use clippy_utils::consts::{constant, Constant};
use clippy_utils::sugg::Sugg;
use clippy_utils::{
- expr_path_res, get_item_name, get_parent_expr, higher, in_constant, is_diag_trait_item, is_integer_const,
- iter_input_pats, last_path_segment, match_any_def_paths, paths, unsext, SpanlessEq,
+ expr_path_res, get_item_name, get_parent_expr, in_constant, is_diag_trait_item, is_integer_const, iter_input_pats,
+ last_path_segment, match_any_def_paths, paths, unsext, SpanlessEq,
};
declare_clippy_lint! {
- /// **What it does:** Checks for function arguments and let bindings denoted as
+ /// ### What it does
+ /// Checks for function arguments and let bindings denoted as
/// `ref`.
///
- /// **Why is this bad?** The `ref` declaration makes the function take an owned
+ /// ### Why is this bad?
+ /// The `ref` declaration makes the function take an owned
/// value, but turns the argument into a reference (which means that the value
/// is destroyed when exiting the function). This adds not much value: either
/// take a reference type, or take an owned value and create references in the
/// For let bindings, `let x = &foo;` is preferred over `let ref x = foo`. The
/// type of `x` is more obvious with the former.
///
- /// **Known problems:** If the argument is dereferenced within the function,
+ /// ### Known problems
+ /// If the argument is dereferenced within the function,
/// removing the `ref` will lead to errors. This can be fixed by removing the
/// dereferences, e.g., changing `*x` to `x` within the function.
///
- /// **Example:**
+ /// ### Example
/// ```rust,ignore
/// // Bad
/// fn foo(ref x: u8) -> bool {
/// true
/// }
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub TOPLEVEL_REF_ARG,
style,
"an entire binding declared as `ref`, in a function argument or a `let` statement"
}
declare_clippy_lint! {
- /// **What it does:** Checks for comparisons to NaN.
+ /// ### What it does
+ /// Checks for comparisons to NaN.
///
- /// **Why is this bad?** NaN does not compare meaningfully to anything – not
+ /// ### Why is this bad?
+ /// NaN does not compare meaningfully to anything – not
/// even itself – so those comparisons are simply wrong.
///
- /// **Known problems:** None.
- ///
- /// **Example:**
+ /// ### Example
/// ```rust
/// # let x = 1.0;
///
/// // Good
/// if x.is_nan() { }
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub CMP_NAN,
correctness,
"comparisons to `NAN`, which will always return false, probably not intended"
}
declare_clippy_lint! {
- /// **What it does:** Checks for (in-)equality comparisons on floating-point
+ /// ### What it does
+ /// Checks for (in-)equality comparisons on floating-point
/// values (apart from zero), except in functions called `*eq*` (which probably
/// implement equality for a type involving floats).
///
- /// **Why is this bad?** Floating point calculations are usually imprecise, so
+ /// ### Why is this bad?
+ /// Floating point calculations are usually imprecise, so
/// asking if two values are *exactly* equal is asking for trouble. For a good
/// guide on what to do, see [the floating point
/// guide](http://www.floating-point-gui.de/errors/comparison).
///
- /// **Known problems:** None.
- ///
- /// **Example:**
+ /// ### Example
/// ```rust
/// let x = 1.2331f64;
/// let y = 1.2332f64;
/// if (y - 1.23f64).abs() < error_margin { }
/// if (y - x).abs() > error_margin { }
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub FLOAT_CMP,
- correctness,
+ pedantic,
"using `==` or `!=` on float values instead of comparing difference with an epsilon"
}
declare_clippy_lint! {
- /// **What it does:** Checks for conversions to owned values just for the sake
+ /// ### What it does
+ /// Checks for conversions to owned values just for the sake
/// of a comparison.
///
- /// **Why is this bad?** The comparison can operate on a reference, so creating
+ /// ### Why is this bad?
+ /// The comparison can operate on a reference, so creating
/// an owned value effectively throws it away directly afterwards, which is
/// needlessly consuming code and heap space.
///
- /// **Known problems:** None.
- ///
- /// **Example:**
+ /// ### Example
/// ```rust
/// # let x = "foo";
/// # let y = String::from("foo");
/// # let y = String::from("foo");
/// if x == y {}
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub CMP_OWNED,
perf,
"creating owned instances for comparing with others, e.g., `x == \"foo\".to_string()`"
}
declare_clippy_lint! {
- /// **What it does:** Checks for getting the remainder of a division by one or minus
+ /// ### What it does
+ /// Checks for getting the remainder of a division by one or minus
/// one.
///
- /// **Why is this bad?** The result for a divisor of one can only ever be zero; for
+ /// ### Why is this bad?
+ /// The result for a divisor of one can only ever be zero; for
/// minus one it can cause panic/overflow (if the left operand is the minimal value of
/// the respective integer type) or results in zero. No one will write such code
/// deliberately, unless trying to win an Underhanded Rust Contest. Even for that
/// contest, it's probably a bad idea. Use something more underhanded.
///
- /// **Known problems:** None.
- ///
- /// **Example:**
+ /// ### Example
/// ```rust
/// # let x = 1;
/// let a = x % 1;
/// let a = x % -1;
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub MODULO_ONE,
correctness,
"taking a number modulo +/-1, which can either panic/overflow or always returns 0"
}
declare_clippy_lint! {
- /// **What it does:** Checks for the use of bindings with a single leading
+ /// ### What it does
+ /// Checks for the use of bindings with a single leading
/// underscore.
///
- /// **Why is this bad?** A single leading underscore is usually used to indicate
+ /// ### Why is this bad?
+ /// A single leading underscore is usually used to indicate
/// that a binding will not be used. Using such a binding breaks this
/// expectation.
///
- /// **Known problems:** The lint does not work properly with desugaring and
+ /// ### Known problems
+ /// The lint does not work properly with desugaring and
/// macro, it has been allowed in the mean time.
///
- /// **Example:**
+ /// ### Example
/// ```rust
/// let _x = 0;
/// let y = _x + 1; // Here we are using `_x`, even though it has a leading
/// // underscore. We should rename `_x` to `x`
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub USED_UNDERSCORE_BINDING,
pedantic,
"using a binding which is prefixed with an underscore"
}
declare_clippy_lint! {
- /// **What it does:** Checks for the use of short circuit boolean conditions as
+ /// ### What it does
+ /// Checks for the use of short circuit boolean conditions as
/// a
/// statement.
///
- /// **Why is this bad?** Using a short circuit boolean condition as a statement
+ /// ### Why is this bad?
+ /// Using a short circuit boolean condition as a statement
/// may hide the fact that the second part is executed or not depending on the
/// outcome of the first part.
///
- /// **Known problems:** None.
- ///
- /// **Example:**
+ /// ### Example
/// ```rust,ignore
/// f() && g(); // We should write `if f() { g(); }`.
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub SHORT_CIRCUIT_STATEMENT,
complexity,
"using a short circuit boolean condition as a statement"
}
declare_clippy_lint! {
- /// **What it does:** Catch casts from `0` to some pointer type
+ /// ### What it does
+ /// Catch casts from `0` to some pointer type
///
- /// **Why is this bad?** This generally means `null` and is better expressed as
+ /// ### Why is this bad?
+ /// This generally means `null` and is better expressed as
/// {`std`, `core`}`::ptr::`{`null`, `null_mut`}.
///
- /// **Known problems:** None.
- ///
- /// **Example:**
- ///
+ /// ### Example
/// ```rust
/// // Bad
/// let a = 0 as *const u32;
/// // Good
/// let a = std::ptr::null::<u32>();
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub ZERO_PTR,
style,
"using `0 as *{const, mut} T`"
}
declare_clippy_lint! {
- /// **What it does:** Checks for (in-)equality comparisons on floating-point
+ /// ### What it does
+ /// Checks for (in-)equality comparisons on floating-point
/// value and constant, except in functions called `*eq*` (which probably
/// implement equality for a type involving floats).
///
- /// **Why is this bad?** Floating point calculations are usually imprecise, so
+ /// ### Why is this bad?
+ /// Floating point calculations are usually imprecise, so
/// asking if two values are *exactly* equal is asking for trouble. For a good
/// guide on what to do, see [the floating point
/// guide](http://www.floating-point-gui.de/errors/comparison).
///
- /// **Known problems:** None.
- ///
- /// **Example:**
+ /// ### Example
/// ```rust
/// let x: f64 = 1.0;
/// const ONE: f64 = 1.00;
/// // let error_margin = std::f64::EPSILON;
/// if (x - ONE).abs() < error_margin { }
/// ```
+ #[clippy::version = "pre 1.29.0"]
pub FLOAT_CMP_CONST,
restriction,
"using `==` or `!=` on float constants instead of comparing difference with an epsilon"
if let StmtKind::Local(local) = stmt.kind;
if let PatKind::Binding(an, .., name, None) = local.pat.kind;
if let Some(init) = local.init;
- if !higher::is_from_for_desugar(local);
if an == BindingAnnotation::Ref || an == BindingAnnotation::RefMut;
then {
// use the macro callsite when the init span (but not the whole local span)
// Don't lint things expanded by #[derive(...)], etc or `await` desugaring
return;
}
+ let sym;
let binding = match expr.kind {
ExprKind::Path(ref qpath) if !matches!(qpath, hir::QPath::LangItem(..)) => {
let binding = last_path_segment(qpath).ident.as_str();
}
},
ExprKind::Field(_, ident) => {
- let name = ident.as_str();
+ sym = ident.name;
+ let name = sym.as_str();
if name.starts_with('_') && !name.starts_with("__") {
Some(name)
} else {
}
if_chain! {
- if let ExprKind::MethodCall(method_name, _, expressions, _) = expr.kind;
+ if let ExprKind::MethodCall(method_name, [ref self_arg, ..], _) = expr.kind;
if sym!(signum) == method_name.ident.name;
// Check that the receiver of the signum() is a float (expressions[0] is the receiver of
// the method call)
then {
- return is_float(cx, &expressions[0]);
+ return is_float(cx, self_arg);
}
}
false
matches!(&cx.typeck_results().expr_ty(expr).peel_refs().kind(), ty::Array(_, _))
}
+#[allow(clippy::too_many_lines)]
fn check_to_owned(cx: &LateContext<'_>, expr: &Expr<'_>, other: &Expr<'_>, left: bool) {
#[derive(Default)]
struct EqImpl {
hint = expr_snip;
} else {
span = expr.span.to(other.span);
+
+ let cmp_span = if other.span < expr.span {
+ other.span.between(expr.span)
+ } else {
+ expr.span.between(other.span)
+ };
if eq_impl.ty_eq_other {
- hint = format!("{} == {}", expr_snip, snippet(cx, other.span, ".."));
+ hint = format!(
+ "{}{}{}",
+ expr_snip,
+ snippet(cx, cmp_span, ".."),
+ snippet(cx, other.span, "..")
+ );
} else {
- hint = format!("{} == {}", snippet(cx, other.span, ".."), expr_snip);
+ hint = format!(
+ "{}{}{}",
+ snippet(cx, other.span, ".."),
+ snippet(cx, cmp_span, ".."),
+ expr_snip
+ );
}
}
use rustc_span::hygiene::MacroKind;
if expr.span.from_expansion() {
let data = expr.span.ctxt().outer_expn_data();
- matches!(
- data.kind,
- ExpnKind::Macro {
- kind: MacroKind::Attr,
- name: _,
- proc_macro: _
- }
- )
+ matches!(data.kind, ExpnKind::Macro(MacroKind::Attr, _))
} else {
false
}
}
}
-fn check_binary(
+fn check_binary<'a>(
cx: &LateContext<'a>,
expr: &Expr<'_>,
cmp: &rustc_span::source_map::Spanned<rustc_hir::BinOpKind>,