Debugging inside Jinja templates using pdb/ipdb

Mon, 04 Mar 2024 14:42:00 +0100

I’m working on a static reporting tool using the Jinja2 templating engine for Python.

I was trying to figure out a way to enter into the Jinja templating code with the pdb/ipdb commandline debugger.

I tried creating an .ipdbrc file in my local directory with the line:

path/to/template.html:<lineno>

… but that didn’t work.

What worked was to figure out the line that says :

return self.environment.concat(self.root_render_func(ctx))

… inside the the jinja codebase, and put a breakpoint on that (which for me was on line 1299, but might vary depending on version):

Jinja on Living Systems_