warn about bad values for BreakLinesMethod

Author: Brenton Bostick

CodeFormatter/Kernel/CodeFormatter.wl

@@ -420,6 +420,11 @@ Module[{
  tabWidth = OptionValue["TabWidth"];
 
  breakLinesMethod = OptionValue["BreakLinesMethod"];
+
+ If[!MemberQ[{"LineBreakerV1", "LineBreakerV2"}, breakLinesMethod],
+ Throw[Failure["UnrecognizedOptionValue", <| "BreakLinesMethod" -> breakLinesMethod |>]]
+ ];
+
  lineWidth = OptionValue["LineWidth"];
  safetyMargin = OptionValue["SafetyMargin"];