build(rust): vendor googletest crate

third_party/crates/regex-automata-0.4.18/tests/nfa/thompson/backtrack/regression.rs

@@ -0,0 +1,20 @@
+// Tests that we can call the backtracker with more slots
+// than is actually in the compiled regex.
+#[test]
+fn too_many_slots_normal_pattern() {
+    use regex_automata::{
+        nfa::thompson::backtrack::BoundedBacktracker,
+        util::primitives::NonMaxUsize, Anchored, Input,
+    };
+
+    let expr = BoundedBacktracker::new(r"abc").unwrap();
+    let s = "abc";
+    let input = Input::new(s).span(0..s.len()).anchored(Anchored::Yes);
+
+    let mut cache = expr.create_cache();
+    let mut slots: Vec<Option<NonMaxUsize>> = vec![None; 4];
+    let pid = expr.try_search_slots(&mut cache, &input, &mut slots).unwrap();
+    assert_eq!(pid, Some(regex_automata::PatternID::must(0)));
+    assert_eq!(slots[0], Some(NonMaxUsize::new(0).unwrap()));
+    assert_eq!(slots[1], Some(NonMaxUsize::new(3).unwrap()));
+}