1 files changed, 34 insertions, 3 deletions
diff --git a/src/tools/clippy/clippy_lints/src/functions/mod.rs b/src/tools/clippy/clippy_lints/src/functions/mod.rs
index 9dbce3f88..d2852b4ac 100644
--- a/src/tools/clippy/clippy_lints/src/functions/mod.rs
+++ b/src/tools/clippy/clippy_lints/src/functions/mod.rs
@@ -1,3 +1,4 @@
+mod impl_trait_in_params;
 mod misnamed_getters;
 mod must_use;
 mod not_unsafe_ptr_arg_deref;
@@ -9,6 +10,7 @@ use rustc_hir as hir;
 use rustc_hir::intravisit;
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_tool_lint, impl_lint_pass};
+use rustc_span::def_id::LocalDefId;
 use rustc_span::Span;
 
 declare_clippy_lint! {
@@ -326,6 +328,32 @@ declare_clippy_lint! {
     "getter method returning the wrong field"
 }
 
+declare_clippy_lint! {
+    /// ### What it does
+    /// Lints when `impl Trait` is being used in a function's paremeters.
+    /// ### Why is this bad?
+    /// Turbofish syntax (`::<>`) cannot be used when `impl Trait` is being used, making `impl Trait` less powerful. Readability may also be a factor.
+    ///
+    /// ### Example
+    /// ```rust
+    /// trait MyTrait {}
+    /// fn foo(a: impl MyTrait) {
+    /// 	// [...]
+    /// }
+    /// ```
+    /// Use instead:
+    /// ```rust
+    /// trait MyTrait {}
+    /// fn foo<T: MyTrait>(a: T) {
+    /// 	// [...]
+    /// }
+    /// ```
+    #[clippy::version = "1.68.0"]
+    pub IMPL_TRAIT_IN_PARAMS,
+    restriction,
+    "`impl Trait` is used in the function's parameters"
+}
+
 #[derive(Copy, Clone)]
 pub struct Functions {
     too_many_arguments_threshold: u64,
@@ -353,6 +381,7 @@ impl_lint_pass!(Functions => [
     RESULT_UNIT_ERR,
     RESULT_LARGE_ERR,
     MISNAMED_GETTERS,
+    IMPL_TRAIT_IN_PARAMS,
 ]);
 
 impl<'tcx> LateLintPass<'tcx> for Functions {
@@ -363,12 +392,14 @@ impl<'tcx> LateLintPass<'tcx> for Functions {
         decl: &'tcx hir::FnDecl<'_>,
         body: &'tcx hir::Body<'_>,
         span: Span,
-        hir_id: hir::HirId,
+        def_id: LocalDefId,
     ) {
+        let hir_id = cx.tcx.hir().local_def_id_to_hir_id(def_id);
         too_many_arguments::check_fn(cx, kind, decl, span, hir_id, self.too_many_arguments_threshold);
         too_many_lines::check_fn(cx, kind, span, body, self.too_many_lines_threshold);
-        not_unsafe_ptr_arg_deref::check_fn(cx, kind, decl, body, hir_id);
-        misnamed_getters::check_fn(cx, kind, decl, body, span, hir_id);
+        not_unsafe_ptr_arg_deref::check_fn(cx, kind, decl, body, def_id);
+        misnamed_getters::check_fn(cx, kind, decl, body, span);
+        impl_trait_in_params::check_fn(cx, &kind, body, hir_id);
     }
 
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'_>) {