From 3f8108347253f015cb3ba9db5758bb245f82da18 Mon Sep 17 00:00:00 2001
From: Albert Meltzer <7529386+kitbellew@users.noreply.github.com>
Date: Mon, 3 Mar 2025 20:09:38 -0800
Subject: [PATCH] Splits: ensure break between `yield` and `case`

---
 .../src/main/scala/org/scalafmt/internal/Splits.scala |  6 ++++++
 .../src/test/resources/scala3/OptionalBraces.stat     |  8 ++------
 .../test/resources/scala3/OptionalBraces_fold.stat    |  8 +++-----
 .../test/resources/scala3/OptionalBraces_keep.stat    |  9 ++-------
 .../test/resources/scala3/OptionalBraces_unfold.stat  | 11 +++--------
 .../src/test/scala/org/scalafmt/FormatTests.scala     |  2 +-
 6 files changed, 17 insertions(+), 27 deletions(-)

diff --git a/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Splits.scala b/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Splits.scala
index 31f03bb8b..7a2df41a5 100644
--- a/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Splits.scala
+++ b/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Splits.scala
@@ -3381,6 +3381,12 @@ object SplitsAfterYield extends Splits {
       case t: Term.ForYield => Some(t.body)
       case _ => None
     }).fold(Seq.empty[Split]) {
+      case b: Term.PartialFunction
+          if dialect.allowSignificantIndentation &&
+            nextNonComment(ft).right.is[T.KwCase] =>
+        val split = Split(Newline, 0)
+          .withIndent(cfg.indent.getSignificant, getLast(b), ExpiresOn.After)
+        Seq(split)
       case b: Tree.Block
           if right.is[T.LeftBrace] &&
             matchingOptRight(ft).exists(_.idx >= getLast(b).idx) =>
diff --git a/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces.stat b/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces.stat
index a415e98c1..5e186ca2b 100644
--- a/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces.stat
+++ b/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces.stat
@@ -8533,10 +8533,6 @@ for
 yield
   case Some(x) => foo
 >>>
-test does not parse: [dialect scala3] illegal start of simple expression
 for foo <- Some(42)
-yield case Some(x) => foo
-      ^
-====== full result: ======
-for foo <- Some(42)
-yield case Some(x) => foo
+yield
+   case Some(x) => foo
diff --git a/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_fold.stat b/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_fold.stat
index 2c97df831..bd57bebf0 100644
--- a/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_fold.stat
+++ b/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_fold.stat
@@ -8196,8 +8196,6 @@ for
 yield
   case Some(x) => foo
 >>>
-test does not parse: [dialect scala3] illegal start of simple expression
-for foo <- Some(42) yield case Some(x) => foo
-                          ^
-====== full result: ======
-for foo <- Some(42) yield case Some(x) => foo
+for foo <- Some(42)
+yield
+   case Some(x) => foo
diff --git a/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_keep.stat b/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_keep.stat
index 656c61c14..529b5cb52 100644
--- a/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_keep.stat
+++ b/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_keep.stat
@@ -8555,12 +8555,7 @@ for
 yield
   case Some(x) => foo
 >>>
-test does not parse: [dialect scala3] illegal start of simple expression
 for
    foo <- Some(42)
-yield case Some(x) => foo
-      ^
-====== full result: ======
-for
-   foo <- Some(42)
-yield case Some(x) => foo
+yield
+   case Some(x) => foo
diff --git a/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_unfold.stat b/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_unfold.stat
index 84ae37574..a4409a44e 100644
--- a/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_unfold.stat
+++ b/scalafmt-tests/shared/src/test/resources/scala3/OptionalBraces_unfold.stat
@@ -8883,12 +8883,7 @@ for
 yield
   case Some(x) => foo
 >>>
-test does not parse: [dialect scala3] illegal start of simple expression
 for foo <- Some(42)
-yield case Some(x) =>
-      ^
-  foo
-====== full result: ======
-for foo <- Some(42)
-yield case Some(x) =>
-  foo
+yield
+   case Some(x) =>
+     foo
diff --git a/scalafmt-tests/shared/src/test/scala/org/scalafmt/FormatTests.scala b/scalafmt-tests/shared/src/test/scala/org/scalafmt/FormatTests.scala
index b389e5580..127f22a24 100644
--- a/scalafmt-tests/shared/src/test/scala/org/scalafmt/FormatTests.scala
+++ b/scalafmt-tests/shared/src/test/scala/org/scalafmt/FormatTests.scala
@@ -148,7 +148,7 @@ class FormatTests extends FunSuite with CanRunTests with FormatAssertions {
     val explored = Debug.explored.get()
     logger.debug(s"Total explored: $explored")
     if (!onlyUnit && !onlyManual)
-      assertEquals(explored, 2536504, "total explored")
+      assertEquals(explored, 2536664, "total explored")
     // TODO(olafur) don't block printing out test results.
     TestPlatformCompat.executeAndWait(PlatformFileOps.writeFile(
       FileOps.getPath("target", "index.html"),