Pluggy incompatibility with pytest==3.7.0 when using pipenv

[benhowes]

When updating in pipenv today:

$> pipenv install
Pipfile.lock (bd627c) out of date, updating to (5f00e3)...
Locking [dev-packages] dependencies...

Warning: Your dependencies could not be resolved. You likely have a mismatch in your sub-dependencies.
  You can use $ pipenv install --skip-lock to bypass this mechanism, then run $ pipenv graph to inspect the situation.
  Hint: try $ pipenv lock --pre if it is a pre-release dependency.
Could not find a version that matches pluggy<0.7,>=0.5,>=0.7
Tried: 0.3.0, 0.3.0, 0.3.1, 0.3.1, 0.4.0, 0.4.0, 0.5.0, 0.5.1, 0.5.1, 0.5.2, 0.5.2, 0.6.0, 0.6.0, 0.6.0, 0.7.1, 0.7.1
There are incompatible versions in the resolved dependencies.

I cannot see a way in which pytest-cov directly depends on pluggy though?

[nicoddemus]

I'm not sure either, but pytest 3.7.0 has changed pluggy pinning from >=0.5,<0.7 to >=0.7 in case this helps finding the issue. Perhaps is some other dependency pinning pluggy?

[gaffney]

Same problem today; pytest itself installs fine but the tools that depend on pytest do not:

• pytest-cov - causes this issue
• pytest-mock - causes this issue
• pytest-xdist - causes this issue
• pytest-helpers-namespace - causes this issue

I do not understand this issue because pipenv install --dev --skip-lock && pipenv graph does not show conflicts. Maybe this is a pipenv bug... ?

[gzagatti]

I am having this same issue and I believe it is related with the issue in here. It has to do with pipenv lack of backtracking.

[benhowes]

@gzagatti appears to be correct, pypa/pipenv#2596 (comment) solved this problem for me.

[benhowes]

I'll close this because that confirms it's a pipenv problem, not pytest/pytest-cov