[New-bugs-announce] [issue25791] Raise an ImportWarning when __spec__.parent/__package__ isn't defined for a relative import

[Brett Cannon]

New submission from Brett Cannon:

When you do a relative import, __package__ is used to help resolve it, but if it isn't defined we fall back on using __name__ and __path__. We should probably consider raising an ImportWarning if __package__ isn't defined so that some day we can consider cleaning up __import__ and its call signature to be a bit more sane and drop the `globals` argument. It would also help people catch errors where they went overboard deleting attributes off a module.

We should probably even extend it to start using __spec__.parent and then falling back to __package__, and only after both are found missing do we raise the ImportWarning about needing to use __name__ and __path__. That way __import__ can simply start taking in the spec of the calling module to do all of its work instead of having to pass all of globals().

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components: Interpreter Core
messages: 255838
nosy: brett.cannon, eric.snow, ncoghlan
priority: low
severity: normal
stage: test needed
status: open
title: Raise an ImportWarning when __spec__.parent/__package__ isn't defined for a relative import
type: enhancement
versions: Python 3.6

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue25791>
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