diff --git a/clippy_lints/src/methods/unnecessary_filter_map.rs b/clippy_lints/src/methods/unnecessary_filter_map.rs index ca46da81fa0..33f073e75a6 100644 --- a/clippy_lints/src/methods/unnecessary_filter_map.rs +++ b/clippy_lints/src/methods/unnecessary_filter_map.rs @@ -1,13 +1,15 @@ use super::utils::clone_or_copy_needed; -use clippy_utils::diagnostics::span_lint; +use clippy_utils::diagnostics::span_lint_and_sugg; use clippy_utils::ty::is_copy; use clippy_utils::usage::mutated_variables; use clippy_utils::visitors::{Descend, for_each_expr_without_closures}; -use clippy_utils::{is_res_lang_ctor, is_trait_method, path_res, path_to_local_id}; +use clippy_utils::{MaybePath, is_res_lang_ctor, is_trait_method, path_res, path_to_local_id}; use core::ops::ControlFlow; +use rustc_errors::Applicability; use rustc_hir as hir; use rustc_hir::LangItem::{OptionNone, OptionSome}; use rustc_lint::LateContext; +use rustc_middle::query::Key; use rustc_middle::ty; use rustc_span::sym; @@ -36,9 +38,25 @@ pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'tcx>, a ControlFlow::Continue(Descend::Yes) } }); - let in_ty = cx.typeck_results().node_type(body.params[0].hir_id); let sugg = if !found_filtering { + // Check if the closure is .filter_map(|x| Some(x)) + if name == "filter_map" + && let hir::ExprKind::Call(expr, args) = body.value.kind + && is_res_lang_ctor(cx, path_res(cx, expr), OptionSome) + && arg_id.ty_def_id() == args[0].hir_id().ty_def_id() + && let hir::ExprKind::Path(_) = args[0].kind + { + span_lint_and_sugg( + cx, + UNNECESSARY_FILTER_MAP, + expr.span, + format!("{name} is unnecessary"), + "try removing the filter_map", + String::new(), + Applicability::MaybeIncorrect, + ); + } if name == "filter_map" { "map" } else { "map(..).next()" } } else if !found_mapping && !mutates_arg && (!clone_or_copy_needed || is_copy(cx, in_ty)) { match cx.typeck_results().expr_ty(body.value).kind() { @@ -52,7 +70,7 @@ pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'tcx>, a } else { return; }; - span_lint( + span_lint_and_sugg( cx, if name == "filter_map" { UNNECESSARY_FILTER_MAP @@ -60,7 +78,10 @@ pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'tcx>, a UNNECESSARY_FIND_MAP }, expr.span, - format!("this `.{name}` can be written more simply using `.{sugg}`"), + format!("this `.{name}` can be written more simply"), + format!("try replacing with `.{sugg}`"), + sugg.to_string(), + Applicability::MaybeIncorrect, ); } } diff --git a/tests/ui/unnecessary_filter_map.rs b/tests/ui/unnecessary_filter_map.rs index 1e0d7d12965..8cf102ab0a5 100644 --- a/tests/ui/unnecessary_filter_map.rs +++ b/tests/ui/unnecessary_filter_map.rs @@ -1,26 +1,31 @@ +//@no-rustfix #![allow(dead_code)] fn main() { let _ = (0..4).filter_map(|x| if x > 1 { Some(x) } else { None }); - //~^ ERROR: this `.filter_map` can be written more simply using `.filter` + //~^ ERROR: this `.filter_map` can be written more simply //~| NOTE: `-D clippy::unnecessary-filter-map` implied by `-D warnings` let _ = (0..4).filter_map(|x| { - //~^ ERROR: this `.filter_map` can be written more simply using `.filter` + //~^ ERROR: this `.filter_map` can be written more simply if x > 1 { return Some(x); }; None }); let _ = (0..4).filter_map(|x| match x { - //~^ ERROR: this `.filter_map` can be written more simply using `.filter` + //~^ ERROR: this `.filter_map` can be written more simply 0 | 1 => None, _ => Some(x), }); let _ = (0..4).filter_map(|x| Some(x + 1)); - //~^ ERROR: this `.filter_map` can be written more simply using `.map` + //~^ ERROR: this `.filter_map` can be written more simply let _ = (0..4).filter_map(i32::checked_abs); + + let _ = (0..4).filter_map(Some); + + let _ = vec![Some(10), None].into_iter().filter_map(|x| Some(x)); } fn filter_map_none_changes_item_type() -> impl Iterator { diff --git a/tests/ui/unnecessary_filter_map.stderr b/tests/ui/unnecessary_filter_map.stderr index f32d444ba9e..7ef3d970420 100644 --- a/tests/ui/unnecessary_filter_map.stderr +++ b/tests/ui/unnecessary_filter_map.stderr @@ -1,14 +1,14 @@ -error: this `.filter_map` can be written more simply using `.filter` - --> tests/ui/unnecessary_filter_map.rs:4:13 +error: this `.filter_map` can be written more simply + --> tests/ui/unnecessary_filter_map.rs:5:13 | LL | let _ = (0..4).filter_map(|x| if x > 1 { Some(x) } else { None }); - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try replacing with `.filter`: `filter` | = note: `-D clippy::unnecessary-filter-map` implied by `-D warnings` = help: to override `-D warnings` add `#[allow(clippy::unnecessary_filter_map)]` -error: this `.filter_map` can be written more simply using `.filter` - --> tests/ui/unnecessary_filter_map.rs:7:13 +error: this `.filter_map` can be written more simply + --> tests/ui/unnecessary_filter_map.rs:8:13 | LL | let _ = (0..4).filter_map(|x| { | _____________^ @@ -18,10 +18,10 @@ LL | | return Some(x); LL | | }; LL | | None LL | | }); - | |______^ + | |______^ help: try replacing with `.filter`: `filter` -error: this `.filter_map` can be written more simply using `.filter` - --> tests/ui/unnecessary_filter_map.rs:14:13 +error: this `.filter_map` can be written more simply + --> tests/ui/unnecessary_filter_map.rs:15:13 | LL | let _ = (0..4).filter_map(|x| match x { | _____________^ @@ -29,19 +29,40 @@ LL | | LL | | 0 | 1 => None, LL | | _ => Some(x), LL | | }); - | |______^ + | |______^ help: try replacing with `.filter`: `filter` -error: this `.filter_map` can be written more simply using `.map` - --> tests/ui/unnecessary_filter_map.rs:20:13 +error: this `.filter_map` can be written more simply + --> tests/ui/unnecessary_filter_map.rs:21:13 | LL | let _ = (0..4).filter_map(|x| Some(x + 1)); - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try replacing with `.map`: `map` -error: this `.filter_map` can be written more simply using `.filter` - --> tests/ui/unnecessary_filter_map.rs:160:14 +error: redundant closure + --> tests/ui/unnecessary_filter_map.rs:28:57 + | +LL | let _ = vec![Some(10), None].into_iter().filter_map(|x| Some(x)); + | ^^^^^^^^^^^ help: replace the closure with the function itself: `Some` + | + = note: `-D clippy::redundant-closure` implied by `-D warnings` + = help: to override `-D warnings` add `#[allow(clippy::redundant_closure)]` + +error: filter_map is unnecessary + --> tests/ui/unnecessary_filter_map.rs:28:61 + | +LL | let _ = vec![Some(10), None].into_iter().filter_map(|x| Some(x)); + | ^^^^ help: try removing the filter_map + +error: this `.filter_map` can be written more simply + --> tests/ui/unnecessary_filter_map.rs:28:13 + | +LL | let _ = vec![Some(10), None].into_iter().filter_map(|x| Some(x)); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try replacing with `.map`: `map` + +error: this `.filter_map` can be written more simply + --> tests/ui/unnecessary_filter_map.rs:165:14 | LL | let _x = std::iter::once(1).filter_map(|n| (n > 1).then_some(n)); - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try replacing with `.filter`: `filter` -error: aborting due to 5 previous errors +error: aborting due to 8 previous errors diff --git a/tests/ui/unnecessary_find_map.rs b/tests/ui/unnecessary_find_map.rs index 9972b68092a..c357d853248 100644 --- a/tests/ui/unnecessary_find_map.rs +++ b/tests/ui/unnecessary_find_map.rs @@ -1,24 +1,25 @@ +//@no-rustfix #![allow(dead_code)] fn main() { let _ = (0..4).find_map(|x| if x > 1 { Some(x) } else { None }); - //~^ ERROR: this `.find_map` can be written more simply using `.find` + //~^ ERROR: this `.find_map` can be written more simply //~| NOTE: `-D clippy::unnecessary-find-map` implied by `-D warnings` let _ = (0..4).find_map(|x| { - //~^ ERROR: this `.find_map` can be written more simply using `.find` + //~^ ERROR: this `.find_map` can be written more simply if x > 1 { return Some(x); }; None }); let _ = (0..4).find_map(|x| match x { - //~^ ERROR: this `.find_map` can be written more simply using `.find` + //~^ ERROR: this `.find_map` can be written more simply 0 | 1 => None, _ => Some(x), }); let _ = (0..4).find_map(|x| Some(x + 1)); - //~^ ERROR: this `.find_map` can be written more simply using `.map(..).next()` + //~^ ERROR: this `.find_map` can be written more simply let _ = (0..4).find_map(i32::checked_abs); } diff --git a/tests/ui/unnecessary_find_map.stderr b/tests/ui/unnecessary_find_map.stderr index bb939a99214..650b6d64d35 100644 --- a/tests/ui/unnecessary_find_map.stderr +++ b/tests/ui/unnecessary_find_map.stderr @@ -1,14 +1,14 @@ -error: this `.find_map` can be written more simply using `.find` - --> tests/ui/unnecessary_find_map.rs:4:13 +error: this `.find_map` can be written more simply + --> tests/ui/unnecessary_find_map.rs:5:13 | LL | let _ = (0..4).find_map(|x| if x > 1 { Some(x) } else { None }); - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try replacing with `.find`: `find` | = note: `-D clippy::unnecessary-find-map` implied by `-D warnings` = help: to override `-D warnings` add `#[allow(clippy::unnecessary_find_map)]` -error: this `.find_map` can be written more simply using `.find` - --> tests/ui/unnecessary_find_map.rs:7:13 +error: this `.find_map` can be written more simply + --> tests/ui/unnecessary_find_map.rs:8:13 | LL | let _ = (0..4).find_map(|x| { | _____________^ @@ -18,10 +18,10 @@ LL | | return Some(x); LL | | }; LL | | None LL | | }); - | |______^ + | |______^ help: try replacing with `.find`: `find` -error: this `.find_map` can be written more simply using `.find` - --> tests/ui/unnecessary_find_map.rs:14:13 +error: this `.find_map` can be written more simply + --> tests/ui/unnecessary_find_map.rs:15:13 | LL | let _ = (0..4).find_map(|x| match x { | _____________^ @@ -29,19 +29,19 @@ LL | | LL | | 0 | 1 => None, LL | | _ => Some(x), LL | | }); - | |______^ + | |______^ help: try replacing with `.find`: `find` -error: this `.find_map` can be written more simply using `.map(..).next()` - --> tests/ui/unnecessary_find_map.rs:20:13 +error: this `.find_map` can be written more simply + --> tests/ui/unnecessary_find_map.rs:21:13 | LL | let _ = (0..4).find_map(|x| Some(x + 1)); - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try replacing with `.map(..).next()`: `map(..).next()` -error: this `.find_map` can be written more simply using `.find` - --> tests/ui/unnecessary_find_map.rs:32:14 +error: this `.find_map` can be written more simply + --> tests/ui/unnecessary_find_map.rs:33:14 | LL | let _x = std::iter::once(1).find_map(|n| (n > 1).then_some(n)); - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try replacing with `.find`: `find` error: aborting due to 5 previous errors