use clippy_utils::SpanlessEq;

use clippy_utils::diagnostics::span_lint_and_sugg;

use clippy_utils::source::snippet_with_applicability;

use rustc_ast::LitKind;

use rustc_data_structures::packed::Pu128;

use rustc_errors::Applicability;

use rustc_hir::{BinOpKind, Expr, ExprKind};

use rustc_lint::{LateContext, LateLintPass};

use rustc_middle::ty::Uint;

use rustc_session::declare_lint_pass;

declare_clippy_lint! {

/// ### What it does

/// Checks for expressions like `x.count_ones() == 1` or `x & (x - 1) == 0`, with x and unsigned integer, which may be manual

/// reimplementations of `x.is_power_of_two()`.

///

/// ### Why is this bad?

/// Manual reimplementations of `is_power_of_two` increase code complexity for little benefit.

///

/// ### Example

/// ```no_run

/// let a: u32 = 4;

/// let result = a.count_ones() == 1;

/// ```

/// Use instead:

/// ```no_run

/// let a: u32 = 4;

/// let result = a.is_power_of_two();

/// ```

#[clippy::version = "1.83.0"]

pub MANUAL_IS_POWER_OF_TWO,

pedantic,

"manually reimplementing `is_power_of_two`"

}

declare_lint_pass!(ManualIsPowerOfTwo => [MANUAL_IS_POWER_OF_TWO]);

impl LateLintPass<'_> for ManualIsPowerOfTwo {

}

fn build_sugg(cx: &LateContext<'_>, expr: &Expr<'_>, receiver: &Expr<'_>, applicability: &mut Applicability) {

}

fn check_lit(expr: &Expr<'_>, expected_num: u128) -> bool {

}

fn check_eq_expr(cx: &LateContext<'_>, lhs: &Expr<'_>, rhs: &Expr<'_>) -> bool {

SpanlessEq::new(cx).eq_expr(lhs, rhs)

}