Rollup merge of rust-lang#120000 - smoelius:fix-clippy, r=fee1-dead

Ensure `callee_id`s are body owners

This PR makes the `callee_id` argument of Clippy's `implements_trait_with_env` optional, and when it is passed, ensures it is a body owner.

rust-lang#118661 added the `callee_id` parameter to alleviate an ICE. Specifically, the `callee_id` is used to determine an "effect arg" in certain situations.

Frankly, I [do not completely understand](rust-lang#118661 (comment)) what an "effect arg" is. But the code that determines it seems to require that `callee_id` is a body owner:
- https://github.com/rust-lang/rust/blob/1ead4761e9e2f056385768614c23ffa7acb6a19e/src/tools/clippy/clippy_utils/src/ty.rs#L286-L288
- https://github.com/rust-lang/rust/blob/1ead4761e9e2f056385768614c23ffa7acb6a19e/compiler/rustc_middle/src/ty/util.rs#L834
- https://github.com/rust-lang/rust/blob/1ead4761e9e2f056385768614c23ffa7acb6a19e/compiler/rustc_middle/src/hir/map/mod.rs#L372

In the current head, some def ids passed as `callee_id`s are not body owners. This PR fixes that.

cc `@rust-lang/clippy`

r? `@fee1-dead`

Author: GuillaumeGomez

src/tools/clippy/clippy_lints/src/derive.rs

@@ -451,12 +451,12 @@ fn check_partial_eq_without_eq<'tcx>(cx: &LateContext<'tcx>, span: Span, trait_r
         && let Some(def_id) = trait_ref.trait_def_id()
         && cx.tcx.is_diagnostic_item(sym::PartialEq, def_id)
         && let param_env = param_env_for_derived_eq(cx.tcx, adt.did(), eq_trait_def_id)
-        && !implements_trait_with_env(cx.tcx, param_env, ty, eq_trait_def_id, adt.did(),&[])
+        && !implements_trait_with_env(cx.tcx, param_env, ty, eq_trait_def_id, None, &[])
         // If all of our fields implement `Eq`, we can implement `Eq` too
         && adt
             .all_fields()
             .map(|f| f.ty(cx.tcx, args))
-            .all(|ty| implements_trait_with_env(cx.tcx, param_env, ty, eq_trait_def_id, adt.did(), &[]))
+            .all(|ty| implements_trait_with_env(cx.tcx, param_env, ty, eq_trait_def_id, None, &[]))
     {
         span_lint_and_sugg(
             cx,

src/tools/clippy/clippy_lints/src/loops/explicit_iter_loop.rs

@@ -118,7 +118,7 @@ fn is_ref_iterable<'tcx>(
             .liberate_late_bound_regions(fn_id, cx.tcx.fn_sig(fn_id).skip_binder())
         && let &[req_self_ty, req_res_ty] = &**sig.inputs_and_output
         && let param_env = cx.tcx.param_env(fn_id)
-        && implements_trait_with_env(cx.tcx, param_env, req_self_ty, trait_id, fn_id, &[])
+        && implements_trait_with_env(cx.tcx, param_env, req_self_ty, trait_id, Some(fn_id), &[])
         && let Some(into_iter_ty) =
             make_normalized_projection_with_regions(cx.tcx, param_env, trait_id, sym!(IntoIter), [req_self_ty])
         && let req_res_ty = normalize_with_regions(cx.tcx, param_env, req_res_ty)

src/tools/clippy/clippy_utils/src/ty.rs

@@ -214,36 +214,21 @@ pub fn implements_trait<'tcx>(
     trait_id: DefId,
     args: &[GenericArg<'tcx>],
 ) -> bool {
-    let callee_id = cx
-        .enclosing_body
-        .map(|body| cx.tcx.hir().body_owner(body).owner.to_def_id());
-    implements_trait_with_env_from_iter(
-        cx.tcx,
-        cx.param_env,
-        ty,
-        trait_id,
-        callee_id,
-        args.iter().map(|&x| Some(x)),
-    )
+    implements_trait_with_env_from_iter(cx.tcx, cx.param_env, ty, trait_id, None, args.iter().map(|&x| Some(x)))
 }
 
 /// Same as `implements_trait` but allows using a `ParamEnv` different from the lint context.
+///
+/// The `callee_id` argument is used to determine whether this is a function call in a `const fn` environment, used for checking const traits.
 pub fn implements_trait_with_env<'tcx>(
     tcx: TyCtxt<'tcx>,
     param_env: ParamEnv<'tcx>,
     ty: Ty<'tcx>,
     trait_id: DefId,
-    callee_id: DefId,
+    callee_id: Option<DefId>,
     args: &[GenericArg<'tcx>],
 ) -> bool {
-    implements_trait_with_env_from_iter(
-        tcx,
-        param_env,
-        ty,
-        trait_id,
-        Some(callee_id),
-        args.iter().map(|&x| Some(x)),
-    )
+    implements_trait_with_env_from_iter(tcx, param_env, ty, trait_id, callee_id, args.iter().map(|&x| Some(x)))
 }
 
 /// Same as `implements_trait_from_env` but takes the arguments as an iterator.
@@ -258,6 +243,13 @@ pub fn implements_trait_with_env_from_iter<'tcx>(
     // Clippy shouldn't have infer types
     assert!(!ty.has_infer());
 
+    // If a `callee_id` is passed, then we assert that it is a body owner
+    // through calling `body_owner_kind`, which would panic if the callee
+    // does not have a body.
+    if let Some(callee_id) = callee_id {
+        let _ = tcx.hir().body_owner_kind(callee_id);
+    }
+
     let ty = tcx.erase_regions(ty);
     if ty.has_escaping_bound_vars() {
         return false;