RedundantBraces: fix removing blocks

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

@@ -661,8 +661,7 @@ class RedundantBraces(implicit val ftoks: FormatTokens)
       // can allow if: no ".foo", no "with B", or has braces
       !b.parent.is[Term.Select] || t.templ.inits.lengthCompare(1) <= 0 ||
       t.templ.body.stats.nonEmpty || t.tokens.last.is[T.RightBrace]
-    case _: Term => true
-    case _ => false
+    case _ => isTreeSingleExpr(s)
   }
 
   private def okToRemoveBlockWithinApply(b: Term.Block)(implicit

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

@@ -761,3 +761,39 @@ runner.dialect = scala3
     // Write here your test ....
     // don't forget to remove `pending`
 }
+<<< def body as nested block 1
+object a {
+  def foo = {
+    { val len = firstColumn + syntax.length; (len, len) }
+  }
+}
+>>>
+object a {
+  def foo = {
+    val len = firstColumn + syntax.length; (len, len)
+  }
+}
+<<< def body as nested block 2
+object a {
+  def foo = {
+    { { val len = firstColumn + syntax.length; (len, len) } }
+  }
+}
+>>>
+object a {
+  def foo = {
+    val len = firstColumn + syntax.length; (len, len)
+  }
+}
+<<< def body as nested block 3
+object a {
+  def foo = {
+    { { { val len = firstColumn + syntax.length; (len, len) } } }
+  }
+}
+>>>
+object a {
+  def foo = {
+    val len = firstColumn + syntax.length; (len, len)
+  }
+}

scalafmt-tests/shared/src/test/scala/org/scalafmt/FormatTests.scala

@@ -154,7 +154,7 @@ class FormatTests extends FunSuite with CanRunTests with FormatAssertions {
     val explored = Debug.explored.get()
     logger.debug(s"Total explored: $explored")
     if (!onlyUnit && !onlyManual)
-      assertEquals(explored, 2519748, "total explored")
+      assertEquals(explored, 2520060, "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 :'(