drnim: tiny progress (#13882)

* drnim: tiny progress
* refactoring complete
* drnim: prove .ensures annotations
* Moved code around to avoid code duplication
* drnim: first implementation of the 'old' property
* drnim: be precise about the assignment statement
* first implementation of --assumeUnique
* progress on forall/exists handling

compiler/cmdlinehelper.nim

@@ -11,10 +11,24 @@
 
 import
   options, idents, nimconf, extccomp, commands, msgs,
-  lineinfos, modulegraphs, condsyms, os, pathutils
+  lineinfos, modulegraphs, condsyms, os, pathutils, parseopt
 
 from strutils import normalize
 
+proc prependCurDir*(f: AbsoluteFile): AbsoluteFile =
+  when defined(unix):
+    if os.isAbsolute(f.string): result = f
+    else: result = AbsoluteFile("./" & f.string)
+  else:
+    result = f
+
+proc addCmdPrefix*(result: var string, kind: CmdLineKind) =
+  # consider moving this to std/parseopt
+  case kind
+  of cmdLongOption: result.add "--"
+  of cmdShortOption: result.add "-"
+  of cmdArgument, cmdEnd: discard
+
 type
   NimProg* = ref object
     suggestMode*: bool