/// let _ = a.exp() - 1.0;
/// ```
///
- /// is better expressed as
- ///
+ /// Use instead:
/// ```rust
/// let a = 3f32;
/// let _ = a.cbrt();
if let ast::LitKind::Float(sym, ast::LitFloatType::Unsuffixed) = lit.node;
then {
let op = format!(
- "{}{}{}",
- suggestion,
+ "{suggestion}{}{}",
// Check for float literals without numbers following the decimal
// separator such as `2.` and adds a trailing zero
if sym.as_str().ends_with('.') {
suggestion.maybe_par()
}
-fn check_log_base(cx: &LateContext<'_>, expr: &Expr<'_>, args: &[Expr<'_>]) {
- if let Some(method) = get_specialized_log_method(cx, &args[1]) {
+fn check_log_base(cx: &LateContext<'_>, expr: &Expr<'_>, receiver: &Expr<'_>, args: &[Expr<'_>]) {
+ if let Some(method) = get_specialized_log_method(cx, &args[0]) {
span_lint_and_sugg(
cx,
SUBOPTIMAL_FLOPS,
expr.span,
"logarithm for bases 2, 10 and e can be computed more accurately",
"consider using",
- format!("{}.{}()", Sugg::hir(cx, &args[0], ".."), method),
+ format!("{}.{method}()", Sugg::hir(cx, receiver, "..").maybe_par()),
Applicability::MachineApplicable,
);
}
// TODO: Lint expressions of the form `(x + y).ln()` where y > 1 and
// suggest usage of `(x + (y - 1)).ln_1p()` instead
-fn check_ln1p(cx: &LateContext<'_>, expr: &Expr<'_>, args: &[Expr<'_>]) {
+fn check_ln1p(cx: &LateContext<'_>, expr: &Expr<'_>, receiver: &Expr<'_>) {
if let ExprKind::Binary(
Spanned {
node: BinOpKind::Add, ..
},
lhs,
rhs,
- ) = &args[0].kind
+ ) = receiver.kind
{
let recv = match (
constant(cx, cx.typeck_results(), lhs),
// converted to an integer without loss of precision. For now we only check
// ranges [-16777215, 16777216) for type f32 as whole number floats outside
// this range are lossy and ambiguous.
-#[allow(clippy::cast_possible_truncation)]
+#[expect(clippy::cast_possible_truncation)]
fn get_integer_from_float_constant(value: &Constant) -> Option<i32> {
match value {
F32(num) if num.fract() == 0.0 => {
}
}
-fn check_powf(cx: &LateContext<'_>, expr: &Expr<'_>, args: &[Expr<'_>]) {
+fn check_powf(cx: &LateContext<'_>, expr: &Expr<'_>, receiver: &Expr<'_>, args: &[Expr<'_>]) {
// Check receiver
- if let Some((value, _)) = constant(cx, cx.typeck_results(), &args[0]) {
- let method = if F32(f32_consts::E) == value || F64(f64_consts::E) == value {
- "exp"
+ if let Some((value, _)) = constant(cx, cx.typeck_results(), receiver) {
+ if let Some(method) = if F32(f32_consts::E) == value || F64(f64_consts::E) == value {
+ Some("exp")
} else if F32(2.0) == value || F64(2.0) == value {
- "exp2"
+ Some("exp2")
} else {
- return;
- };
-
- span_lint_and_sugg(
- cx,
- SUBOPTIMAL_FLOPS,
- expr.span,
- "exponent for bases 2 and e can be computed more accurately",
- "consider using",
- format!("{}.{}()", prepare_receiver_sugg(cx, &args[1]), method),
- Applicability::MachineApplicable,
- );
+ None
+ } {
+ span_lint_and_sugg(
+ cx,
+ SUBOPTIMAL_FLOPS,
+ expr.span,
+ "exponent for bases 2 and e can be computed more accurately",
+ "consider using",
+ format!("{}.{method}()", prepare_receiver_sugg(cx, &args[0])),
+ Applicability::MachineApplicable,
+ );
+ }
}
// Check argument
- if let Some((value, _)) = constant(cx, cx.typeck_results(), &args[1]) {
+ if let Some((value, _)) = constant(cx, cx.typeck_results(), &args[0]) {
let (lint, help, suggestion) = if F32(1.0 / 2.0) == value || F64(1.0 / 2.0) == value {
(
SUBOPTIMAL_FLOPS,
"square-root of a number can be computed more efficiently and accurately",
- format!("{}.sqrt()", Sugg::hir(cx, &args[0], "..")),
+ format!("{}.sqrt()", Sugg::hir(cx, receiver, "..").maybe_par()),
)
} else if F32(1.0 / 3.0) == value || F64(1.0 / 3.0) == value {
(
IMPRECISE_FLOPS,
"cube-root of a number can be computed more accurately",
- format!("{}.cbrt()", Sugg::hir(cx, &args[0], "..")),
+ format!("{}.cbrt()", Sugg::hir(cx, receiver, "..").maybe_par()),
)
} else if let Some(exponent) = get_integer_from_float_constant(&value) {
(
"exponentiation with integer powers can be computed more efficiently",
format!(
"{}.powi({})",
- Sugg::hir(cx, &args[0], ".."),
+ Sugg::hir(cx, receiver, "..").maybe_par(),
numeric_literal::format(&exponent.to_string(), None, false)
),
)
}
}
-fn check_powi(cx: &LateContext<'_>, expr: &Expr<'_>, args: &[Expr<'_>]) {
- if let Some((value, _)) = constant(cx, cx.typeck_results(), &args[1]) {
+fn check_powi(cx: &LateContext<'_>, expr: &Expr<'_>, receiver: &Expr<'_>, args: &[Expr<'_>]) {
+ if let Some((value, _)) = constant(cx, cx.typeck_results(), &args[0]) {
if value == Int(2) {
if let Some(parent) = get_parent_expr(cx, expr) {
if let Some(grandparent) = get_parent_expr(cx, parent) {
- if let ExprKind::MethodCall(PathSegment { ident: method_name, .. }, _, args, _) = grandparent.kind {
- if method_name.as_str() == "sqrt" && detect_hypot(cx, args).is_some() {
+ if let ExprKind::MethodCall(PathSegment { ident: method_name, .. }, receiver, ..) = grandparent.kind
+ {
+ if method_name.as_str() == "sqrt" && detect_hypot(cx, receiver).is_some() {
return;
}
}
if let ExprKind::Binary(
Spanned {
- node: BinOpKind::Add, ..
+ node: op @ (BinOpKind::Add | BinOpKind::Sub),
+ ..
},
lhs,
rhs,
{
let other_addend = if lhs.hir_id == expr.hir_id { rhs } else { lhs };
+ // Negate expr if original code has subtraction and expr is on the right side
+ let maybe_neg_sugg = |expr, hir_id| {
+ let sugg = Sugg::hir(cx, expr, "..");
+ if matches!(op, BinOpKind::Sub) && hir_id == rhs.hir_id {
+ format!("-{}", sugg.maybe_par())
+ } else {
+ sugg.to_string()
+ }
+ };
+
span_lint_and_sugg(
cx,
SUBOPTIMAL_FLOPS,
"consider using",
format!(
"{}.mul_add({}, {})",
- Sugg::hir(cx, &args[0], ".."),
- Sugg::hir(cx, &args[0], ".."),
- Sugg::hir(cx, other_addend, ".."),
+ Sugg::hir(cx, receiver, "..").maybe_par(),
+ maybe_neg_sugg(receiver, expr.hir_id),
+ maybe_neg_sugg(other_addend, other_addend.hir_id),
),
Applicability::MachineApplicable,
);
}
}
-fn detect_hypot(cx: &LateContext<'_>, args: &[Expr<'_>]) -> Option<String> {
+fn detect_hypot(cx: &LateContext<'_>, receiver: &Expr<'_>) -> Option<String> {
if let ExprKind::Binary(
Spanned {
node: BinOpKind::Add, ..
},
add_lhs,
add_rhs,
- ) = args[0].kind
+ ) = receiver.kind
{
// check if expression of the form x * x + y * y
if_chain! {
if_chain! {
if let ExprKind::MethodCall(
PathSegment { ident: lmethod_name, .. },
- _lspan,
- [largs_0, largs_1, ..],
+ largs_0, [largs_1, ..],
_
) = &add_lhs.kind;
if let ExprKind::MethodCall(
PathSegment { ident: rmethod_name, .. },
- _rspan,
- [rargs_0, rargs_1, ..],
+ rargs_0, [rargs_1, ..],
_
) = &add_rhs.kind;
if lmethod_name.as_str() == "powi" && rmethod_name.as_str() == "powi";
None
}
-fn check_hypot(cx: &LateContext<'_>, expr: &Expr<'_>, args: &[Expr<'_>]) {
- if let Some(message) = detect_hypot(cx, args) {
+fn check_hypot(cx: &LateContext<'_>, expr: &Expr<'_>, receiver: &Expr<'_>) {
+ if let Some(message) = detect_hypot(cx, receiver) {
span_lint_and_sugg(
cx,
IMPRECISE_FLOPS,
if cx.typeck_results().expr_ty(lhs).is_floating_point();
if let Some((value, _)) = constant(cx, cx.typeck_results(), rhs);
if F32(1.0) == value || F64(1.0) == value;
- if let ExprKind::MethodCall(path, _, [self_arg, ..], _) = &lhs.kind;
+ if let ExprKind::MethodCall(path, self_arg, ..) = &lhs.kind;
if cx.typeck_results().expr_ty(self_arg).is_floating_point();
if path.ident.name.as_str() == "exp";
then {
"consider using",
format!(
"{}.exp_m1()",
- Sugg::hir(cx, self_arg, "..")
+ Sugg::hir(cx, self_arg, "..").maybe_par()
),
Applicability::MachineApplicable,
);
fn check_mul_add(cx: &LateContext<'_>, expr: &Expr<'_>) {
if let ExprKind::Binary(
Spanned {
- node: BinOpKind::Add, ..
+ node: op @ (BinOpKind::Add | BinOpKind::Sub),
+ ..
},
lhs,
rhs,
) = &expr.kind
{
if let Some(parent) = get_parent_expr(cx, expr) {
- if let ExprKind::MethodCall(PathSegment { ident: method_name, .. }, _, args, _) = parent.kind {
- if method_name.as_str() == "sqrt" && detect_hypot(cx, args).is_some() {
+ if let ExprKind::MethodCall(PathSegment { ident: method_name, .. }, receiver, ..) = parent.kind {
+ if method_name.as_str() == "sqrt" && detect_hypot(cx, receiver).is_some() {
return;
}
}
}
+ let maybe_neg_sugg = |expr| {
+ let sugg = Sugg::hir(cx, expr, "..");
+ if let BinOpKind::Sub = op {
+ format!("-{sugg}")
+ } else {
+ sugg.to_string()
+ }
+ };
+
let (recv, arg1, arg2) = if let Some((inner_lhs, inner_rhs)) = is_float_mul_expr(cx, lhs) {
- (inner_lhs, inner_rhs, rhs)
+ (
+ inner_lhs,
+ Sugg::hir(cx, inner_rhs, "..").to_string(),
+ maybe_neg_sugg(rhs),
+ )
} else if let Some((inner_lhs, inner_rhs)) = is_float_mul_expr(cx, rhs) {
- (inner_lhs, inner_rhs, lhs)
+ (
+ inner_lhs,
+ maybe_neg_sugg(inner_rhs),
+ Sugg::hir(cx, lhs, "..").to_string(),
+ )
} else {
return;
};
expr.span,
"multiply and add expressions can be calculated more efficiently and accurately",
"consider using",
- format!(
- "{}.mul_add({}, {})",
- prepare_receiver_sugg(cx, recv),
- Sugg::hir(cx, arg1, ".."),
- Sugg::hir(cx, arg2, ".."),
- ),
+ format!("{}.mul_add({arg1}, {arg2})", prepare_receiver_sugg(cx, recv)),
Applicability::MachineApplicable,
);
}
then {
let positive_abs_sugg = (
"manual implementation of `abs` method",
- format!("{}.abs()", Sugg::hir(cx, body, "..")),
+ format!("{}.abs()", Sugg::hir(cx, body, "..").maybe_par()),
);
let negative_abs_sugg = (
"manual implementation of negation of `abs` method",
- format!("-{}.abs()", Sugg::hir(cx, body, "..")),
+ format!("-{}.abs()", Sugg::hir(cx, body, "..").maybe_par()),
);
let sugg = if is_testing_positive(cx, cond, body) {
if if_expr_positive {
return method_name_a.as_str() == method_name_b.as_str() &&
args_a.len() == args_b.len() &&
(
- ["ln", "log2", "log10"].contains(&&*method_name_a.as_str()) ||
- method_name_a.as_str() == "log" && args_a.len() == 2 && eq_expr_value(cx, &args_a[1], &args_b[1])
+ ["ln", "log2", "log10"].contains(&method_name_a.as_str()) ||
+ method_name_a.as_str() == "log" && args_a.len() == 1 && eq_expr_value(cx, &args_a[0], &args_b[0])
);
}
}
rhs,
) = &expr.kind;
if are_same_base_logs(cx, lhs, rhs);
- if let ExprKind::MethodCall(_, _, [largs_self, ..], _) = &lhs.kind;
- if let ExprKind::MethodCall(_, _, [rargs_self, ..], _) = &rhs.kind;
+ if let ExprKind::MethodCall(_, largs_self, ..) = &lhs.kind;
+ if let ExprKind::MethodCall(_, rargs_self, ..) = &rhs.kind;
then {
span_lint_and_sugg(
cx,
expr.span,
"log base can be expressed more clearly",
"consider using",
- format!("{}.log({})", Sugg::hir(cx, largs_self, ".."), Sugg::hir(cx, rargs_self, ".."),),
+ format!("{}.log({})", Sugg::hir(cx, largs_self, "..").maybe_par(), Sugg::hir(cx, rargs_self, ".."),),
Applicability::MachineApplicable,
);
}
if (F32(f32_consts::PI) == rvalue || F64(f64_consts::PI) == rvalue) &&
(F32(180_f32) == lvalue || F64(180_f64) == lvalue)
{
- let mut proposal = format!("{}.to_degrees()", Sugg::hir(cx, mul_lhs, ".."));
+ let mut proposal = format!("{}.to_degrees()", Sugg::hir(cx, mul_lhs, "..").maybe_par());
if_chain! {
if let ExprKind::Lit(ref literal) = mul_lhs.kind;
if let ast::LitKind::Float(ref value, float_type) = literal.node;
(F32(180_f32) == rvalue || F64(180_f64) == rvalue) &&
(F32(f32_consts::PI) == lvalue || F64(f64_consts::PI) == lvalue)
{
- let mut proposal = format!("{}.to_radians()", Sugg::hir(cx, mul_lhs, ".."));
+ let mut proposal = format!("{}.to_radians()", Sugg::hir(cx, mul_lhs, "..").maybe_par());
if_chain! {
if let ExprKind::Lit(ref literal) = mul_lhs.kind;
if let ast::LitKind::Float(ref value, float_type) = literal.node;
return;
}
- if let ExprKind::MethodCall(path, _, args, _) = &expr.kind {
- let recv_ty = cx.typeck_results().expr_ty(&args[0]);
+ if let ExprKind::MethodCall(path, receiver, args, _) = &expr.kind {
+ let recv_ty = cx.typeck_results().expr_ty(receiver);
if recv_ty.is_floating_point() {
- match &*path.ident.name.as_str() {
- "ln" => check_ln1p(cx, expr, args),
- "log" => check_log_base(cx, expr, args),
- "powf" => check_powf(cx, expr, args),
- "powi" => check_powi(cx, expr, args),
- "sqrt" => check_hypot(cx, expr, args),
+ match path.ident.name.as_str() {
+ "ln" => check_ln1p(cx, expr, receiver),
+ "log" => check_log_base(cx, expr, receiver, args),
+ "powf" => check_powf(cx, expr, receiver, args),
+ "powi" => check_powi(cx, expr, receiver, args),
+ "sqrt" => check_hypot(cx, expr, receiver),
_ => {},
}
}
projects / rust.git / blobdiff