Simplified formatting for `deppy.NotSatisfiable` error

[m1kola]

Today deppy.NotSatisfiable is being formated in a not very human friendly way: it is challenging to understand what exactly went wrong from the error message.

We need to explore error formatting options which:

• Describes in natural language what went wrong
• Does not include the description of the whole problem. Deppy (gini) already produces a minimised list of assumptions which together caused unsat - we need to keep this property.

This probably should be plugable.

[m1kola]

I really like how pip does it. Few examples I found on the internet (probably from different pip versions):

pandas-profiling 3.6.1 requires numpy<1.24,>=1.16.0, but you have numpy 1.24.1 which is incompatible.
numba 0.54.1 requires numpy<1.21,>=1.17, but you have numpy 1.24.1 which is incompatible.

Or more complex one:

The conflict is caused by:
    The user requested six==1.10.0
    bcrypt 3.2.0 depends on six>=1.4.1
    cvxpy 1.0.25 depends on six
    django-anymail 0.5 depends on six
    django-compat 1.0.15 depends on six>=1.10.0
    django-extensions 2.2.1 depends on six>=1.2
    drf-yasg 1.16.1 depends on six>=1.10.0
    fake-factory 0.6.0 depends on six
    google-api-core 1.26.0 depends on six>=1.13.0

[m1kola]

This repo with examples on how to format errors might be useful: https://github.com/perdasilva/deconflictor.

[m1kola]

I updated the description of the issue beucase it was initially not factually true: I origianlly said that deppy.NotSatisfiable contains description of the whole problem. It is not true: Deppy (thanks to Gini) only produces a minimised list of assumptions which together caused unsat.

I think readability of deppy.NotSatisfiable will be greatly influenced by the approach taken to building the constraints on the users side (e.g. IDs used, and how dependencies structured).

[joelanford]

IDs used

I think we have overlooked this particular aspect as well. We should define a standard for how to structure IDs and perhaps add a package (not sure where) to help users build IDs that will be easier to reason about.

[github-actions]

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[github-actions]

This issue has become stale because it has been open 60 days with no activity. The maintainers of this repo will remove this label during issue triage or it will be removed automatically after an update. Adding the lifecycle/frozen label will cause this issue to ignore lifecycle events.