Attach the PyDev interactive debugger to Python code running in PyXLL

Question

(In Windows 10, I have installed ...\AppData\Local\Enthought\Canopy that includes Python 2.7, and another ...\AppData\Local\Programs\Python\Python35 that includes Python 3.5. %PATH points to Canopy)

I want to make "attaching the PyDev interactive debugger to Python code running in PyXLL" work by following this link and this link.

So I have done the following:

1. saved eclipse_debug.py in the folder ...\AppData\Local\Enthought\Canopy\User\Lib\site-packages\pyxll\examples\, and made pyxll.cfg include eclipse_debug.py

2. added eclipse/plugins/org.python.pydev_4.5.4.201601292234/pysrc to %PATH (echo %PATH does show this path, whereas echo %PYTHONPATH% still returns %PYTHONPATH% in a command prompt)

3. added import pydevd;pydevd.settrace() to the hello function, which worked before in Excel (hello("abc") did return Hello, abc).

4. reloaded PyXll in Excel

However, as a result,

1. hello function does not work anymore

2. there is no new menu item as promised by This module adds an Excel menu item to attach to the PyDev debugger, and also an Excel macro so that this script can be run outside of Excel and call PyXLL to attach to the PyDev debugger. Therefore, I don't know how to debug.

Could anyone help?

PS: my quess is that pvdevd is not well inserted in the environment, because when I type import in the code, pydevd is not automatically suggested as packages such as numpy or numbers. But I am really confused with controlling PYTHONPATH or PATH inside Eclipse.

Edit 1:

I have set PYTHONPATH in the control panel of Windows to be ...eclipse/plugins/org.python.pydev_4.5.4.201601292234/pysrc. As a result, echo %PYTHONPATH% still returns this path in a command prompt. And the pydevd is auto-completing in eclipse.

With the following code, without using eclipse_debug.py, and after launching debug server, the execution breaks just after the line of settrace:

from pyxll import xl_func
@xl_func("string name: string")
def hello(name):
    import pydevd;pydevd.settrace()
    return "Hello, %s" % name

Now, I want to follow the way of eclipse_debug.py. I have done the following:

1) erase PYTHONPATH in the control panel of Windows (so, I want to rely on eclipse_debug.py to find the path)

2) modify only the first line of eclipse_debug.py to be eclipse_roots = [r"C:\my_path_to\eclipse"].

3) add eclipse_debug.py to pyxll.cfg

4) use the following code to define the function hello:

from pyxll import xl_func
@xl_func("string name: string")
def hello(name):
    return "Hello, %s" % name

5) launch debug server of eclipse, and then launch Excel, and then reload PyXLL

However, no menu item about debug appears in Excel, although the hello function works in Excel. Is there something wrong about my approach?

Answer 1

Rather than modifying the PYTHONPATH or PATH at the environment level, simply do import sys;sys.path.add(r'< full path to>eclipse/plugins/org.python.pydev_4.5.4.201601292234/pysrc') above the import pydevd;pydevd.settrace()

So you should end up with:

import sys
sys.path.add(r'< full path to>eclipse/plugins/org.python.pydev_4.5.4.201601292234/pysrc')
import pydevd
pydevd.settrace()

To answer some of your related issues:

• Python (AFAIK) does not ever look in PATH for python modules. That is what PYTHONPATH is for. At start-up Python will set sys.path to the contents of PYTHONPATH + any other settings.
• The pydevd not auto-completing was most likely because you PyDev does not know about the modifications you made or intended to make to PYTHONPATH. You can tell PyDev by modifying the interpreter settings.
• The eclipse_debug.py is intended to ease the connection to the debugger. You should use the eclipse_debug.py method or the above method. However if you use eclipse_debug.py you must update the paths near the top of the file.