NimScript: --define works as expected

compiler/scriptconfig.nim

@@ -140,4 +140,7 @@ proc runNimScript*(scriptName: string) =
   # ensure we load 'system.nim' again for the real non-config stuff!
   resetAllModulesHard()
   vm.globalCtx = nil
-  initDefines()
+  # do not remove the defined symbols
+  #initDefines()
+  undefSymbol("nimscript")
+  undefSymbol("nimconfig")

tests/newconfig/tfoo.nim

@@ -4,4 +4,7 @@ discard """
   msg: '''[NimScript] exec: gcc -v'''
 """
 
+when not defined(definedefine):
+  {.fatal: "wrong nim script configuration".}
+
 echo "hello world!"

tests/newconfig/tfoo.nims

@@ -10,5 +10,6 @@ task listDirs, "lists every subdirectory":
     echo "DIR ", x
 
 task default, "default target":
+  --define: definedefine
   setCommand "c"