aboutsummaryrefslogtreecommitdiff
path: root/vendor/memchr/src/tests/packedpair.rs
diff options
context:
space:
mode:
authorValentin Popov <valentin@popov.link>2024-07-19 15:37:58 +0300
committerValentin Popov <valentin@popov.link>2024-07-19 15:37:58 +0300
commita990de90fe41456a23e58bd087d2f107d321f3a1 (patch)
tree15afc392522a9e85dc3332235e311b7d39352ea9 /vendor/memchr/src/tests/packedpair.rs
parent3d48cd3f81164bbfc1a755dc1d4a9a02f98c8ddd (diff)
downloadfparkan-a990de90fe41456a23e58bd087d2f107d321f3a1.tar.xz
fparkan-a990de90fe41456a23e58bd087d2f107d321f3a1.zip
Deleted vendor folder
Diffstat (limited to 'vendor/memchr/src/tests/packedpair.rs')
-rw-r--r--vendor/memchr/src/tests/packedpair.rs216
1 files changed, 0 insertions, 216 deletions
diff --git a/vendor/memchr/src/tests/packedpair.rs b/vendor/memchr/src/tests/packedpair.rs
deleted file mode 100644
index 204635b..0000000
--- a/vendor/memchr/src/tests/packedpair.rs
+++ /dev/null
@@ -1,216 +0,0 @@
-use alloc::{boxed::Box, vec, vec::Vec};
-
-/// A set of "packed pair" test seeds. Each seed serves as the base for the
-/// generation of many other tests. In essence, the seed captures the pair of
-/// bytes we used for a predicate and first byte among our needle. The tests
-/// generated from each seed essentially vary the length of the needle and
-/// haystack, while using the rare/first byte configuration from the seed.
-///
-/// The purpose of this is to test many different needle/haystack lengths.
-/// In particular, some of the vector optimizations might only have bugs
-/// in haystacks of a certain size.
-const SEEDS: &[Seed] = &[
- // Why not use different 'first' bytes? It seemed like a good idea to be
- // able to configure it, but when I wrote the test generator below, it
- // didn't seem necessary to use for reasons that I forget.
- Seed { first: b'x', index1: b'y', index2: b'z' },
- Seed { first: b'x', index1: b'x', index2: b'z' },
- Seed { first: b'x', index1: b'y', index2: b'x' },
- Seed { first: b'x', index1: b'x', index2: b'x' },
- Seed { first: b'x', index1: b'y', index2: b'y' },
-];
-
-/// Runs a host of "packed pair" search tests.
-///
-/// These tests specifically look for the occurrence of a possible substring
-/// match based on a pair of bytes matching at the right offsets.
-pub(crate) struct Runner {
- fwd: Option<
- Box<
- dyn FnMut(&[u8], &[u8], u8, u8) -> Option<Option<usize>> + 'static,
- >,
- >,
-}
-
-impl Runner {
- /// Create a new test runner for "packed pair" substring search.
- pub(crate) fn new() -> Runner {
- Runner { fwd: None }
- }
-
- /// Run all tests. This panics on the first failure.
- ///
- /// If the implementation being tested returns `None` for a particular
- /// haystack/needle combination, then that test is skipped.
- ///
- /// This runs tests on both the forward and reverse implementations given.
- /// If either (or both) are missing, then tests for that implementation are
- /// skipped.
- pub(crate) fn run(self) {
- if let Some(mut fwd) = self.fwd {
- for seed in SEEDS.iter() {
- for t in seed.generate() {
- match fwd(&t.haystack, &t.needle, t.index1, t.index2) {
- None => continue,
- Some(result) => {
- assert_eq!(
- t.fwd, result,
- "FORWARD, needle: {:?}, haystack: {:?}, \
- index1: {:?}, index2: {:?}",
- t.needle, t.haystack, t.index1, t.index2,
- )
- }
- }
- }
- }
- }
- }
-
- /// Set the implementation for forward "packed pair" substring search.
- ///
- /// If the closure returns `None`, then it is assumed that the given
- /// test cannot be applied to the particular implementation and it is
- /// skipped. For example, if a particular implementation only supports
- /// needles or haystacks for some minimum length.
- ///
- /// If this is not set, then forward "packed pair" search is not tested.
- pub(crate) fn fwd(
- mut self,
- search: impl FnMut(&[u8], &[u8], u8, u8) -> Option<Option<usize>> + 'static,
- ) -> Runner {
- self.fwd = Some(Box::new(search));
- self
- }
-}
-
-/// A test that represents the input and expected output to a "packed pair"
-/// search function. The test should be able to run with any "packed pair"
-/// implementation and get the expected output.
-struct Test {
- haystack: Vec<u8>,
- needle: Vec<u8>,
- index1: u8,
- index2: u8,
- fwd: Option<usize>,
-}
-
-impl Test {
- /// Create a new "packed pair" test from a seed and some given offsets to
- /// the pair of bytes to use as a predicate in the seed's needle.
- ///
- /// If a valid test could not be constructed, then None is returned.
- /// (Currently, we take the approach of massaging tests to be valid
- /// instead of rejecting them outright.)
- fn new(
- seed: Seed,
- index1: usize,
- index2: usize,
- haystack_len: usize,
- needle_len: usize,
- fwd: Option<usize>,
- ) -> Option<Test> {
- let mut index1: u8 = index1.try_into().unwrap();
- let mut index2: u8 = index2.try_into().unwrap();
- // The '#' byte is never used in a haystack (unless we're expecting
- // a match), while the '@' byte is never used in a needle.
- let mut haystack = vec![b'@'; haystack_len];
- let mut needle = vec![b'#'; needle_len];
- needle[0] = seed.first;
- needle[index1 as usize] = seed.index1;
- needle[index2 as usize] = seed.index2;
- // If we're expecting a match, then make sure the needle occurs
- // in the haystack at the expected position.
- if let Some(i) = fwd {
- haystack[i..i + needle.len()].copy_from_slice(&needle);
- }
- // If the operations above lead to rare offsets pointing to the
- // non-first occurrence of a byte, then adjust it. This might lead
- // to redundant tests, but it's simpler than trying to change the
- // generation process I think.
- if let Some(i) = crate::memchr(seed.index1, &needle) {
- index1 = u8::try_from(i).unwrap();
- }
- if let Some(i) = crate::memchr(seed.index2, &needle) {
- index2 = u8::try_from(i).unwrap();
- }
- Some(Test { haystack, needle, index1, index2, fwd })
- }
-}
-
-/// Data that describes a single prefilter test seed.
-#[derive(Clone, Copy)]
-struct Seed {
- first: u8,
- index1: u8,
- index2: u8,
-}
-
-impl Seed {
- const NEEDLE_LENGTH_LIMIT: usize = {
- #[cfg(not(miri))]
- {
- 33
- }
- #[cfg(miri)]
- {
- 5
- }
- };
-
- const HAYSTACK_LENGTH_LIMIT: usize = {
- #[cfg(not(miri))]
- {
- 65
- }
- #[cfg(miri)]
- {
- 8
- }
- };
-
- /// Generate a series of prefilter tests from this seed.
- fn generate(self) -> impl Iterator<Item = Test> {
- let len_start = 2;
- // The iterator below generates *a lot* of tests. The number of
- // tests was chosen somewhat empirically to be "bearable" when
- // running the test suite.
- //
- // We use an iterator here because the collective haystacks of all
- // these test cases add up to enough memory to OOM a conservative
- // sandbox or a small laptop.
- (len_start..=Seed::NEEDLE_LENGTH_LIMIT).flat_map(move |needle_len| {
- let index_start = len_start - 1;
- (index_start..needle_len).flat_map(move |index1| {
- (index1..needle_len).flat_map(move |index2| {
- (needle_len..=Seed::HAYSTACK_LENGTH_LIMIT).flat_map(
- move |haystack_len| {
- Test::new(
- self,
- index1,
- index2,
- haystack_len,
- needle_len,
- None,
- )
- .into_iter()
- .chain(
- (0..=(haystack_len - needle_len)).flat_map(
- move |output| {
- Test::new(
- self,
- index1,
- index2,
- haystack_len,
- needle_len,
- Some(output),
- )
- },
- ),
- )
- },
- )
- })
- })
- })
- }
-}