From c9d2961100317b6ee890fe9116ff3750e6beb6fe Mon Sep 17 00:00:00 2001 From: y21 <30553356+y21@users.noreply.github.com> Date: Thu, 22 Jun 2023 00:56:15 +0200 Subject: [PATCH] teach `eager_or_lazy` that arithmetic ops can panic --- clippy_utils/src/consts.rs | 132 +++++++++++++++++++----- clippy_utils/src/eager_or_lazy.rs | 40 +++++++- tests/ui/unnecessary_lazy_eval.fixed | 46 +++++++++ tests/ui/unnecessary_lazy_eval.rs | 46 +++++++++ tests/ui/unnecessary_lazy_eval.stderr | 138 ++++++++++++++++++-------- 5 files changed, 336 insertions(+), 66 deletions(-) diff --git a/clippy_utils/src/consts.rs b/clippy_utils/src/consts.rs index b7d8c0a8fd73..dc64ba3ee10d 100644 --- a/clippy_utils/src/consts.rs +++ b/clippy_utils/src/consts.rs @@ -10,7 +10,7 @@ use rustc_hir::{BinOp, BinOpKind, Block, ConstBlock, Expr, ExprKind, HirId, Item use rustc_lexer::tokenize; use rustc_lint::LateContext; use rustc_middle::mir::interpret::{alloc_range, Scalar}; -use rustc_middle::ty::{self, EarlyBinder, FloatTy, GenericArgsRef, List, ScalarInt, Ty, TyCtxt}; +use rustc_middle::ty::{self, EarlyBinder, FloatTy, GenericArgsRef, IntTy, List, ScalarInt, Ty, TyCtxt, UintTy}; use rustc_middle::{bug, mir, span_bug}; use rustc_span::symbol::{Ident, Symbol}; use rustc_span::SyntaxContext; @@ -51,6 +51,63 @@ pub enum Constant<'tcx> { Err, } +trait IntTypeBounds: Sized { + type Output: PartialOrd; + + fn min_max(self) -> Option<(Self::Output, Self::Output)>; + fn bits(self) -> Self::Output; + fn ensure_fits(self, val: Self::Output) -> Option { + let (min, max) = self.min_max()?; + (min <= val && val <= max).then_some(val) + } +} +impl IntTypeBounds for UintTy { + type Output = u128; + fn min_max(self) -> Option<(Self::Output, Self::Output)> { + Some(match self { + UintTy::U8 => (u8::MIN.into(), u8::MAX.into()), + UintTy::U16 => (u16::MIN.into(), u16::MAX.into()), + UintTy::U32 => (u32::MIN.into(), u32::MAX.into()), + UintTy::U64 => (u64::MIN.into(), u64::MAX.into()), + UintTy::U128 => (u128::MIN, u128::MAX), + UintTy::Usize => (usize::MIN.try_into().ok()?, usize::MAX.try_into().ok()?), + }) + } + fn bits(self) -> Self::Output { + match self { + UintTy::U8 => 8, + UintTy::U16 => 16, + UintTy::U32 => 32, + UintTy::U64 => 64, + UintTy::U128 => 128, + UintTy::Usize => usize::BITS.into(), + } + } +} +impl IntTypeBounds for IntTy { + type Output = i128; + fn min_max(self) -> Option<(Self::Output, Self::Output)> { + Some(match self { + IntTy::I8 => (i8::MIN.into(), i8::MAX.into()), + IntTy::I16 => (i16::MIN.into(), i16::MAX.into()), + IntTy::I32 => (i32::MIN.into(), i32::MAX.into()), + IntTy::I64 => (i64::MIN.into(), i64::MAX.into()), + IntTy::I128 => (i128::MIN, i128::MAX), + IntTy::Isize => (isize::MIN.try_into().ok()?, isize::MAX.try_into().ok()?), + }) + } + fn bits(self) -> Self::Output { + match self { + IntTy::I8 => 8, + IntTy::I16 => 16, + IntTy::I32 => 32, + IntTy::I64 => 64, + IntTy::I128 => 128, + IntTy::Isize => isize::BITS.into(), + } + } +} + impl<'tcx> PartialEq for Constant<'tcx> { fn eq(&self, other: &Self) -> bool { match (self, other) { @@ -435,8 +492,15 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> { match *o { Int(value) => { let ty::Int(ity) = *ty.kind() else { return None }; + let (min, _) = ity.min_max()?; // sign extend let value = sext(self.lcx.tcx, value, ity); + + // Applying unary - to the most negative value of any signed integer type panics. + if value == min { + return None; + } + let value = value.checked_neg()?; // clear unused bits Some(Int(unsext(self.lcx.tcx, value, ity))) @@ -572,17 +636,33 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> { match (l, r) { (Constant::Int(l), Some(Constant::Int(r))) => match *self.typeck_results.expr_ty_opt(left)?.kind() { ty::Int(ity) => { + let (ty_min_value, _) = ity.min_max()?; + let bits = ity.bits(); let l = sext(self.lcx.tcx, l, ity); let r = sext(self.lcx.tcx, r, ity); + + // Using / or %, where the left-hand argument is the smallest integer of a signed integer type and + // the right-hand argument is -1 always panics, even with overflow-checks disabled + if let BinOpKind::Div | BinOpKind::Rem = op.node + && l == ty_min_value + && r == -1 + { + return None; + } + let zext = |n: i128| Constant::Int(unsext(self.lcx.tcx, n, ity)); match op.node { - BinOpKind::Add => l.checked_add(r).map(zext), - BinOpKind::Sub => l.checked_sub(r).map(zext), - BinOpKind::Mul => l.checked_mul(r).map(zext), + // When +, * or binary - create a value greater than the maximum value, or less than + // the minimum value that can be stored, it panics. + BinOpKind::Add => l.checked_add(r).and_then(|n| ity.ensure_fits(n)).map(zext), + BinOpKind::Sub => l.checked_sub(r).and_then(|n| ity.ensure_fits(n)).map(zext), + BinOpKind::Mul => l.checked_mul(r).and_then(|n| ity.ensure_fits(n)).map(zext), BinOpKind::Div if r != 0 => l.checked_div(r).map(zext), BinOpKind::Rem if r != 0 => l.checked_rem(r).map(zext), - BinOpKind::Shr => l.checked_shr(r.try_into().ok()?).map(zext), - BinOpKind::Shl => l.checked_shl(r.try_into().ok()?).map(zext), + // Using << or >> where the right-hand argument is greater than or equal to the number of bits + // in the type of the left-hand argument, or is negative panics. + BinOpKind::Shr if r < bits && !r.is_negative() => l.checked_shr(r.try_into().ok()?).map(zext), + BinOpKind::Shl if r < bits && !r.is_negative() => l.checked_shl(r.try_into().ok()?).map(zext), BinOpKind::BitXor => Some(zext(l ^ r)), BinOpKind::BitOr => Some(zext(l | r)), BinOpKind::BitAnd => Some(zext(l & r)), @@ -595,24 +675,28 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> { _ => None, } }, - ty::Uint(_) => match op.node { - BinOpKind::Add => l.checked_add(r).map(Constant::Int), - BinOpKind::Sub => l.checked_sub(r).map(Constant::Int), - BinOpKind::Mul => l.checked_mul(r).map(Constant::Int), - BinOpKind::Div => l.checked_div(r).map(Constant::Int), - BinOpKind::Rem => l.checked_rem(r).map(Constant::Int), - BinOpKind::Shr => l.checked_shr(r.try_into().ok()?).map(Constant::Int), - BinOpKind::Shl => l.checked_shl(r.try_into().ok()?).map(Constant::Int), - BinOpKind::BitXor => Some(Constant::Int(l ^ r)), - BinOpKind::BitOr => Some(Constant::Int(l | r)), - BinOpKind::BitAnd => Some(Constant::Int(l & r)), - BinOpKind::Eq => Some(Constant::Bool(l == r)), - BinOpKind::Ne => Some(Constant::Bool(l != r)), - BinOpKind::Lt => Some(Constant::Bool(l < r)), - BinOpKind::Le => Some(Constant::Bool(l <= r)), - BinOpKind::Ge => Some(Constant::Bool(l >= r)), - BinOpKind::Gt => Some(Constant::Bool(l > r)), - _ => None, + ty::Uint(ity) => { + let bits = ity.bits(); + + match op.node { + BinOpKind::Add => l.checked_add(r).and_then(|n| ity.ensure_fits(n)).map(Constant::Int), + BinOpKind::Sub => l.checked_sub(r).and_then(|n| ity.ensure_fits(n)).map(Constant::Int), + BinOpKind::Mul => l.checked_mul(r).and_then(|n| ity.ensure_fits(n)).map(Constant::Int), + BinOpKind::Div => l.checked_div(r).map(Constant::Int), + BinOpKind::Rem => l.checked_rem(r).map(Constant::Int), + BinOpKind::Shr if r < bits => l.checked_shr(r.try_into().ok()?).map(Constant::Int), + BinOpKind::Shl if r < bits => l.checked_shl(r.try_into().ok()?).map(Constant::Int), + BinOpKind::BitXor => Some(Constant::Int(l ^ r)), + BinOpKind::BitOr => Some(Constant::Int(l | r)), + BinOpKind::BitAnd => Some(Constant::Int(l & r)), + BinOpKind::Eq => Some(Constant::Bool(l == r)), + BinOpKind::Ne => Some(Constant::Bool(l != r)), + BinOpKind::Lt => Some(Constant::Bool(l < r)), + BinOpKind::Le => Some(Constant::Bool(l <= r)), + BinOpKind::Ge => Some(Constant::Bool(l >= r)), + BinOpKind::Gt => Some(Constant::Bool(l > r)), + _ => None, + } }, _ => None, }, diff --git a/clippy_utils/src/eager_or_lazy.rs b/clippy_utils/src/eager_or_lazy.rs index 0bcefba75a7b..9a48e7727748 100644 --- a/clippy_utils/src/eager_or_lazy.rs +++ b/clippy_utils/src/eager_or_lazy.rs @@ -9,12 +9,13 @@ //! - or-fun-call //! - option-if-let-else +use crate::consts::{constant, FullInt}; use crate::ty::{all_predicates_of, is_copy}; use crate::visitors::is_const_evaluatable; use rustc_hir::def::{DefKind, Res}; use rustc_hir::def_id::DefId; use rustc_hir::intravisit::{walk_expr, Visitor}; -use rustc_hir::{Block, Expr, ExprKind, QPath, UnOp}; +use rustc_hir::{BinOpKind, Block, Expr, ExprKind, QPath, UnOp}; use rustc_lint::LateContext; use rustc_middle::ty; use rustc_middle::ty::adjustment::Adjust; @@ -193,6 +194,12 @@ fn expr_eagerness<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> EagernessS self.eagerness = Lazy; } }, + + // `-i32::MIN` panics with overflow checks, but `constant` lets us rule out some simple cases + ExprKind::Unary(UnOp::Neg, _) if constant(self.cx, self.cx.typeck_results(), e).is_none() => { + self.eagerness |= NoChange; + }, + // Custom `Deref` impl might have side effects ExprKind::Unary(UnOp::Deref, e) if self.cx.typeck_results().expr_ty(e).builtin_deref(true).is_none() => @@ -207,6 +214,37 @@ fn expr_eagerness<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> EagernessS self.cx.typeck_results().expr_ty(e).kind(), ty::Bool | ty::Int(_) | ty::Uint(_), ) => {}, + + // `>>` and `<<` panic when the right-hand side is greater than or equal to the number of bits in the + // type of the left-hand side, or is negative. Doesn't need `constant` on the whole expression + // because only the right side matters. + ExprKind::Binary(op, left, right) + if matches!(op.node, BinOpKind::Shl | BinOpKind::Shr) + && let left_ty = self.cx.typeck_results().expr_ty(left) + && let left_bits = left_ty.int_size_and_signed(self.cx.tcx).0.bits() + && constant(self.cx, self.cx.typeck_results(), right) + .and_then(|c| c.int_value(self.cx, left_ty)) + .map_or(true, |c| match c { + FullInt::S(i) => i >= i128::from(left_bits) || i.is_negative(), + FullInt::U(i) => i >= u128::from(left_bits), + }) => + { + self.eagerness |= NoChange; + }, + + // Arithmetic operations panic on under-/overflow with overflow checks, so don't suggest changing it: + // https://doc.rust-lang.org/stable/reference/expressions/operator-expr.html#overflow + // Using `constant` lets us allow some simple cases where we know for sure it can't overflow + ExprKind::Binary(op, ..) + if matches!( + op.node, + BinOpKind::Add | BinOpKind::Mul | BinOpKind::Sub | BinOpKind::Div | BinOpKind::Rem + ) && !self.cx.typeck_results().expr_ty(e).is_floating_point() + && constant(self.cx, self.cx.typeck_results(), e).is_none() => + { + self.eagerness |= NoChange; + }, + ExprKind::Binary(_, lhs, rhs) if self.cx.typeck_results().expr_ty(lhs).is_primitive() && self.cx.typeck_results().expr_ty(rhs).is_primitive() => {}, diff --git a/tests/ui/unnecessary_lazy_eval.fixed b/tests/ui/unnecessary_lazy_eval.fixed index 4778eaefdbdb..da5da9ef85f0 100644 --- a/tests/ui/unnecessary_lazy_eval.fixed +++ b/tests/ui/unnecessary_lazy_eval.fixed @@ -6,6 +6,8 @@ #![allow(clippy::needless_borrow)] #![allow(clippy::unnecessary_literal_unwrap)] #![allow(clippy::unit_arg)] +#![allow(arithmetic_overflow)] +#![allow(unconditional_panic)] use std::ops::Deref; @@ -183,6 +185,9 @@ fn main() { // neither bind_instead_of_map nor unnecessary_lazy_eval applies here let _: Result = res.and_then(|x| Err(x)); let _: Result = res.or_else(|err| Ok(err)); + + issue9422(3); + panicky_arithmetic_ops(3); } #[allow(unused)] @@ -190,3 +195,44 @@ fn issue9485() { // should not lint, is in proc macro with_span!(span Some(42).unwrap_or_else(|| 2);); } + +fn issue9422(x: usize) -> Option { + (x >= 5).then(|| x - 5) + // (x >= 5).then_some(x - 5) // clippy suggestion panics +} + +// https://doc.rust-lang.org/stable/reference/expressions/operator-expr.html#overflow +fn panicky_arithmetic_ops(x: usize) { + let _x = false.then(|| i32::MAX + 1); + let _x = false.then(|| i32::MAX * 2); + let _x = false.then_some(i32::MAX - 1); + //~^ ERROR: unnecessary closure used with `bool::then` + let _x = false.then(|| i32::MIN - 1); + #[allow(clippy::identity_op)] + let _x = false.then_some((1 + 2 * 3 - 2 / 3 + 9) << 2); + //~^ ERROR: unnecessary closure used with `bool::then` + let _x = false.then_some(255u8 << 7); + //~^ ERROR: unnecessary closure used with `bool::then` + let _x = false.then(|| 255u8 << 8); + let _x = false.then(|| 255u8 >> 8); + let _x = false.then(|| 255u8 >> x); + let _x = false.then(|| i32::MIN / -1); + let _x = false.then_some(i32::MAX + -1); + //~^ ERROR: unnecessary closure used with `bool::then` + let _x = false.then_some(-i32::MAX); + //~^ ERROR: unnecessary closure used with `bool::then` + let _x = false.then(|| -i32::MIN); + let _x = false.then(|| 255 >> -7); + let _x = false.then(|| 255 << -1); + let _x = false.then(|| 1 / 0); + let _x = false.then(|| x << -1); + let _x = false.then_some(x << 2); + //~^ ERROR: unnecessary closure used with `bool::then` + + // const eval doesn't read variables, but floating point math never panics, so we can still emit a + // warning + let f1 = 1.0; + let f2 = 2.0; + let _x = false.then_some(f1 + f2); + //~^ ERROR: unnecessary closure used with `bool::then` +} diff --git a/tests/ui/unnecessary_lazy_eval.rs b/tests/ui/unnecessary_lazy_eval.rs index d4b7fd31b1b0..18b7eb4760fb 100644 --- a/tests/ui/unnecessary_lazy_eval.rs +++ b/tests/ui/unnecessary_lazy_eval.rs @@ -6,6 +6,8 @@ #![allow(clippy::needless_borrow)] #![allow(clippy::unnecessary_literal_unwrap)] #![allow(clippy::unit_arg)] +#![allow(arithmetic_overflow)] +#![allow(unconditional_panic)] use std::ops::Deref; @@ -183,6 +185,9 @@ fn main() { // neither bind_instead_of_map nor unnecessary_lazy_eval applies here let _: Result = res.and_then(|x| Err(x)); let _: Result = res.or_else(|err| Ok(err)); + + issue9422(3); + panicky_arithmetic_ops(3); } #[allow(unused)] @@ -190,3 +195,44 @@ fn issue9485() { // should not lint, is in proc macro with_span!(span Some(42).unwrap_or_else(|| 2);); } + +fn issue9422(x: usize) -> Option { + (x >= 5).then(|| x - 5) + // (x >= 5).then_some(x - 5) // clippy suggestion panics +} + +// https://doc.rust-lang.org/stable/reference/expressions/operator-expr.html#overflow +fn panicky_arithmetic_ops(x: usize) { + let _x = false.then(|| i32::MAX + 1); + let _x = false.then(|| i32::MAX * 2); + let _x = false.then(|| i32::MAX - 1); + //~^ ERROR: unnecessary closure used with `bool::then` + let _x = false.then(|| i32::MIN - 1); + #[allow(clippy::identity_op)] + let _x = false.then(|| (1 + 2 * 3 - 2 / 3 + 9) << 2); + //~^ ERROR: unnecessary closure used with `bool::then` + let _x = false.then(|| 255u8 << 7); + //~^ ERROR: unnecessary closure used with `bool::then` + let _x = false.then(|| 255u8 << 8); + let _x = false.then(|| 255u8 >> 8); + let _x = false.then(|| 255u8 >> x); + let _x = false.then(|| i32::MIN / -1); + let _x = false.then(|| i32::MAX + -1); + //~^ ERROR: unnecessary closure used with `bool::then` + let _x = false.then(|| -i32::MAX); + //~^ ERROR: unnecessary closure used with `bool::then` + let _x = false.then(|| -i32::MIN); + let _x = false.then(|| 255 >> -7); + let _x = false.then(|| 255 << -1); + let _x = false.then(|| 1 / 0); + let _x = false.then(|| x << -1); + let _x = false.then(|| x << 2); + //~^ ERROR: unnecessary closure used with `bool::then` + + // const eval doesn't read variables, but floating point math never panics, so we can still emit a + // warning + let f1 = 1.0; + let f2 = 2.0; + let _x = false.then(|| f1 + f2); + //~^ ERROR: unnecessary closure used with `bool::then` +} diff --git a/tests/ui/unnecessary_lazy_eval.stderr b/tests/ui/unnecessary_lazy_eval.stderr index 1b0db4759bba..55cbed7a4150 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:69:13 + --> $DIR/unnecessary_lazy_eval.rs:71:13 | LL | let _ = opt.unwrap_or_else(|| 2); | ^^^^-------------------- @@ -10,7 +10,7 @@ LL | let _ = opt.unwrap_or_else(|| 2); = help: to override `-D warnings` add `#[allow(clippy::unnecessary_lazy_evaluations)]` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:70:13 + --> $DIR/unnecessary_lazy_eval.rs:72:13 | LL | let _ = opt.unwrap_or_else(|| astronomers_pi); | ^^^^--------------------------------- @@ -18,7 +18,7 @@ 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:71:13 + --> $DIR/unnecessary_lazy_eval.rs:73:13 | LL | let _ = opt.unwrap_or_else(|| ext_str.some_field); | ^^^^------------------------------------- @@ -26,7 +26,7 @@ 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:73:13 + --> $DIR/unnecessary_lazy_eval.rs:75:13 | LL | let _ = opt.and_then(|_| ext_opt); | ^^^^--------------------- @@ -34,7 +34,7 @@ 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:74:13 + --> $DIR/unnecessary_lazy_eval.rs:76:13 | LL | let _ = opt.or_else(|| ext_opt); | ^^^^------------------- @@ -42,7 +42,7 @@ 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:75:13 + --> $DIR/unnecessary_lazy_eval.rs:77:13 | LL | let _ = opt.or_else(|| None); | ^^^^---------------- @@ -50,7 +50,7 @@ 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:76:13 + --> $DIR/unnecessary_lazy_eval.rs:78:13 | LL | let _ = opt.get_or_insert_with(|| 2); | ^^^^------------------------ @@ -58,7 +58,7 @@ 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:77:13 + --> $DIR/unnecessary_lazy_eval.rs:79:13 | LL | let _ = opt.ok_or_else(|| 2); | ^^^^---------------- @@ -66,7 +66,7 @@ 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:78:13 + --> $DIR/unnecessary_lazy_eval.rs:80:13 | LL | let _ = nested_tuple_opt.unwrap_or_else(|| Some((1, 2))); | ^^^^^^^^^^^^^^^^^------------------------------- @@ -74,7 +74,7 @@ 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:79:13 + --> $DIR/unnecessary_lazy_eval.rs:81:13 | LL | let _ = cond.then(|| astronomers_pi); | ^^^^^----------------------- @@ -82,7 +82,7 @@ LL | let _ = cond.then(|| astronomers_pi); | help: use `then_some(..)` instead: `then_some(astronomers_pi)` error: unnecessary closure used with `bool::then` - --> $DIR/unnecessary_lazy_eval.rs:80:13 + --> $DIR/unnecessary_lazy_eval.rs:82:13 | LL | let _ = true.then(|| -> _ {}); | ^^^^^---------------- @@ -90,7 +90,7 @@ LL | let _ = true.then(|| -> _ {}); | help: use `then_some(..)` instead: `then_some({})` error: unnecessary closure used with `bool::then` - --> $DIR/unnecessary_lazy_eval.rs:81:13 + --> $DIR/unnecessary_lazy_eval.rs:83:13 | LL | let _ = true.then(|| {}); | ^^^^^----------- @@ -98,7 +98,7 @@ LL | let _ = true.then(|| {}); | help: use `then_some(..)` instead: `then_some({})` error: unnecessary closure used to substitute value for `Option::None` - --> $DIR/unnecessary_lazy_eval.rs:85:13 + --> $DIR/unnecessary_lazy_eval.rs:87:13 | LL | let _ = Some(1).unwrap_or_else(|| *r); | ^^^^^^^^--------------------- @@ -106,7 +106,7 @@ 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:87:13 + --> $DIR/unnecessary_lazy_eval.rs:89:13 | LL | let _ = Some(1).unwrap_or_else(|| *b); | ^^^^^^^^--------------------- @@ -114,7 +114,7 @@ LL | let _ = Some(1).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:89:13 + --> $DIR/unnecessary_lazy_eval.rs:91:13 | LL | let _ = Some(1).as_ref().unwrap_or_else(|| &r); | ^^^^^^^^^^^^^^^^^--------------------- @@ -122,7 +122,7 @@ 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:90:13 + --> $DIR/unnecessary_lazy_eval.rs:92:13 | LL | let _ = Some(1).as_ref().unwrap_or_else(|| &b); | ^^^^^^^^^^^^^^^^^--------------------- @@ -130,7 +130,7 @@ 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:93:13 + --> $DIR/unnecessary_lazy_eval.rs:95:13 | LL | let _ = Some(10).unwrap_or_else(|| 2); | ^^^^^^^^^-------------------- @@ -138,7 +138,7 @@ 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:94:13 + --> $DIR/unnecessary_lazy_eval.rs:96:13 | LL | let _ = Some(10).and_then(|_| ext_opt); | ^^^^^^^^^--------------------- @@ -146,7 +146,7 @@ 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:95:28 + --> $DIR/unnecessary_lazy_eval.rs:97:28 | LL | let _: Option = None.or_else(|| ext_opt); | ^^^^^------------------- @@ -154,7 +154,7 @@ 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:96:13 + --> $DIR/unnecessary_lazy_eval.rs:98:13 | LL | let _ = None.get_or_insert_with(|| 2); | ^^^^^------------------------ @@ -162,7 +162,7 @@ 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:97:35 + --> $DIR/unnecessary_lazy_eval.rs:99:35 | LL | let _: Result = None.ok_or_else(|| 2); | ^^^^^---------------- @@ -170,7 +170,7 @@ 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:98:28 + --> $DIR/unnecessary_lazy_eval.rs:100:28 | LL | let _: Option = None.or_else(|| None); | ^^^^^---------------- @@ -178,7 +178,7 @@ 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:101:13 + --> $DIR/unnecessary_lazy_eval.rs:103:13 | LL | let _ = deep.0.unwrap_or_else(|| 2); | ^^^^^^^-------------------- @@ -186,7 +186,7 @@ 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:102:13 + --> $DIR/unnecessary_lazy_eval.rs:104:13 | LL | let _ = deep.0.and_then(|_| ext_opt); | ^^^^^^^--------------------- @@ -194,7 +194,7 @@ 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:103:13 + --> $DIR/unnecessary_lazy_eval.rs:105:13 | LL | let _ = deep.0.or_else(|| None); | ^^^^^^^---------------- @@ -202,7 +202,7 @@ 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:104:13 + --> $DIR/unnecessary_lazy_eval.rs:106:13 | LL | let _ = deep.0.get_or_insert_with(|| 2); | ^^^^^^^------------------------ @@ -210,7 +210,7 @@ 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:105:13 + --> $DIR/unnecessary_lazy_eval.rs:107:13 | LL | let _ = deep.0.ok_or_else(|| 2); | ^^^^^^^---------------- @@ -218,7 +218,7 @@ 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:135:28 + --> $DIR/unnecessary_lazy_eval.rs:137:28 | LL | let _: Option = None.or_else(|| Some(3)); | ^^^^^------------------- @@ -226,7 +226,7 @@ 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:136:13 + --> $DIR/unnecessary_lazy_eval.rs:138:13 | LL | let _ = deep.0.or_else(|| Some(3)); | ^^^^^^^------------------- @@ -234,7 +234,7 @@ 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:137:13 + --> $DIR/unnecessary_lazy_eval.rs:139:13 | LL | let _ = opt.or_else(|| Some(3)); | ^^^^------------------- @@ -242,7 +242,7 @@ 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:143:13 + --> $DIR/unnecessary_lazy_eval.rs:145:13 | LL | let _ = res2.unwrap_or_else(|_| 2); | ^^^^^--------------------- @@ -250,7 +250,7 @@ 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:144:13 + --> $DIR/unnecessary_lazy_eval.rs:146:13 | LL | let _ = res2.unwrap_or_else(|_| astronomers_pi); | ^^^^^---------------------------------- @@ -258,7 +258,7 @@ 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:145:13 + --> $DIR/unnecessary_lazy_eval.rs:147:13 | LL | let _ = res2.unwrap_or_else(|_| ext_str.some_field); | ^^^^^-------------------------------------- @@ -266,7 +266,7 @@ 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:167:35 + --> $DIR/unnecessary_lazy_eval.rs:169:35 | LL | let _: Result = res.and_then(|_| Err(2)); | ^^^^-------------------- @@ -274,7 +274,7 @@ 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:168:35 + --> $DIR/unnecessary_lazy_eval.rs:170:35 | LL | let _: Result = res.and_then(|_| Err(astronomers_pi)); | ^^^^--------------------------------- @@ -282,7 +282,7 @@ 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:169:35 + --> $DIR/unnecessary_lazy_eval.rs:171:35 | LL | let _: Result = res.and_then(|_| Err(ext_str.some_field)); | ^^^^------------------------------------- @@ -290,7 +290,7 @@ 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:171:35 + --> $DIR/unnecessary_lazy_eval.rs:173:35 | LL | let _: Result = res.or_else(|_| Ok(2)); | ^^^^------------------ @@ -298,7 +298,7 @@ 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:172:35 + --> $DIR/unnecessary_lazy_eval.rs:174:35 | LL | let _: Result = res.or_else(|_| Ok(astronomers_pi)); | ^^^^------------------------------- @@ -306,7 +306,7 @@ 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:173:35 + --> $DIR/unnecessary_lazy_eval.rs:175:35 | LL | let _: Result = res.or_else(|_| Ok(ext_str.some_field)); | ^^^^----------------------------------- @@ -314,7 +314,7 @@ 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:174:35 + --> $DIR/unnecessary_lazy_eval.rs:176:35 | LL | let _: Result = res. | ___________________________________^ @@ -328,5 +328,61 @@ LL | | or_else(|_| Ok(ext_str.some_field)); | | | help: use `or(..)` instead: `or(Ok(ext_str.some_field))` -error: aborting due to 40 previous errors +error: unnecessary closure used with `bool::then` + --> $DIR/unnecessary_lazy_eval.rs:208:14 + | +LL | let _x = false.then(|| i32::MAX - 1); + | ^^^^^^--------------------- + | | + | help: use `then_some(..)` instead: `then_some(i32::MAX - 1)` + +error: unnecessary closure used with `bool::then` + --> $DIR/unnecessary_lazy_eval.rs:212:14 + | +LL | let _x = false.then(|| (1 + 2 * 3 - 2 / 3 + 9) << 2); + | ^^^^^^------------------------------------- + | | + | help: use `then_some(..)` instead: `then_some((1 + 2 * 3 - 2 / 3 + 9) << 2)` + +error: unnecessary closure used with `bool::then` + --> $DIR/unnecessary_lazy_eval.rs:214:14 + | +LL | let _x = false.then(|| 255u8 << 7); + | ^^^^^^------------------- + | | + | help: use `then_some(..)` instead: `then_some(255u8 << 7)` + +error: unnecessary closure used with `bool::then` + --> $DIR/unnecessary_lazy_eval.rs:220:14 + | +LL | let _x = false.then(|| i32::MAX + -1); + | ^^^^^^---------------------- + | | + | help: use `then_some(..)` instead: `then_some(i32::MAX + -1)` + +error: unnecessary closure used with `bool::then` + --> $DIR/unnecessary_lazy_eval.rs:222:14 + | +LL | let _x = false.then(|| -i32::MAX); + | ^^^^^^------------------ + | | + | help: use `then_some(..)` instead: `then_some(-i32::MAX)` + +error: unnecessary closure used with `bool::then` + --> $DIR/unnecessary_lazy_eval.rs:229:14 + | +LL | let _x = false.then(|| x << 2); + | ^^^^^^--------------- + | | + | help: use `then_some(..)` instead: `then_some(x << 2)` + +error: unnecessary closure used with `bool::then` + --> $DIR/unnecessary_lazy_eval.rs:236:14 + | +LL | let _x = false.then(|| f1 + f2); + | ^^^^^^---------------- + | | + | help: use `then_some(..)` instead: `then_some(f1 + f2)` + +error: aborting due to 47 previous errors