Soft-match dependencies

[r.tirrell@…]

It'd be nice if migration dependency names could be specified in a similar way to migration target names at the command line, e.g., you could:

class Migration(DataMigration):
    depends_on = ((
        ('app', 0004),
        ('users', 0012)
    ))
    # Etc...

This doesn't look too difficult, but I'm not entirely sure where in the Migration or Migrations class the call to guess_migration should be made.

[andrew]

I don't think this is a wise idea (and I'm marking it WONTFIX) because it's too easy to get into a situation where the migration name is ambiguous (there can be more than one migration with the same number if there's been a VCS merge, for example, and South is designed to handle that), and then you'd have the situation where the migration would change from being well-specified to failing to load.