Fail on conflicting dependencies but not circular dependencies

[jaraco]

I'd like to use pipdeptree to detect conflicting dependencies - those that will cause problems with pkg_resources when imported or are otherwise not meeting their declared requirements. For that, this tool provides --warn fail. However, this option also causes the tool to fail on circular dependencies, which happens as a matter of course for a project that requires jaraco.text or jaraco.collections (as they depend on each other).

Probably pipdeptree should take --on-circular and --on-conflicting parameters, each accepting pass, fail, or warn.