`create_os_window()` calls `get_window_content_scale()` without initializing the `xscale` and `yscale` variables. Instead of initializing them everywhere, where this function is called, just do it once in the function itself.
Found with the Clang Static Analyzer.
Pillow wheel currently not available for python 3.9. So tries to install
from source and fails on missing zlib. So install zlib in brew and make
it available via PKG_CONFIG_PATH. Apparently, this wont be necessary
after Pillow 8, but who knows.
When selecting text by dragging upwards, the "end" of the selection is above the "start". This causes the `selection_has_screen_line()` to never return `true` in this case.
In practice this bug causes the selection to not be cleared when the screen contents under the selection change if it was made by dragging upwards.
On the initial commit of this feature, IPs were just matched with a
very simple regex that prioritised simplicity/readability over
accuracy.
This commit adds a postprocessor for ip matches that makes use of
Python's `ipaddress` in the standard library to validate all the IP
matches.
This way we don't need huge and complex regex patterns to match _and_
validate the IPs, and we can just use `ipaddress` to abstract us from
implementing all the validation logic into the regex pattern.
Without this fix the file with the list of notifications looks like this:
```
0.19.0,1601899026.4373078,<built-in method count of Notification object at 0x7f8c582193b0>
```
which ends up notifying about a new version all the time.
There was a warning when the CI executed the "macOS Brew" job:
```
DEPRECATION: Python 2.7 will reach the end of its life on January 1st, 2020. Please upgrade your Python as Python 2.7 won't be maintained after that date. A future version of pip will drop support for Python 2.7. More details about Python 2 support in pip, can be found at https://pip.pypa.io/en/latest/development/release-process/#python-2-support
```
To fix this, use pip3 instead of pip.
The new User Notifications Framework is only available on macOS 10.14 and above, while the old NSUserNotification API is deprecated in macOS 11 (Big Sur) and will probably be removed in the future.
This commit compiles a simple test program to see if the Framework is available and then uses either the new or the old API.
