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|
//! Test the computation of arm intersections.
use common::*;
use rustc_pattern_analysis::MatchArm;
use rustc_pattern_analysis::pat::DeconstructedPat;
use rustc_pattern_analysis::usefulness::PlaceValidity;
#[macro_use]
mod common;
/// Analyze a match made of these patterns and returns the computed arm intersections.
fn check(patterns: Vec<DeconstructedPat<Cx>>) -> Vec<Vec<usize>> {
let ty = *patterns[0].ty();
let arms: Vec<_> =
patterns.iter().map(|pat| MatchArm { pat, has_guard: false, arm_data: () }).collect();
let report =
compute_match_usefulness(arms.as_slice(), ty, PlaceValidity::ValidOnly, None).unwrap();
report.arm_intersections.into_iter().map(|bitset| bitset.iter().collect()).collect()
}
#[track_caller]
fn assert_intersects(patterns: Vec<DeconstructedPat<Cx>>, intersects: &[&[usize]]) {
let computed_intersects = check(patterns);
assert_eq!(computed_intersects, intersects);
}
#[test]
fn test_int_ranges() {
let ty = Ty::U8;
assert_intersects(
pats!(ty;
0..=100,
100..,
),
&[&[], &[0]],
);
assert_intersects(
pats!(ty;
0..=101,
100..,
),
&[&[], &[0]],
);
assert_intersects(
pats!(ty;
0..100,
100..,
),
&[&[], &[]],
);
}
#[test]
fn test_nested() {
let ty = Ty::Tuple(&[Ty::Bool; 2]);
assert_intersects(
pats!(ty;
(true, true),
(true, _),
(_, true),
),
&[&[], &[0], &[0, 1]],
);
// Here we shortcut because `(true, true)` is irrelevant, so we fail to detect the intersection.
assert_intersects(
pats!(ty;
(true, _),
(_, true),
),
&[&[], &[]],
);
let ty = Ty::Tuple(&[Ty::Bool; 3]);
assert_intersects(
pats!(ty;
(true, true, _),
(true, _, true),
(false, _, _),
),
&[&[], &[], &[]],
);
let ty = Ty::Tuple(&[Ty::Bool, Ty::Bool, Ty::U8]);
assert_intersects(
pats!(ty;
(true, _, _),
(_, true, 0..10),
(_, true, 10..),
(_, true, 3),
_,
),
&[&[], &[], &[], &[1], &[0, 1, 2, 3]],
);
}
|
