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https://github.com/rust-lang/rust-clippy
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Auto merge of #12056 - PartiallyTyped:12050, r=xFrednet
Fixes: #12050 - `identity_op` correctly suggests a deference for coerced references When `identity_op` identifies a `no_op`, provides a suggestion, it also checks the type of the type of the variable. If the variable is a reference that's been coerced into a value, e.g. ``` let x = &0i32; let _ = x + 0; ``` the suggestion will now use a derefence. This is done by identifying whether the variable is a reference to an integral value, and then whether it gets dereferenced. changelog: false positive: [`identity_op`]: corrected suggestion for reference coerced to value. fixes: #12050
This commit is contained in:
bors
commit
2eb13d3a7c
4 changed files with 426 additions and 124 deletions
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@ -18,6 +18,28 @@ pub(crate) fn check<'tcx>(
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right: &'tcx Expr<'_>,
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) {
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if !is_allowed(cx, op, left, right) {
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return;
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}
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// we need to know whether a ref is coerced to a value
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// if a ref is coerced, then the suggested lint must deref it
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// e.g. `let _: i32 = x+0` with `x: &i32` should be replaced with `let _: i32 = *x`.
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// we do this by checking the _kind_ of the type of the expression
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// if it's a ref, we then check whether it is erased, and that's it.
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let (peeled_left_span, left_is_coerced_to_value) = {
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let expr = peel_hir_expr_refs(left).0;
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let span = expr.span;
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let is_coerced = expr_is_erased_ref(cx, expr);
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(span, is_coerced)
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};
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let (peeled_right_span, right_is_coerced_to_value) = {
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let expr = peel_hir_expr_refs(right).0;
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let span = expr.span;
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let is_coerced = expr_is_erased_ref(cx, expr);
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(span, is_coerced)
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};
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match op {
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BinOpKind::Add | BinOpKind::BitOr | BinOpKind::BitXor => {
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check_op(
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@ -25,16 +47,18 @@ pub(crate) fn check<'tcx>(
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left,
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0,
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expr.span,
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peel_hir_expr_refs(right).0.span,
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peeled_right_span,
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needs_parenthesis(cx, expr, right),
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right_is_coerced_to_value,
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);
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check_op(
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cx,
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right,
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0,
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expr.span,
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peel_hir_expr_refs(left).0.span,
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peeled_left_span,
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Parens::Unneeded,
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left_is_coerced_to_value,
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);
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},
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BinOpKind::Shl | BinOpKind::Shr | BinOpKind::Sub => {
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@ -43,8 +67,9 @@ pub(crate) fn check<'tcx>(
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right,
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0,
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expr.span,
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peel_hir_expr_refs(left).0.span,
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peeled_left_span,
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Parens::Unneeded,
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left_is_coerced_to_value,
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);
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},
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BinOpKind::Mul => {
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@ -53,16 +78,18 @@ pub(crate) fn check<'tcx>(
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left,
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1,
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expr.span,
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peel_hir_expr_refs(right).0.span,
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peeled_right_span,
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needs_parenthesis(cx, expr, right),
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right_is_coerced_to_value,
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);
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check_op(
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cx,
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right,
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1,
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expr.span,
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peel_hir_expr_refs(left).0.span,
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peeled_left_span,
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Parens::Unneeded,
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left_is_coerced_to_value,
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);
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},
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BinOpKind::Div => check_op(
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@ -70,8 +97,9 @@ pub(crate) fn check<'tcx>(
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right,
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1,
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expr.span,
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peel_hir_expr_refs(left).0.span,
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peeled_left_span,
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Parens::Unneeded,
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left_is_coerced_to_value,
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),
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BinOpKind::BitAnd => {
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check_op(
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@ -79,22 +107,30 @@ pub(crate) fn check<'tcx>(
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left,
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-1,
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expr.span,
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peel_hir_expr_refs(right).0.span,
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peeled_right_span,
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needs_parenthesis(cx, expr, right),
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right_is_coerced_to_value,
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);
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check_op(
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cx,
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right,
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-1,
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expr.span,
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peel_hir_expr_refs(left).0.span,
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peeled_left_span,
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Parens::Unneeded,
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left_is_coerced_to_value,
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);
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},
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BinOpKind::Rem => check_remainder(cx, left, right, expr.span, left.span),
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_ => (),
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}
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}
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fn expr_is_erased_ref(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
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match cx.typeck_results().expr_ty(expr).kind() {
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ty::Ref(r, ..) => r.is_erased(),
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_ => false,
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}
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}
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#[derive(Copy, Clone)]
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@ -144,11 +180,11 @@ fn needs_parenthesis(cx: &LateContext<'_>, binary: &Expr<'_>, right: &Expr<'_>)
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}
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fn is_allowed(cx: &LateContext<'_>, cmp: BinOpKind, left: &Expr<'_>, right: &Expr<'_>) -> bool {
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// This lint applies to integers
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!cx.typeck_results().expr_ty(left).peel_refs().is_integral()
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|| !cx.typeck_results().expr_ty(right).peel_refs().is_integral()
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// This lint applies to integers and their references
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cx.typeck_results().expr_ty(left).peel_refs().is_integral()
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&& cx.typeck_results().expr_ty(right).peel_refs().is_integral()
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// `1 << 0` is a common pattern in bit manipulation code
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|| (cmp == BinOpKind::Shl
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&& !(cmp == BinOpKind::Shl
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&& constant_simple(cx, cx.typeck_results(), right) == Some(Constant::Int(0))
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&& constant_simple(cx, cx.typeck_results(), left) == Some(Constant::Int(1)))
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}
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@ -161,11 +197,11 @@ fn check_remainder(cx: &LateContext<'_>, left: &Expr<'_>, right: &Expr<'_>, span
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(Some(FullInt::U(lv)), Some(FullInt::U(rv))) => lv < rv,
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_ => return,
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} {
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span_ineffective_operation(cx, span, arg, Parens::Unneeded);
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span_ineffective_operation(cx, span, arg, Parens::Unneeded, false);
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}
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}
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fn check_op(cx: &LateContext<'_>, e: &Expr<'_>, m: i8, span: Span, arg: Span, parens: Parens) {
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fn check_op(cx: &LateContext<'_>, e: &Expr<'_>, m: i8, span: Span, arg: Span, parens: Parens, is_erased: bool) {
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if let Some(Constant::Int(v)) = constant_simple(cx, cx.typeck_results(), e).map(Constant::peel_refs) {
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let check = match *cx.typeck_results().expr_ty(e).peel_refs().kind() {
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ty::Int(ity) => unsext(cx.tcx, -1_i128, ity),
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@ -178,18 +214,28 @@ fn check_op(cx: &LateContext<'_>, e: &Expr<'_>, m: i8, span: Span, arg: Span, pa
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1 => v == 1,
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_ => unreachable!(),
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} {
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span_ineffective_operation(cx, span, arg, parens);
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span_ineffective_operation(cx, span, arg, parens, is_erased);
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}
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}
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}
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fn span_ineffective_operation(cx: &LateContext<'_>, span: Span, arg: Span, parens: Parens) {
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fn span_ineffective_operation(
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cx: &LateContext<'_>,
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span: Span,
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arg: Span,
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parens: Parens,
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is_ref_coerced_to_val: bool,
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) {
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let mut applicability = Applicability::MachineApplicable;
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let expr_snippet = snippet_with_applicability(cx, arg, "..", &mut applicability);
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let expr_snippet = if is_ref_coerced_to_val {
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format!("*{expr_snippet}")
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} else {
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expr_snippet.into_owned()
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};
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let suggestion = match parens {
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Parens::Needed => format!("({expr_snippet})"),
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Parens::Unneeded => expr_snippet.into_owned(),
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Parens::Unneeded => expr_snippet,
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};
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span_lint_and_sugg(
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@ -6,7 +6,9 @@
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clippy::unnecessary_operation,
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clippy::op_ref,
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clippy::double_parens,
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clippy::uninlined_format_args
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clippy::uninlined_format_args,
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clippy::borrow_deref_ref,
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clippy::deref_addrof
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)]
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use std::fmt::Write as _;
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@ -40,32 +42,45 @@ fn main() {
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let x = 0;
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x;
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//~^ ERROR: this operation has no effect
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x;
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//~^ ERROR: this operation has no effect
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x + 1;
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x;
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//~^ ERROR: this operation has no effect
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1 + x;
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x - ZERO; //no error, as we skip lookups (for now)
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x;
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//~^ ERROR: this operation has no effect
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((ZERO)) | x; //no error, as we skip lookups (for now)
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x;
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//~^ ERROR: this operation has no effect
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x;
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//~^ ERROR: this operation has no effect
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x / ONE; //no error, as we skip lookups (for now)
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x / 2; //no false positive
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x & NEG_ONE; //no error, as we skip lookups (for now)
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x;
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//~^ ERROR: this operation has no effect
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let u: u8 = 0;
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u;
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//~^ ERROR: this operation has no effect
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1 << 0; // no error, this case is allowed, see issue 3430
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42;
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//~^ ERROR: this operation has no effect
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1;
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//~^ ERROR: this operation has no effect
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42;
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//~^ ERROR: this operation has no effect
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x;
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//~^ ERROR: this operation has no effect
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x;
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//~^ ERROR: this operation has no effect
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let mut a = A(String::new());
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let b = a << 0; // no error: non-integer
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@ -73,10 +88,15 @@ fn main() {
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1 * Meter; // no error: non-integer
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2;
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//~^ ERROR: this operation has no effect
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-2;
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//~^ ERROR: this operation has no effect
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2 + x;
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//~^ ERROR: this operation has no effect
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-2 + x;
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//~^ ERROR: this operation has no effect
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x + 1;
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//~^ ERROR: this operation has no effect
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(x + 1) % 3; // no error
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4 % 3; // no error
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4 % -3; // no error
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|
|
@ -85,38 +105,110 @@ fn main() {
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let a = 0;
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let b = true;
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(if b { 1 } else { 2 });
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//~^ ERROR: this operation has no effect
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(if b { 1 } else { 2 }) + if b { 3 } else { 4 };
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//~^ ERROR: this operation has no effect
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(match a { 0 => 10, _ => 20 });
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//~^ ERROR: this operation has no effect
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(match a { 0 => 10, _ => 20 }) + match a { 0 => 30, _ => 40 };
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//~^ ERROR: this operation has no effect
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(if b { 1 } else { 2 }) + match a { 0 => 30, _ => 40 };
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//~^ ERROR: this operation has no effect
|
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(match a { 0 => 10, _ => 20 }) + if b { 3 } else { 4 };
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//~^ ERROR: this operation has no effect
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(if b { 1 } else { 2 });
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//~^ ERROR: this operation has no effect
|
||||
|
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({ a }) + 3;
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//~^ ERROR: this operation has no effect
|
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({ a } * 2);
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//~^ ERROR: this operation has no effect
|
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(loop { let mut c = 0; if c == 10 { break c; } c += 1; }) + { a * 2 };
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//~^ ERROR: this operation has no effect
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|
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fn f(_: i32) {
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todo!();
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}
|
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|
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f(a + { 8 * 5 });
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//~^ ERROR: this operation has no effect
|
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f(if b { 1 } else { 2 } + 3);
|
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//~^ ERROR: this operation has no effect
|
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|
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const _: i32 = { 2 * 4 } + 3;
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//~^ ERROR: this operation has no effect
|
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const _: i32 = { 1 + 2 * 3 } + 3;
|
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//~^ ERROR: this operation has no effect
|
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|
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a as usize;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _ = a as usize;
|
||||
//~^ ERROR: this operation has no effect
|
||||
({ a } as usize);
|
||||
//~^ ERROR: this operation has no effect
|
||||
|
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2 * { a };
|
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//~^ ERROR: this operation has no effect
|
||||
(({ a } + 4));
|
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//~^ ERROR: this operation has no effect
|
||||
1;
|
||||
//~^ ERROR: this operation has no effect
|
||||
|
||||
// Issue #9904
|
||||
let x = 0i32;
|
||||
let _: i32 = x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
}
|
||||
|
||||
pub fn decide(a: bool, b: bool) -> u32 {
|
||||
(if a { 1 } else { 2 }) + if b { 3 } else { 5 }
|
||||
}
|
||||
|
||||
/// The following tests are from / for issue #12050
|
||||
/// In short, the lint didn't work for coerced references,
|
||||
/// e.g. let x = &0; let y = x + 0;
|
||||
/// because the suggested fix was `let y = x;` but
|
||||
/// it should have been `let y = *x;`
|
||||
fn issue_12050() {
|
||||
{
|
||||
let x = &0i32;
|
||||
let _: i32 = *x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _: i32 = *x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
}
|
||||
{
|
||||
let x = &&0i32;
|
||||
let _: i32 = **x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let x = &&0i32;
|
||||
let _: i32 = **x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
}
|
||||
{
|
||||
// this is just silly
|
||||
let x = &&&0i32;
|
||||
let _: i32 = ***x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _: i32 = ***x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let x = 0i32;
|
||||
let _: i32 = *&x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _: i32 = **&&x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _: i32 = *&*&x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _: i32 = **&&*&x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
}
|
||||
{
|
||||
// this is getting ridiculous, but we should still see the same
|
||||
// error message so let's just keep going
|
||||
let x = &0i32;
|
||||
let _: i32 = ***&&*&x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _: i32 = ***&&*&x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
}
|
||||
}
|
||||
|
|
|
|||
|
|
@ -6,7 +6,9 @@
|
|||
clippy::unnecessary_operation,
|
||||
clippy::op_ref,
|
||||
clippy::double_parens,
|
||||
clippy::uninlined_format_args
|
||||
clippy::uninlined_format_args,
|
||||
clippy::borrow_deref_ref,
|
||||
clippy::deref_addrof
|
||||
)]
|
||||
|
||||
use std::fmt::Write as _;
|
||||
|
|
@ -40,32 +42,45 @@ fn main() {
|
|||
let x = 0;
|
||||
|
||||
x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
x + (1 - 1);
|
||||
//~^ ERROR: this operation has no effect
|
||||
x + 1;
|
||||
0 + x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
1 + x;
|
||||
x - ZERO; //no error, as we skip lookups (for now)
|
||||
x | (0);
|
||||
//~^ ERROR: this operation has no effect
|
||||
((ZERO)) | x; //no error, as we skip lookups (for now)
|
||||
|
||||
x * 1;
|
||||
//~^ ERROR: this operation has no effect
|
||||
1 * x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
x / ONE; //no error, as we skip lookups (for now)
|
||||
|
||||
x / 2; //no false positive
|
||||
|
||||
x & NEG_ONE; //no error, as we skip lookups (for now)
|
||||
-1 & x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
|
||||
let u: u8 = 0;
|
||||
u & 255;
|
||||
//~^ ERROR: this operation has no effect
|
||||
|
||||
1 << 0; // no error, this case is allowed, see issue 3430
|
||||
42 << 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
1 >> 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
42 >> 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
&x >> 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
x >> &0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
|
||||
let mut a = A(String::new());
|
||||
let b = a << 0; // no error: non-integer
|
||||
|
|
@ -73,10 +88,15 @@ fn main() {
|
|||
1 * Meter; // no error: non-integer
|
||||
|
||||
2 % 3;
|
||||
//~^ ERROR: this operation has no effect
|
||||
-2 % 3;
|
||||
//~^ ERROR: this operation has no effect
|
||||
2 % -3 + x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
-2 % -3 + x;
|
||||
//~^ ERROR: this operation has no effect
|
||||
x + 1 % 3;
|
||||
//~^ ERROR: this operation has no effect
|
||||
(x + 1) % 3; // no error
|
||||
4 % 3; // no error
|
||||
4 % -3; // no error
|
||||
|
|
@ -85,38 +105,110 @@ fn main() {
|
|||
let a = 0;
|
||||
let b = true;
|
||||
0 + if b { 1 } else { 2 };
|
||||
//~^ ERROR: this operation has no effect
|
||||
0 + if b { 1 } else { 2 } + if b { 3 } else { 4 };
|
||||
//~^ ERROR: this operation has no effect
|
||||
0 + match a { 0 => 10, _ => 20 };
|
||||
//~^ ERROR: this operation has no effect
|
||||
0 + match a { 0 => 10, _ => 20 } + match a { 0 => 30, _ => 40 };
|
||||
//~^ ERROR: this operation has no effect
|
||||
0 + if b { 1 } else { 2 } + match a { 0 => 30, _ => 40 };
|
||||
//~^ ERROR: this operation has no effect
|
||||
0 + match a { 0 => 10, _ => 20 } + if b { 3 } else { 4 };
|
||||
//~^ ERROR: this operation has no effect
|
||||
(if b { 1 } else { 2 }) + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
|
||||
0 + { a } + 3;
|
||||
//~^ ERROR: this operation has no effect
|
||||
0 + { a } * 2;
|
||||
//~^ ERROR: this operation has no effect
|
||||
0 + loop { let mut c = 0; if c == 10 { break c; } c += 1; } + { a * 2 };
|
||||
//~^ ERROR: this operation has no effect
|
||||
|
||||
fn f(_: i32) {
|
||||
todo!();
|
||||
}
|
||||
|
||||
f(1 * a + { 8 * 5 });
|
||||
//~^ ERROR: this operation has no effect
|
||||
f(0 + if b { 1 } else { 2 } + 3);
|
||||
//~^ ERROR: this operation has no effect
|
||||
|
||||
const _: i32 = { 2 * 4 } + 0 + 3;
|
||||
//~^ ERROR: this operation has no effect
|
||||
const _: i32 = 0 + { 1 + 2 * 3 } + 3;
|
||||
//~^ ERROR: this operation has no effect
|
||||
|
||||
0 + a as usize;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _ = 0 + a as usize;
|
||||
//~^ ERROR: this operation has no effect
|
||||
0 + { a } as usize;
|
||||
//~^ ERROR: this operation has no effect
|
||||
|
||||
2 * (0 + { a });
|
||||
//~^ ERROR: this operation has no effect
|
||||
1 * ({ a } + 4);
|
||||
//~^ ERROR: this operation has no effect
|
||||
1 * 1;
|
||||
//~^ ERROR: this operation has no effect
|
||||
|
||||
// Issue #9904
|
||||
let x = 0i32;
|
||||
let _: i32 = &x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
}
|
||||
|
||||
pub fn decide(a: bool, b: bool) -> u32 {
|
||||
0 + if a { 1 } else { 2 } + if b { 3 } else { 5 }
|
||||
}
|
||||
|
||||
/// The following tests are from / for issue #12050
|
||||
/// In short, the lint didn't work for coerced references,
|
||||
/// e.g. let x = &0; let y = x + 0;
|
||||
/// because the suggested fix was `let y = x;` but
|
||||
/// it should have been `let y = *x;`
|
||||
fn issue_12050() {
|
||||
{
|
||||
let x = &0i32;
|
||||
let _: i32 = *x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _: i32 = x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
}
|
||||
{
|
||||
let x = &&0i32;
|
||||
let _: i32 = **x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let x = &&0i32;
|
||||
let _: i32 = *x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
}
|
||||
{
|
||||
// this is just silly
|
||||
let x = &&&0i32;
|
||||
let _: i32 = ***x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _: i32 = **x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let x = 0i32;
|
||||
let _: i32 = *&x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _: i32 = **&&x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _: i32 = *&*&x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _: i32 = **&&*&x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
}
|
||||
{
|
||||
// this is getting ridiculous, but we should still see the same
|
||||
// error message so let's just keep going
|
||||
let x = &0i32;
|
||||
let _: i32 = **&&*&x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
let _: i32 = **&&*&x + 0;
|
||||
//~^ ERROR: this operation has no effect
|
||||
}
|
||||
}
|
||||
|
|
|
|||
|
|
@ -1,5 +1,5 @@
|
|||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:42:5
|
||||
--> $DIR/identity_op.rs:44:5
|
||||
|
|
||||
LL | x + 0;
|
||||
| ^^^^^ help: consider reducing it to: `x`
|
||||
|
|
@ -8,238 +8,310 @@ LL | x + 0;
|
|||
= help: to override `-D warnings` add `#[allow(clippy::identity_op)]`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:43:5
|
||||
--> $DIR/identity_op.rs:46:5
|
||||
|
|
||||
LL | x + (1 - 1);
|
||||
| ^^^^^^^^^^^ help: consider reducing it to: `x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:45:5
|
||||
--> $DIR/identity_op.rs:49:5
|
||||
|
|
||||
LL | 0 + x;
|
||||
| ^^^^^ help: consider reducing it to: `x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:48:5
|
||||
--> $DIR/identity_op.rs:53:5
|
||||
|
|
||||
LL | x | (0);
|
||||
| ^^^^^^^ help: consider reducing it to: `x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:51:5
|
||||
--> $DIR/identity_op.rs:57:5
|
||||
|
|
||||
LL | x * 1;
|
||||
| ^^^^^ help: consider reducing it to: `x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:52:5
|
||||
--> $DIR/identity_op.rs:59:5
|
||||
|
|
||||
LL | 1 * x;
|
||||
| ^^^^^ help: consider reducing it to: `x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:58:5
|
||||
--> $DIR/identity_op.rs:66:5
|
||||
|
|
||||
LL | -1 & x;
|
||||
| ^^^^^^ help: consider reducing it to: `x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:61:5
|
||||
--> $DIR/identity_op.rs:70:5
|
||||
|
|
||||
LL | u & 255;
|
||||
| ^^^^^^^ help: consider reducing it to: `u`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:64:5
|
||||
--> $DIR/identity_op.rs:74:5
|
||||
|
|
||||
LL | 42 << 0;
|
||||
| ^^^^^^^ help: consider reducing it to: `42`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:65:5
|
||||
--> $DIR/identity_op.rs:76:5
|
||||
|
|
||||
LL | 1 >> 0;
|
||||
| ^^^^^^ help: consider reducing it to: `1`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:66:5
|
||||
--> $DIR/identity_op.rs:78:5
|
||||
|
|
||||
LL | 42 >> 0;
|
||||
| ^^^^^^^ help: consider reducing it to: `42`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:67:5
|
||||
--> $DIR/identity_op.rs:80:5
|
||||
|
|
||||
LL | &x >> 0;
|
||||
| ^^^^^^^ help: consider reducing it to: `x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:68:5
|
||||
--> $DIR/identity_op.rs:82:5
|
||||
|
|
||||
LL | x >> &0;
|
||||
| ^^^^^^^ help: consider reducing it to: `x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:75:5
|
||||
--> $DIR/identity_op.rs:90:5
|
||||
|
|
||||
LL | 2 % 3;
|
||||
| ^^^^^ help: consider reducing it to: `2`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:76:5
|
||||
--> $DIR/identity_op.rs:92:5
|
||||
|
|
||||
LL | -2 % 3;
|
||||
| ^^^^^^ help: consider reducing it to: `-2`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:77:5
|
||||
--> $DIR/identity_op.rs:94:5
|
||||
|
|
||||
LL | 2 % -3 + x;
|
||||
| ^^^^^^ help: consider reducing it to: `2`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:78:5
|
||||
--> $DIR/identity_op.rs:96:5
|
||||
|
|
||||
LL | -2 % -3 + x;
|
||||
| ^^^^^^^ help: consider reducing it to: `-2`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:79:9
|
||||
--> $DIR/identity_op.rs:98:9
|
||||
|
|
||||
LL | x + 1 % 3;
|
||||
| ^^^^^ help: consider reducing it to: `1`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:87:5
|
||||
--> $DIR/identity_op.rs:107:5
|
||||
|
|
||||
LL | 0 + if b { 1 } else { 2 };
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider reducing it to: `(if b { 1 } else { 2 })`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:88:5
|
||||
--> $DIR/identity_op.rs:109:5
|
||||
|
|
||||
LL | 0 + if b { 1 } else { 2 } + if b { 3 } else { 4 };
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider reducing it to: `(if b { 1 } else { 2 })`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:89:5
|
||||
--> $DIR/identity_op.rs:111:5
|
||||
|
|
||||
LL | 0 + match a { 0 => 10, _ => 20 };
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider reducing it to: `(match a { 0 => 10, _ => 20 })`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:90:5
|
||||
--> $DIR/identity_op.rs:113:5
|
||||
|
|
||||
LL | 0 + match a { 0 => 10, _ => 20 } + match a { 0 => 30, _ => 40 };
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider reducing it to: `(match a { 0 => 10, _ => 20 })`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:91:5
|
||||
--> $DIR/identity_op.rs:115:5
|
||||
|
|
||||
LL | 0 + if b { 1 } else { 2 } + match a { 0 => 30, _ => 40 };
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider reducing it to: `(if b { 1 } else { 2 })`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:92:5
|
||||
--> $DIR/identity_op.rs:117:5
|
||||
|
|
||||
LL | 0 + match a { 0 => 10, _ => 20 } + if b { 3 } else { 4 };
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider reducing it to: `(match a { 0 => 10, _ => 20 })`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:93:5
|
||||
--> $DIR/identity_op.rs:119:5
|
||||
|
|
||||
LL | (if b { 1 } else { 2 }) + 0;
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider reducing it to: `(if b { 1 } else { 2 })`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:95:5
|
||||
--> $DIR/identity_op.rs:122:5
|
||||
|
|
||||
LL | 0 + { a } + 3;
|
||||
| ^^^^^^^^^ help: consider reducing it to: `({ a })`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:96:5
|
||||
--> $DIR/identity_op.rs:124:5
|
||||
|
|
||||
LL | 0 + { a } * 2;
|
||||
| ^^^^^^^^^^^^^ help: consider reducing it to: `({ a } * 2)`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:97:5
|
||||
--> $DIR/identity_op.rs:126:5
|
||||
|
|
||||
LL | 0 + loop { let mut c = 0; if c == 10 { break c; } c += 1; } + { a * 2 };
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider reducing it to: `(loop { let mut c = 0; if c == 10 { break c; } c += 1; })`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:102:7
|
||||
--> $DIR/identity_op.rs:133:7
|
||||
|
|
||||
LL | f(1 * a + { 8 * 5 });
|
||||
| ^^^^^ help: consider reducing it to: `a`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:103:7
|
||||
--> $DIR/identity_op.rs:135:7
|
||||
|
|
||||
LL | f(0 + if b { 1 } else { 2 } + 3);
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider reducing it to: `if b { 1 } else { 2 }`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:104:20
|
||||
--> $DIR/identity_op.rs:138:20
|
||||
|
|
||||
LL | const _: i32 = { 2 * 4 } + 0 + 3;
|
||||
| ^^^^^^^^^^^^^ help: consider reducing it to: `{ 2 * 4 }`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:105:20
|
||||
--> $DIR/identity_op.rs:140:20
|
||||
|
|
||||
LL | const _: i32 = 0 + { 1 + 2 * 3 } + 3;
|
||||
| ^^^^^^^^^^^^^^^^^ help: consider reducing it to: `{ 1 + 2 * 3 }`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:107:5
|
||||
--> $DIR/identity_op.rs:143:5
|
||||
|
|
||||
LL | 0 + a as usize;
|
||||
| ^^^^^^^^^^^^^^ help: consider reducing it to: `a as usize`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:108:13
|
||||
--> $DIR/identity_op.rs:145:13
|
||||
|
|
||||
LL | let _ = 0 + a as usize;
|
||||
| ^^^^^^^^^^^^^^ help: consider reducing it to: `a as usize`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:109:5
|
||||
--> $DIR/identity_op.rs:147:5
|
||||
|
|
||||
LL | 0 + { a } as usize;
|
||||
| ^^^^^^^^^^^^^^^^^^ help: consider reducing it to: `({ a } as usize)`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:111:9
|
||||
--> $DIR/identity_op.rs:150:9
|
||||
|
|
||||
LL | 2 * (0 + { a });
|
||||
| ^^^^^^^^^^^ help: consider reducing it to: `{ a }`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:112:5
|
||||
--> $DIR/identity_op.rs:152:5
|
||||
|
|
||||
LL | 1 * ({ a } + 4);
|
||||
| ^^^^^^^^^^^^^^^ help: consider reducing it to: `(({ a } + 4))`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:113:5
|
||||
--> $DIR/identity_op.rs:154:5
|
||||
|
|
||||
LL | 1 * 1;
|
||||
| ^^^^^ help: consider reducing it to: `1`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:117:18
|
||||
--> $DIR/identity_op.rs:159:18
|
||||
|
|
||||
LL | let _: i32 = &x + 0;
|
||||
| ^^^^^^ help: consider reducing it to: `x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:121:5
|
||||
--> $DIR/identity_op.rs:164:5
|
||||
|
|
||||
LL | 0 + if a { 1 } else { 2 } + if b { 3 } else { 5 }
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider reducing it to: `(if a { 1 } else { 2 })`
|
||||
|
||||
error: aborting due to 40 previous errors
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:175:22
|
||||
|
|
||||
LL | let _: i32 = *x + 0;
|
||||
| ^^^^^^ help: consider reducing it to: `*x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:177:22
|
||||
|
|
||||
LL | let _: i32 = x + 0;
|
||||
| ^^^^^ help: consider reducing it to: `*x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:182:22
|
||||
|
|
||||
LL | let _: i32 = **x + 0;
|
||||
| ^^^^^^^ help: consider reducing it to: `**x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:185:22
|
||||
|
|
||||
LL | let _: i32 = *x + 0;
|
||||
| ^^^^^^ help: consider reducing it to: `**x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:191:22
|
||||
|
|
||||
LL | let _: i32 = ***x + 0;
|
||||
| ^^^^^^^^ help: consider reducing it to: `***x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:193:22
|
||||
|
|
||||
LL | let _: i32 = **x + 0;
|
||||
| ^^^^^^^ help: consider reducing it to: `***x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:196:22
|
||||
|
|
||||
LL | let _: i32 = *&x + 0;
|
||||
| ^^^^^^^ help: consider reducing it to: `*&x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:198:22
|
||||
|
|
||||
LL | let _: i32 = **&&x + 0;
|
||||
| ^^^^^^^^^ help: consider reducing it to: `**&&x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:200:22
|
||||
|
|
||||
LL | let _: i32 = *&*&x + 0;
|
||||
| ^^^^^^^^^ help: consider reducing it to: `*&*&x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:202:22
|
||||
|
|
||||
LL | let _: i32 = **&&*&x + 0;
|
||||
| ^^^^^^^^^^^ help: consider reducing it to: `**&&*&x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:209:22
|
||||
|
|
||||
LL | let _: i32 = **&&*&x + 0;
|
||||
| ^^^^^^^^^^^ help: consider reducing it to: `***&&*&x`
|
||||
|
||||
error: this operation has no effect
|
||||
--> $DIR/identity_op.rs:211:22
|
||||
|
|
||||
LL | let _: i32 = **&&*&x + 0;
|
||||
| ^^^^^^^^^^^ help: consider reducing it to: `***&&*&x`
|
||||
|
||||
error: aborting due to 52 previous errors
|
||||
|
||||
|
|
|
|||
Loading…
Reference in a new issue