The linenumber is not displayed properly

[ok97465]

Description

What steps will reproduce the problem?

Hello!

Thank you for your efforts to speed up the editor.
However, The line number does not seem to be displayed normally in the latest version.

Please check it out.
Have a good day.

Versions

• Spyder version: 5.3.0.dev0 15926c5
• Python version: 3.9.7
• Qt version: 5.12.9
• PyQt5 version: 5.12.3
• Operating System: Linux 5.4.0-97-generic

Dependencies

# Mandatory:
atomicwrites >=1.2.0                  :  1.4.0 (OK)
chardet >=2.0.0                       :  4.0.0 (OK)
cloudpickle >=0.5.0                   :  2.0.0 (OK)
cookiecutter >=1.6.0                  :  1.7.2 (OK)
diff_match_patch >=20181111           :  20200713 (OK)
intervaltree >=3.0.2                  :  3.1.0 (OK)
IPython >=7.6.0;<8.0.0                :  7.31.1 (OK)
jedi >=0.17.2;<0.19.0                 :  0.18.1 (OK)
jellyfish >=0.7                       :  0.8.9 (OK)
jsonschema >=3.2.0                    :  3.2.0 (OK)
keyring >=17.0.0                      :  23.4.0 (OK)
nbconvert >=4.0                       :  6.3.0 (OK)
numpydoc >=0.6.0                      :  1.2 (OK)
parso >=0.7.0;<0.9.0                  :  0.8.3 (OK)
pexpect >=4.4.0                       :  4.8.0 (OK)
pickleshare >=0.4                     :  0.7.5 (OK)
psutil >=5.3                          :  5.8.0 (OK)
pygments >=2.0                        :  2.10.0 (OK)
pylint >=2.5.0                        :  2.12.2 (OK)
pyls_spyder >=0.4.0                   :  0.4.0 (OK)
pylsp >=1.3.2;<1.4.0                  :  1.4.0.dev0 (OK)
pylsp_black >=1.0.0                   :  1.0.0 (OK)
qdarkstyle =3.0.2                     :  3.0.2 (OK)
qstylizer >=0.1.10                    :  0.1.10 (OK)
qtawesome >=1.0.2                     :  1.0.3 (OK)
qtconsole >=5.2.1;<5.3.0              :  5.2.1 (OK)
qtpy >=1.5.0                          :  1.11.2 (OK)
rtree >=0.9.7                         :  0.9.7 (OK)
setuptools >=49.6.0                   :  58.0.4 (OK)
sphinx >=0.6.6                        :  4.4.0 (OK)
spyder_kernels >=2.2.1;<2.3.0         :  2.3.0.dev0 (OK)
textdistance >=4.2.0                  :  4.2.1 (OK)
three_merge >=0.1.1                   :  0.1.1 (OK)
watchdog >=0.10.3                     :  2.1.6 (OK)
xdg >=0.26                            :  0.27 (OK)
zmq >=17                              :  22.3.0 (OK)

# Optional:
cython >=0.21                         :  0.29.25 (OK)
matplotlib >=2.0.0                    :  3.5.0 (OK)
numpy >=1.7                           :  1.20.3 (OK)
pandas >=1.1.1                        :  1.3.5 (OK)
scipy >=0.17.0                        :  1.7.3 (OK)
sympy >=0.7.3                         :  1.9 (OK)

# Spyder plugins:
spyder_okvim.spyder.plugin 0.0.1.dev0 :  0.0.1-dev0 (OK)

[ccordoba12]

Hey @ok97465, thanks for reporting! I can confirm this problem on Linux and I was about to report it.

@impact27, could you take a look at it? It seems the computations to determine line height are a bit off on Linux.

@dalthviz, could you post a screenshot of what do you see on Windows?

[dalthviz]

This is what I'm seeing on Windows (seems like the line numbers are aligned there):

[ccordoba12]

@dalthviz, could you put the cursor in a given line (not in the first ten) and upload another screenshot? I think the problem is with the current line.

[dalthviz]

[ccordoba12]

Thanks @dalthviz! So things on Windows are working just fine.

@steff456, could post a similar screenshot on macOS?

[impact27]

On mac:

[impact27]

If you zoom in and out, does it fix it?

[impact27]

The font size appears to be the same. I think the issue is with the line spacing:

[impact27]

You can check the height and leading by adding in LineNumberArea::draw_linenumbers below font.setWeight(font.Normal):

from qtpy.QtGui import QFontMetricsF
fm = QFontMetricsF(font)
print(fm.lineSpacing(), fm.height(), fm.leading())

On mac I get 12.796875 12.796875 0.0. Maybe the css sheet on linux adds 2px of leading to the editor?
There is a problem however that I can not find a way of adjusting the line spacing for QStaticText (see https://bugreports.qt.io/browse/QTBUG-3545).

Maybe using QTextDocument.drawContents would be more reliable? But this should be profiled.

[impact27]

Could you try: #17321

[ok97465]

from qtpy.QtGui import QFontMetricsF
fm = QFontMetricsF(font)
print(fm.lineSpacing(), fm.height(), fm.leading())

The result of code is 16.0, 17.0, -1.0.

[impact27]

The font is supposed to be the same. I tried to match the stylesheet as that might affect the line spacing.

[ok97465]

Could you try: #17321

I'm sorry but the result of #17321 is the same.

[impact27]

I'm sorry but the result of #17321 is the same.

Thanks for checking! What if you change the font? Maybe there is an issue with negative leading? Could you select a font without negative leading?

[ok97465]

You're right. Linenumber is working well when using some font. But It is not working when I use "JetBrains Mono", "Ubuntu mono", "Fira Mono".

[impact27]

From the picture above, the baseline to baseline disctance of the line number is 32px (=2 * 16) while the baseline to baseline distance of the text is 34px ( = 2 * 17). So it looks like the editor is somehow not respecting the leading of the font? One solution could be to remove the optimisation when the leading is negative. The editor will be slower but at least the line numbers will be aligned.

[impact27]

#17321 should work now (but slower when the leading is not 0)