diff --git a/clippy_utils/src/eager_or_lazy.rs b/clippy_utils/src/eager_or_lazy.rs index e05b88e4cd0..addd3619a84 100644 --- a/clippy_utils/src/eager_or_lazy.rs +++ b/clippy_utils/src/eager_or_lazy.rs @@ -15,6 +15,7 @@ use rustc_hir::intravisit::{walk_expr, Visitor}; use rustc_hir::{def_id::DefId, Block, Expr, ExprKind, QPath, UnOp}; use rustc_lint::LateContext; +use rustc_middle::ty::adjustment::Adjust; use rustc_middle::ty::{self, PredicateKind}; use rustc_span::{sym, Symbol}; use std::cmp; @@ -114,6 +115,20 @@ fn visit_expr(&mut self, e: &'tcx Expr<'_>) { if self.eagerness == ForceNoChange { return; } + + // Autoderef through a user-defined `Deref` impl can have side-effects, + // so don't suggest changing it. + if self + .cx + .typeck_results() + .expr_adjustments(e) + .iter() + .any(|adj| matches!(adj.kind, Adjust::Deref(Some(_)))) + { + self.eagerness |= NoChange; + return; + } + match e.kind { ExprKind::Call( &Expr { diff --git a/tests/ui/unnecessary_lazy_eval.fixed b/tests/ui/unnecessary_lazy_eval.fixed index f8d4c0bd912..565bd96cf30 100644 --- a/tests/ui/unnecessary_lazy_eval.fixed +++ b/tests/ui/unnecessary_lazy_eval.fixed @@ -4,6 +4,7 @@ #![allow(clippy::redundant_closure)] #![allow(clippy::bind_instead_of_map)] #![allow(clippy::map_identity)] +#![allow(clippy::needless_borrow)] use std::ops::Deref; @@ -81,6 +82,9 @@ fn main() { let _ = Some(1).unwrap_or(*r); let b = Box::new(1); let _ = Some(1).unwrap_or(*b); + // Should lint - Builtin deref through autoderef + let _ = Some(1).as_ref().unwrap_or(&r); + let _ = Some(1).as_ref().unwrap_or(&b); // Cases when unwrap is not called on a simple variable let _ = Some(10).unwrap_or(2); @@ -113,6 +117,9 @@ fn main() { let _ = Some(1).unwrap_or_else(|| *Issue10437); // Issue10437 has a deref impl let _ = Some(1).unwrap_or(*Issue10437); + let _ = Some(1).as_ref().unwrap_or_else(|| &Issue10437); + let _ = Some(1).as_ref().unwrap_or(&Issue10437); + // Should not lint - bool let _ = (0 == 1).then(|| Issue9427(0)); // Issue9427 has a significant drop let _ = false.then(|| Issue9427FollowUp); // Issue9427FollowUp has a significant drop diff --git a/tests/ui/unnecessary_lazy_eval.rs b/tests/ui/unnecessary_lazy_eval.rs index b968894f870..3627076b2af 100644 --- a/tests/ui/unnecessary_lazy_eval.rs +++ b/tests/ui/unnecessary_lazy_eval.rs @@ -4,6 +4,7 @@ #![allow(clippy::redundant_closure)] #![allow(clippy::bind_instead_of_map)] #![allow(clippy::map_identity)] +#![allow(clippy::needless_borrow)] use std::ops::Deref; @@ -81,6 +82,9 @@ fn main() { let _ = Some(1).unwrap_or_else(|| *r); let b = Box::new(1); let _ = Some(1).unwrap_or_else(|| *b); + // Should lint - Builtin deref through autoderef + let _ = Some(1).as_ref().unwrap_or_else(|| &r); + let _ = Some(1).as_ref().unwrap_or_else(|| &b); // Cases when unwrap is not called on a simple variable let _ = Some(10).unwrap_or_else(|| 2); @@ -113,6 +117,9 @@ fn main() { let _ = Some(1).unwrap_or_else(|| *Issue10437); // Issue10437 has a deref impl let _ = Some(1).unwrap_or(*Issue10437); + let _ = Some(1).as_ref().unwrap_or_else(|| &Issue10437); + let _ = Some(1).as_ref().unwrap_or(&Issue10437); + // Should not lint - bool let _ = (0 == 1).then(|| Issue9427(0)); // Issue9427 has a significant drop let _ = false.then(|| Issue9427FollowUp); // Issue9427FollowUp has a significant drop diff --git a/tests/ui/unnecessary_lazy_eval.stderr b/tests/ui/unnecessary_lazy_eval.stderr index c3d106cd109..2850a632fc7 100644 --- a/tests/ui/unnecessary_lazy_eval.stderr +++ b/tests/ui/unnecessary_lazy_eval.stderr @@ -1,5 +1,5 @@ error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:67:13 + --> $DIR/unnecessary_lazy_eval.rs:68:13 | LL | let _ = opt.unwrap_or_else(|| 2); | ^^^^-------------------- @@ -9,7 +9,7 @@ LL | let _ = opt.unwrap_or_else(|| 2); = note: `-D clippy::unnecessary-lazy-evaluations` implied by `-D warnings` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:68:13 + --> $DIR/unnecessary_lazy_eval.rs:69:13 | LL | let _ = opt.unwrap_or_else(|| astronomers_pi); | ^^^^--------------------------------- @@ -17,7 +17,7 @@ LL | let _ = opt.unwrap_or_else(|| astronomers_pi); | help: use `unwrap_or(..)` instead: `unwrap_or(astronomers_pi)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:69:13 + --> $DIR/unnecessary_lazy_eval.rs:70:13 | LL | let _ = opt.unwrap_or_else(|| ext_str.some_field); | ^^^^------------------------------------- @@ -25,7 +25,7 @@ LL | let _ = opt.unwrap_or_else(|| ext_str.some_field); | help: use `unwrap_or(..)` instead: `unwrap_or(ext_str.some_field)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:71:13 + --> $DIR/unnecessary_lazy_eval.rs:72:13 | LL | let _ = opt.and_then(|_| ext_opt); | ^^^^--------------------- @@ -33,7 +33,7 @@ LL | let _ = opt.and_then(|_| ext_opt); | help: use `and(..)` instead: `and(ext_opt)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:72:13 + --> $DIR/unnecessary_lazy_eval.rs:73:13 | LL | let _ = opt.or_else(|| ext_opt); | ^^^^------------------- @@ -41,7 +41,7 @@ LL | let _ = opt.or_else(|| ext_opt); | help: use `or(..)` instead: `or(ext_opt)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:73:13 + --> $DIR/unnecessary_lazy_eval.rs:74:13 | LL | let _ = opt.or_else(|| None); | ^^^^---------------- @@ -49,7 +49,7 @@ LL | let _ = opt.or_else(|| None); | help: use `or(..)` instead: `or(None)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:74:13 + --> $DIR/unnecessary_lazy_eval.rs:75:13 | LL | let _ = opt.get_or_insert_with(|| 2); | ^^^^------------------------ @@ -57,7 +57,7 @@ LL | let _ = opt.get_or_insert_with(|| 2); | help: use `get_or_insert(..)` instead: `get_or_insert(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:75:13 + --> $DIR/unnecessary_lazy_eval.rs:76:13 | LL | let _ = opt.ok_or_else(|| 2); | ^^^^---------------- @@ -65,7 +65,7 @@ LL | let _ = opt.ok_or_else(|| 2); | help: use `ok_or(..)` instead: `ok_or(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:76:13 + --> $DIR/unnecessary_lazy_eval.rs:77:13 | LL | let _ = nested_tuple_opt.unwrap_or_else(|| Some((1, 2))); | ^^^^^^^^^^^^^^^^^------------------------------- @@ -73,7 +73,7 @@ LL | let _ = nested_tuple_opt.unwrap_or_else(|| Some((1, 2))); | help: use `unwrap_or(..)` instead: `unwrap_or(Some((1, 2)))` error: unnecessary closure used with `bool::then` - --> $DIR/unnecessary_lazy_eval.rs:77:13 + --> $DIR/unnecessary_lazy_eval.rs:78:13 | LL | let _ = cond.then(|| astronomers_pi); | ^^^^^----------------------- @@ -81,7 +81,7 @@ LL | let _ = cond.then(|| astronomers_pi); | help: use `then_some(..)` instead: `then_some(astronomers_pi)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:81:13 + --> $DIR/unnecessary_lazy_eval.rs:82:13 | LL | let _ = Some(1).unwrap_or_else(|| *r); | ^^^^^^^^--------------------- @@ -89,7 +89,7 @@ LL | let _ = Some(1).unwrap_or_else(|| *r); | help: use `unwrap_or(..)` instead: `unwrap_or(*r)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:83:13 + --> $DIR/unnecessary_lazy_eval.rs:84:13 | LL | let _ = Some(1).unwrap_or_else(|| *b); | ^^^^^^^^--------------------- @@ -99,13 +99,29 @@ LL | let _ = Some(1).unwrap_or_else(|| *b); error: unnecessary closure used to substitute value for `Option::None` --> $DIR/unnecessary_lazy_eval.rs:86:13 | +LL | let _ = Some(1).as_ref().unwrap_or_else(|| &r); + | ^^^^^^^^^^^^^^^^^--------------------- + | | + | help: use `unwrap_or(..)` instead: `unwrap_or(&r)` + +error: unnecessary closure used to substitute value for `Option::None` + --> $DIR/unnecessary_lazy_eval.rs:87:13 + | +LL | let _ = Some(1).as_ref().unwrap_or_else(|| &b); + | ^^^^^^^^^^^^^^^^^--------------------- + | | + | help: use `unwrap_or(..)` instead: `unwrap_or(&b)` + +error: unnecessary closure used to substitute value for `Option::None` + --> $DIR/unnecessary_lazy_eval.rs:90:13 + | LL | let _ = Some(10).unwrap_or_else(|| 2); | ^^^^^^^^^-------------------- | | | help: use `unwrap_or(..)` instead: `unwrap_or(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:87:13 + --> $DIR/unnecessary_lazy_eval.rs:91:13 | LL | let _ = Some(10).and_then(|_| ext_opt); | ^^^^^^^^^--------------------- @@ -113,7 +129,7 @@ LL | let _ = Some(10).and_then(|_| ext_opt); | help: use `and(..)` instead: `and(ext_opt)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:88:28 + --> $DIR/unnecessary_lazy_eval.rs:92:28 | LL | let _: Option = None.or_else(|| ext_opt); | ^^^^^------------------- @@ -121,7 +137,7 @@ LL | let _: Option = None.or_else(|| ext_opt); | help: use `or(..)` instead: `or(ext_opt)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:89:13 + --> $DIR/unnecessary_lazy_eval.rs:93:13 | LL | let _ = None.get_or_insert_with(|| 2); | ^^^^^------------------------ @@ -129,7 +145,7 @@ LL | let _ = None.get_or_insert_with(|| 2); | help: use `get_or_insert(..)` instead: `get_or_insert(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:90:35 + --> $DIR/unnecessary_lazy_eval.rs:94:35 | LL | let _: Result = None.ok_or_else(|| 2); | ^^^^^---------------- @@ -137,7 +153,7 @@ LL | let _: Result = None.ok_or_else(|| 2); | help: use `ok_or(..)` instead: `ok_or(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:91:28 + --> $DIR/unnecessary_lazy_eval.rs:95:28 | LL | let _: Option = None.or_else(|| None); | ^^^^^---------------- @@ -145,7 +161,7 @@ LL | let _: Option = None.or_else(|| None); | help: use `or(..)` instead: `or(None)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:94:13 + --> $DIR/unnecessary_lazy_eval.rs:98:13 | LL | let _ = deep.0.unwrap_or_else(|| 2); | ^^^^^^^-------------------- @@ -153,7 +169,7 @@ LL | let _ = deep.0.unwrap_or_else(|| 2); | help: use `unwrap_or(..)` instead: `unwrap_or(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:95:13 + --> $DIR/unnecessary_lazy_eval.rs:99:13 | LL | let _ = deep.0.and_then(|_| ext_opt); | ^^^^^^^--------------------- @@ -161,7 +177,7 @@ LL | let _ = deep.0.and_then(|_| ext_opt); | help: use `and(..)` instead: `and(ext_opt)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:96:13 + --> $DIR/unnecessary_lazy_eval.rs:100:13 | LL | let _ = deep.0.or_else(|| None); | ^^^^^^^---------------- @@ -169,7 +185,7 @@ LL | let _ = deep.0.or_else(|| None); | help: use `or(..)` instead: `or(None)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:97:13 + --> $DIR/unnecessary_lazy_eval.rs:101:13 | LL | let _ = deep.0.get_or_insert_with(|| 2); | ^^^^^^^------------------------ @@ -177,7 +193,7 @@ LL | let _ = deep.0.get_or_insert_with(|| 2); | help: use `get_or_insert(..)` instead: `get_or_insert(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:98:13 + --> $DIR/unnecessary_lazy_eval.rs:102:13 | LL | let _ = deep.0.ok_or_else(|| 2); | ^^^^^^^---------------- @@ -185,7 +201,7 @@ LL | let _ = deep.0.ok_or_else(|| 2); | help: use `ok_or(..)` instead: `ok_or(2)` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:125:28 + --> $DIR/unnecessary_lazy_eval.rs:132:28 | LL | let _: Option = None.or_else(|| Some(3)); | ^^^^^------------------- @@ -193,7 +209,7 @@ LL | let _: Option = None.or_else(|| Some(3)); | help: use `or(..)` instead: `or(Some(3))` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:126:13 + --> $DIR/unnecessary_lazy_eval.rs:133:13 | LL | let _ = deep.0.or_else(|| Some(3)); | ^^^^^^^------------------- @@ -201,7 +217,7 @@ LL | let _ = deep.0.or_else(|| Some(3)); | help: use `or(..)` instead: `or(Some(3))` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:127:13 + --> $DIR/unnecessary_lazy_eval.rs:134:13 | LL | let _ = opt.or_else(|| Some(3)); | ^^^^------------------- @@ -209,7 +225,7 @@ LL | let _ = opt.or_else(|| Some(3)); | help: use `or(..)` instead: `or(Some(3))` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:133:13 + --> $DIR/unnecessary_lazy_eval.rs:140:13 | LL | let _ = res2.unwrap_or_else(|_| 2); | ^^^^^--------------------- @@ -217,7 +233,7 @@ LL | let _ = res2.unwrap_or_else(|_| 2); | help: use `unwrap_or(..)` instead: `unwrap_or(2)` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:134:13 + --> $DIR/unnecessary_lazy_eval.rs:141:13 | LL | let _ = res2.unwrap_or_else(|_| astronomers_pi); | ^^^^^---------------------------------- @@ -225,7 +241,7 @@ LL | let _ = res2.unwrap_or_else(|_| astronomers_pi); | help: use `unwrap_or(..)` instead: `unwrap_or(astronomers_pi)` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:135:13 + --> $DIR/unnecessary_lazy_eval.rs:142:13 | LL | let _ = res2.unwrap_or_else(|_| ext_str.some_field); | ^^^^^-------------------------------------- @@ -233,7 +249,7 @@ LL | let _ = res2.unwrap_or_else(|_| ext_str.some_field); | help: use `unwrap_or(..)` instead: `unwrap_or(ext_str.some_field)` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:157:35 + --> $DIR/unnecessary_lazy_eval.rs:164:35 | LL | let _: Result = res.and_then(|_| Err(2)); | ^^^^-------------------- @@ -241,7 +257,7 @@ LL | let _: Result = res.and_then(|_| Err(2)); | help: use `and(..)` instead: `and(Err(2))` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:158:35 + --> $DIR/unnecessary_lazy_eval.rs:165:35 | LL | let _: Result = res.and_then(|_| Err(astronomers_pi)); | ^^^^--------------------------------- @@ -249,7 +265,7 @@ LL | let _: Result = res.and_then(|_| Err(astronomers_pi)); | help: use `and(..)` instead: `and(Err(astronomers_pi))` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:159:35 + --> $DIR/unnecessary_lazy_eval.rs:166:35 | LL | let _: Result = res.and_then(|_| Err(ext_str.some_field)); | ^^^^------------------------------------- @@ -257,7 +273,7 @@ LL | let _: Result = res.and_then(|_| Err(ext_str.some_field)) | help: use `and(..)` instead: `and(Err(ext_str.some_field))` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:161:35 + --> $DIR/unnecessary_lazy_eval.rs:168:35 | LL | let _: Result = res.or_else(|_| Ok(2)); | ^^^^------------------ @@ -265,7 +281,7 @@ LL | let _: Result = res.or_else(|_| Ok(2)); | help: use `or(..)` instead: `or(Ok(2))` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:162:35 + --> $DIR/unnecessary_lazy_eval.rs:169:35 | LL | let _: Result = res.or_else(|_| Ok(astronomers_pi)); | ^^^^------------------------------- @@ -273,7 +289,7 @@ LL | let _: Result = res.or_else(|_| Ok(astronomers_pi)); | help: use `or(..)` instead: `or(Ok(astronomers_pi))` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:163:35 + --> $DIR/unnecessary_lazy_eval.rs:170:35 | LL | let _: Result = res.or_else(|_| Ok(ext_str.some_field)); | ^^^^----------------------------------- @@ -281,7 +297,7 @@ LL | let _: Result = res.or_else(|_| Ok(ext_str.some_field)); | help: use `or(..)` instead: `or(Ok(ext_str.some_field))` error: unnecessary closure used to substitute value for `Result::Err` - --> $DIR/unnecessary_lazy_eval.rs:164:35 + --> $DIR/unnecessary_lazy_eval.rs:171:35 | LL | let _: Result = res. | ___________________________________^ @@ -295,5 +311,5 @@ LL | | or_else(|_| Ok(ext_str.some_field)); | | | help: use `or(..)` instead: `or(Ok(ext_str.some_field))` -error: aborting due to 36 previous errors +error: aborting due to 38 previous errors