A Python background process stays opened after closing Spyder in master

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• Completed the Problem Description, Steps to Reproduce and Version sections below

Problem Description

After opening Spyder in master with the bootstrap.py or from the Anaconda navigator and closing it, a Python process remains opened in Windows. Introspection becomes broken by this until I close these background processes and restart Spyder. So this is probably related with the problems I reported in Issue #7726.

Note that this is not occurring with the 3.x branch.

What steps reproduce the problem?

1. Open Spyder
2. Close Spyder

What is the expected output? What do you see instead?

All Python processes started by Spyder should be closed

Versions

• Spyder version: Spyder 4.0.0.dev0 https://github.com/spyder-ide/spyder/commit/3465e77f077a346b71dfdf85d5f7eea98e64162b
• Python version: Python 3.6.5 64bits
• Qt version: Qt 5.9.3
• PyQt version: PyQt5 5.9.2
• Operating System name/version: Windows 10

Dependencies

pyflakes >=0.6.0  :  1.6.0 (OK)
pycodestyle >=2.3 :  2.3.1 (OK)
pygments >=2.0    :  2.2.0 (OK)
sphinx >=0.6.6    :  1.7.1 (OK)
rope >=0.9.4      :  0.10.7 (OK)
jedi >=0.11.0     :  0.12.1 (OK)
nbconvert >=4.0   :  5.3.1 (OK)
pandas >=0.13.1   :  0.22.0 (OK)
numpy >=1.7       :  1.13.0 (OK)
sympy >=0.7.3     :  1.1.1 (OK)
cython >=0.21     :  0.27.3 (OK)
qtconsole >=4.2.0 :  4.3.1 (OK)
IPython >=4.0     :  6.2.1 (OK)
matplotlib >=2.0.0:  2.2.0 (OK)
pylint >=0.25     :  1.8.3 (OK)

[CAM-Gerlach]

I have been able to, although it doesn’t always make completion stop working at least in my limited testing.

[ccordoba12]

I indeed have had 3 processes stick around indefinitely each time after Spyder crashes

For the record, this is being worked on in PR #10111.