Support #[expect] attributes for rustdoc lints (RFC 2383)

Author: xFrednet

src/librustdoc/core.rs

@@ -232,6 +232,8 @@ crate fn create_config(
         rustc_lint::builtin::RENAMED_AND_REMOVED_LINTS.name.to_string(),
         rustc_lint::builtin::UNKNOWN_LINTS.name.to_string(),
         rustc_lint::builtin::UNEXPECTED_CFGS.name.to_string(),
+        // this lint is needed to support `#[expect]` attributes
+        rustc_lint::builtin::UNFULFILLED_LINT_EXPECTATIONS.name.to_string(),
     ];
     lints_to_show.extend(crate::lint::RUSTDOC_LINTS.iter().map(|lint| lint.name.to_string()));
 
@@ -463,6 +465,8 @@ crate fn run_global_ctxt(
         }
     }
 
+    tcx.sess.time("check_lint_expectations", || tcx.check_expectations(Some(sym::rustdoc)));
+
     if tcx.sess.diagnostic().has_errors_or_lint_errors().is_some() {
         rustc_errors::FatalError.raise();
     }

src/test/rustdoc-ui/expect-tool-lint-rfc-2383.rs

@@ -0,0 +1,157 @@
+// check-pass
+#![feature(lint_reasons)]
+
+//! This file tests the `#[expect]` attribute implementation for tool lints. The same
+//! file is used to test clippy and rustdoc. Any changes to this file should be synced
+//! to the other test files as well.
+//!
+//! Expectations:
+//! * rustc: only rustc lint expectations are emitted
+//! * clippy: rustc and Clippy's expectations are emitted
+//! * rustdoc: only rustdoc lint expectations are emitted
+//!
+//! This test can't cover every lint from Clippy, rustdoc and potentially other
+//! tools that will be developed. This therefore only tests a small subset of lints
+
+#![expect(rustdoc::missing_crate_level_docs)]
+//~^ WARNING this lint expectation is unfulfilled [unfulfilled_lint_expectations]
+//~| NOTE `#[warn(unfulfilled_lint_expectations)]` on by default
+
+mod rustc_ok {
+    //! See <https://doc.rust-lang.org/rustc/lints/index.html>
+
+    #[expect(dead_code)]
+    pub fn rustc_lints() {
+        let x = 42.0;
+
+        #[expect(illegal_floating_point_literal_pattern)]
+        match x {
+            5.0 => {}
+            6.0 => {}
+            _ => {}
+        }
+    }
+}
+
+mod rustc_warn {
+    //! See <https://doc.rust-lang.org/rustc/lints/index.html>
+
+    #[expect(dead_code)]
+    pub fn rustc_lints() {
+        let x = 42;
+
+        #[expect(illegal_floating_point_literal_pattern)]
+        match x {
+            5 => {}
+            6 => {}
+            _ => {}
+        }
+    }
+}
+
+pub mod rustdoc_ok {
+    //! See <https://doc.rust-lang.org/rustdoc/lints.html>
+
+    #[expect(rustdoc::broken_intra_doc_links)]
+    /// I want to link to [`Nonexistent`] but it doesn't exist!
+    pub fn foo() {}
+
+    #[expect(rustdoc::invalid_html_tags)]
+    /// <h1>
+    pub fn bar() {}
+
+    #[expect(rustdoc::bare_urls)]
+    /// http://example.org
+    pub fn baz() {}
+}
+
+pub mod rustdoc_warn {
+    //! See <https://doc.rust-lang.org/rustdoc/lints.html>
+
+    #[expect(rustdoc::broken_intra_doc_links)]
+    //~^ WARNING this lint expectation is unfulfilled [unfulfilled_lint_expectations]
+    /// I want to link to [`bar`] but it doesn't exist!
+    pub fn foo() {}
+
+    #[expect(rustdoc::invalid_html_tags)]
+    //~^ WARNING this lint expectation is unfulfilled [unfulfilled_lint_expectations]
+    /// <h1></h1>
+    pub fn bar() {}
+
+    #[expect(rustdoc::bare_urls)]
+    //~^ WARNING this lint expectation is unfulfilled [unfulfilled_lint_expectations]
+    /// <http://example.org>
+    pub fn baz() {}
+}
+
+mod clippy_ok {
+    //! See <https://rust-lang.github.io/rust-clippy/master/index.html>
+
+    #[expect(clippy::almost_swapped)]
+    fn foo() {
+        let mut a = 0;
+        let mut b = 9;
+        a = b;
+        b = a;
+    }
+
+    #[expect(clippy::bytes_nth)]
+    fn bar() {
+        let _ = "Hello".bytes().nth(3);
+    }
+
+    #[expect(clippy::if_same_then_else)]
+    fn baz() {
+        let _ = if true {
+            42
+        } else {
+            42
+        };
+    }
+
+    #[expect(clippy::logic_bug)]
+    fn burger() {
+        let a = false;
+        let b = true;
+
+        if a && b || a {}
+    }
+}
+
+mod clippy_warn {
+    //! See <https://rust-lang.github.io/rust-clippy/master/index.html>
+
+    #[expect(clippy::almost_swapped)]
+    fn foo() {
+        let mut a = 0;
+        let mut b = 9;
+        a = b;
+    }
+
+    #[expect(clippy::bytes_nth)]
+    fn bar() {
+        let _ = "Hello".as_bytes().get(3);
+    }
+
+    #[expect(clippy::if_same_then_else)]
+    fn baz() {
+        let _ = if true {
+            33
+        } else {
+            42
+        };
+    }
+
+    #[expect(clippy::logic_bug)]
+    fn burger() {
+        let a = false;
+        let b = true;
+        let c = false;
+
+        if a && b || c {}
+    }
+}
+
+fn main() {
+    rustc_warn::rustc_lints();
+}

src/test/rustdoc-ui/expect-tool-lint-rfc-2383.stderr

@@ -0,0 +1,28 @@
+warning: this lint expectation is unfulfilled
+  --> $DIR/expect-tool-lint-rfc-2383.rs:16:11
+   |
+LL | #![expect(rustdoc::missing_crate_level_docs)]
+   |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `#[warn(unfulfilled_lint_expectations)]` on by default
+
+warning: this lint expectation is unfulfilled
+  --> $DIR/expect-tool-lint-rfc-2383.rs:71:14
+   |
+LL |     #[expect(rustdoc::broken_intra_doc_links)]
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+warning: this lint expectation is unfulfilled
+  --> $DIR/expect-tool-lint-rfc-2383.rs:76:14
+   |
+LL |     #[expect(rustdoc::invalid_html_tags)]
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+warning: this lint expectation is unfulfilled
+  --> $DIR/expect-tool-lint-rfc-2383.rs:81:14
+   |
+LL |     #[expect(rustdoc::bare_urls)]
+   |              ^^^^^^^^^^^^^^^^^^
+
+warning: 4 warnings emitted
+