Recognize private_intra_doc_links as a lint

[jyn514]

Previously, trying to allow this would give another error!

warning: unknown lint: `private_intra_doc_links`
 --> private.rs:1:10
  |
1 | #![allow(private_intra_doc_links)]
  |          ^^^^^^^^^^^^^^^^^^^^^^^ help: did you mean: `broken_intra_doc_links`
  |
  = note: `#[warn(unknown_lints)]` on by default

warning: public documentation for `DocMe` links to private item `DontDocMe`
 --> private.rs:2:11
  |
2 | /// docs [DontDocMe]
  |           ^^^^^^^^^ this item is private
  |
  = note: `#[warn(private_intra_doc_links)]` on by default
  = note: this link will resolve properly if you pass `--document-private-items`

Fixes the issue found in #77249 (comment).

r? @Manishearth

Does anyone know why this additional step is necessary? It seems weird this has to be declared in 3 different places.

[Manishearth]

Because it's a rustdoc-exclusive lint and is otherwise only declared in rustdoc code

@bors r+

[bors]

📌 Commit f2078877f230567d5ddbcabdf5b6016f5979e204 has been approved by Manishearth

[jyn514]

@bors r-

This causes the tests to fail and I don't understand why:

---- [ui] rustdoc-ui/intra-links-private.rs#private stdout ----
diff of stderr:

-	warning: public documentation for `DocMe` links to private item `DontDocMe`
-	  --> $DIR/intra-links-private.rs:5:11
-	   |
-	LL | /// docs [DontDocMe]
-	   |           ^^^^^^^^^ this item is private
-	   |
-	   = note: `#[warn(private_intra_doc_links)]` on by default
-	   = note: this link resolves only because you passed `--document-private-items`, but will break without
-	
-	warning: 1 warning emitted
-	
-	

[oli-obk]

Rustdoc has its own lint list.

In

rust/src/librustdoc/core.rs

Line 251 in 8ae3b50

lint::builtin::HardwiredLints::get_lints()

the hardwired lints are extracted and filtered. The actual list is

rust/src/librustdoc/core.rs

Line 337 in 8ae3b50

let lints_to_show = vec![

Though I don't get the double check in

rust/src/librustdoc/core.rs

Line 350 in 8ae3b50

if lint.name == intra_link_resolution_failure_name

(cc @GuillaumeGomez )

Anyway, I think adding the lint to lints_to_show should make it work again

[GuillaumeGomez]

@oli-obk The check you linked is to prevent some lints to be allowed by default iirc.

[jyn514]

I think the right fix here is to never silence lints from the rustdoc lint group, then there wouldn't be so many places to add new lints.

How do I get the rustdoc lint group? I found LintStore::lint_groups, but I don't know how to get a LintStore.

[jyn514]

Queries::register_plugins looks right, but rustdoc only has access to Queries after it already creates the config, and that can't be fixed because create_compiler_and_run takes a config and comes before compiler.enter.

Is there really no simpler way to do this?

[jyn514]

I changed this to hard-code the lints for now, but I'd really like to fix this at some point.

[oli-obk]

@bors r+

yea, let's get this landed for now.

[bors]

📌 Commit 47b21b8 has been approved by oli-obk