Lint disallowed function names

clippy_lints/src/disallowed_names.rs

@@ -2,10 +2,11 @@ use clippy_config::Conf;
 use clippy_utils::diagnostics::span_lint;
 use clippy_utils::is_in_test;
 use rustc_data_structures::fx::FxHashSet;
-use rustc_hir::{Pat, PatKind};
+use rustc_hir::intravisit::FnKind;
+use rustc_hir::{HirId, Pat, PatKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::impl_lint_pass;
-use rustc_span::Symbol;
+use rustc_span::{Ident, Symbol};
 
 declare_clippy_lint! {
     /// ### What it does
@@ -36,16 +37,9 @@ impl DisallowedNames {
             disallow: conf.disallowed_names.iter().map(|x| Symbol::intern(x)).collect(),
         }
     }
-}
-
-impl_lint_pass!(DisallowedNames => [DISALLOWED_NAMES]);
 
-impl<'tcx> LateLintPass<'tcx> for DisallowedNames {
-    fn check_pat(&mut self, cx: &LateContext<'tcx>, pat: &'tcx Pat<'_>) {
-        if let PatKind::Binding(.., ident, _) = pat.kind
-            && self.disallow.contains(&ident.name)
-            && !is_in_test(cx.tcx, pat.hir_id)
-        {
+    fn check(&mut self, cx: &LateContext<'_>, ident: Ident, hir_id: HirId) {
+        if self.disallow.contains(&ident.name) && !is_in_test(cx.tcx, hir_id) {
             span_lint(
                 cx,
                 DISALLOWED_NAMES,
@@ -55,3 +49,33 @@ impl<'tcx> LateLintPass<'tcx> for DisallowedNames {
         }
     }
 }
+
+impl_lint_pass!(DisallowedNames => [DISALLOWED_NAMES]);
+
+impl<'tcx> LateLintPass<'tcx> for DisallowedNames {
+    fn check_pat(&mut self, cx: &LateContext<'tcx>, pat: &'tcx Pat<'_>) {
+        if let PatKind::Binding(.., ident, _) = pat.kind {
+            self.check(cx, ident, pat.hir_id);
+        }
+    }
+
+    fn check_fn(
+        &mut self,
+        cx: &LateContext<'tcx>,
+        kind: FnKind<'tcx>,
+        _: &'tcx rustc_hir::FnDecl<'tcx>,
+        _: &'tcx rustc_hir::Body<'tcx>,
+        _: rustc_span::Span,
+        _: rustc_span::def_id::LocalDefId,
+    ) {
+        match kind {
+            FnKind::ItemFn(ident, ..) => {
+                self.check(cx, ident, cx.last_node_with_lint_attrs);
+            },
+            FnKind::Method(ident, _) => {
+                self.check(cx, ident, cx.last_node_with_lint_attrs);
+            },
+            _ => {},
+        }
+    }
+}

tests/ui/disallowed_names.rs

@@ -83,3 +83,25 @@ mod tests {
 fn test_with_disallowed_name() {
     let foo = 0;
 }
+
+mod functions_test {
+    fn foo() {}
+    //~^ disallowed_names
+
+    pub fn quux(_some_meaningful_arg: i32) {}
+    //~^ disallowed_names
+
+    pub async fn baz(_more_meaningful_arg: bool) {}
+    //~^ disallowed_names
+
+    fn do_not_lint_foo() {}
+
+    struct SomeMeaningfulStruct {}
+    impl SomeMeaningfulStruct {
+        fn foo(&self) {}
+        //~^ disallowed_names
+
+        const fn baz(&self) {}
+        //~^ disallowed_names
+    }
+}

tests/ui/disallowed_names.stderr

@@ -85,5 +85,35 @@ error: use of a disallowed/placeholder name `quux`
 LL |     if let Some(ref mut quux) = Some(42) {}
    |                         ^^^^
 
-error: aborting due to 14 previous errors
+error: use of a disallowed/placeholder name `foo`
+  --> tests/ui/disallowed_names.rs:88:8
+   |
+LL |     fn foo() {}
+   |        ^^^
+
+error: use of a disallowed/placeholder name `quux`
+  --> tests/ui/disallowed_names.rs:91:12
+   |
+LL |     pub fn quux(_some_meaningful_arg: i32) {}
+   |            ^^^^
+
+error: use of a disallowed/placeholder name `baz`
+  --> tests/ui/disallowed_names.rs:94:18
+   |
+LL |     pub async fn baz(_more_meaningful_arg: bool) {}
+   |                  ^^^
+
+error: use of a disallowed/placeholder name `foo`
+  --> tests/ui/disallowed_names.rs:101:12
+   |
+LL |         fn foo(&self) {}
+   |            ^^^
+
+error: use of a disallowed/placeholder name `baz`
+  --> tests/ui/disallowed_names.rs:104:18
+   |
+LL |         const fn baz(&self) {}
+   |                  ^^^
+
+error: aborting due to 19 previous errors