prompt-toolkit history now properly working with a persistent history file

Author: tleonhardt

cmd2/cmd2.py

@@ -413,6 +413,11 @@ def __init__(
         # Commands to exclude from the help menu and tab completion
         self.hidden_commands = ['eof', '_relative_run_script']
 
+        # Initialize history from a persistent history file (if present)
+        self.persistent_history_file = ''
+        self._persistent_history_length = persistent_history_length
+        self._initialize_history(persistent_history_file)
+
         # Initialize prompt-toolkit PromptSession
         self.history_adapter = Cmd2History(self)
         self.completer = Cmd2Completer(self)
@@ -421,11 +426,6 @@ def __init__(
             completer=self.completer,
         )
 
-        # Initialize history from a persistent history file (if present)
-        self.persistent_history_file = ''
-        self._persistent_history_length = persistent_history_length
-        self._initialize_history(persistent_history_file)
-
         # Commands to exclude from the history command
         self.exclude_from_history = ['eof', 'history']
 

cmd2/pt_utils.py

@@ -84,8 +84,18 @@ def __init__(self, cmd_app: 'Cmd') -> None:
 
     def load_history_strings(self) -> Iterable[str]:
         """Yield strings from cmd2's history to prompt_toolkit."""
-        for item in self.cmd_app.history:
-            yield item.statement.raw
+        last_item = None
+        for item in reversed(self.cmd_app.history):
+            if item.statement.raw != last_item:
+                yield item.statement.raw
+                last_item = item.statement.raw
+
+    def get_strings(self) -> list[str]:
+        """Get the strings from the history that are loaded so far."""
+        if not self._loaded:
+            self._loaded_strings = list(self.load_history_strings())
+            self._loaded = True
+        return super().get_strings()
 
     def store_string(self, string: str) -> None:
         """prompt_toolkit calls this when a line is accepted.

tests/test_history.py

@@ -978,9 +978,9 @@ def test_history_populates_pt(hist_file) -> None:
     # using the same rules
     pt_history = app.session.history.get_strings()
     assert len(pt_history) == 3
-    assert pt_history.get(1) == 'help'
-    assert pt_history.get(2) == 'shortcuts'
-    assert pt_history.get(3) == 'alias'
+    assert pt_history[0] == 'help'
+    assert pt_history[1] == 'shortcuts'
+    assert pt_history[2] == 'alias'
 
 
 #