Add rust to let_underscore_lock example

[saschanaz]

Currently https://doc.rust-lang.org/beta/rustc/lints/listing/deny-by-default.html#let-underscore-lock has no colored grammar and raw {{produces}} command is exposed.

[rust-highfive]

r? @eholk

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[saschanaz]

(Will add other linters later)

[ehuss]

There is a bug in the tooling that should have prevented this from happening. Would you mind adding the following patch when fixing the other lints?

diff --git a/src/tools/lint-docs/src/lib.rs b/src/tools/lint-docs/src/lib.rs
index 857feb77325..3842a649c6f 100644
--- a/src/tools/lint-docs/src/lib.rs
+++ b/src/tools/lint-docs/src/lib.rs
@@ -37,10 +37,8 @@ fn doc_contains(&self, text: &str) -> bool {
     }

     fn is_ignored(&self) -> bool {
-        self.doc
-            .iter()
-            .filter(|line| line.starts_with("```rust"))
-            .all(|line| line.contains(",ignore"))
+        let blocks: Vec<_> = self.doc.iter().filter(|line| line.starts_with("```rust")).collect();
+        !blocks.is_empty() && blocks.iter().all(|line| line.contains(",ignore"))
     }

     /// Checks the doc style of the lint.

[saschanaz]

Had to copypaste from the tests since the example didn't emit the warning. @compiler-errors

[ehuss]

Thanks!

@bors r+ rollup

[bors]

📌 Commit 30b5223 has been approved by ehuss

It is now in the queue for this repository.

[bors]

☔ The latest upstream changes (presumably #104428) made this pull request unmergeable. Please resolve the merge conflicts.

[saschanaz]

Wait, why are the jobs canceled when there is no failure? 🤔

[ehuss]

There is an internal error, it has been affecting other PRs today.

GitHub Actions has encountered an internal error when running your job.

@bors r+ rollup

[bors]

📌 Commit 0a528b1 has been approved by ehuss

It is now in the queue for this repository.