Test: Debug Cell in Jupyter notebooks

[DavidKutu]

Refs: microsoft/vscode-jupyter#1652

• macOS @tanhakabir
• linux @joaomoreno
• windows @joyceerhl

Complexity: 3

Authors: @roblourens, @DavidKutu

Create Issue

Create Issue

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Setup

• Use VS Code Insiders and the latest jupyter and python extensions
• Make sure that you have python 3.7 or greater installed and on your path as python3 or python
• Set up a python virtualenv:

mkdir jupyter-dbg
cd jupyter-dbg
python3 -m venv ipykernel-env

• Activate the virtual environment

Mac/Linux:

source ipykernel-env/bin/activate

Windows:

ipykernel-env\Scripts\activate.bat

• Install the latest version of ipykernel in the virtual environment, which has debugging support

pip install ipykernel --pre
python3 -m ipykernel install --user

• Open a .ipynb notebook file (You can use this one if you need one)
• Pick the kernel from your virtual env
• Set "jupyter.logging.level": "verbose"

Testing

• Set a breakpoint on the cell you want to test
• Click Debug Cell under the Run button, you should hit the breakpoint and start a normal debugging session
  
• Try stepping into other cells, other python files, and other python packages as usual
• Finishing the cell should stop debugging
• Interrupting or Restarting the kernel should also stop Debugging
• While debugging, the run by line button should be disabled
• You should never get a temp file opened that reads: Could not load source ...

More Testing

• Check on the panel, that Jupyter: Variables gets updated after each step

Filing issues

File issues on the jupyter repo using the link above. Include the log from the Jupyter output channel

Known Issues

• Can't check for ipykernel 6 on remote (Can't check for ipykernel 6 on remote kernel  vscode-jupyter#7576)
• If while debugging, you change a cell that was already ran, then step into it, we stop in it. We should open a file that stops on the actual code in the kernel (Show source for changed or deleted cells vscode-jupyter#7532)
• The restart button does not work

[joaomoreno]

I'm getting this, in the setup phase:

$ pip install ipykernel --pre
Collecting ipykernel
  Using cached https://files.pythonhosted.org/packages/d5/bd/6f983d5075fcb7f2c4e03846b9f922fbc81fc0bedb8c561e70ebd2640ee4/ipykernel-6.0.0a0-py3-none-any.whl
Collecting debugpy>=1.0.0 (from ipykernel)
  Using cached https://files.pythonhosted.org/packages/76/37/98d4867a68820592aed879cc20246c5e0165e127d86452b57119f3574cec/debugpy-1.4.3-cp36-cp36m-manylinux_2_5_x86_64.manylinux1_x86_64.manylinux_2_12_x86_64.manylinux2010_x86_64.whl
Collecting tornado>=4.2 (from ipykernel)
  Using cached https://files.pythonhosted.org/packages/01/d1/8750ad20cbcefb499bb8b405e243f83c2c89f78d139e6f8c8d800640f554/tornado-6.1-cp36-cp36m-manylinux1_x86_64.whl
Collecting ipython>=7.21.0 (from ipykernel)
  Could not find a version that satisfies the requirement ipython>=7.21.0 (from ipykernel) (from versions: 0.10, 0.10.1, 0.10.2, 0.11, 0.12, 0.12.1, 0.13, 0.13.1, 0.13.2, 1.0.0, 1.1.0, 1.2.0, 1.2.1, 2.0.0, 2.1.0, 2.2.0, 2.3.0, 2.3.1, 2.4.0, 2.4.1, 3.0.0, 3.1.0, 3.2.0, 3.2.1, 3.2.2, 3.2.3, 4.0.0b1, 4.0.0, 4.0.1, 4.0.2, 4.0.3, 4.1.0rc1, 4.1.0rc2, 4.1.0, 4.1.1, 4.1.2, 4.2.0, 4.2.1, 5.0.0b1, 5.0.0b2, 5.0.0b3, 5.0.0b4, 5.0.0rc1, 5.0.0, 5.1.0, 5.2.0, 5.2.1, 5.2.2, 5.3.0, 5.4.0, 5.4.1, 5.5.0, 5.6.0, 5.7.0, 5.8.0, 5.9.0, 5.10.0, 6.0.0rc1, 6.0.0, 6.1.0, 6.2.0, 6.2.1, 6.3.0, 6.3.1, 6.4.0, 6.5.0, 7.0.0b1, 7.0.0rc1, 7.0.0, 7.0.1, 7.1.0, 7.1.1, 7.2.0, 7.3.0, 7.4.0, 7.5.0, 7.6.0, 7.6.1, 7.7.0, 7.8.0, 7.9.0, 7.10.0, 7.10.1, 7.10.2, 7.11.0, 7.11.1, 7.12.0, 7.13.0, 7.14.0, 7.15.0, 7.16.0, 7.16.1)
No matching distribution found for ipython>=7.21.0 (from ipykernel)

Didn't manage to unblock myself from here. Let me know how I can proceed.

[joaomoreno]

@DavidKutu suggested:

could you try removing the --pre?

Doing so gives me an unsupported version of ipykernel, so I'm stuck again:

Successfully installed ipykernel-5.5.5

[joaomoreno]

Also, nitpicking: why do we go through great lengths to make sure we use virtual environments, but then python3 -m ipykernel install --user ends up putting something on my user's ~/.local folder? Seems strange to me.

[joaomoreno]

Managed to unblock myself: I was on Ubuntu 18.04 and that somehow was causing the issue. On Ubuntu 20.04, I successfully installed ipykernel 6.4.1.