rustdoc --json output format, crate.paths does not contain all items

[makspll]

#76578

Code

Running
$ rustup run nightly-2022-11-20 cargo rustdoc -p bevy_asset@0.9.0 -- -Zunstable-options --output-format json
generates a json file whose paths mapping does not contain many of the internal structures such us:
AssetPathId, SourcePathId, HandleId, LabelId etc.

Not sure if this is intended, but without this mapping there is no way as far as I am aware to retrieve the original import paths to these things.

Version it worked on

nightly-2022-08-01

Version with regression

nightly-2022-11-20

[GuillaumeGomez]

Do you have a minimized example of the regression by any chance?

[Enselic]

Not sure if this is intended, but without this mapping there is no way as far as I am aware to retrieve the original import paths to these things.

Due to re-exports, a single item can have many paths. And the path to the "real" item may be inaccessible behind a private mod. To learn about all the paths to an item, you must traverse the items from the root. You must also take into account renames (pub use foo as bar), as well as recursive re-exports.

If you want to look at (one way) of doing that you can look at https://github.com/Enselic/cargo-public-api/blob/main/public-api/src/item_processor.rs

The paths structure in the rustdoc JSON is something that will be removed long term. Because it is not really useful. It contains internal paths, and only one path. Long term, all items shall be part of the index. And the items you mention are already part of the index I think? You can check with cargo public-api:

$ cargo install cargo-public-api
$ rustup install nightly
$ git clone https://github.com/bevyengine/bevy.git ; cd bevy
$ cargo public-api -p bevy_asset  | grep AssetPathId
[...]
pub struct bevy_asset::AssetPathId(_, _)
[...]

cargo public-api parses the rustdoc JSON, so if cargo public-api finds an item, it is part of rustdoc JSON.

[makspll]

Hmm, thanks everyone, it seems that there is a way then to retrieve import paths which I am happy with. Closing and will re-open if there are any issues with this.

[GuillaumeGomez]

Maybe we could provide some methods in the rustdonc-json crate to make it easier for our users to get this information?

[makspll]

That would be very useful indeed, for context I use these to import structures for which I am generating wrappers

[GuillaumeGomez]

Then please open another issue (linking to this one) with a short example of your problem so we can provide you a function to make it easier. ;)

[Enselic]

@GuillaumeGomez I think you meant to say "the rustdoc-types crate" rather than "the rustdoc-json crate", right?

@makspll The "source" for rustdoc-types is here: https://github.com/rust-lang/rust/tree/master/src/rustdoc-json-types.