How do you debug Mako templates?

Question

So far I\'ve found it impossible to produce usable tracebacks when Mako templates aren\'t coded correctly.

Is there any way to debug templates besides iterating for ever

Answer 1

Using flask_mako, I find it's easier to skip over the TemplateError generation and just pass up the exception. I.e. in flask_mako.py, comment out the part that makes the TemplateError and just do a raise:

def _render(template, context, app):
 """Renders the template and fires the signal"""
app.update_template_context(context)
try:
    rv = template.render(**context)
    template_rendered.send(app, template=template, context=context)
    return rv
except:
    #translated = TemplateError(template)                                                                                                                 
    #raise translated                                                                                                                                     
    raise

}

Then you'll see a regular python exception that caused the problem along with line numbers in the template.