Changed History to use OrderDict to support Python 3.6 in non-CPython…

… environments.

cmd2/cmd2.py

@@ -43,6 +43,7 @@
     InteractiveConsole,
 )
 from collections import (
+    OrderedDict,
     namedtuple,
 )
 from contextlib import (
@@ -4359,7 +4360,7 @@ def do_history(self, args: argparse.Namespace) -> Optional[bool]:
             for idx, hi in history.items():
                 self.poutput(hi.pr(idx, script=args.script, expanded=args.expanded, verbose=args.verbose))
 
-    def _get_history(self, args: argparse.Namespace) -> Dict[int, HistoryItem]:
+    def _get_history(self, args: argparse.Namespace) -> 'OrderedDict[int, HistoryItem]':
         """If an argument was supplied, then retrieve partial contents of the history; otherwise retrieve entire history.
 
         This function returns a dictionary with history items keyed by their 1-based index in ascending order.

cmd2/history.py

@@ -4,9 +4,11 @@
 """
 
 import re
+from collections import (
+    OrderedDict,
+)
 from typing import (
     Callable,
-    Dict,
     Optional,
     Union,
 )
@@ -173,7 +175,7 @@ def get(self, index: int) -> HistoryItem:
     #
     spanpattern = re.compile(r'^\s*(?P<start>-?[1-9]\d*)?(?P<separator>:|(\.{2,}))(?P<end>-?[1-9]\d*)?\s*$')
 
-    def span(self, span: str, include_persisted: bool = False) -> Dict[int, HistoryItem]:
+    def span(self, span: str, include_persisted: bool = False) -> 'OrderedDict[int, HistoryItem]':
         """Return a slice of the History list
 
         :param span: string containing an index or a slice
@@ -222,7 +224,7 @@ def span(self, span: str, include_persisted: bool = False) -> Dict[int, HistoryI
 
         return self._build_result_dictionary(start, end)
 
-    def str_search(self, search: str, include_persisted: bool = False) -> Dict[int, HistoryItem]:
+    def str_search(self, search: str, include_persisted: bool = False) -> 'OrderedDict[int, HistoryItem]':
         """Find history items which contain a given string
 
         :param search: the string to search for
@@ -241,7 +243,7 @@ def isin(history_item: HistoryItem) -> bool:
         start = 0 if include_persisted else self.session_start_index
         return self._build_result_dictionary(start, len(self), isin)
 
-    def regex_search(self, regex: str, include_persisted: bool = False) -> Dict[int, HistoryItem]:
+    def regex_search(self, regex: str, include_persisted: bool = False) -> 'OrderedDict[int, HistoryItem]':
         """Find history items which match a given regular expression
 
         :param regex: the regular expression to search for.
@@ -277,13 +279,13 @@ def truncate(self, max_length: int) -> None:
 
     def _build_result_dictionary(
         self, start: int, end: int, filter_func: Optional[Callable[[HistoryItem], bool]] = None
-    ) -> Dict[int, HistoryItem]:
+    ) -> 'OrderedDict[int, HistoryItem]':
         """
         Build history search results
         :param start: start index to search from
         :param end: end index to stop searching (exclusive)
         """
-        results: Dict[int, HistoryItem] = dict()
+        results: OrderedDict[int, HistoryItem] = OrderedDict()
         for index in range(start, end):
             if filter_func is None or filter_func(self[index]):
                 results[index + 1] = self[index]