Uncommenting adds an extra whitespace in some cases

[remisalmon]

Issue Report Checklist

• Searched the issues page for similar reports
• Read the relevant sections of the Spyder Troubleshooting Guide and followed its advice
• Reproduced the issue after updating with conda update spyder (or pip, if not using Anaconda)
• Could not reproduce inside jupyter qtconsole (if console-related)
• Tried basic troubleshooting (if a bug/error)
  • Restarted Spyder
  • Reset preferences with spyder --reset
  • Reinstalled the latest version of Anaconda
  • Tried the other applicable steps from the Troubleshooting Guide
• Completed the Problem Description, Steps to Reproduce and Version sections below

Problem Description

Commenting and uncommenting a line with an odd number of leading whitespace adds an extra space.

What steps reproduce the problem?

1. Type

x = [1,
     2,
     3]

2. Select all 3 lines, comment and uncomment
3. The code is now

x = [1,
      2,
      3]

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

The code after step 3 should be

x = [1,
     2,
     3]

If the number of leading whitespace is even, for ex:

xx = [1,
      2,
      3]

then there is no issue.

Versions

• Spyder version: 4.2.0
• Python version: 3.8.5
• Qt version: 5.9.7
• PyQt version: 5.9.2
• Operating System name/version: Linux 5.9.10

Dependencies

# Mandatory:
atomicwrites >=1.2.0            :  1.4.0 (OK)
chardet >=2.0.0                 :  3.0.4 (OK)
cloudpickle >=0.5.0             :  1.6.0 (OK)
diff_match_patch >=20181111     :  20200713 (OK)
intervaltree >=3.0.2            :  3.0.2 (OK)
IPython >=4.0                   :  7.19.0 (OK)
jedi =0.17.2                    :  0.17.2 (OK)
jsonschema >=3.2.0              :  3.2.0 (OK)
keyring >=17.0.0                :  21.5.0 (OK)
nbconvert >=4.0                 :  6.0.7 (OK)
numpydoc >=0.6.0                :  1.1.0 (OK)
parso =0.7.0                    :  0.7.0 (OK)
pexpect >=4.4.0                 :  4.8.0 (OK)
pickleshare >=0.4               :  0.7.5 (OK)
psutil >=5.3                    :  5.7.3 (OK)
pygments >=2.0                  :  2.7.2 (OK)
pylint >=1.0                    :  2.6.0 (OK)
pyls >=0.36.1;<1.0.0            :  0.36.1 (OK)
pyls_black >=0.4.6              :  0.4.6 (OK)
pyls_spyder >=0.1.1             :  0.2.1 (OK)
qdarkstyle >=2.8                :  2.8.1 (OK)
qtawesome >=0.5.7               :  1.0.1 (OK)
qtconsole >=4.7.7               :  5.0.1 (OK)
qtpy >=1.5.0                    :  1.9.0 (OK)
rtree >=0.8.3                   :  0.9.4 (OK)
setuptools >=39.0.0             :  50.3.1.post20201107 (OK)
sphinx >=0.6.6                  :  3.3.1 (OK)
spyder_kernels >=1.10.0;<1.11.0 :  1.10.0 (OK)
three_merge >=0.1.1             :  0.1.1 (OK)
watchdog >=0.10.3               :  0.10.4 (OK)
xdg >=0.26                      :  0.26 (OK)
zmq >=17                        :  20.0.0 (OK)

# Optional:
cython >=0.21                   :  None (NOK)
matplotlib >=2.0.0              :  None (NOK)
numpy >=1.7                     :  None (NOK)
pandas >=1.1.1                  :  None (NOK)
scipy >=0.17.0                  :  None (NOK)
sympy >=0.7.3                   :  None (NOK)

[steff456]

Hi @remisalmon,

I could reproduce this issue, we will fix it for our future version of spyder.

Thanks for reporting!

[Mark531]

Is there any chance for a fix soon? This bug persists in v5.0.0.

[remisalmon]

@Mark531 I have opened at PR at #14768.

[cg-mayrhofer]

Same here, this can be reproduced with tabs instead of whitespace as indent type. Toggle Comment adds a whitespace and when the line is indented, the space remains.
Using Spyder 5.3.3