Router: fix enclosed case body w/ paren after NL

scalameta · Sep 15, 2024 · bd565e9 · bd565e9
1 parent df90d9a
commit bd565e9
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Showing 6 changed files with 78 additions and 32 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
@@ -1759,12 +1759,14 @@ class FormatOps(
     })
 
   // Redundant () delims around case statements
-  def isCaseBodyEnclosedAsBlock(ft: FormatToken, caseStat: CaseTree)(implicit
-      beforeMultiline: Newlines.SourceHints,
-  ): Boolean = {
+  def getClosingIfCaseBodyEnclosedAsBlock(
+      postArrowFt: FormatToken,
+      caseStat: CaseTree,
+  )(implicit beforeMultiline: Newlines.SourceHints): Option[FormatToken] = {
     val body = caseStat.body
-    (ft.noBreak || beforeMultiline.ignoreSourceSplit) &&
-    body.eq(ft.meta.rightOwner) && isBodyEnclosedAsBlock(body)
+    val ok = body.eq(postArrowFt.meta.rightOwner) &&
+      (beforeMultiline.ignoreSourceSplit || postArrowFt.noBreak)
+    if (ok) getClosingIfBodyEnclosedAsBlock(body) else None
   }
 
   // Redundant () delims around body

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
@@ -543,7 +543,8 @@ class Router(formatOps: FormatOps) {
           )
           implicit val beforeMultiline = style.newlines.getBeforeMultiline
           if (
-            isCaseBodyABlock(nft, owner) || isCaseBodyEnclosedAsBlock(nft, owner)
+            isCaseBodyABlock(nft, owner) ||
+            getClosingIfCaseBodyEnclosedAsBlock(nft, owner).isDefined
           ) Seq(baseSplit)
           else if (nft.right.is[T.KwCase]) Seq(nlSplit(nft)(0))
           else if (hasBreak() && !beforeMultiline.ignoreSourceSplit)
@@ -2185,29 +2186,30 @@ class Router(formatOps: FormatOps) {
           if (bodyBlock || (arrowFt ne postArrowFt) && postArrowFt.hasBreak)
             NoPolicy
           else {
+            // postArrowFt points to non-comment after arrowFt
+            // possibly on next line without intervening comments
             implicit val beforeMultiline = style.newlines.getBeforeMultiline
-            if (!isCaseBodyEnclosedAsBlock(postArrowFt, owner))
+            getClosingIfCaseBodyEnclosedAsBlock(postArrowFt, owner).fold {
               Policy ? beforeMultiline.in(Newlines.fold, Newlines.keep) ||
               defaultPolicy
-            else {
-              val postParenFt = nextNonCommentSameLineAfter(postArrowFt)
-              val lparen = postParenFt.left
-              val rparen = matching(lparen)
-              if (postParenFt.right.start >= rparen.start) defaultPolicy
-              else {
-                val indent = style.indent.main
-                val lindents = Seq(
-                  Indent(indent, rparen, Before),
-                  Indent(-indent, expire, After),
-                )
-                val lmod = NewlineT(noIndent = rhsIsCommentedOut(postParenFt))
-                val lsplit = Seq(Split(lmod, 0).withIndents(lindents))
-                val rsplit = Seq(Split(Newline, 0))
-                Policy.after(lparen, prefix = "CASE[(]") {
-                  case d: Decision if d.formatToken eq postParenFt => lsplit
-                } ==> Policy.on(rparen, prefix = "CASE[)]") {
-                  case d: Decision if d.formatToken.right eq rparen => rsplit
-                }
+            } { rparenFt =>
+              val lparentFt = next(postArrowFt)
+              val postParenFt = nextNonCommentSameLine(lparentFt)
+              val rparen = rparenFt.right
+              val indent = style.indent.main
+              val lindents = Seq(
+                Indent(indent, rparen, Before),
+                Indent(-indent, expire, After),
+              )
+              val lmod = NewlineT(noIndent = rhsIsCommentedOut(postParenFt))
+              val lsplit = Seq(Split(lmod, 0).withIndents(lindents))
+              val rsplit = Seq(Split(Newline, 0))
+              Policy.after(postParenFt.left, prefix = "CASE[(]") {
+                case Decision(`postParenFt`, _) => lsplit
+                // fires only if there's a comment between lparentFt and postParentFt
+                case Decision(`lparentFt`, _) => Seq(Split(Space, 0))
+              } ==> Policy.on(rparen, prefix = "CASE[)]") {
+                case Decision(`rparenFt`, _) => rsplit
               }
             }
           }

diff --git a/scalafmt-tests/src/test/resources/newlines/source_classic.stat b/scalafmt-tests/src/test/resources/newlines/source_classic.stat
@@ -9206,7 +9206,14 @@ object a {
   }
 }
 >>>
-org.scalafmt.util.FormatException: java.util.NoSuchElementException: Missing matching token index Comment( c1a) [43..49) @2:18: `// c1a`
+object a {
+  foo match {
+    case bar => ( // c1a
+      // c2a
+      qux
+    )
+  }
+}
 <<< #4133 case body enclosed, no break before lparen, break after lparen
 object a {
   foo match {

diff --git a/scalafmt-tests/src/test/resources/newlines/source_fold.stat b/scalafmt-tests/src/test/resources/newlines/source_fold.stat
@@ -8578,7 +8578,14 @@ object a {
   }
 }
 >>>
-org.scalafmt.util.FormatException: java.util.NoSuchElementException: Missing matching token index Comment( c1a) [43..49) @2:18: `// c1a`
+object a {
+  foo match {
+    case bar => ( // c1a
+      // c2a
+      qux
+    )
+  }
+}
 <<< #4133 case body enclosed, no break before lparen, break after lparen
 object a {
   foo match {
@@ -8610,7 +8617,14 @@ object a {
   }
 }
 >>>
-org.scalafmt.util.FormatException: java.util.NoSuchElementException: Missing matching token index Comment( c1a) [49..55) @3:8: `// c1a`
+object a {
+  foo match {
+    case bar => ( // c1a
+      // c2a
+      qux
+    )
+  }
+}
 <<< #4133 case body enclosed, break before lparen, comment after arrow
 object a {
   foo match {

diff --git a/scalafmt-tests/src/test/resources/newlines/source_keep.stat b/scalafmt-tests/src/test/resources/newlines/source_keep.stat
@@ -9004,7 +9004,14 @@ object a {
   }
 }
 >>>
-org.scalafmt.util.FormatException: java.util.NoSuchElementException: Missing matching token index Comment( c1a) [43..49) @2:18: `// c1a`
+object a {
+  foo match {
+    case bar => ( // c1a
+      // c2a
+      qux
+    )
+  }
+}
 <<< #4133 case body enclosed, no break before lparen, break after lparen
 object a {
   foo match {

diff --git a/scalafmt-tests/src/test/resources/newlines/source_unfold.stat b/scalafmt-tests/src/test/resources/newlines/source_unfold.stat
@@ -9302,7 +9302,14 @@ object a {
   }
 }
 >>>
-org.scalafmt.util.FormatException: java.util.NoSuchElementException: Missing matching token index Comment( c1a) [43..49) @2:18: `// c1a`
+object a {
+  foo match {
+    case bar => ( // c1a
+      // c2a
+      qux
+    )
+  }
+}
 <<< #4133 case body enclosed, no break before lparen, break after lparen
 object a {
   foo match {
@@ -9334,7 +9341,14 @@ object a {
   }
 }
 >>>
-org.scalafmt.util.FormatException: java.util.NoSuchElementException: Missing matching token index Comment( c1a) [49..55) @3:8: `// c1a`
+object a {
+  foo match {
+    case bar => ( // c1a
+      // c2a
+      qux
+    )
+  }
+}
 <<< #4133 case body enclosed, break before lparen, comment after arrow
 object a {
   foo match {