Debugging capabilities?

[ElCondor1969]

Hi Jarrod.
Congratulations for your remarkable and very useful work.
Do you think it would ever be possible to debug a JetPascal project from Visual Studio Code or another editor?
I understand that there's some transpilling between the source code and the compiled code, and this could make it difficult.

Bye.

[jarroddavis68]

Thanks!
Absolutely. With JetPascal’s transpiler inserting proper #line directives into the generated C++, the debugger can actually map everything straight back to the original .pas file. When the C++ compiler builds with full debug symbols, the PDB ends up pointing to your Pascal source, not the generated C++.

So yes, stepping through Pascal, setting breakpoints in Pascal, and inspecting values while viewing the Pascal file is completely possible. The key is accurate #line mapping, and that’s already part of the plan for JetPascal. As long as the .pas file exists at the same path during debugging, VSCode or any other PDB-aware debugger can treat it as the real source.

Note: #line directives are already being inserted, which is why error messages point back to the correct locations in the .pas file. So technically you should be able to debug against the Pascal source right now, although I haven’t tested it yet. Better debugging support is definitely coming in future updates.

[ElCondor1969]

Great!
Thank you so much for your informations.

[jarroddavis68]

Here is an example of the bundled lldb debugging Pascal code, which will be in v0.2.0. In a future update I plan to have a jet debug command that will allow you to run the debugger from the jet cli.

[jarroddavis68]

This one is using DAP (Debug Adapter Protocol). It needs to use lldb-dap.exe, and it must be configured properly with a specific version of Python to work. It was a bit of a pain to extract from LLVM and configure to run standalone (a specific Python version is required, and the folders must be placed at the correct levels so it can find the needed files). The good news is that it will be bundled in 0.3.0 and should just work out of the box without any configuration or external dependencies. The TDebug class is using it with DAP (calling lldb-dap.exe), and it seems to work great.

[jarroddavis68]

I see this contains the binary as well, so in theory it should be working. See if it contains python with it. This maybe an issue. Does it mention python in the help?

[ElCondor1969]

Yes, you're right, the installation is also making me struggle because the latest versions don't have Python embedded and I can't find it anywhere...
I think I'll need to look for it slowly and take more time...

[ElCondor1969]

Returning to the excellent "CodeLLDB" extension and the issue of variable inspection in debug, I found a thread that might provide some useful information:

vadimcn/codelldb#65

Hope this helps.

[jarroddavis68]

Ok, thanks!