"missing installed component" error should be translated through renames

[joshtriplett]

As documented, component names passed to rustup component add are translated through the renames table, and component names in rustup component list are translated backwards through renames. However, when rustup skips a nightly version because it doesn't have an installed component, the error message gives the "preview" component name, and doesn't translate backwards through renames:

info: syncing channel updates for 'nightly-x86_64-unknown-linux-gnu'
info: latest update on 2020-07-25, rust version 1.47.0-nightly (5ef299eb9 2020-07-24)
info: skipping nightly which is missing installed component 'rustfmt-preview'
info: syncing channel updates for 'nightly-2020-07-24-x86_64-unknown-linux-gnu'
info: latest update on 2020-07-24, rust version 1.47.0-nightly (0820e54a8 2020-07-23)
info: skipping nightly which is missing installed component 'rustfmt-preview'

rustup --version: rustup 1.22.1 (b01adbbc3 2020-07-08)
rustup show:

Default host: x86_64-unknown-linux-gnu
rustup home:  /home/josh/.rustup

installed toolchains
--------------------

stable-x86_64-unknown-linux-gnu (default)
nightly-x86_64-unknown-linux-gnu
system

installed targets for active toolchain
--------------------------------------

wasm32-wasi
x86_64-unknown-linux-gnu

active toolchain
----------------

stable-x86_64-unknown-linux-gnu (default)
rustc 1.45.0 (5c1f21c3b 2020-07-13)

[kinnison]

Well spotted. This should definitely be fixed otherwise users may get confused.

[kinnison]

This ought to be fairly straightforward to correct. I'd be happy to discuss it either here or on Discord with anyone interested in attempting a fix.

[rbtcollins]

We should probably fix the stringification stuff for these types so that it is fixed systematically.

[kinnison]

We should probably fix the stringification stuff for these types so that it is fixed systematically.

IIRC the component doesn't have back-references to its manifest which is needed for renaming.

[rbtcollins]

This bug describes how the message that is output should be translated to deal with the metadata in the publication process that deal with publishing it on the web.

Your question/error is something to do with the installation process, and entirely unrelated to this bug, other than that the same message which is being discussed is output in both cases.

Please follow the request and open a new ticket, it was made in good faith.