Detect prefixed attributes as duplicated

clippy_lints/src/attrs/duplicated_attributes.rs

@@ -2,6 +2,7 @@ use super::DUPLICATED_ATTRIBUTES;
 use clippy_utils::diagnostics::span_lint_and_then;
 use itertools::Itertools;
 use rustc_ast::{Attribute, MetaItem};
+use rustc_ast_pretty::pprust::path_to_string;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_lint::EarlyContext;
 use rustc_span::{Span, Symbol, sym};
@@ -35,30 +36,38 @@ fn check_duplicated_attr(
     if attr.span.from_expansion() {
         return;
     }
-    let Some(ident) = attr.ident() else { return };
-    let name = ident.name;
-    if name == sym::doc || name == sym::cfg_attr_trace || name == sym::rustc_on_unimplemented || name == sym::reason {
-        // FIXME: Would be nice to handle `cfg_attr` as well. Only problem is to check that cfg
-        // conditions are the same.
-        // `#[rustc_on_unimplemented]` contains duplicated subattributes, that's expected.
-        return;
-    }
-    if let Some(direct_parent) = parent.last()
-        && *direct_parent == sym::cfg_trace
-        && [sym::all, sym::not, sym::any].contains(&name)
-    {
-        // FIXME: We don't correctly check `cfg`s for now, so if it's more complex than just a one
-        // level `cfg`, we leave.
-        return;
+    let attr_path = path_to_string(&attr.path);
+    if let Some(ident) = attr.ident() {
+        let name = ident.name;
+        if name == sym::doc || name == sym::cfg_attr_trace || name == sym::rustc_on_unimplemented || name == sym::reason
+        {
+            // FIXME: Would be nice to handle `cfg_attr` as well. Only problem is to check that cfg
+            // conditions are the same.
+            // `#[rustc_on_unimplemented]` contains duplicated subattributes, that's expected.
+            return;
+        }
+        if let Some(direct_parent) = parent.last()
+            && *direct_parent == sym::cfg_trace
+            && [sym::all, sym::not, sym::any].contains(&name)
+        {
+            // FIXME: We don't correctly check `cfg`s for now, so if it's more complex than just a one
+            // level `cfg`, we leave.
+            return;
+        }
     }
     if let Some(value) = attr.value_str() {
         emit_if_duplicated(
             cx,
             attr,
             attr_paths,
-            format!("{}:{name}={value}", parent.iter().join(":")),
+            format!("{}:{attr_path}={value}", parent.iter().join(":")),
         );
     } else if let Some(sub_attrs) = attr.meta_item_list() {
+        let name = if let Some(ident) = attr.ident() {
+            ident.name
+        } else {
+            Symbol::intern(&attr_path)
+        };
         parent.push(name);
         for sub_attr in sub_attrs {
             if let Some(meta) = sub_attr.meta_item() {
@@ -67,7 +76,7 @@ fn check_duplicated_attr(
         }
         parent.pop();
     } else {
-        emit_if_duplicated(cx, attr, attr_paths, format!("{}:{name}", parent.iter().join(":")));
+        emit_if_duplicated(cx, attr, attr_paths, format!("{}:{attr_path}", parent.iter().join(":")));
     }
 }
 

tests/ui/duplicated_attributes.rs

@@ -1,6 +1,6 @@
 //@aux-build:proc_macro_attr.rs
+#![warn(clippy::duplicated_attributes, clippy::duplicated_attributes)] //~ ERROR: duplicated attribute
 #![feature(rustc_attrs)]
-#![warn(clippy::duplicated_attributes)]
 #![cfg(any(unix, windows))]
 #![allow(dead_code)]
 #![allow(dead_code)] //~ ERROR: duplicated attribute

tests/ui/duplicated_attributes.stderr

@@ -1,3 +1,22 @@
+error: duplicated attribute
+  --> tests/ui/duplicated_attributes.rs:2:40
+   |
+LL | #![warn(clippy::duplicated_attributes, clippy::duplicated_attributes)]
+   |                                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+note: first defined here
+  --> tests/ui/duplicated_attributes.rs:2:9
+   |
+LL | #![warn(clippy::duplicated_attributes, clippy::duplicated_attributes)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+help: remove this attribute
+  --> tests/ui/duplicated_attributes.rs:2:40
+   |
+LL | #![warn(clippy::duplicated_attributes, clippy::duplicated_attributes)]
+   |                                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   = note: `-D clippy::duplicated-attributes` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::duplicated_attributes)]`
+
 error: duplicated attribute
   --> tests/ui/duplicated_attributes.rs:6:10
    |
@@ -14,8 +33,6 @@ help: remove this attribute
    |
 LL | #![allow(dead_code)]
    |          ^^^^^^^^^
-   = note: `-D clippy::duplicated-attributes` implied by `-D warnings`
-   = help: to override `-D warnings` add `#[allow(clippy::duplicated_attributes)]`
 
 error: duplicated attribute
   --> tests/ui/duplicated_attributes.rs:14:9
@@ -34,5 +51,5 @@ help: remove this attribute
 LL | #[allow(dead_code)]
    |         ^^^^^^^^^
 
-error: aborting due to 2 previous errors
+error: aborting due to 3 previous errors
 

tests/ui/indexing_slicing_slice.rs

@@ -12,6 +12,7 @@
     unused
 )]
 #![warn(clippy::indexing_slicing)]
+//~^ duplicated_attributes
 
 extern crate proc_macros;
 use proc_macros::with_span;

tests/ui/indexing_slicing_slice.stderr

@@ -1,5 +1,24 @@
+error: duplicated attribute
+  --> tests/ui/indexing_slicing_slice.rs:14:9
+   |
+LL | #![warn(clippy::indexing_slicing)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+note: first defined here
+  --> tests/ui/indexing_slicing_slice.rs:3:9
+   |
+LL | #![warn(clippy::indexing_slicing)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^
+help: remove this attribute
+  --> tests/ui/indexing_slicing_slice.rs:14:9
+   |
+LL | #![warn(clippy::indexing_slicing)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^
+   = note: `-D clippy::duplicated-attributes` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::duplicated_attributes)]`
+
 error: slicing may panic
-  --> tests/ui/indexing_slicing_slice.rs:115:6
+  --> tests/ui/indexing_slicing_slice.rs:116:6
    |
 LL |     &x[index..];
    |      ^^^^^^^^^^
@@ -9,47 +28,47 @@ LL |     &x[index..];
    = help: to override `-D warnings` add `#[allow(clippy::indexing_slicing)]`
 
 error: slicing may panic
-  --> tests/ui/indexing_slicing_slice.rs:117:6
+  --> tests/ui/indexing_slicing_slice.rs:118:6
    |
 LL |     &x[..index];
    |      ^^^^^^^^^^
    |
    = help: consider using `.get(..n)`or `.get_mut(..n)` instead
 
 error: slicing may panic
-  --> tests/ui/indexing_slicing_slice.rs:119:6
+  --> tests/ui/indexing_slicing_slice.rs:120:6
    |
 LL |     &x[index_from..index_to];
    |      ^^^^^^^^^^^^^^^^^^^^^^^
    |
    = help: consider using `.get(n..m)` or `.get_mut(n..m)` instead
 
 error: slicing may panic
-  --> tests/ui/indexing_slicing_slice.rs:121:6
+  --> tests/ui/indexing_slicing_slice.rs:122:6
    |
 LL |     &x[index_from..][..index_to];
    |      ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = help: consider using `.get(..n)`or `.get_mut(..n)` instead
 
 error: slicing may panic
-  --> tests/ui/indexing_slicing_slice.rs:121:6
+  --> tests/ui/indexing_slicing_slice.rs:122:6
    |
 LL |     &x[index_from..][..index_to];
    |      ^^^^^^^^^^^^^^^
    |
    = help: consider using `.get(n..)` or .get_mut(n..)` instead
 
 error: slicing may panic
-  --> tests/ui/indexing_slicing_slice.rs:124:6
+  --> tests/ui/indexing_slicing_slice.rs:125:6
    |
 LL |     &x[5..][..10];
    |      ^^^^^^^^^^^^
    |
    = help: consider using `.get(..n)`or `.get_mut(..n)` instead
 
 error: range is out of bounds
-  --> tests/ui/indexing_slicing_slice.rs:124:8
+  --> tests/ui/indexing_slicing_slice.rs:125:8
    |
 LL |     &x[5..][..10];
    |        ^
@@ -58,94 +77,94 @@ LL |     &x[5..][..10];
    = help: to override `-D warnings` add `#[allow(clippy::out_of_bounds_indexing)]`
 
 error: slicing may panic
-  --> tests/ui/indexing_slicing_slice.rs:127:6
+  --> tests/ui/indexing_slicing_slice.rs:128:6
    |
 LL |     &x[0..][..3];
    |      ^^^^^^^^^^^
    |
    = help: consider using `.get(..n)`or `.get_mut(..n)` instead
 
 error: slicing may panic
-  --> tests/ui/indexing_slicing_slice.rs:129:6
+  --> tests/ui/indexing_slicing_slice.rs:130:6
    |
 LL |     &x[1..][..5];
    |      ^^^^^^^^^^^
    |
    = help: consider using `.get(..n)`or `.get_mut(..n)` instead
 
 error: range is out of bounds
-  --> tests/ui/indexing_slicing_slice.rs:137:12
+  --> tests/ui/indexing_slicing_slice.rs:138:12
    |
 LL |     &y[0..=4];
    |            ^
 
 error: range is out of bounds
-  --> tests/ui/indexing_slicing_slice.rs:139:11
+  --> tests/ui/indexing_slicing_slice.rs:140:11
    |
 LL |     &y[..=4];
    |           ^
 
 error: slicing may panic
-  --> tests/ui/indexing_slicing_slice.rs:145:6
+  --> tests/ui/indexing_slicing_slice.rs:146:6
    |
 LL |     &v[10..100];
    |      ^^^^^^^^^^
    |
    = help: consider using `.get(n..m)` or `.get_mut(n..m)` instead
 
 error: slicing may panic
-  --> tests/ui/indexing_slicing_slice.rs:147:6
+  --> tests/ui/indexing_slicing_slice.rs:148:6
    |
 LL |     &x[10..][..100];
    |      ^^^^^^^^^^^^^^
    |
    = help: consider using `.get(..n)`or `.get_mut(..n)` instead
 
 error: range is out of bounds
-  --> tests/ui/indexing_slicing_slice.rs:147:8
+  --> tests/ui/indexing_slicing_slice.rs:148:8
    |
 LL |     &x[10..][..100];
    |        ^^
 
 error: slicing may panic
-  --> tests/ui/indexing_slicing_slice.rs:150:6
+  --> tests/ui/indexing_slicing_slice.rs:151:6
    |
 LL |     &v[10..];
    |      ^^^^^^^
    |
    = help: consider using `.get(n..)` or .get_mut(n..)` instead
 
 error: slicing may panic
-  --> tests/ui/indexing_slicing_slice.rs:152:6
+  --> tests/ui/indexing_slicing_slice.rs:153:6
    |
 LL |     &v[..100];
    |      ^^^^^^^^
    |
    = help: consider using `.get(..n)`or `.get_mut(..n)` instead
 
 error: indexing may panic
-  --> tests/ui/indexing_slicing_slice.rs:170:5
+  --> tests/ui/indexing_slicing_slice.rs:171:5
    |
 LL |     map_with_get[true];
    |     ^^^^^^^^^^^^^^^^^^
    |
    = help: consider using `.get(n)` or `.get_mut(n)` instead
 
 error: indexing may panic
-  --> tests/ui/indexing_slicing_slice.rs:174:5
+  --> tests/ui/indexing_slicing_slice.rs:175:5
    |
 LL |     s[0];
    |     ^^^^
    |
    = help: consider using `.get(n)` or `.get_mut(n)` instead
 
 error: indexing may panic
-  --> tests/ui/indexing_slicing_slice.rs:178:5
+  --> tests/ui/indexing_slicing_slice.rs:179:5
    |
 LL |     y[0];
    |     ^^^^
    |
    = help: consider using `.get(n)` or `.get_mut(n)` instead
 
-error: aborting due to 19 previous errors
+error: aborting due to 20 previous errors
 

tests/ui/needless_collect_indirect.rs

@@ -1,5 +1,6 @@
 #![allow(clippy::uninlined_format_args, clippy::useless_vec)]
 #![allow(clippy::needless_if, clippy::uninlined_format_args)]
+//~^ duplicated_attributes
 #![warn(clippy::needless_collect)]
 //@no-rustfix
 use std::collections::{BinaryHeap, HashMap, HashSet, LinkedList, VecDeque};