Router: for/infix before select like fewer-braces

scalameta · Dec 10, 2024 · 97f3f3a · 97f3f3a
1 parent 68c25bb
commit 97f3f3a
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Showing 7 changed files with 424 additions and 522 deletions.
diff --git a/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/FormatOps.scala b/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/FormatOps.scala
@@ -1281,6 +1281,17 @@ class FormatOps(
       enclosed: Boolean = true,
   ): Option[SelectLike] = findPrevSelectAndApply(tree.qual, enclosed)._1
 
+  @tailrec
+  final def findFirstSelect(
+      tree: Tree,
+      enclosed: Boolean,
+      select: Option[SelectLike] = None,
+  ): Option[SelectLike] = findPrevSelectAndApply(tree, enclosed) match {
+    case (x @ Some(prevSelect), _) =>
+      findFirstSelect(prevSelect.qual, enclosed, x)
+    case _ => select
+  }
+
   @tailrec
   private def findLastApplyAndNextSelectEnclosed(
       tree: Tree,
@@ -2161,7 +2172,9 @@ class FormatOps(
               case x: Term.Block => getBlockWithNonSingleTermStat(x)
               case x: Tree.CasesBlock => Some(x)
               case _ => None
-            }).flatMap(x => WithStats(nft, x.stats.headOption, b, Some(t)))
+            }).fold(getMaybeFewerBracesSelectSplits(b))(x =>
+              WithStats(nft, x.stats.headOption, b, Some(t)),
+            )
           case _ => BlockImpl.create(nft)
         }
     }
@@ -2350,6 +2363,40 @@ class FormatOps(
       getSplits(tree, forceNL, danglingKeyword)
     }
 
+    private def getMaybeFewerBracesSelectSplits(body: Tree)(implicit
+        ft: FT,
+        style: ScalafmtConfig,
+    ) = findFirstSelect(body, enclosed = true).filter(_.qual match {
+      case q @ (_: Term.ForClause | _: Term.ApplyInfix |
+          _: Term.SelectPostfix) => !isEnclosedInMatching(q)
+      case _ => false
+    }).map { selectLike =>
+      new OptionalBracesRegion {
+        def splits: Option[Seq[Split]] = {
+          val noFbIndent = style.getFewerBraces() == Indents.FewerBraces.never
+          val indentLen =
+            if (noFbIndent) style.indent.getSignificant
+            else style.indent.main + style.indent.getSignificant
+          val dot = prev(prevNonCommentBefore(selectLike.nameFt))
+          val beforeDot = prevNonCommentSameLine(dot)
+          val policy = Policy.End <= beforeDot ==>
+            Policy.onRight(dot, "NL-NOIND-SELECT") {
+              case Decision(`beforeDot`, ss) => ss.flatMap { s =>
+                  if ((dot eq beforeDot) && !s.isNL) None
+                  else Some(s.deActivateFor(SplitTag.SelectChainFirstNL))
+                }
+              case Decision(_, ss) => ss
+                  .map(_.deActivateFor(SplitTag.SelectChainFirstNL))
+            }
+          val nlSplit = Split(Newline2x(ft), 1, policy = policy)
+            .withIndent(indentLen, beforeDot, ExpiresOn.After)
+          Some(Seq(nlSplit))
+        }
+        def rightBrace: Option[FT] = treeLast(body)
+        def owner: Option[Tree] = body.parent
+      }
+    }
+
     private class WithStats private (
         nft: FT,
         body: Tree,

diff --git a/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Router.scala b/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Router.scala
@@ -1735,6 +1735,8 @@ class Router(formatOps: FormatOps) {
                 p.casesBlock
             case p: Term.NewAnonymous => getHeadOpt(p.templ.body)
                 .exists(_.left.is[T.Colon])
+            case _: Term.ForClause | _: Term.ApplyInfix |
+                _: Term.SelectPostfix => true
             case _ => false
           }) && !isEnclosedInMatching(tree)
         val fewerBracesLike = checkFewerBraces(thisSelect.qual)