-use clippy_utils::consts::{constant, constant_full_int, miri_to_const, FullInt};
use clippy_utils::diagnostics::{
multispan_sugg, span_lint_and_help, span_lint_and_note, span_lint_and_sugg, span_lint_and_then,
};
use rustc_hir::LangItem::{OptionNone, OptionSome};
use rustc_hir::{
self as hir, Arm, BindingAnnotation, BorrowKind, Expr, ExprKind, Local, MatchSource, Mutability, Node, Pat,
- PatKind, PathSegment, QPath, RangeEnd, TyKind,
+ PatKind, PathSegment, QPath, TyKind,
};
use rustc_lint::{LateContext, LateLintPass};
-use rustc_middle::ty::{self, Ty, VariantDef};
+use rustc_middle::ty::{self, VariantDef};
use rustc_semver::RustcVersion;
use rustc_session::{declare_tool_lint, impl_lint_pass};
-use rustc_span::{sym, symbol::kw, Span};
-use std::cmp::Ordering;
+use rustc_span::{sym, symbol::kw};
mod match_bool;
mod match_like_matches;
mod match_same_arms;
+mod overlapping_arms;
mod redundant_pattern_match;
mod single_match;
if let ExprKind::Match(ex, arms, MatchSource::Normal) = expr.kind {
single_match::check(cx, ex, arms, expr);
match_bool::check(cx, ex, arms, expr);
- check_overlapping_arms(cx, ex, arms);
+ overlapping_arms::check(cx, ex, arms);
check_wild_err_arm(cx, ex, arms);
check_wild_enum_match(cx, ex, arms);
check_match_as_ref(cx, ex, arms, expr);
extract_msrv_attr!(LateContext);
}
-fn check_overlapping_arms<'tcx>(cx: &LateContext<'tcx>, ex: &'tcx Expr<'_>, arms: &'tcx [Arm<'_>]) {
- if arms.len() >= 2 && cx.typeck_results().expr_ty(ex).is_integral() {
- let ranges = all_ranges(cx, arms, cx.typeck_results().expr_ty(ex));
- if !ranges.is_empty() {
- if let Some((start, end)) = overlapping(&ranges) {
- span_lint_and_note(
- cx,
- MATCH_OVERLAPPING_ARM,
- start.span,
- "some ranges overlap",
- Some(end.span),
- "overlaps with this",
- );
- }
- }
- }
-}
-
fn check_wild_err_arm<'tcx>(cx: &LateContext<'tcx>, ex: &Expr<'tcx>, arms: &[Arm<'tcx>]) {
let ex_ty = cx.typeck_results().expr_ty(ex).peel_refs();
if is_type_diagnostic_item(cx, ex_ty, sym::Result) {
None
}
-/// Gets the ranges for each range pattern arm. Applies `ty` bounds for open ranges.
-fn all_ranges<'tcx>(cx: &LateContext<'tcx>, arms: &'tcx [Arm<'_>], ty: Ty<'tcx>) -> Vec<SpannedRange<FullInt>> {
- arms.iter()
- .filter_map(|arm| {
- if let Arm { pat, guard: None, .. } = *arm {
- if let PatKind::Range(ref lhs, ref rhs, range_end) = pat.kind {
- let lhs_const = match lhs {
- Some(lhs) => constant(cx, cx.typeck_results(), lhs)?.0,
- None => miri_to_const(ty.numeric_min_val(cx.tcx)?)?,
- };
- let rhs_const = match rhs {
- Some(rhs) => constant(cx, cx.typeck_results(), rhs)?.0,
- None => miri_to_const(ty.numeric_max_val(cx.tcx)?)?,
- };
-
- let lhs_val = lhs_const.int_value(cx, ty)?;
- let rhs_val = rhs_const.int_value(cx, ty)?;
-
- let rhs_bound = match range_end {
- RangeEnd::Included => EndBound::Included(rhs_val),
- RangeEnd::Excluded => EndBound::Excluded(rhs_val),
- };
- return Some(SpannedRange {
- span: pat.span,
- node: (lhs_val, rhs_bound),
- });
- }
-
- if let PatKind::Lit(value) = pat.kind {
- let value = constant_full_int(cx, cx.typeck_results(), value)?;
- return Some(SpannedRange {
- span: pat.span,
- node: (value, EndBound::Included(value)),
- });
- }
- }
- None
- })
- .collect()
-}
-
-#[derive(Clone, Copy, Debug, Eq, PartialEq)]
-pub enum EndBound<T> {
- Included(T),
- Excluded(T),
-}
-
-#[derive(Debug, Eq, PartialEq)]
-struct SpannedRange<T> {
- pub span: Span,
- pub node: (T, EndBound<T>),
-}
-
// Checks if arm has the form `None => None`
fn is_none_arm(cx: &LateContext<'_>, arm: &Arm<'_>) -> bool {
matches!(arm.pat.kind, PatKind::Path(ref qpath) if is_lang_ctor(cx, qpath, OptionNone))
}
ref_count > 1
}
-
-fn overlapping<T>(ranges: &[SpannedRange<T>]) -> Option<(&SpannedRange<T>, &SpannedRange<T>)>
-where
- T: Copy + Ord,
-{
- #[derive(Copy, Clone, Debug, Eq, Ord, PartialEq, PartialOrd)]
- enum BoundKind {
- EndExcluded,
- Start,
- EndIncluded,
- }
-
- #[derive(Copy, Clone, Debug, Eq, PartialEq)]
- struct RangeBound<'a, T>(T, BoundKind, &'a SpannedRange<T>);
-
- impl<'a, T: Copy + Ord> PartialOrd for RangeBound<'a, T> {
- fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
- Some(self.cmp(other))
- }
- }
-
- impl<'a, T: Copy + Ord> Ord for RangeBound<'a, T> {
- fn cmp(&self, RangeBound(other_value, other_kind, _): &Self) -> Ordering {
- let RangeBound(self_value, self_kind, _) = *self;
- (self_value, self_kind).cmp(&(*other_value, *other_kind))
- }
- }
-
- let mut values = Vec::with_capacity(2 * ranges.len());
-
- for r @ SpannedRange { node: (start, end), .. } in ranges {
- values.push(RangeBound(*start, BoundKind::Start, r));
- values.push(match end {
- EndBound::Excluded(val) => RangeBound(*val, BoundKind::EndExcluded, r),
- EndBound::Included(val) => RangeBound(*val, BoundKind::EndIncluded, r),
- });
- }
-
- values.sort();
-
- let mut started = vec![];
-
- for RangeBound(_, kind, range) in values {
- match kind {
- BoundKind::Start => started.push(range),
- BoundKind::EndExcluded | BoundKind::EndIncluded => {
- let mut overlap = None;
-
- while let Some(last_started) = started.pop() {
- if last_started == range {
- break;
- }
- overlap = Some(last_started);
- }
-
- if let Some(first_overlapping) = overlap {
- return Some((range, first_overlapping));
- }
- },
- }
- }
-
- None
-}
-
-#[test]
-fn test_overlapping() {
- use rustc_span::source_map::DUMMY_SP;
-
- let sp = |s, e| SpannedRange {
- span: DUMMY_SP,
- node: (s, e),
- };
-
- assert_eq!(None, overlapping::<u8>(&[]));
- assert_eq!(None, overlapping(&[sp(1, EndBound::Included(4))]));
- assert_eq!(
- None,
- overlapping(&[sp(1, EndBound::Included(4)), sp(5, EndBound::Included(6))])
- );
- assert_eq!(
- None,
- overlapping(&[
- sp(1, EndBound::Included(4)),
- sp(5, EndBound::Included(6)),
- sp(10, EndBound::Included(11))
- ],)
- );
- assert_eq!(
- Some((&sp(1, EndBound::Included(4)), &sp(3, EndBound::Included(6)))),
- overlapping(&[sp(1, EndBound::Included(4)), sp(3, EndBound::Included(6))])
- );
- assert_eq!(
- Some((&sp(5, EndBound::Included(6)), &sp(6, EndBound::Included(11)))),
- overlapping(&[
- sp(1, EndBound::Included(4)),
- sp(5, EndBound::Included(6)),
- sp(6, EndBound::Included(11))
- ],)
- );
-}
--- /dev/null
+use clippy_utils::consts::{constant, constant_full_int, miri_to_const, FullInt};
+use clippy_utils::diagnostics::span_lint_and_note;
+use core::cmp::Ordering;
+use rustc_hir::{Arm, Expr, PatKind, RangeEnd};
+use rustc_lint::LateContext;
+use rustc_middle::ty::Ty;
+use rustc_span::Span;
+
+use super::MATCH_OVERLAPPING_ARM;
+
+pub(crate) fn check<'tcx>(cx: &LateContext<'tcx>, ex: &'tcx Expr<'_>, arms: &'tcx [Arm<'_>]) {
+ if arms.len() >= 2 && cx.typeck_results().expr_ty(ex).is_integral() {
+ let ranges = all_ranges(cx, arms, cx.typeck_results().expr_ty(ex));
+ if !ranges.is_empty() {
+ if let Some((start, end)) = overlapping(&ranges) {
+ span_lint_and_note(
+ cx,
+ MATCH_OVERLAPPING_ARM,
+ start.span,
+ "some ranges overlap",
+ Some(end.span),
+ "overlaps with this",
+ );
+ }
+ }
+ }
+}
+
+/// Gets the ranges for each range pattern arm. Applies `ty` bounds for open ranges.
+fn all_ranges<'tcx>(cx: &LateContext<'tcx>, arms: &'tcx [Arm<'_>], ty: Ty<'tcx>) -> Vec<SpannedRange<FullInt>> {
+ arms.iter()
+ .filter_map(|arm| {
+ if let Arm { pat, guard: None, .. } = *arm {
+ if let PatKind::Range(ref lhs, ref rhs, range_end) = pat.kind {
+ let lhs_const = match lhs {
+ Some(lhs) => constant(cx, cx.typeck_results(), lhs)?.0,
+ None => miri_to_const(ty.numeric_min_val(cx.tcx)?)?,
+ };
+ let rhs_const = match rhs {
+ Some(rhs) => constant(cx, cx.typeck_results(), rhs)?.0,
+ None => miri_to_const(ty.numeric_max_val(cx.tcx)?)?,
+ };
+
+ let lhs_val = lhs_const.int_value(cx, ty)?;
+ let rhs_val = rhs_const.int_value(cx, ty)?;
+
+ let rhs_bound = match range_end {
+ RangeEnd::Included => EndBound::Included(rhs_val),
+ RangeEnd::Excluded => EndBound::Excluded(rhs_val),
+ };
+ return Some(SpannedRange {
+ span: pat.span,
+ node: (lhs_val, rhs_bound),
+ });
+ }
+
+ if let PatKind::Lit(value) = pat.kind {
+ let value = constant_full_int(cx, cx.typeck_results(), value)?;
+ return Some(SpannedRange {
+ span: pat.span,
+ node: (value, EndBound::Included(value)),
+ });
+ }
+ }
+ None
+ })
+ .collect()
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum EndBound<T> {
+ Included(T),
+ Excluded(T),
+}
+
+#[derive(Debug, Eq, PartialEq)]
+struct SpannedRange<T> {
+ pub span: Span,
+ pub node: (T, EndBound<T>),
+}
+
+fn overlapping<T>(ranges: &[SpannedRange<T>]) -> Option<(&SpannedRange<T>, &SpannedRange<T>)>
+where
+ T: Copy + Ord,
+{
+ #[derive(Copy, Clone, Debug, Eq, Ord, PartialEq, PartialOrd)]
+ enum BoundKind {
+ EndExcluded,
+ Start,
+ EndIncluded,
+ }
+
+ #[derive(Copy, Clone, Debug, Eq, PartialEq)]
+ struct RangeBound<'a, T>(T, BoundKind, &'a SpannedRange<T>);
+
+ impl<'a, T: Copy + Ord> PartialOrd for RangeBound<'a, T> {
+ fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+ Some(self.cmp(other))
+ }
+ }
+
+ impl<'a, T: Copy + Ord> Ord for RangeBound<'a, T> {
+ fn cmp(&self, RangeBound(other_value, other_kind, _): &Self) -> Ordering {
+ let RangeBound(self_value, self_kind, _) = *self;
+ (self_value, self_kind).cmp(&(*other_value, *other_kind))
+ }
+ }
+
+ let mut values = Vec::with_capacity(2 * ranges.len());
+
+ for r @ SpannedRange { node: (start, end), .. } in ranges {
+ values.push(RangeBound(*start, BoundKind::Start, r));
+ values.push(match end {
+ EndBound::Excluded(val) => RangeBound(*val, BoundKind::EndExcluded, r),
+ EndBound::Included(val) => RangeBound(*val, BoundKind::EndIncluded, r),
+ });
+ }
+
+ values.sort();
+
+ let mut started = vec![];
+
+ for RangeBound(_, kind, range) in values {
+ match kind {
+ BoundKind::Start => started.push(range),
+ BoundKind::EndExcluded | BoundKind::EndIncluded => {
+ let mut overlap = None;
+
+ while let Some(last_started) = started.pop() {
+ if last_started == range {
+ break;
+ }
+ overlap = Some(last_started);
+ }
+
+ if let Some(first_overlapping) = overlap {
+ return Some((range, first_overlapping));
+ }
+ },
+ }
+ }
+
+ None
+}
+
+#[test]
+fn test_overlapping() {
+ use rustc_span::source_map::DUMMY_SP;
+
+ let sp = |s, e| SpannedRange {
+ span: DUMMY_SP,
+ node: (s, e),
+ };
+
+ assert_eq!(None, overlapping::<u8>(&[]));
+ assert_eq!(None, overlapping(&[sp(1, EndBound::Included(4))]));
+ assert_eq!(
+ None,
+ overlapping(&[sp(1, EndBound::Included(4)), sp(5, EndBound::Included(6))])
+ );
+ assert_eq!(
+ None,
+ overlapping(&[
+ sp(1, EndBound::Included(4)),
+ sp(5, EndBound::Included(6)),
+ sp(10, EndBound::Included(11))
+ ],)
+ );
+ assert_eq!(
+ Some((&sp(1, EndBound::Included(4)), &sp(3, EndBound::Included(6)))),
+ overlapping(&[sp(1, EndBound::Included(4)), sp(3, EndBound::Included(6))])
+ );
+ assert_eq!(
+ Some((&sp(5, EndBound::Included(6)), &sp(6, EndBound::Included(11)))),
+ overlapping(&[
+ sp(1, EndBound::Included(4)),
+ sp(5, EndBound::Included(6)),
+ sp(6, EndBound::Included(11))
+ ],)
+ );
+}
projects / rust.git / commitdiff