Flag: no defaults

[steveklabnik]

This issue is part of #125

--no-defaults: don't run default passes

Using this flag looks like this:

$ rustdoc src/lib.rs --no-defaults

By default, rustdoc will run several passes over your code. This
removes those defaults, allowing you to use --passes to specify
exactly which passes you want.

For more details on passes, see the chapter on them.

See also --passes.

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Should we keep this flag or not?

[steveklabnik]

We don't currently have the "passes" architecture, so I'm not sure this flag makes sense.

Existing usage, as far as I know, is mostly to use it in combination with --passes in order to document private things, which we can instead support more directly.

[steveklabnik]

We talked about this at the tools team meeting today and the intention is to remove this flag. Passes don't make much sense in new rustdoc.

[steveklabnik]

rust-lang/rust#44136 is the issue tracking the deprecation; it may or may not be removed, but it means we don't need to support it.