Potential dependency conflicts between ksfest and matplotlib

[NeolithEra]

Hi, as shown in the following full dependency graph of ksfest, ksfest requires matplotlib ==3.1.1, ksfest requires seaborn * (seaborn 0.10.0 will be installed, i.e., the newest version satisfying the version constraint), and directed dependency seaborn 0.10.0 transitively introduces matplotlib >=2.1.2.

Obviously, there are multiple version constraints set for matplotlib in this project. However, according to pip's “first found wins” installation strategy, matplotlib 3.1.1 (i.e., the newest version satisfying constraint ==3.1.1) is the actually installed version.

Although the first found package version matplotlib 3.1.1 just satisfies the later dependency constraint （matplotlib ==3.1.1), such installed version is very close to the upper bound of the version constraint of matplotlib specified by seaborn 0.10.0.

Once seaborn upgrades，its newest version will be installed, as ksfest does not specify the upper bound of version constraint for seaborn. Therefore, it will easily cause a dependency conflict (build failure), if the upgraded seaborn version introduces a higher version of matplotlib, violating its another version constraint ==3.1.1.

According to the release history of seaborn, it habitually upgrates Matplotlib in its recent releases. For instance, seaborn 0.9.1.rc0 upgrated Matplotlib’s constraint from >=1.4.3 to >=1.5.3, and seaborn 0.10.0.rc0 upgrated Matplotlib’s constraint from >=1.5.3 to >=2.1.2.

As such, it is a warm warning of a potential dependency conflict issue for ksfest.

Dependency tree

ksfest - 0.1.8
| +- click(install version:7.1.1 version range:>=7.0)
| +- matplotlib(install version:3.1.1 version range:==3.1.1)
| +- numpy(install version:1.18.2 version range:>=1.15)
| +- pandas(install version:1.0.3 version range:>=0.19)
| +- scipy(install version:1.2.3 version range:>=0.18)
| +- seaborn(install version:0.10.0 version range:*)
| | +- matplotlib(install version:3.1.1 version range:>=2.1.2)
| | +- numpy(install version:1.18.2 version range:>=1.13.3)
| | +- pandas(install version:1.0.3 version range:>=0.22.0)
| | +- scipy(install version:1.2.3 version range:>=1.0.1)
| +- tqdm(install version:4.45.0 version range:>=4.38.0)

Thanks for your help.
Best,
Neolith

[NeolithEra]

Suggested Solution

1. Loosen the version range of matplotlib to be >=3.1.1.
2. Remove your direct dependency matplotlib, and use the matplotlib transitively introduced by seaborn.
3. Change your direct dependency seaborn to be <=0.10.0.
   @oristides Which solution do you prefer, 1 ,2or 3?
   Please let me know your choice. May I pull a request to solve this issue?

[oristides]

Option 2