Auto merge of #12755 - 9999years:useless-attribute, r=xFrednet,GuillaumeGomez

Allow more attributes in `clippy::useless_attribute`

Fixes #12753
Fixes #4467
Fixes #11595
Fixes #10878

changelog: [`useless_attribute`]: Attributes allowed on `use` items now include `ambiguous_glob_exports`, `hidden_glob_reexports`, `dead_code`, `unused_braces`, and `clippy::disallowed_types`.

Author: bors

clippy_lints/src/attrs/mod.rs

@@ -61,11 +61,21 @@ declare_clippy_lint! {
     ///
     /// This lint permits lint attributes for lints emitted on the items themself.
     /// For `use` items these lints are:
+    /// * ambiguous_glob_reexports
+    /// * dead_code
     /// * deprecated
+    /// * hidden_glob_reexports
     /// * unreachable_pub
-    /// * unused_imports
+    /// * unused
+    /// * unused_braces
+    /// * unused_import_braces
+    /// * clippy::disallowed_types
     /// * clippy::enum_glob_use
     /// * clippy::macro_use_imports
+    /// * clippy::module_name_repetitions
+    /// * clippy::redundant_pub_crate
+    /// * clippy::single_component_path_imports
+    /// * clippy::unsafe_removed_from_name
     /// * clippy::wildcard_imports
     ///
     /// For `extern crate` items these lints are:

clippy_lints/src/attrs/useless_attribute.rs

@@ -2,6 +2,7 @@ use super::utils::{extract_clippy_lint, is_lint_level, is_word};
 use super::{Attribute, USELESS_ATTRIBUTE};
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::source::{first_line_of_span, snippet_opt};
+use rustc_ast::NestedMetaItem;
 use rustc_errors::Applicability;
 use rustc_hir::{Item, ItemKind};
 use rustc_lint::{LateContext, LintContext};
@@ -20,26 +21,40 @@ pub(super) fn check(cx: &LateContext<'_>, item: &Item<'_>, attrs: &[Attribute])
                 for lint in lint_list {
                     match item.kind {
                         ItemKind::Use(..) => {
-                            if is_word(lint, sym::unused_imports)
-                                || is_word(lint, sym::deprecated)
-                                || is_word(lint, sym!(unreachable_pub))
-                                || is_word(lint, sym!(unused))
-                                || is_word(lint, sym!(unused_import_braces))
-                                || extract_clippy_lint(lint).map_or(false, |s| {
-                                    matches!(
-                                        s.as_str(),
-                                        "wildcard_imports"
-                                            | "enum_glob_use"
-                                            | "redundant_pub_crate"
-                                            | "macro_use_imports"
-                                            | "unsafe_removed_from_name"
-                                            | "module_name_repetitions"
-                                            | "single_component_path_imports"
-                                    )
-                                })
+                            if let NestedMetaItem::MetaItem(meta_item) = lint
+                                && meta_item.is_word()
+                                && let Some(ident) = meta_item.ident()
+                                && matches!(
+                                    ident.name.as_str(),
+                                    "ambiguous_glob_reexports"
+                                        | "dead_code"
+                                        | "deprecated"
+                                        | "hidden_glob_reexports"
+                                        | "unreachable_pub"
+                                        | "unused"
+                                        | "unused_braces"
+                                        | "unused_import_braces"
+                                        | "unused_imports"
+                                )
                             {
                                 return;
                             }
+
+                            if extract_clippy_lint(lint).is_some_and(|symbol| {
+                                matches!(
+                                    symbol.as_str(),
+                                    "wildcard_imports"
+                                        | "enum_glob_use"
+                                        | "redundant_pub_crate"
+                                        | "macro_use_imports"
+                                        | "unsafe_removed_from_name"
+                                        | "module_name_repetitions"
+                                        | "single_component_path_imports"
+                                        | "disallowed_types"
+                                )
+                            }) {
+                                return;
+                            }
                         },
                         ItemKind::ExternCrate(..) => {
                             if is_word(lint, sym::unused_imports) && skip_unused_imports {

tests/ui-toml/toml_disallowed_types/conf_disallowed_types.rs

@@ -40,3 +40,9 @@ fn main() {
     let _ = HashMap;
     let _: usize = 64_usize;
 }
+
+mod useless_attribute {
+    // Regression test for https://github.com/rust-lang/rust-clippy/issues/12753
+    #[allow(clippy::disallowed_types)]
+    use std::collections::HashMap;
+}

tests/ui/useless_attribute.fixed

@@ -86,8 +86,51 @@ mod module {
 
 #[rustfmt::skip]
 #[allow(unused_import_braces)]
+#[allow(unused_braces)]
 use module::{Struct};
 
 fn main() {
     test_indented_attr();
 }
+
+// Regression test for https://github.com/rust-lang/rust-clippy/issues/4467
+#[allow(dead_code)]
+use std::collections as puppy_doggy;
+
+// Regression test for https://github.com/rust-lang/rust-clippy/issues/11595
+pub mod hidden_glob_reexports {
+    #![allow(unreachable_pub)]
+
+    mod my_prelude {
+        pub struct MyCoolTypeInternal;
+        pub use MyCoolTypeInternal as MyCoolType;
+    }
+
+    mod my_uncool_type {
+        pub(crate) struct MyUncoolType;
+    }
+
+    // This exports `MyCoolType`.
+    pub use my_prelude::*;
+
+    // This hides `my_prelude::MyCoolType`.
+    #[allow(hidden_glob_reexports)]
+    use my_uncool_type::MyUncoolType as MyCoolType;
+}
+
+// Regression test for https://github.com/rust-lang/rust-clippy/issues/10878
+pub mod ambiguous_glob_exports {
+    #![allow(unreachable_pub)]
+
+    mod my_prelude {
+        pub struct MyType;
+    }
+
+    mod my_type {
+        pub struct MyType;
+    }
+
+    #[allow(ambiguous_glob_reexports)]
+    pub use my_prelude::*;
+    pub use my_type::*;
+}

tests/ui/useless_attribute.rs

@@ -86,8 +86,51 @@ mod module {
 
 #[rustfmt::skip]
 #[allow(unused_import_braces)]
+#[allow(unused_braces)]
 use module::{Struct};
 
 fn main() {
     test_indented_attr();
 }
+
+// Regression test for https://github.com/rust-lang/rust-clippy/issues/4467
+#[allow(dead_code)]
+use std::collections as puppy_doggy;
+
+// Regression test for https://github.com/rust-lang/rust-clippy/issues/11595
+pub mod hidden_glob_reexports {
+    #![allow(unreachable_pub)]
+
+    mod my_prelude {
+        pub struct MyCoolTypeInternal;
+        pub use MyCoolTypeInternal as MyCoolType;
+    }
+
+    mod my_uncool_type {
+        pub(crate) struct MyUncoolType;
+    }
+
+    // This exports `MyCoolType`.
+    pub use my_prelude::*;
+
+    // This hides `my_prelude::MyCoolType`.
+    #[allow(hidden_glob_reexports)]
+    use my_uncool_type::MyUncoolType as MyCoolType;
+}
+
+// Regression test for https://github.com/rust-lang/rust-clippy/issues/10878
+pub mod ambiguous_glob_exports {
+    #![allow(unreachable_pub)]
+
+    mod my_prelude {
+        pub struct MyType;
+    }
+
+    mod my_type {
+        pub struct MyType;
+    }
+
+    #[allow(ambiguous_glob_reexports)]
+    pub use my_prelude::*;
+    pub use my_type::*;
+}