => [B, C <: AnyRef]
+  => (b: B[A], C)
+  => List[A] = foo
+given foo: (a: A)
+  => [B, C <: AnyRef]
+  => (b: B[A], C)
+  => List[A] = foo
 <<< don't rewrite complex infix to braces
 rewrite.redundantBraces.oneStatApply.bracesMinSpan = 1
 rewrite.rules = [RedundantBraces, RedundantParens]

scalafmt-tests/shared/src/test/scala/org/scalafmt/FormatTests.scala

@@ -144,7 +144,7 @@ class FormatTests extends FunSuite with CanRunTests with FormatAssertions {
     val explored = Debug.explored.get()
     logger.debug(s"Total explored: $explored")
     if (!onlyUnit && !onlyManual)
-      assertEquals(explored, 1253679, "total explored")
+      assertEquals(explored, 1253866, "total explored")
     val results = debugResults.result()
     // TODO(olafur) don't block printing out test results.
     // I don't want to deal with scalaz's Tasks :'(