From 09d05c04da516d4f54ccf41e22b544bc8c425373 Mon Sep 17 00:00:00 2001 From: bors Date: Thu, 17 Aug 2023 14:41:46 +0000 Subject: [PATCH 1/2] Auto merge of #11070 - y21:issue11065, r=flip1995 [`useless_conversion`]: only lint on paths to fn items and fix FP in macro Fixes #11065 (which is actually two issues: an ICE and a false positive) It now makes sure that the function call path points to a function-like item (and not e.g. a `const` like in the linked issue), so that calling `TyCtxt::fn_sig` later in the lint does not ICE (fixes https://github.com/rust-lang/rust-clippy/issues/11065#issuecomment-1616836099). It *also* makes sure that the expression is not part of a macro call (fixes https://github.com/rust-lang/rust-clippy/issues/11065#issuecomment-1616919639). ~~I'm not sure if there's a better way to check this other than to walk the parent expr chain and see if any of them are expansions.~~ (edit: it doesn't do this anymore) changelog: [`useless_conversion`]: fix ICE when call receiver is a non-fn item changelog: [`useless_conversion`]: don't lint if argument is a macro argument (fixes a FP) r? `@llogiq` (reviewed #10814, which introduced these issues) --- .../clippy_lints/src/useless_conversion.rs | 18 ++++++++++++++--- .../clippy/tests/ui/crashes/ice-11065.rs | 19 ++++++++++++++++++ .../clippy/tests/ui/useless_conversion.fixed | 14 +++++++++++++ .../clippy/tests/ui/useless_conversion.rs | 14 +++++++++++++ .../clippy/tests/ui/useless_conversion.stderr | 20 +++++++++---------- 5 files changed, 72 insertions(+), 13 deletions(-) create mode 100644 src/tools/clippy/tests/ui/crashes/ice-11065.rs diff --git a/src/tools/clippy/clippy_lints/src/useless_conversion.rs b/src/tools/clippy/clippy_lints/src/useless_conversion.rs index bd4dc07a42b..5ac4f0aa46c 100644 --- a/src/tools/clippy/clippy_lints/src/useless_conversion.rs +++ b/src/tools/clippy/clippy_lints/src/useless_conversion.rs @@ -5,6 +5,7 @@ use clippy_utils::{get_parent_expr, is_trait_method, is_ty_alias, match_def_path, path_to_local, paths}; use if_chain::if_chain; use rustc_errors::Applicability; +use rustc_hir::def::DefKind; use rustc_hir::def_id::DefId; use rustc_hir::{BindingAnnotation, Expr, ExprKind, HirId, MatchSource, Node, PatKind}; use rustc_lint::{LateContext, LateLintPass}; @@ -39,6 +40,7 @@ #[derive(Default)] pub struct UselessConversion { try_desugar_arm: Vec, + expn_depth: u32, } impl_lint_pass!(UselessConversion => [USELESS_CONVERSION]); @@ -105,6 +107,7 @@ fn into_iter_deep_call<'hir>(cx: &LateContext<'_>, mut expr: &'hir Expr<'hir>) - impl<'tcx> LateLintPass<'tcx> for UselessConversion { fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) { if e.span.from_expansion() { + self.expn_depth += 1; return; } @@ -150,9 +153,14 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) { { if let Some(parent) = get_parent_expr(cx, e) { let parent_fn = match parent.kind { - ExprKind::Call(recv, args) if let ExprKind::Path(ref qpath) = recv.kind => { - cx.qpath_res(qpath, recv.hir_id).opt_def_id() - .map(|did| (did, args, MethodOrFunction::Function)) + ExprKind::Call(recv, args) + if let ExprKind::Path(ref qpath) = recv.kind + && let Some(did) = cx.qpath_res(qpath, recv.hir_id).opt_def_id() + // make sure that the path indeed points to a fn-like item, so that + // `fn_sig` does not ICE. (see #11065) + && cx.tcx.opt_def_kind(did).is_some_and(DefKind::is_fn_like) => + { + Some((did, args, MethodOrFunction::Function)) } ExprKind::MethodCall(.., args, _) => { cx.typeck_results().type_dependent_def_id(parent.hir_id) @@ -168,6 +176,7 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) { && let Some(&into_iter_param) = sig.inputs().get(kind.param_pos(arg_pos)) && let ty::Param(param) = into_iter_param.kind() && let Some(span) = into_iter_bound(cx, parent_fn_did, into_iter_did, param.index) + && self.expn_depth == 0 { // Get the "innermost" `.into_iter()` call, e.g. given this expression: // `foo.into_iter().into_iter()` @@ -303,5 +312,8 @@ fn check_expr_post(&mut self, _: &LateContext<'tcx>, e: &'tcx Expr<'_>) { if Some(&e.hir_id) == self.try_desugar_arm.last() { self.try_desugar_arm.pop(); } + if e.span.from_expansion() { + self.expn_depth -= 1; + } } } diff --git a/src/tools/clippy/tests/ui/crashes/ice-11065.rs b/src/tools/clippy/tests/ui/crashes/ice-11065.rs new file mode 100644 index 00000000000..f5cf6b1cd77 --- /dev/null +++ b/src/tools/clippy/tests/ui/crashes/ice-11065.rs @@ -0,0 +1,19 @@ +#![warn(clippy::useless_conversion)] + +use std::iter::FromIterator; +use std::option::IntoIter as OptionIter; + +fn eq(a: T, b: T) -> bool { + a == b +} + +macro_rules! tests { + ($($expr:expr, $ty:ty, ($($test:expr),*);)+) => (pub fn main() {$({ + const C: $ty = $expr; + assert!(eq(C($($test),*), $expr($($test),*))); + })+}) +} + +tests! { + FromIterator::from_iter, fn(OptionIter) -> Vec, (Some(5).into_iter()); +} diff --git a/src/tools/clippy/tests/ui/useless_conversion.fixed b/src/tools/clippy/tests/ui/useless_conversion.fixed index 5d2c5b11658..53d8a5a9ff1 100644 --- a/src/tools/clippy/tests/ui/useless_conversion.fixed +++ b/src/tools/clippy/tests/ui/useless_conversion.fixed @@ -155,6 +155,20 @@ fn main() { let _ = vec![s4, s4, s4].into_iter(); } +#[allow(dead_code)] +fn issue11065_fp() { + use std::option::IntoIter; + fn takes_into_iter(_: impl IntoIterator) {} + + macro_rules! x { + ($e:expr) => { + takes_into_iter($e); + let _: IntoIter = $e; // removing `.into_iter()` leads to a type error here + }; + } + x!(Some(5).into_iter()); +} + #[allow(dead_code)] fn explicit_into_iter_fn_arg() { fn a(_: T) {} diff --git a/src/tools/clippy/tests/ui/useless_conversion.rs b/src/tools/clippy/tests/ui/useless_conversion.rs index 03a3e3f95ba..51ba4987339 100644 --- a/src/tools/clippy/tests/ui/useless_conversion.rs +++ b/src/tools/clippy/tests/ui/useless_conversion.rs @@ -155,6 +155,20 @@ fn main() { let _ = vec![s4, s4, s4].into_iter().into_iter(); } +#[allow(dead_code)] +fn issue11065_fp() { + use std::option::IntoIter; + fn takes_into_iter(_: impl IntoIterator) {} + + macro_rules! x { + ($e:expr) => { + takes_into_iter($e); + let _: IntoIter = $e; // removing `.into_iter()` leads to a type error here + }; + } + x!(Some(5).into_iter()); +} + #[allow(dead_code)] fn explicit_into_iter_fn_arg() { fn a(_: T) {} diff --git a/src/tools/clippy/tests/ui/useless_conversion.stderr b/src/tools/clippy/tests/ui/useless_conversion.stderr index 4957f73a469..6f7dc01d2cd 100644 --- a/src/tools/clippy/tests/ui/useless_conversion.stderr +++ b/src/tools/clippy/tests/ui/useless_conversion.stderr @@ -119,61 +119,61 @@ LL | let _ = vec![s4, s4, s4].into_iter().into_iter(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider removing `.into_iter()`: `vec![s4, s4, s4].into_iter()` error: explicit call to `.into_iter()` in function argument accepting `IntoIterator` - --> $DIR/useless_conversion.rs:171:7 + --> $DIR/useless_conversion.rs:185:7 | LL | b(vec![1, 2].into_iter()); | ^^^^^^^^^^^^^^^^^^^^^^ help: consider removing the `.into_iter()`: `vec![1, 2]` | note: this parameter accepts any `IntoIterator`, so you don't need to call `.into_iter()` - --> $DIR/useless_conversion.rs:161:13 + --> $DIR/useless_conversion.rs:175:13 | LL | fn b>(_: T) {} | ^^^^^^^^^^^^^^^^^^^^^^^^ error: explicit call to `.into_iter()` in function argument accepting `IntoIterator` - --> $DIR/useless_conversion.rs:172:7 + --> $DIR/useless_conversion.rs:186:7 | LL | c(vec![1, 2].into_iter()); | ^^^^^^^^^^^^^^^^^^^^^^ help: consider removing the `.into_iter()`: `vec![1, 2]` | note: this parameter accepts any `IntoIterator`, so you don't need to call `.into_iter()` - --> $DIR/useless_conversion.rs:162:18 + --> $DIR/useless_conversion.rs:176:18 | LL | fn c(_: impl IntoIterator) {} | ^^^^^^^^^^^^^^^^^^^^^^^^ error: explicit call to `.into_iter()` in function argument accepting `IntoIterator` - --> $DIR/useless_conversion.rs:173:7 + --> $DIR/useless_conversion.rs:187:7 | LL | d(vec![1, 2].into_iter()); | ^^^^^^^^^^^^^^^^^^^^^^ help: consider removing the `.into_iter()`: `vec![1, 2]` | note: this parameter accepts any `IntoIterator`, so you don't need to call `.into_iter()` - --> $DIR/useless_conversion.rs:165:12 + --> $DIR/useless_conversion.rs:179:12 | LL | T: IntoIterator, | ^^^^^^^^^^^^^^^^^^^^^^^^ error: explicit call to `.into_iter()` in function argument accepting `IntoIterator` - --> $DIR/useless_conversion.rs:176:7 + --> $DIR/useless_conversion.rs:190:7 | LL | b(vec![1, 2].into_iter().into_iter()); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider removing the `.into_iter()`s: `vec![1, 2]` | note: this parameter accepts any `IntoIterator`, so you don't need to call `.into_iter()` - --> $DIR/useless_conversion.rs:161:13 + --> $DIR/useless_conversion.rs:175:13 | LL | fn b>(_: T) {} | ^^^^^^^^^^^^^^^^^^^^^^^^ error: explicit call to `.into_iter()` in function argument accepting `IntoIterator` - --> $DIR/useless_conversion.rs:177:7 + --> $DIR/useless_conversion.rs:191:7 | LL | b(vec![1, 2].into_iter().into_iter().into_iter()); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider removing the `.into_iter()`s: `vec![1, 2]` | note: this parameter accepts any `IntoIterator`, so you don't need to call `.into_iter()` - --> $DIR/useless_conversion.rs:161:13 + --> $DIR/useless_conversion.rs:175:13 | LL | fn b>(_: T) {} | ^^^^^^^^^^^^^^^^^^^^^^^^ From ff89efeda2c905575665de2bd87d546d208b8195 Mon Sep 17 00:00:00 2001 From: bors Date: Thu, 17 Aug 2023 15:55:23 +0000 Subject: [PATCH 2/2] Auto merge of #11314 - GuillaumeGomez:needless_ref_mut_async_block, r=Centri3 Correctly handle async blocks for NEEDLESS_PASS_BY_REF_MUT Fixes https://github.com/rust-lang/rust-clippy/issues/11299. The problem was that the `async block`s are popping a closure which we didn't go into, making it miss the mutable access to the variables. cc `@Centri3` changelog: none --- .../src/needless_pass_by_ref_mut.rs | 103 ++++++++++++++---- .../tests/ui/needless_pass_by_ref_mut.rs | 35 ++++++ .../tests/ui/needless_pass_by_ref_mut.stderr | 14 ++- 3 files changed, 129 insertions(+), 23 deletions(-) diff --git a/src/tools/clippy/clippy_lints/src/needless_pass_by_ref_mut.rs b/src/tools/clippy/clippy_lints/src/needless_pass_by_ref_mut.rs index c634de960d1..7b00eabf97b 100644 --- a/src/tools/clippy/clippy_lints/src/needless_pass_by_ref_mut.rs +++ b/src/tools/clippy/clippy_lints/src/needless_pass_by_ref_mut.rs @@ -5,14 +5,16 @@ use rustc_data_structures::fx::{FxHashSet, FxIndexMap}; use rustc_errors::Applicability; use rustc_hir::intravisit::{walk_qpath, FnKind, Visitor}; -use rustc_hir::{Body, ExprKind, FnDecl, HirId, HirIdMap, HirIdSet, Impl, ItemKind, Mutability, Node, PatKind, QPath}; +use rustc_hir::{ + Body, Closure, Expr, ExprKind, FnDecl, HirId, HirIdMap, HirIdSet, Impl, ItemKind, Mutability, Node, PatKind, QPath, +}; use rustc_hir_typeck::expr_use_visitor as euv; use rustc_infer::infer::TyCtxtInferExt; use rustc_lint::{LateContext, LateLintPass}; use rustc_middle::hir::map::associated_body; use rustc_middle::hir::nested_filter::OnlyBodies; use rustc_middle::mir::FakeReadCause; -use rustc_middle::ty::{self, Ty, UpvarId, UpvarPath}; +use rustc_middle::ty::{self, Ty, TyCtxt, UpvarId, UpvarPath}; use rustc_session::{declare_tool_lint, impl_lint_pass}; use rustc_span::def_id::LocalDefId; use rustc_span::symbol::kw; @@ -147,22 +149,36 @@ fn check_fn( // Collect variables mutably used and spans which will need dereferencings from the // function body. let MutablyUsedVariablesCtxt { mutably_used_vars, .. } = { - let mut ctx = MutablyUsedVariablesCtxt::default(); + let mut ctx = MutablyUsedVariablesCtxt { + mutably_used_vars: HirIdSet::default(), + prev_bind: None, + prev_move_to_closure: HirIdSet::default(), + aliases: HirIdMap::default(), + async_closures: FxHashSet::default(), + tcx: cx.tcx, + }; let infcx = cx.tcx.infer_ctxt().build(); euv::ExprUseVisitor::new(&mut ctx, &infcx, fn_def_id, cx.param_env, cx.typeck_results()).consume_body(body); if is_async { - let closures = ctx.async_closures.clone(); - let hir = cx.tcx.hir(); - for closure in closures { - ctx.prev_bind = None; - ctx.prev_move_to_closure.clear(); - if let Some(body) = hir - .find_by_def_id(closure) - .and_then(associated_body) - .map(|(_, body_id)| hir.body(body_id)) - { - euv::ExprUseVisitor::new(&mut ctx, &infcx, closure, cx.param_env, cx.typeck_results()) - .consume_body(body); + let mut checked_closures = FxHashSet::default(); + while !ctx.async_closures.is_empty() { + let closures = ctx.async_closures.clone(); + ctx.async_closures.clear(); + let hir = cx.tcx.hir(); + for closure in closures { + if !checked_closures.insert(closure) { + continue; + } + ctx.prev_bind = None; + ctx.prev_move_to_closure.clear(); + if let Some(body) = hir + .find_by_def_id(closure) + .and_then(associated_body) + .map(|(_, body_id)| hir.body(body_id)) + { + euv::ExprUseVisitor::new(&mut ctx, &infcx, closure, cx.param_env, cx.typeck_results()) + .consume_body(body); + } } } } @@ -225,16 +241,16 @@ fn check_crate_post(&mut self, cx: &LateContext<'tcx>) { } } -#[derive(Default)] -struct MutablyUsedVariablesCtxt { +struct MutablyUsedVariablesCtxt<'tcx> { mutably_used_vars: HirIdSet, prev_bind: Option, prev_move_to_closure: HirIdSet, aliases: HirIdMap, async_closures: FxHashSet, + tcx: TyCtxt<'tcx>, } -impl MutablyUsedVariablesCtxt { +impl<'tcx> MutablyUsedVariablesCtxt<'tcx> { fn add_mutably_used_var(&mut self, mut used_id: HirId) { while let Some(id) = self.aliases.get(&used_id) { self.mutably_used_vars.insert(used_id); @@ -242,9 +258,27 @@ fn add_mutably_used_var(&mut self, mut used_id: HirId) { } self.mutably_used_vars.insert(used_id); } + + fn would_be_alias_cycle(&self, alias: HirId, mut target: HirId) -> bool { + while let Some(id) = self.aliases.get(&target) { + if *id == alias { + return true; + } + target = *id; + } + false + } + + fn add_alias(&mut self, alias: HirId, target: HirId) { + // This is to prevent alias loop. + if alias == target || self.would_be_alias_cycle(alias, target) { + return; + } + self.aliases.insert(alias, target); + } } -impl<'tcx> euv::Delegate<'tcx> for MutablyUsedVariablesCtxt { +impl<'tcx> euv::Delegate<'tcx> for MutablyUsedVariablesCtxt<'tcx> { fn consume(&mut self, cmt: &euv::PlaceWithHirId<'tcx>, _id: HirId) { if let euv::Place { base: @@ -259,7 +293,7 @@ fn consume(&mut self, cmt: &euv::PlaceWithHirId<'tcx>, _id: HirId) { { if let Some(bind_id) = self.prev_bind.take() { if bind_id != *vid { - self.aliases.insert(bind_id, *vid); + self.add_alias(bind_id, *vid); } } else if !self.prev_move_to_closure.contains(vid) && matches!(base_ty.ref_mutability(), Some(Mutability::Mut)) @@ -289,6 +323,25 @@ fn borrow(&mut self, cmt: &euv::PlaceWithHirId<'tcx>, _id: HirId, borrow: ty::Bo { self.add_mutably_used_var(*vid); } + } else if borrow == ty::ImmBorrow { + // If there is an `async block`, it'll contain a call to a closure which we need to + // go into to ensure all "mutate" checks are found. + if let Node::Expr(Expr { + kind: + ExprKind::Call( + _, + [ + Expr { + kind: ExprKind::Closure(Closure { def_id, .. }), + .. + }, + ], + ), + .. + }) = self.tcx.hir().get(cmt.hir_id) + { + self.async_closures.insert(*def_id); + } } } @@ -296,7 +349,12 @@ fn mutate(&mut self, cmt: &euv::PlaceWithHirId<'tcx>, _id: HirId) { self.prev_bind = None; if let euv::Place { projections, - base: euv::PlaceBase::Local(vid), + base: + euv::PlaceBase::Local(vid) + | euv::PlaceBase::Upvar(UpvarId { + var_path: UpvarPath { hir_id: vid }, + .. + }), .. } = &cmt.place { @@ -329,8 +387,9 @@ fn fake_read( // Seems like we are inside an async function. We need to store the closure `DefId` // to go through it afterwards. self.async_closures.insert(inner); - self.aliases.insert(cmt.hir_id, *vid); + self.add_alias(cmt.hir_id, *vid); self.prev_move_to_closure.insert(*vid); + self.prev_bind = None; } } } diff --git a/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.rs b/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.rs index ae7b018d0e2..ec87d447597 100644 --- a/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.rs +++ b/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.rs @@ -196,6 +196,41 @@ fn cfg_warn(s: &mut u32) {} //~| NOTE: this is cfg-gated and may require further changes } +// Should not warn. +async fn inner_async(x: &mut i32, y: &mut u32) { + async { + *y += 1; + *x += 1; + } + .await; +} + +async fn inner_async2(x: &mut i32, y: &mut u32) { + //~^ ERROR: this argument is a mutable reference, but not used mutably + async { + *x += 1; + } + .await; +} + +async fn inner_async3(x: &mut i32, y: &mut u32) { + //~^ ERROR: this argument is a mutable reference, but not used mutably + async { + *y += 1; + } + .await; +} + +// Should not warn. +async fn async_vec(b: &mut Vec) { + b.append(&mut vec![]); +} + +// Should not warn. +async fn async_vec2(b: &mut Vec) { + b.push(true); +} + fn main() { let mut u = 0; let mut v = vec![0]; diff --git a/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.stderr b/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.stderr index 0d426ce32f9..2e06e7252d9 100644 --- a/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.stderr +++ b/src/tools/clippy/tests/ui/needless_pass_by_ref_mut.stderr @@ -94,5 +94,17 @@ LL | fn cfg_warn(s: &mut u32) {} | = note: this is cfg-gated and may require further changes -error: aborting due to 15 previous errors +error: this argument is a mutable reference, but not used mutably + --> $DIR/needless_pass_by_ref_mut.rs:208:39 + | +LL | async fn inner_async2(x: &mut i32, y: &mut u32) { + | ^^^^^^^^ help: consider changing to: `&u32` + +error: this argument is a mutable reference, but not used mutably + --> $DIR/needless_pass_by_ref_mut.rs:216:26 + | +LL | async fn inner_async3(x: &mut i32, y: &mut u32) { + | ^^^^^^^^ help: consider changing to: `&i32` + +error: aborting due to 17 previous errors