Adding applications to file associations is broken on Windows due to unescaped backslashes

Description

What steps will reproduce the problem?

1. From a clean config, open the File Associations tab of the Files prefs pane
2. Add any extension (e.g. .txt) to enable the “add” option for external programs
3. Click the add button, and the resulting error appears

I haven’t investigated the relevant code thoroughly, but it appears to be due to unescaped backslashes in Windows file paths combined with use of eval. I’d suggest simply using standard forward slashes instead (using replace to convert them before parsing if necessary) since they are equally accepted on Windows as backslashes.

Also, even after I dismiss the error, my cursor remains stuck in the “hourglass” mode that was triggered with the failed launch of the file open dialog.

Traceback

  File "C:\Miniconda3\envs\spyder-4\lib\site-packages\spyder\plugins\explorer\widgets\fileassociations.py", line 496, in add_application
    self._dlg_applications = ApplicationsDialog(self)
  File "C:\Miniconda3\envs\spyder-4\lib\site-packages\spyder\plugins\explorer\widgets\fileassociations.py", line 145, in __init__
    self.setup()
  File "C:\Miniconda3\envs\spyder-4\lib\site-packages\spyder\plugins\explorer\widgets\fileassociations.py", line 152, in setup
    apps = get_installed_applications()
  File "C:\Miniconda3\envs\spyder-4\lib\site-packages\spyder\utils\programs.py", line 493, in get_installed_applications
    apps = _get_win_applications()
  File "C:\Miniconda3\envs\spyder-4\lib\site-packages\spyder\utils\programs.py", line 362, in _get_win_applications
    expanded_fpath = literal_eval(expanded_fpath)
  File "C:\Miniconda3\envs\spyder-4\lib\ast.py", line 46, in literal_eval
    node_or_string = parse(node_or_string, mode='eval')
  File "C:\Miniconda3\envs\spyder-4\lib\ast.py", line 35, in parse
    return compile(source, filename, mode, PyCF_ONLY_AST)
  File "<unknown>", line 1
    c:\program files (x86)\malwarebytes' anti-malware\mbam.exe
     ^
SyntaxError: invalid syntax

Versions

• Spyder version: 4.0.0rc1
• Python version: 3.7.5
• Qt version: 5.9.6
• PyQt5 version: 5.9.2
• Operating System: Windows 8.1

Dependencies

cloudpickle >=0.5.0          :  0.7.0 (OK)
pygments >=2.0               :  2.3.1 (OK)
qtconsole >=4.5.5            :  4.5.5 (OK)
nbconvert >=4.0              :  5.4.0 (OK)
sphinx >=0.6.6               :  1.8.4 (OK)
pylint >=0.25                :  2.2.2 (OK)
psutil >=0.3                 :  5.6.3 (OK)
qtawesome >=0.5.7            :  0.6.0 (OK)
qtpy >=1.5.0                 :  1.9.0 (OK)
pickleshare >=0.4            :  0.7.5 (OK)
zmq >=17                     :  17.1.2 (OK)
chardet >=2.0.0              :  3.0.4 (OK)
numpydoc >=0.6.0             :  0.8.0 (OK)
spyder_kernels >=1.7.0;<2.0.0:  1.7.0 (OK)
qdarkstyle >=2.7             :  2.7 (OK)
atomicwrites >=1.2.0         :  1.3.0 (OK)
diff_match_patch >=20181111  :  20181111 (OK)
watchdog                     :  None (OK)
keyring                      :  None (OK)
pexpect >=4.4.0              :  4.7.0 (OK)
pympler                      :  None (OK)
sympy >=0.7.3                :  1.3 (OK)
cython >=0.21                :  0.29.4 (OK)
IPython >=4.0                :  7.2.0 (OK)
matplotlib >=2.0.0           :  3.0.2 (OK)
pandas >=0.13.1              :  0.24.2 (OK)
numpy >=1.7                  :  1.15.4 (OK)
scipy >=0.17.0               :  1.2.0 (OK)
pyls >=0.29.3;<0.30.0        :  0.29.3 (OK)
rtree >=0.8.3                :  0.8.3 (OK)

[CAM-Gerlach]

@ccordoba12 Sure, I’ll add it to my list. As you say its not at all critical and it should be a quick fix and test for me to do so I’ll try to get to it perhaps after the Spyder 4.0 release. Thanks.

[ccordoba12]

If you found a fix, please submit a pull request for that, along with tests. If not, we’ll try to fix that when more important things are solved.