fix compiler's and tools' use of parseopt

Author: ZoomRmc

compiler/nim.nim

@@ -48,7 +48,8 @@ proc nimbleLockExists(config: ConfigRef): bool =
   return fileExists(pd.string / nimbleLock)
 
 proc processCmdLine(pass: TCmdLinePass, cmd: string; config: ConfigRef) =
-  var p = parseopt.initOptParser(cmd)
+  var p = if cmd.len == 0: parseopt.initOptParser()
+          else: parseopt.initOptParser(cmd)
   var argsCount = 0
 
   config.commandLine.setLen 0

drnim/drnim.nim

@@ -1208,7 +1208,8 @@ proc mainCommand(graph: ModuleGraph) =
     genSuccessX(graph.config)
 
 proc processCmdLine(pass: TCmdLinePass, cmd: string; config: ConfigRef) =
-  var p = parseopt.initOptParser(cmd)
+  var p = if cmd.len == 0: parseopt.initOptParser()
+          else: parseopt.initOptParser(cmd)
   var argsCount = 1
 
   config.commandLine.setLen 0

nimsuggest/nimsuggest.nim

@@ -668,7 +668,8 @@ proc mainCommand(graph: ModuleGraph) =
   close(results)
 
 proc processCmdLine*(pass: TCmdLinePass, cmd: string; conf: ConfigRef) =
-  var p = parseopt.initOptParser(cmd)
+  var p = if cmd.len == 0: parseopt.initOptParser()
+          else: parseopt.initOptParser(cmd)
   var findProject = false
   while true:
     parseopt.next(p)