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-rw-r--r--vendor/regex-automata/tests/hybrid/suite.rs347
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diff --git a/vendor/regex-automata/tests/hybrid/suite.rs b/vendor/regex-automata/tests/hybrid/suite.rs
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+use {
+ anyhow::Result,
+ regex_automata::{
+ hybrid::{
+ dfa::{OverlappingState, DFA},
+ regex::{self, Regex},
+ },
+ nfa::thompson,
+ util::{prefilter::Prefilter, syntax},
+ Anchored, Input, PatternSet,
+ },
+ regex_test::{
+ CompiledRegex, Match, RegexTest, SearchKind, Span, TestResult,
+ TestRunner,
+ },
+};
+
+use crate::{create_input, suite, untestify_kind};
+
+const EXPANSIONS: &[&str] = &["is_match", "find", "which"];
+
+/// Tests the default configuration of the hybrid NFA/DFA.
+#[test]
+fn default() -> Result<()> {
+ let builder = Regex::builder();
+ TestRunner::new()?
+ .expand(EXPANSIONS, |t| t.compiles())
+ // Without NFA shrinking, this test blows the default cache capacity.
+ .blacklist("expensive/regression-many-repeat-no-stack-overflow")
+ .test_iter(suite()?.iter(), compiler(builder))
+ .assert();
+ Ok(())
+}
+
+/// Tests the hybrid NFA/DFA with prefilters enabled.
+#[test]
+fn prefilter() -> Result<()> {
+ let my_compiler = |test: &RegexTest, regexes: &[String]| {
+ // Parse regexes as HIRs so we can get literals to build a prefilter.
+ let mut hirs = vec![];
+ for pattern in regexes.iter() {
+ hirs.push(syntax::parse_with(pattern, &config_syntax(test))?);
+ }
+ let kind = match untestify_kind(test.match_kind()) {
+ None => return Ok(CompiledRegex::skip()),
+ Some(kind) => kind,
+ };
+ let pre = Prefilter::from_hirs_prefix(kind, &hirs);
+ let mut builder = Regex::builder();
+ builder.dfa(DFA::config().prefilter(pre));
+ compiler(builder)(test, regexes)
+ };
+ TestRunner::new()?
+ .expand(EXPANSIONS, |t| t.compiles())
+ // Without NFA shrinking, this test blows the default cache capacity.
+ .blacklist("expensive/regression-many-repeat-no-stack-overflow")
+ .test_iter(suite()?.iter(), my_compiler)
+ .assert();
+ Ok(())
+}
+
+/// Tests the hybrid NFA/DFA with NFA shrinking enabled.
+///
+/// This is *usually* not the configuration one wants for a lazy DFA. NFA
+/// shrinking is mostly only advantageous when building a full DFA since it
+/// can sharply decrease the amount of time determinization takes. But NFA
+/// shrinking is itself otherwise fairly expensive currently. Since a lazy DFA
+/// has no compilation time (other than for building the NFA of course) before
+/// executing a search, it's usually worth it to forgo NFA shrinking.
+///
+/// Nevertheless, we test to make sure everything is OK with NFA shrinking. As
+/// a bonus, there are some tests we don't need to skip because they now fit in
+/// the default cache capacity.
+#[test]
+fn nfa_shrink() -> Result<()> {
+ let mut builder = Regex::builder();
+ builder.thompson(thompson::Config::new().shrink(true));
+ TestRunner::new()?
+ .expand(EXPANSIONS, |t| t.compiles())
+ .test_iter(suite()?.iter(), compiler(builder))
+ .assert();
+ Ok(())
+}
+
+/// Tests the hybrid NFA/DFA when 'starts_for_each_pattern' is enabled for all
+/// tests.
+#[test]
+fn starts_for_each_pattern() -> Result<()> {
+ let mut builder = Regex::builder();
+ builder.dfa(DFA::config().starts_for_each_pattern(true));
+ TestRunner::new()?
+ .expand(EXPANSIONS, |t| t.compiles())
+ // Without NFA shrinking, this test blows the default cache capacity.
+ .blacklist("expensive/regression-many-repeat-no-stack-overflow")
+ .test_iter(suite()?.iter(), compiler(builder))
+ .assert();
+ Ok(())
+}
+
+/// Tests the hybrid NFA/DFA when 'specialize_start_states' is enabled.
+#[test]
+fn specialize_start_states() -> Result<()> {
+ let mut builder = Regex::builder();
+ builder.dfa(DFA::config().specialize_start_states(true));
+ TestRunner::new()?
+ .expand(EXPANSIONS, |t| t.compiles())
+ // Without NFA shrinking, this test blows the default cache capacity.
+ .blacklist("expensive/regression-many-repeat-no-stack-overflow")
+ .test_iter(suite()?.iter(), compiler(builder))
+ .assert();
+ Ok(())
+}
+
+/// Tests the hybrid NFA/DFA when byte classes are disabled.
+///
+/// N.B. Disabling byte classes doesn't avoid any indirection at search time.
+/// All it does is cause every byte value to be its own distinct equivalence
+/// class.
+#[test]
+fn no_byte_classes() -> Result<()> {
+ let mut builder = Regex::builder();
+ builder.dfa(DFA::config().byte_classes(false));
+ TestRunner::new()?
+ .expand(EXPANSIONS, |t| t.compiles())
+ // Without NFA shrinking, this test blows the default cache capacity.
+ .blacklist("expensive/regression-many-repeat-no-stack-overflow")
+ .test_iter(suite()?.iter(), compiler(builder))
+ .assert();
+ Ok(())
+}
+
+/// Tests that hybrid NFA/DFA never clears its cache for any test with the
+/// default capacity.
+///
+/// N.B. If a regex suite test is added that causes the cache to be cleared,
+/// then this should just skip that test. (Which can be done by calling the
+/// 'blacklist' method on 'TestRunner'.)
+#[test]
+fn no_cache_clearing() -> Result<()> {
+ let mut builder = Regex::builder();
+ builder.dfa(DFA::config().minimum_cache_clear_count(Some(0)));
+ TestRunner::new()?
+ .expand(EXPANSIONS, |t| t.compiles())
+ // Without NFA shrinking, this test blows the default cache capacity.
+ .blacklist("expensive/regression-many-repeat-no-stack-overflow")
+ .test_iter(suite()?.iter(), compiler(builder))
+ .assert();
+ Ok(())
+}
+
+/// Tests the hybrid NFA/DFA when the minimum cache capacity is set.
+#[test]
+fn min_cache_capacity() -> Result<()> {
+ let mut builder = Regex::builder();
+ builder
+ .dfa(DFA::config().cache_capacity(0).skip_cache_capacity_check(true));
+ TestRunner::new()?
+ .expand(EXPANSIONS, |t| t.compiles())
+ .test_iter(suite()?.iter(), compiler(builder))
+ .assert();
+ Ok(())
+}
+
+fn compiler(
+ mut builder: regex::Builder,
+) -> impl FnMut(&RegexTest, &[String]) -> Result<CompiledRegex> {
+ move |test, regexes| {
+ // Parse regexes as HIRs for some analysis below.
+ let mut hirs = vec![];
+ for pattern in regexes.iter() {
+ hirs.push(syntax::parse_with(pattern, &config_syntax(test))?);
+ }
+
+ // Check if our regex contains things that aren't supported by DFAs.
+ // That is, Unicode word boundaries when searching non-ASCII text.
+ if !test.haystack().is_ascii() {
+ for hir in hirs.iter() {
+ if hir.properties().look_set().contains_word_unicode() {
+ return Ok(CompiledRegex::skip());
+ }
+ }
+ }
+ if !configure_regex_builder(test, &mut builder) {
+ return Ok(CompiledRegex::skip());
+ }
+ let re = builder.build_many(&regexes)?;
+ let mut cache = re.create_cache();
+ Ok(CompiledRegex::compiled(move |test| -> TestResult {
+ run_test(&re, &mut cache, test)
+ }))
+ }
+}
+
+fn run_test(
+ re: &Regex,
+ cache: &mut regex::Cache,
+ test: &RegexTest,
+) -> TestResult {
+ let input = create_input(test);
+ match test.additional_name() {
+ "is_match" => {
+ TestResult::matched(re.is_match(cache, input.earliest(true)))
+ }
+ "find" => match test.search_kind() {
+ SearchKind::Earliest | SearchKind::Leftmost => {
+ let input =
+ input.earliest(test.search_kind() == SearchKind::Earliest);
+ TestResult::matches(
+ re.find_iter(cache, input)
+ .take(test.match_limit().unwrap_or(std::usize::MAX))
+ .map(|m| Match {
+ id: m.pattern().as_usize(),
+ span: Span { start: m.start(), end: m.end() },
+ }),
+ )
+ }
+ SearchKind::Overlapping => {
+ try_search_overlapping(re, cache, &input).unwrap()
+ }
+ },
+ "which" => match test.search_kind() {
+ SearchKind::Earliest | SearchKind::Leftmost => {
+ // There are no "which" APIs for standard searches.
+ TestResult::skip()
+ }
+ SearchKind::Overlapping => {
+ let dfa = re.forward();
+ let cache = cache.as_parts_mut().0;
+ let mut patset = PatternSet::new(dfa.pattern_len());
+ dfa.try_which_overlapping_matches(cache, &input, &mut patset)
+ .unwrap();
+ TestResult::which(patset.iter().map(|p| p.as_usize()))
+ }
+ },
+ name => TestResult::fail(&format!("unrecognized test name: {}", name)),
+ }
+}
+
+/// Configures the given regex builder with all relevant settings on the given
+/// regex test.
+///
+/// If the regex test has a setting that is unsupported, then this returns
+/// false (implying the test should be skipped).
+fn configure_regex_builder(
+ test: &RegexTest,
+ builder: &mut regex::Builder,
+) -> bool {
+ let match_kind = match untestify_kind(test.match_kind()) {
+ None => return false,
+ Some(k) => k,
+ };
+
+ let mut dfa_config =
+ DFA::config().match_kind(match_kind).unicode_word_boundary(true);
+ // When doing an overlapping search, we might try to find the start of each
+ // match with a custom search routine. In that case, we need to tell the
+ // reverse search (for the start offset) which pattern to look for. The
+ // only way that API works is when anchored starting states are compiled
+ // for each pattern. This does technically also enable it for the forward
+ // DFA, but we're okay with that.
+ if test.search_kind() == SearchKind::Overlapping {
+ dfa_config = dfa_config.starts_for_each_pattern(true);
+ }
+ builder
+ .syntax(config_syntax(test))
+ .thompson(config_thompson(test))
+ .dfa(dfa_config);
+ true
+}
+
+/// Configuration of a Thompson NFA compiler from a regex test.
+fn config_thompson(test: &RegexTest) -> thompson::Config {
+ let mut lookm = regex_automata::util::look::LookMatcher::new();
+ lookm.set_line_terminator(test.line_terminator());
+ thompson::Config::new().utf8(test.utf8()).look_matcher(lookm)
+}
+
+/// Configuration of the regex parser from a regex test.
+fn config_syntax(test: &RegexTest) -> syntax::Config {
+ syntax::Config::new()
+ .case_insensitive(test.case_insensitive())
+ .unicode(test.unicode())
+ .utf8(test.utf8())
+ .line_terminator(test.line_terminator())
+}
+
+/// Execute an overlapping search, and for each match found, also find its
+/// overlapping starting positions.
+///
+/// N.B. This routine used to be part of the crate API, but 1) it wasn't clear
+/// to me how useful it was and 2) it wasn't clear to me what its semantics
+/// should be. In particular, a potentially surprising footgun of this routine
+/// that it is worst case *quadratic* in the size of the haystack. Namely, it's
+/// possible to report a match at every position, and for every such position,
+/// scan all the way to the beginning of the haystack to find the starting
+/// position. Typical leftmost non-overlapping searches don't suffer from this
+/// because, well, matches can't overlap. So subsequent searches after a match
+/// is found don't revisit previously scanned parts of the haystack.
+///
+/// Its semantics can be strange for other reasons too. For example, given
+/// the regex '.*' and the haystack 'zz', the full set of overlapping matches
+/// is: [0, 0], [1, 1], [0, 1], [2, 2], [1, 2], [0, 2]. The ordering of
+/// those matches is quite strange, but makes sense when you think about the
+/// implementation: an end offset is found left-to-right, and then one or more
+/// starting offsets are found right-to-left.
+///
+/// Nevertheless, we provide this routine in our test suite because it's
+/// useful to test the low level DFA overlapping search and our test suite
+/// is written in a way that requires starting offsets.
+fn try_search_overlapping(
+ re: &Regex,
+ cache: &mut regex::Cache,
+ input: &Input<'_>,
+) -> Result<TestResult> {
+ let mut matches = vec![];
+ let mut fwd_state = OverlappingState::start();
+ let (fwd_dfa, rev_dfa) = (re.forward(), re.reverse());
+ let (fwd_cache, rev_cache) = cache.as_parts_mut();
+ while let Some(end) = {
+ fwd_dfa.try_search_overlapping_fwd(
+ fwd_cache,
+ input,
+ &mut fwd_state,
+ )?;
+ fwd_state.get_match()
+ } {
+ let revsearch = input
+ .clone()
+ .range(input.start()..end.offset())
+ .anchored(Anchored::Pattern(end.pattern()))
+ .earliest(false);
+ let mut rev_state = OverlappingState::start();
+ while let Some(start) = {
+ rev_dfa.try_search_overlapping_rev(
+ rev_cache,
+ &revsearch,
+ &mut rev_state,
+ )?;
+ rev_state.get_match()
+ } {
+ let span = Span { start: start.offset(), end: end.offset() };
+ let mat = Match { id: end.pattern().as_usize(), span };
+ matches.push(mat);
+ }
+ }
+ Ok(TestResult::matches(matches))
+}