Pipenv: pytest-cov . के साथ pytest स्थापित करते समय निर्भरता का समाधान नहीं किया जा सका

मुदे का विवरण

मैं pytest और pytest-cov स्थापित नहीं कर सकता क्योंकि यह निर्भरता के बारे में शिकायत करता है कि इसका समाधान नहीं किया जा रहा है।

दोहराने और आउटपुट करने के लिए कदम

माई पिपफाइल

[[source]]
url = "https://pypi.org/simple"
verify_ssl = true
name = "pypi"

[packages]
pytest = "*"
pytest-cov = "*"

[dev-packages]

[requires]
python_version = "3.6"

 $ pipenv install
Pipfile.lock (ca72e7) out of date, updating to (4ccbf7)...
Locking [dev-packages] dependencies...
Locking [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.

मैं तब एक करता हूं:

$ pipenv install --skip-lock
$ pipenv graph
pytest-cov==2.5.1
  - coverage [required: >=3.7.1, installed: 4.5.1]
  - pytest [required: >=2.6.0, installed: 3.7.0]
    - atomicwrites [required: >=1.0, installed: 1.1.5]
    - attrs [required: >=17.4.0, installed: 18.1.0]
    - more-itertools [required: >=4.0.0, installed: 4.3.0]
      - six [required: >=1.0.0,<2.0.0, installed: 1.11.0]
    - pluggy [required: >=0.7, installed: 0.7.1]
    - py [required: >=1.5.0, installed: 1.5.4]
    - setuptools [required: Any, installed: 40.0.0]
    - six [required: >=1.10.0, installed: 1.11.0]

निर्भरता ठीक दिखती है।