• I have searched the issues of this repo and believe that this is not a duplicate.

(However, it is related to #436).

Issue

In the dark, old world of Python packaging, sub-dependencies are handled very poorly. If I recall correctly, pip will happily install a sub-dependency despite conflicting versions being specified by two direct dependencies... in fact I think which version it ends up installing depends on the order in requirements.txt. Yuck! Only very recently has it even started issuing a warning for cases like this.

In contrast, poetry does this right. It computes the entire dependency tree and will complain if there are conflicts anywhere in the tree.

But... many packages out there are not specifying their dependencies properly. Even if they are, there's always the possibility that their specified dependencies are a tighter range than they strictly need to be.

Is there a way to tell Poetry to force a specific version (or version) range of a dependency in cases like this — or in other words, to ignore a dependency specification of another dependency somewhere in the tree? If not, should there be?