Disallow freeze format with pip list --outdated

[Mr-Pepe]

Resolves #9789 by raising an error if pip list --outdated is used in combination with --format=freeze

[informatik01]

A few days ago I updated pip to version 22.3 and today, when executing pip list --outdated --format=freeze, received an error:

ERROR: List format 'freeze' can not be used with the --outdated option.

Already wanted to open an issue, but then I found this page. At least now I know it was done on purpose.

Suggestion

It would be really nice if you update the related documentation both online and for the pip command help info (pip list --help) to reflect these latest changes.

Currently the documentation still mentions freeze as a possible value for the --format option. All those previous years this combination worked (I use it in a shell script) and now it doesn't. So mentioning this moment in the documentation will really help to avoid confusion etc.

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P.S.

Maybe using "cannot" in the above mentioned error message would be more appropriate (sorry, couldn't help mentioning that 😄).