Save `pdb` Line History Between Runs

Feature or enhancement

Proposal:

When using pdb, it is possible to use the arrow keys (up/down) to navigate through previous commands. However, commands between runs are not preserved (unlike in the REPL).

I would like commands to be preserved between runs. For me, the most common use case for this is setting a breakpoint in the same place. Currently, I do this with python -m pdb -c "break file.py:line" ....

I am not familiar with how the pdb is implemented, but I have used bdb in depth in the past. I assume that it is possible to do this in a similar way to the REPL history. There is a workaround available here: https://stackoverflow.com/a/35390866/.

Has this already been discussed elsewhere?

This is a minor feature, which does not need previous discussion elsewhere

Links to previous discussion of this feature:

No response

Start by tracing how pdb handles command history and compare it with the REPL history behavior; the issue points to bdb and the python -m pdb -c entry point. Confirm the intended persistence scope, then verify that commands entered in one debugging run are available in a later run without breaking arrow-key navigation or existing -c commands.