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Feature Request

Since Poetry 1.0 we can specify the source of package in the pyproject.toml, in order to use another index than PyPI. This is very convenient, but there is no way to specify this when using the poetry add command.

This is especially inconvenient when you're trying to update an existing private dependency with poetry add, as it will erase its source.

My suggestion would be to add a --source option to poetry add, taking the name of a source defined in the pyproject.toml. I don't think adding a package from a source not defined previously should be accepted.