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Replace Constant::partial_cmp

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This commit is contained in:
Michael Wright
2018-06-19 07:37:09 +02:00
parent 7a32c28931
commit 0f83c68698
2 changed files with 24 additions and 28 deletions
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21
clippy_lints/src/minmax.rs
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@@ -1,9 +1,8 @@
use crate::consts::{constant_simple, Constant};
use crate::utils::{match_def_path, opt_def_id, paths, sext, span_lint};
use crate::utils::{match_def_path, opt_def_id, paths, span_lint};
use rustc::hir::*;
use rustc::lint::*;
use rustc::ty::{self, TyCtxt};
use std::cmp::{Ordering, PartialOrd};
use std::cmp::Ordering;
/// **What it does:** Checks for expressions where `std::cmp::min` and `max` are
/// used to clamp values, but switched so that the result is constant.
@@ -43,7 +42,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MinMaxPass {
}
match (
outer_max,
const_partial_cmp(cx.tcx, &outer_c, &inner_c, &cx.tables.expr_ty(ie).sty),
Constant::partial_cmp(cx.tcx, &cx.tables.expr_ty(ie).sty, &outer_c, &inner_c),
) {
(_, None) | (MinMax::Max, Some(Ordering::Less)) | (MinMax::Min, Some(Ordering::Greater)) => (),
_ => {
@@ -60,20 +59,6 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MinMaxPass {
}
}
// Constant::partial_cmp incorrectly orders signed integers
fn const_partial_cmp(tcx: TyCtxt, a: &Constant, b: &Constant, expr_ty: &ty::TypeVariants) -> Option<Ordering> {
match *expr_ty {
ty::TyInt(int_ty) => {
if let (&Constant::Int(a), &Constant::Int(b)) = (a, b) {
Some(sext(tcx, a, int_ty).cmp(&sext(tcx, b, int_ty)))
} else {
None
}
},
_ => a.partial_cmp(&b),
}
}
#[derive(PartialEq, Eq, Debug)]
enum MinMax {
Min,