Rewrite: replace delimiters with space

Parens/braces serve as delimiters (such as in "if(x"), so when we remove them, we must ensure that tokens before and after continue to be clearly separated. For that, let's just replace these delimiters with spaces, as formatter will remove any redundant space later.
scalameta · Jul 25, 2020 · fdc6ca3 · fdc6ca3
1 parent af06ddc
commit fdc6ca3
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Showing 5 changed files with 27 additions and 33 deletions.
diff --git a/scalafmt-core/shared/src/main/scala/org/scalafmt/rewrite/RedundantBraces.scala b/scalafmt-core/shared/src/main/scala/org/scalafmt/rewrite/RedundantBraces.scala
@@ -78,17 +78,13 @@ class RedundantBraces(implicit ctx: RewriteCtx) extends RewriteSession {
       arg.value.head == '_' || isLiteralIdentifier(arg)
 
     t.parts.tail.zip(t.args).foreach {
-      case (Lit(value: String), arg @ Term.Name(_))
+      case (Lit.String(value), arg: Term.Name)
           if !isIdentifierAtStart(value) && !shouldTermBeEscaped(arg) =>
-        val openBrace = prevToken(arg.tokens.head)
-        val closeBrace = nextToken(arg.tokens.head)
-        (openBrace, closeBrace) match {
-          case (LeftBrace(), RightBrace()) =>
-            ctx.addPatchSet(
-              TokenPatch.Remove(openBrace),
-              TokenPatch.Remove(closeBrace)
-            )
-          case _ =>
+        val open = prevToken(arg.tokens.head)
+        if (open.is[LeftBrace]) {
+          val close = nextToken(arg.tokens.head)
+          if (close.is[RightBrace])
+            ctx.addPatchSet(TokenPatch.Remove(open), TokenPatch.Remove(close))
         }
       case _ =>
     }
@@ -140,8 +136,7 @@ class RedundantBraces(implicit ctx: RewriteCtx) extends RewriteSession {
           val lparen = ctx.getMatching(rparen)
           implicit val builder = Seq.newBuilder[TokenPatch]
           builder += TokenPatch.Replace(lparen, lbrace.text)
-          builder += TokenPatch.Remove(lbrace)
-          builder += TokenPatch.Remove(rparen)
+          removeBraces(lbrace, rparen)
           ctx.removeLFToAvoidEmptyLine(rparen)
           ctx.addPatchSet(builder.result(): _*)
         }
@@ -161,8 +156,7 @@ class RedundantBraces(implicit ctx: RewriteCtx) extends RewriteSession {
         val lbrace = ctx.getMatching(rbrace)
         if (lbrace.start <= body.tokens.head.start) {
           implicit val builder = Seq.newBuilder[TokenPatch]
-          builder += TokenPatch.Remove(lbrace)
-          builder += TokenPatch.Remove(rbrace)
+          removeBraces(lbrace, rbrace)
           ctx.removeLFToAvoidEmptyLine(rbrace)
           ctx.addPatchSet(builder.result(): _*)
         }
@@ -207,8 +201,7 @@ class RedundantBraces(implicit ctx: RewriteCtx) extends RewriteSession {
             true
         }
         if (ok) {
-          builder += TokenPatch.Remove(open)
-          builder += TokenPatch.Remove(close)
+          removeBraces(open, close)
           ctx.addPatchSet(builder.result(): _*)
         }
       }
@@ -343,4 +336,11 @@ class RedundantBraces(implicit ctx: RewriteCtx) extends RewriteSession {
   private def getSingleStatIfLineSpanOk(b: Term.Block): Option[Stat] =
     getBlockSingleStat(b).filter(getTermLineSpan(_) <= settings.maxLines)
 
+  private def removeBraces(lbrace: Token, rbrace: Token)(implicit
+      builder: Rewrite.PatchBuilder
+  ): Unit = {
+    builder += TokenPatch.AddLeft(lbrace, " ", keepTok = false)
+    builder += TokenPatch.AddRight(rbrace, " ", keepTok = false)
+  }
+
 }
diff --git a/scalafmt-core/shared/src/main/scala/org/scalafmt/rewrite/RedundantParens.scala b/scalafmt-core/shared/src/main/scala/org/scalafmt/rewrite/RedundantParens.scala
@@ -93,21 +93,15 @@ class RedundantParens(implicit ctx: RewriteCtx) extends RewriteSession {
       val offBeg = minToKeep
       if (offBeg <= offEnd) {
         implicit val builder = Seq.newBuilder[TokenPatch]
-        (offBeg to offEnd).foreach { x =>
+        // replace outer with space, to avoid joining with an adjacent keyword
+        builder += TokenPatch.AddLeft(toks(beg + offBeg), " ", keepTok = false)
+        builder += TokenPatch.AddRight(toks(end - offBeg), " ", keepTok = false)
+        ((offBeg + 1) to offEnd).foreach { x =>
           builder += TokenPatch.Remove(toks(beg + x))
           builder += TokenPatch.Remove(toks(end - x))
         }
         ctx.removeLFToAvoidEmptyLine(toks(beg + offBeg), toks(beg + offEnd))
         ctx.removeLFToAvoidEmptyLine(toks(end - offEnd), toks(end - offBeg))
-
-        if (beg > 0) {
-          toks(beg - 1) match {
-            case t: Token.KwYield =>
-              builder += TokenPatch.AddRight(t, " ", keepTok = true)
-            case _ => ()
-          }
-        }
-
         ctx.addPatchSet(builder.result(): _*)
       }
     }

diff --git a/scalafmt-tests/src/test/resources/rewrite/RedundantBraces-case.stat b/scalafmt-tests/src/test/resources/rewrite/RedundantBraces-case.stat
@@ -96,8 +96,8 @@ object a {
   }
 }
 >>>
-test does not parse
 object a {
   a match {
-    case a ifa =>
-               ^
+    case a if a =>
+  }
+}
diff --git a/scalafmt-tests/src/test/resources/rewrite/RedundantBraces.stat b/scalafmt-tests/src/test/resources/rewrite/RedundantBraces.stat
@@ -856,4 +856,4 @@ object Issue {
 2
 }op2 3
 >>>
-1 op12op2 3
+1 op1 2 op2 3
diff --git a/scalafmt-tests/src/test/resources/rewrite/RedundantParens.stat b/scalafmt-tests/src/test/resources/rewrite/RedundantParens.stat
@@ -290,8 +290,8 @@ object a {
   }
 }
 >>>
-test does not parse
 object a {
   a match {
-    case a ifa =>
-               ^
+    case a if a =>
+  }
+}