change mimedb stroe stringtable to orderedtable (#18065)

* change mimedb stroe stringtable to orderedtable

* Update lib/pure/mimetypes.nim

Co-authored-by: Andreas Rumpf <rumpf_a@web.de>

lib/pure/mimetypes.nim

@@ -26,12 +26,12 @@ runnableExamples:
   doAssert m.getMimetype("fakext") == "text/fakelang"
   doAssert m.getMimetype("FaKeXT") == "text/fakelang"
 
-import strtabs
+import tables
 from strutils import startsWith, toLowerAscii, strip
 
 type
   MimeDB* = object
-    mimes: StringTableRef
+    mimes: OrderedTableRef[string, string]
 
 const mimes* = {
   "123": "application/vnd.lotus-1-2-3",
@@ -1903,7 +1903,8 @@ const mimes* = {
 func newMimetypes*(): MimeDB =
   ## Creates a new Mimetypes database. The database will contain the most
   ## common mimetypes.
-  result.mimes = mimes.newStringTable()
+  {.cast(noSideEffect).}:
+    result.mimes = mimes.newOrderedTable()
 
 func getMimetype*(mimedb: MimeDB, ext: string, default = "text/plain"): string =
   ## Gets mimetype which corresponds to `ext`. Returns `default` if `ext`

tests/stdlib/tmimetypes.nim

@@ -6,6 +6,7 @@ import std/mimetypes
 template main() =
   var m = newMimetypes()
   doAssert m.getMimetype("mp4") == "video/mp4"
+  doAssert m.getExt("application/json") == "json"
   # see also `runnableExamples`.
   # xxx we should have a way to avoid duplicating code between runnableExamples and tests