Latest IPython (8.1.0) doesn't support stepInto correctly with 1.5.1

[rchiodo]

Environment data

• debugpy version: 1.5.1
• OS and version: Windows 10
• Python version (& distribution if applicable, e.g. Anaconda): 3.10
• Using VS Code or Visual Studio: VS code

Actual behavior

Create a notebook with cell with a number of lines:

Put a breakpoint on the first line
Debug the cell
Step into

Step into gets stuck on the first line.

Run by line (another way we support debugging)

also behaves strangely. It can't step through the function.

Expected behavior

Stepping works

@fabioz I believe this was caused by your recent change to IPython? Do we need a newer version of Debugpy to handle that change?

[rchiodo]

Seems like if there's a breakpoint on the first line, every step into will alternate between that line and the actual line to step into.

[int19h]

It sounds like #851 was the fix for this?

[rchiodo]

I don't think so? At least I cloned debugpy and copied it into my site packages. I'm still getting the problem.

[rchiodo]

Maybe that didn't work. It looks like I don't have the latest changes for some reason.

[rchiodo]

No even with the latest changes, still repros.

[fabioz]

No even with the latest changes, still repros.

This happens because in Python 3.10 there is always a line event at line 1 and Python itself is making that line event due to the way it's compiled now.

It seems my fix wasn't complete then... This will need another fix in IPython so that besides the new co_name the co_lnotab is also redone so that this spurious line event isn't done.

[fabioz]

Actually, this didn't need a change in IPython again (the debugger already had something to ignore spurious lines like this for <module>, so, I've extended it to handle the new <cell pattern for co_name in IPython).