Re-read last imap_email_content email when no change

[isk0001y]

Proposed change

In the Bug #35975 it is stated an issue that the state changes to Unknown after some time. This is actually not dependent on time, but on arrival of emails. So basically if no email arrives, the code will not find any unread email at all and default to returning None out of the read_next() method. However, this now is obviously undesired behavior if people decide to keep the emails in the mailbox.

This basically restores the original intent of staying in the previous state by trying to return the last detected email, if no change of emails occur at all, but supports still the deleted email usecase, because in that case email would become None, and state would turn to None again.

I assume that this matches more the initial intent of this piece of code

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

There is another change, which is related to the python imap library. If you for example archive emails, the uid() method returns an empty list. Looks like it was initially expected to return None, but to prevent subscript exceptions in the following line, I treat this empty list also as None.

• This PR fixes or closes issue: fixes imap_email_content set to unknown after 30 seconds #35975
• This PR is related to issue: imap_email_content set to unknown after 30 seconds #35975
• Link to documentation pull request:

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[MartinHjelmare]

It would be good to add explicit return None in the read_next method at all places where the method can exit.

[isk0001y]

What is your proposal for reconnect case? It will also return None but theoretically it could be fixed in a better way. I am unsure what is the best way.

[MartinHjelmare]

For now just return None at all exit places so return value is more clear. We can improve more later.

[isk0001y]

The more I look at it, the more the method looks annoying...

[MartinHjelmare]

Good!