RedundantBraces: replace ( with { more often

scalafmt-core/shared/src/main/scala/org/scalafmt/rewrite/RedundantBraces.scala

@@ -165,28 +165,42 @@ class RedundantBraces(implicit val ftoks: FormatTokens)
   private def onLeftParen(implicit ft: FT, style: ScalafmtConfig): Replacement = {
     val rt = ft.right
 
-    def replaceWithBrace(owner: Option[Tree] = None, claim: List[Int] = Nil) = {
+    def replaceWithBrace(claim: List[Int], owner: Option[Tree] = None) = {
       val lb = new T.LeftBrace(rt.input, rt.dialect, rt.start)
       replaceToken("{", owner = owner, claim = claim)(lb)
     }
 
     ft.rightOwner match {
       case ta @ Term.ArgClause(arg :: Nil, _)
           if !ta.parent.is[Init] && getOpeningParen(ta).contains(rt) =>
-        def replaceWithNextBrace() = ftoks.nextNonCommentAfter(ft) match {
+        def replaceWithNextBrace(claimToo: List[Int] = Nil) = ftoks
+          .nextNonCommentAfter(ft) match {
           case FT(lt, _: T.LeftBrace, m) =>
-            val claim = m.idx :: Nil
+            val claim = m.idx :: claimToo
             if (lt eq rt) removeToken(claim = claim)
             else replaceWithBrace(owner = Some(m.rightOwner), claim = claim)
-          case _ => replaceWithBrace(Some(arg))
+          case _ => replaceWithBrace(owner = Some(arg), claim = claimToo)
         }
         arg match {
           // single-arg apply of a partial function or optionally any arg
           // a({ case b => c; d }) change to a { case b => c; d }
           case _: Term.PartialFunction => replaceWithNextBrace()
           case b: Term.Block =>
-            val ok = getTreeSingleExpr(b).is[Term.PartialFunction]
-            if (ok) replaceWithNextBrace() else null
+            val stat = getBlockSingleStat(b)
+            stat.flatMap(getTreeSingleExpr) match {
+              case Some(f: Term.FunctionTerm) =>
+                getBlockToReplaceAsFuncBodyInSingleArgApply(ta, f) match {
+                  case Some((xb, xlb)) =>
+                    if (canRewriteStatWithParens(xb)) null
+                    else replaceWithNextBrace(claimToo = xlb.idx - 1 :: Nil)
+                  case _ => replaceWithNextBrace()
+                }
+              case Some(s: Term)
+                  if okLineSpan(b) &&
+                    !stat.exists(ftoks.tokenAfter(_).right.is[T.Semicolon]) &&
+                    canRewriteStatWithParens(s) => null
+              case _ => replaceWithNextBrace()
+            }
           case f: Term.FunctionTerm =>
             getBlockToReplaceAsFuncBodyInSingleArgApply(ta, f) match {
               case Some((_, xlb)) => replaceWithBrace(claim = xlb.idx - 1 :: Nil)

scalafmt-tests/shared/src/test/resources/rewrite/RedundantBraces.stat

@@ -1573,7 +1573,7 @@ object a {
 }
 >>>
 object a {
-  foo({ bar = baz })
+  foo { bar = baz }
   foo({ bar = baz }, qux)
 }
 <<< #3296
@@ -1612,10 +1612,10 @@ foo.mtd({
   },
 )
 >>>
-foo.mtd({
+foo.mtd {
   x + 1
   x + 2
-})
+}
 <<< rewrite with trailing commas: block simple, !allowFolding
 rewrite.trailingCommas.style = keep
 rewrite.trailingCommas.allowFolding = false
@@ -1626,10 +1626,10 @@ foo.mtd({
   },
 )
 >>>
-foo.mtd({
+foo.mtd {
   x + 1
   x + 2
-})
+}
 <<< rewrite with trailing commas: func, allowFolding
 rewrite.trailingCommas.style = keep
 rewrite.trailingCommas.allowFolding = true
@@ -1640,10 +1640,10 @@ foo.mtd1({ x =>
   },
 )
 >>>
-foo.mtd1({ x =>
+foo.mtd1 { x =>
   x + 1
   x + 2
-})
+}
 <<< rewrite with trailing commas: func, !allowFolding
 rewrite.trailingCommas.style = keep
 rewrite.trailingCommas.allowFolding = false
@@ -1654,10 +1654,10 @@ foo.mtd1({ x =>
   },
 )
 >>>
-foo.mtd1({ x =>
+foo.mtd1 { x =>
   x + 1
   x + 2
-})
+}
 <<< rewrite with trailing commas: func in parens, infix after, allowFolding
 rewrite.trailingCommas.style = keep
 rewrite.trailingCommas.allowFolding = true
@@ -1720,12 +1720,10 @@ foo.mtd(
     },
   )
 >>>
-foo.mtd(
-  { x =>
-    x + 1
-    x + 2
-  },
-)
+foo.mtd { x =>
+  x + 1
+  x + 2
+}
 <<< rewrite with trailing commas: func in parens and braces, !allowFolding
 rewrite.rules = [RedundantBraces, RedundantParens]
 rewrite.trailingCommas.style = keep
@@ -1738,12 +1736,10 @@ foo.mtd(
     },
   )
 >>>
-foo.mtd(
-  { x =>
-    x + 1
-    x + 2
-  },
-)
+foo.mtd { x =>
+  x + 1
+  x + 2
+}
 <<< rewrite with trailing commas: func in parens and braces, infix after, allowFolding
 rewrite.rules = [RedundantBraces, RedundantParens]
 rewrite.trailingCommas.style = keep
@@ -1769,22 +1765,16 @@ object a {
 }
 >>>
 object a {
-  mtd1(
-    { x =>
-      x + 1
-    },
-  ) + mtd2(
-    { x =>
-      x + 1
-      x + 2
-    },
-  ) + mtd3(
-    { x =>
-      x + 1
-      x + 2
-      x + 3
-    },
-  )
+  mtd1 { x =>
+    x + 1
+  } + mtd2 { x =>
+    x + 1
+    x + 2
+  } + mtd3 { x =>
+    x + 1
+    x + 2
+    x + 3
+  }
 }
 <<< rewrite with trailing commas: func in parens and braces, infix after, !allowFolding
 rewrite.rules = [RedundantBraces, RedundantParens]
@@ -1811,22 +1801,16 @@ object a {
 }
 >>>
 object a {
-  mtd1(
-    { x =>
-      x + 1
-    },
-  ) + mtd2(
-    { x =>
-      x + 1
-      x + 2
-    },
-  ) + mtd3(
-    { x =>
-      x + 1
-      x + 2
-      x + 3
-    },
-  )
+  mtd1 { x =>
+    x + 1
+  } + mtd2 { x =>
+    x + 1
+    x + 2
+  } + mtd3 { x =>
+    x + 1
+    x + 2
+    x + 3
+  }
 }
 <<< rewrite with trailing commas: partial func, allowFolding
 rewrite.trailingCommas.style = keep
@@ -1867,11 +1851,11 @@ foo.mtd({
   },
 )
 >>>
-foo.mtd({
+foo.mtd {
   bar match {
     case x => x + 1
   }
-})
+}
 <<< rewrite with trailing commas: match, !allowFolding
 rewrite.trailingCommas.style = keep
 rewrite.trailingCommas.allowFolding = false
@@ -1883,11 +1867,11 @@ foo.mtd({
   },
 )
 >>>
-foo.mtd({
+foo.mtd {
   bar match {
     case x => x + 1
   }
-})
+}
 <<< with infix (from sbt-scalafmt plugin)
 maxColumn = 80
 newlines.source = fold
@@ -2233,7 +2217,7 @@ run { worklist.push(startBlock); }
 <<< #4133 can't rewrite with parens if semicolon, without redundant parens
 run( { worklist.push(startBlock); } )
 >>>
-run({ worklist.push(startBlock); })
+run { worklist.push(startBlock); }
 <<< #4133 rewrites with assignment and infix chain
 maxColumn = 76
 rewrite.redundantBraces {

scalafmt-tests/shared/src/test/resources/rewrite/RedundantBraces2.stat

@@ -375,10 +375,10 @@ object a {
 }
 >>>
 object a {
-  val switchVersion: Command = Command.args("+~", "<version> <args>")({
+  val switchVersion: Command = Command.args("+~", "<version> <args>") {
     (initialState: State, args: Seq[String]) =>
       def run = ???
-  })
+  }
 }
 <<< block within parens: single-stat func with multi-stat body
 object a {
@@ -391,11 +391,11 @@ object a {
 }
 >>>
 object a {
-  val switchVersion: Command = Command.args("+~", "<version> <args>")({
+  val switchVersion: Command = Command.args("+~", "<version> <args>") {
     (initialState: State, args: Seq[String]) =>
       val requestedVersionPrefix = args.head
       def run = ???
-  })
+  }
 }
 <<< block within parens: single-stat defn
 object a {
@@ -405,9 +405,9 @@ object a {
 }
 >>>
 object a {
-  val switchVersion: Command = Command.args("+~", "<version> <args>")({
+  val switchVersion: Command = Command.args("+~", "<version> <args>") {
     val foo = ???
-  })
+  }
 }
 <<< block within parens: multi-stat
 object a {
@@ -419,9 +419,9 @@ object a {
 }
 >>>
 object a {
-  val switchVersion: Command = Command.args("+~", "<version> <args>")({
+  val switchVersion: Command = Command.args("+~", "<version> <args>") {
     val foo = 0
     val bar = 1
     foo + bar
-  })
+  }
 }

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, 1203371, "total explored")
+      assertEquals(explored, 1203082, "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 :'(