rustdoc: Inlining a foreign public struct with private fields shows the fields as private in the current crate

[jyn514]

// inner crate
pub struct S {
  pub x: i32,
  y: i32,
}

// outer crate
pub use inner::S;

Originally posted by @jyn514 in #91408 (comment)

[BGR360]

Can anybody more familiar with rustdoc put an E-{easy,medium,hard} and/or an E-mentor on here?

[jyn514]

@BGR360 I honestly don't understand this code very well either, but the way I'd suggest getting started is looking at

rust/src/librustdoc/clean/inline.rs

Lines 129 to 131 in e91ad5f

	if let Some(import_def_id) = import_def_id {
	// The visibility needs to reflect the one from the reexport and not from the "source" DefId.
	item.visibility = cx.tcx.visibility(import_def_id).clean(cx);

- I think part of the issue is that rustdoc treats struct fields as their own item: https://doc.rust-lang.org/nightly/nightly-rustc/rustdoc/clean/types/enum.ItemKind.html#variant.StructFieldItem, so it gets confused when structs are re-exported and thinks the visibility of the re-export applies to the field too.

[jyn514]

@fmease you need to also pass --document-private-items