TypeError: 'dict' object is not reversible in Python 3.7

[indranilo]

Description

What steps will reproduce the problem?

I had to reset my laptop, then installed pythion 3.7.9 and spyder. The first time I ran spyder from command prompt, I am stuck with this error.

Traceback

Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible
QBackingStore::endPaint() called with active painter; did you forget to destroy it or call QPainter::end() on it?
Traceback (most recent call last):
  File "c:\users\indranil ojha\appdata\local\programs\python\python37\lib\site-packages\spyder\plugins\editor\panels\scrollflag.py", line 218, in paintEvent
    for flag_type in reversed(dict_flag_lists):
TypeError: 'dict' object is not reversible

Versions

• Spyder version: 5.4.4 (pip)
• Python version: 3.7.9 64-bit
• Qt version: 5.15.2
• PyQt5 version: 5.15.9
• Operating System: Windows-10-10.0.22000-SP0

Dependencies

# Mandatory:
atomicwrites >=1.2.0                                                        :  1.4.1 (OK)
chardet >=2.0.0                                                             :  5.2.0 (OK)
cloudpickle >=0.5.0                                                         :  2.2.1 (OK)
cookiecutter >=1.6.0                                                        :  2.3.0 (OK)
diff_match_patch >=20181111                                                 :  20230430 (OK)
intervaltree >=3.0.2                                                        :  3.1.0 (OK)
IPython >=7.31.1,<9.0.0,!=8.8.0,!=8.9.0,!=8.10.0,!=8.11.0,!=8.12.0,!=8.12.1 :  7.34.0 (OK)
jedi >=0.17.2,<0.19.0                                                       :  0.18.2 (OK)
jellyfish >=0.7                                                             :  1.0.0 (OK)
jsonschema >=3.2.0                                                          :  4.17.3 (OK)
keyring >=17.0.0                                                            :  24.1.1 (OK)
nbconvert >=4.0                                                             :  7.6.0 (OK)
numpydoc >=0.6.0                                                            :  1.5.0 (OK)
paramiko >=2.4.0                                                            :  3.3.1 (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                                                                :  5.9.5 (OK)
pygments >=2.0                                                              :  2.16.1 (OK)
pylint >=2.5.0,<3.0                                                         :  2.17.5 (OK)
pylint_venv >=3.0.2                                                         :  3.0.2 (OK)
pyls_spyder >=0.4.0                                                         :  0.4.0 (OK)
pylsp >=1.7.4,<1.8.0                                                        :  1.7.4 (OK)
pylsp_black >=1.2.0,<3.0.0                                                  :  1.3.0 (OK)
qdarkstyle >=3.0.2,<3.2.0                                                   :  3.1 (OK)
qstylizer >=0.2.2                                                           :  0.2.2 (OK)
qtawesome >=1.2.1                                                           :  1.2.3 (OK)
qtconsole >=5.4.2,<5.5.0                                                    :  5.4.3 (OK)
qtpy >=2.1.0                                                                :  2.3.1 (OK)
rtree >=0.9.7                                                               :  1.0.1 (OK)
setuptools >=49.6.0                                                         :  68.0.0 (OK)
sphinx >=0.6.6                                                              :  5.3.0 (OK)
spyder_kernels >=2.4.4,<2.5.0                                               :  2.4.4 (OK)
textdistance >=4.2.0                                                        :  4.5.0 (OK)
three_merge >=0.1.1                                                         :  0.1.1 (OK)
watchdog >=0.10.3                                                           :  3.0.0 (OK)
zmq >=22.1.0                                                                :  25.1.1 (OK)

# Optional:
cython >=0.21                                                               :  None (NOK)
matplotlib >=3.0.0                                                          :  3.5.3 (OK)
numpy >=1.7                                                                 :  1.21.6 (OK)
pandas >=1.1.1                                                              :  1.3.5 (OK)
scipy >=0.17.0                                                              :  1.7.3 (OK)
sympy >=0.7.3                                                               :  None (NOK)

[ccordoba12]

Hey @indranilo, thanks a lot for reporting. It seems we broke compatibility with Python 3.7 in our latest version (5.4.4) because the ability to reverse dictionaries (which is causing the error you reported) was added in Python 3.8 (see here).

We'll fix this in a new, emergency version (5.4.5), to be released in the next couple of days. In the meantime, please downgrade to 5.4.3, which shouldn't have this problem.