diff --git a/clippy_lints/src/useless_conversion.rs b/clippy_lints/src/useless_conversion.rs index ec8af2b8362..64dfe51b059 100644 --- a/clippy_lints/src/useless_conversion.rs +++ b/clippy_lints/src/useless_conversion.rs @@ -40,6 +40,7 @@ declare_clippy_lint! { #[derive(Default)] pub struct UselessConversion { try_desugar_arm: Vec, + expn_depth: u32, } impl_lint_pass!(UselessConversion => [USELESS_CONVERSION]); @@ -102,21 +103,11 @@ fn into_iter_deep_call<'hir>(cx: &LateContext<'_>, mut expr: &'hir Expr<'hir>) - (expr, depth) } -/// Checks if the given `expr` is an argument of a macro invocation. -/// This is a slow-ish operation, so consider calling this late -/// to avoid slowing down the lint in the happy path when not emitting a warning -fn is_macro_argument(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool { - if let Some(parent) = get_parent_expr(cx, expr) { - parent.span.from_expansion() || is_macro_argument(cx, parent) - } else { - false - } -} - #[expect(clippy::too_many_lines)] 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; } @@ -185,7 +176,7 @@ impl<'tcx> LateLintPass<'tcx> for UselessConversion { && 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) - && !is_macro_argument(cx, e) + && self.expn_depth == 0 { // Get the "innermost" `.into_iter()` call, e.g. given this expression: // `foo.into_iter().into_iter()` @@ -321,5 +312,8 @@ impl<'tcx> LateLintPass<'tcx> for UselessConversion { 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/tests/ui/useless_conversion.fixed b/tests/ui/useless_conversion.fixed index d5a57ec61f7..52591959905 100644 --- a/tests/ui/useless_conversion.fixed +++ b/tests/ui/useless_conversion.fixed @@ -153,6 +153,20 @@ 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 = $e; // removing `.into_iter()` leads to a type error here + }; + } + x!(Some(5).into_iter()); +} + #[allow(dead_code)] fn explicit_into_iter_fn_arg() { fn a(_: T) {} diff --git a/tests/ui/useless_conversion.rs b/tests/ui/useless_conversion.rs index 6730e6909c5..befb2f9a5c3 100644 --- a/tests/ui/useless_conversion.rs +++ b/tests/ui/useless_conversion.rs @@ -153,6 +153,20 @@ fn main() { let _ = vec![s4, s4, s4].into_iter().into_iter(); } +#[allow(dead_code)] +fn issue11065_fp() { + use std::option::IntoIter; + fn takes_into_iter(_: impl IntoIterator) {} + + macro_rules! x { + ($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/tests/ui/useless_conversion.stderr b/tests/ui/useless_conversion.stderr index bf701b1e81e..28e7bb61098 100644 --- a/tests/ui/useless_conversion.stderr +++ b/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:169:7 + --> $DIR/useless_conversion.rs:183:7 | 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:159:13 + --> $DIR/useless_conversion.rs:173:13 | LL | fn b>(_: T) {} | ^^^^^^^^^^^^^^^^^^^^^^^^ error: explicit call to `.into_iter()` in function argument accepting `IntoIterator` - --> $DIR/useless_conversion.rs:170:7 + --> $DIR/useless_conversion.rs:184:7 | 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:160:18 + --> $DIR/useless_conversion.rs:174:18 | LL | fn c(_: impl IntoIterator) {} | ^^^^^^^^^^^^^^^^^^^^^^^^ error: explicit call to `.into_iter()` in function argument accepting `IntoIterator` - --> $DIR/useless_conversion.rs:171:7 + --> $DIR/useless_conversion.rs:185:7 | 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:163:12 + --> $DIR/useless_conversion.rs:177:12 | LL | T: IntoIterator, | ^^^^^^^^^^^^^^^^^^^^^^^^ error: explicit call to `.into_iter()` in function argument accepting `IntoIterator` - --> $DIR/useless_conversion.rs:174:7 + --> $DIR/useless_conversion.rs:188:7 | 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:159:13 + --> $DIR/useless_conversion.rs:173:13 | LL | fn b>(_: T) {} | ^^^^^^^^^^^^^^^^^^^^^^^^ error: explicit call to `.into_iter()` in function argument accepting `IntoIterator` - --> $DIR/useless_conversion.rs:175:7 + --> $DIR/useless_conversion.rs:189:7 | 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:159:13 + --> $DIR/useless_conversion.rs:173:13 | LL | fn b>(_: T) {} | ^^^^^^^^^^^^^^^^^^^^^^^^