nimsuggest: special rule for 'of' completion in case statements

nimsuggest/tests/tcase.nim

@@ -0,0 +1,17 @@
+
+type
+  MyEnum = enum
+    nkIf, nkElse, nkElif
+
+proc test(a: MyEnum) =
+  case a
+  of nkElse: discard
+  of #[!]#
+
+discard """
+$nimsuggest --tester $file
+>sug $1
+sug;;skEnumField;;nkElse;;MyEnum;;$file;;4;;10;;"";;100;;None
+sug;;skEnumField;;nkElif;;MyEnum;;$file;;4;;18;;"";;100;;None
+sug;;skEnumField;;nkIf;;MyEnum;;$file;;4;;4;;"";;100;;None
+"""