Import 'regex' package vesion 1.3.6

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Bug: 152884384
Test: make

Change-Id: I455caf7833b6c437c1c133bc7b2f47b83da9cbce

1 files changed, 241 insertions, 0 deletions

diff --git a/tests/consistent.rs b/tests/consistent.rs
new file mode 100644
index 0000000..0f9ea53
--- /dev/null
+++ b/tests/consistent.rs
@@ -0,0 +1,241 @@
+use regex::internal::ExecBuilder;
+
+/// Given a regex, check if all of the backends produce the same
+/// results on a number of different inputs.
+///
+/// For now this just throws quickcheck at the problem, which
+/// is not very good because it only really tests half of the
+/// problem space. It is pretty unlikely that a random string
+/// will match any given regex, so this will probably just
+/// be checking that the different backends fail in the same
+/// way. This is still worthwhile to test, but is definitely not
+/// the whole story.
+///
+/// TODO(ethan): In order to cover the other half of the problem
+/// space, we should generate a random matching string by inspecting
+/// the AST of the input regex. The right way to do this probably
+/// involves adding a custom Arbitrary instance around a couple
+/// of newtypes. That way we can respect the quickcheck size hinting
+/// and shrinking and whatnot.
+pub fn backends_are_consistent(re: &str) -> Result<u64, String> {
+    let standard_backends = vec![
+        (
+            "bounded_backtracking_re",
+            ExecBuilder::new(re)
+                .bounded_backtracking()
+                .build()
+                .map(|exec| exec.into_regex())
+                .map_err(|err| format!("{}", err))?,
+        ),
+        (
+            "pikevm_re",
+            ExecBuilder::new(re)
+                .nfa()
+                .build()
+                .map(|exec| exec.into_regex())
+                .map_err(|err| format!("{}", err))?,
+        ),
+        (
+            "default_re",
+            ExecBuilder::new(re)
+                .build()
+                .map(|exec| exec.into_regex())
+                .map_err(|err| format!("{}", err))?,
+        ),
+    ];
+
+    let utf8bytes_backends = vec![
+        (
+            "bounded_backtracking_utf8bytes_re",
+            ExecBuilder::new(re)
+                .bounded_backtracking()
+                .bytes(true)
+                .build()
+                .map(|exec| exec.into_regex())
+                .map_err(|err| format!("{}", err))?,
+        ),
+        (
+            "pikevm_utf8bytes_re",
+            ExecBuilder::new(re)
+                .nfa()
+                .bytes(true)
+                .build()
+                .map(|exec| exec.into_regex())
+                .map_err(|err| format!("{}", err))?,
+        ),
+        (
+            "default_utf8bytes_re",
+            ExecBuilder::new(re)
+                .bytes(true)
+                .build()
+                .map(|exec| exec.into_regex())
+                .map_err(|err| format!("{}", err))?,
+        ),
+    ];
+
+    let bytes_backends = vec![
+        (
+            "bounded_backtracking_bytes_re",
+            ExecBuilder::new(re)
+                .bounded_backtracking()
+                .only_utf8(false)
+                .build()
+                .map(|exec| exec.into_byte_regex())
+                .map_err(|err| format!("{}", err))?,
+        ),
+        (
+            "pikevm_bytes_re",
+            ExecBuilder::new(re)
+                .nfa()
+                .only_utf8(false)
+                .build()
+                .map(|exec| exec.into_byte_regex())
+                .map_err(|err| format!("{}", err))?,
+        ),
+        (
+            "default_bytes_re",
+            ExecBuilder::new(re)
+                .only_utf8(false)
+                .build()
+                .map(|exec| exec.into_byte_regex())
+                .map_err(|err| format!("{}", err))?,
+        ),
+    ];
+
+    Ok(string_checker::check_backends(&standard_backends)?
+        + string_checker::check_backends(&utf8bytes_backends)?
+        + bytes_checker::check_backends(&bytes_backends)?)
+}
+
+//
+// A consistency checker parameterized by the input type (&str or &[u8]).
+//
+
+macro_rules! checker {
+    ($module_name:ident, $regex_type:path, $mk_input:expr) => {
+        mod $module_name {
+            use quickcheck;
+            use quickcheck::{Arbitrary, TestResult};
+
+            pub fn check_backends(
+                backends: &[(&str, $regex_type)],
+            ) -> Result<u64, String> {
+                let mut total_passed = 0;
+                for regex in backends[1..].iter() {
+                    total_passed += quickcheck_regex_eq(&backends[0], regex)?;
+                }
+
+                Ok(total_passed)
+            }
+
+            fn quickcheck_regex_eq(
+                &(name1, ref re1): &(&str, $regex_type),
+                &(name2, ref re2): &(&str, $regex_type),
+            ) -> Result<u64, String> {
+                quickcheck::QuickCheck::new()
+                    .quicktest(RegexEqualityTest::new(
+                        re1.clone(),
+                        re2.clone(),
+                    ))
+                    .map_err(|err| {
+                        format!(
+                            "{}(/{}/) and {}(/{}/) are inconsistent.\
+                             QuickCheck Err: {:?}",
+                            name1, re1, name2, re2, err
+                        )
+                    })
+            }
+
+            struct RegexEqualityTest {
+                re1: $regex_type,
+                re2: $regex_type,
+            }
+            impl RegexEqualityTest {
+                fn new(re1: $regex_type, re2: $regex_type) -> Self {
+                    RegexEqualityTest { re1: re1, re2: re2 }
+                }
+            }
+
+            impl quickcheck::Testable for RegexEqualityTest {
+                fn result<G: quickcheck::Gen>(
+                    &self,
+                    gen: &mut G,
+                ) -> TestResult {
+                    let input = $mk_input(gen);
+                    let input = &input;
+
+                    if self.re1.find(&input) != self.re2.find(input) {
+                        return TestResult::error(format!(
+                            "find mismatch input={:?}",
+                            input
+                        ));
+                    }
+
+                    let cap1 = self.re1.captures(input);
+                    let cap2 = self.re2.captures(input);
+                    match (cap1, cap2) {
+                        (None, None) => {}
+                        (Some(cap1), Some(cap2)) => {
+                            for (c1, c2) in cap1.iter().zip(cap2.iter()) {
+                                if c1 != c2 {
+                                    return TestResult::error(format!(
+                                        "captures mismatch input={:?}",
+                                        input
+                                    ));
+                                }
+                            }
+                        }
+                        _ => {
+                            return TestResult::error(format!(
+                                "captures mismatch input={:?}",
+                                input
+                            ))
+                        }
+                    }
+
+                    let fi1 = self.re1.find_iter(input);
+                    let fi2 = self.re2.find_iter(input);
+                    for (m1, m2) in fi1.zip(fi2) {
+                        if m1 != m2 {
+                            return TestResult::error(format!(
+                                "find_iter mismatch input={:?}",
+                                input
+                            ));
+                        }
+                    }
+
+                    let ci1 = self.re1.captures_iter(input);
+                    let ci2 = self.re2.captures_iter(input);
+                    for (cap1, cap2) in ci1.zip(ci2) {
+                        for (c1, c2) in cap1.iter().zip(cap2.iter()) {
+                            if c1 != c2 {
+                                return TestResult::error(format!(
+                                    "captures_iter mismatch input={:?}",
+                                    input
+                                ));
+                            }
+                        }
+                    }
+
+                    let s1 = self.re1.split(input);
+                    let s2 = self.re2.split(input);
+                    for (chunk1, chunk2) in s1.zip(s2) {
+                        if chunk1 != chunk2 {
+                            return TestResult::error(format!(
+                                "split mismatch input={:?}",
+                                input
+                            ));
+                        }
+                    }
+
+                    TestResult::from_bool(true)
+                }
+            }
+        } // mod
+    }; // rule case
+} // macro_rules!
+
+checker!(string_checker, ::regex::Regex, |gen| String::arbitrary(gen));
+checker!(bytes_checker, ::regex::bytes::Regex, |gen| Vec::<u8>::arbitrary(
+    gen
+));