Validate button shows incomprehensible SyntaxError when the solution trips the timeout limit

[lahwaacz]

Operating system

Arch Linux

nbgrader --version

Python version 3.11.5 (main, Sep  2 2023, 14:16:33) [GCC 13.2.1 20230801]
nbgrader version 0.9.1

jupyterhub --version (if used with JupyterHub)

4.0.2

jupyter notebook --version

7.0.6

Expected behavior

Nbgrader should not display a SyntaxError when some internal operation fails.

Actual behavior

When a student tries to validate an assignment that gets stuck due to infinite loop, Nbgrader shows this error:

Validation failed
Cannot validate: SyntaxError: JSON.parse: unexpected character at line 1 column 1 of the JSON data

Steps to reproduce the behavior

Create an assignment with an infinite loop and click on "Validate":

while True:
    pass

[brichet]

On my side the test passes... and I don't think this is expected 😄

It should fail if the execution timeout.