Skip to content

Fix a bug in capture with match #561

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
wants to merge 2 commits into from
Closed

Fix a bug in capture with match #561

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
7fa0b1c
Fix a bug in capture with match
hikotq Mar 10, 2019
0800bc3
formatting
hikotq Mar 10, 2019
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
7 changes: 4 additions & 3 deletions src/backtrack.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -98,6 +98,7 @@ impl<'a, 'm, 'r, 's, I: Input> Bounded<'a, 'm, 'r, 's, I> {
slots: &'s mut [Slot],
input: I,
start: usize,
end: usize,
) -> bool {
let mut cache = cache.borrow_mut();
let cache = &mut cache.backtrack;
Expand All @@ -109,7 +110,7 @@ impl<'a, 'm, 'r, 's, I: Input> Bounded<'a, 'm, 'r, 's, I> {
slots: slots,
m: cache,
};
b.exec_(start)
b.exec_(start, end)
}

/// Clears the cache such that the backtracking engine can be executed
Expand Down Expand Up @@ -147,7 +148,7 @@ impl<'a, 'm, 'r, 's, I: Input> Bounded<'a, 'm, 'r, 's, I> {

/// Start backtracking at the given position in the input, but also look
/// for literal prefixes.
fn exec_(&mut self, mut at: InputAt) -> bool {
fn exec_(&mut self, mut at: InputAt, end: usize) -> bool {
self.clear();
// If this is an anchored regex at the beginning of the input, then
// we're either already done or we only need to try backtracking once.
Expand All @@ -170,7 +171,7 @@ impl<'a, 'm, 'r, 's, I: Input> Bounded<'a, 'm, 'r, 's, I> {
if matched && self.prog.matches.len() == 1 {
return true;
}
if at.is_end() {
if at.pos() == end {
break;
}
at = self.input.at(at.next_pos());
Expand Down
90 changes: 51 additions & 39 deletions src/exec.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -10,7 +10,6 @@

use std::cell::RefCell;
use std::collections::HashMap;
use std::cmp;
use std::sync::Arc;

use thread_local::CachedThreadLocal;
Expand Down Expand Up @@ -557,7 +556,8 @@ impl<'c> RegularExpression for ExecNoSync<'c> {
match self.ro.match_type {
MatchType::Literal(ty) => {
self.find_literals(ty, text, start).and_then(|(s, e)| {
self.captures_nfa_with_match(slots, text, s, e)
self.captures_nfa_type(
MatchNfaType::Auto, slots, text, s, e)
})
}
MatchType::Dfa => {
Expand All @@ -566,7 +566,8 @@ impl<'c> RegularExpression for ExecNoSync<'c> {
} else {
match self.find_dfa_forward(text, start) {
dfa::Result::Match((s, e)) => {
self.captures_nfa_with_match(slots, text, s, e)
self.captures_nfa_type(
MatchNfaType::Auto, slots, text, s, e)
}
dfa::Result::NoMatch(_) => None,
dfa::Result::Quit => self.captures_nfa(slots, text, start),
Expand All @@ -576,7 +577,8 @@ impl<'c> RegularExpression for ExecNoSync<'c> {
MatchType::DfaAnchoredReverse => {
match self.find_dfa_anchored_reverse(text, start) {
dfa::Result::Match((s, e)) => {
self.captures_nfa_with_match(slots, text, s, e)
self.captures_nfa_type(
MatchNfaType::Auto, slots, text, s, e)
}
dfa::Result::NoMatch(_) => None,
dfa::Result::Quit => self.captures_nfa(slots, text, start),
Expand All @@ -585,14 +587,15 @@ impl<'c> RegularExpression for ExecNoSync<'c> {
MatchType::DfaSuffix => {
match self.find_dfa_reverse_suffix(text, start) {
dfa::Result::Match((s, e)) => {
self.captures_nfa_with_match(slots, text, s, e)
self.captures_nfa_type(
MatchNfaType::Auto, slots, text, s, e)
}
dfa::Result::NoMatch(_) => None,
dfa::Result::Quit => self.captures_nfa(slots, text, start),
}
}
MatchType::Nfa(ty) => {
self.captures_nfa_type(ty, slots, text, start)
self.captures_nfa_type(ty, slots, text, start, text.len())
}
MatchType::Nothing => None,
MatchType::DfaMany => {
Expand Down Expand Up @@ -830,7 +833,7 @@ impl<'c> ExecNoSync<'c> {
text: &[u8],
start: usize,
) -> bool {
self.exec_nfa(ty, &mut [false], &mut [], true, text, start)
self.exec_nfa(ty, &mut [false], &mut [], true, text, start, text.len())
}

/// Finds the shortest match using an NFA.
Expand All @@ -846,7 +849,15 @@ impl<'c> ExecNoSync<'c> {
start: usize,
) -> Option<usize> {
let mut slots = [None, None];
if self.exec_nfa(ty, &mut [false], &mut slots, true, text, start) {
if self.exec_nfa(
ty,
&mut [false],
&mut slots,
true,
text,
start,
text.len()
) {
slots[1]
} else {
None
Expand All @@ -861,7 +872,15 @@ impl<'c> ExecNoSync<'c> {
start: usize,
) -> Option<(usize, usize)> {
let mut slots = [None, None];
if self.exec_nfa(ty, &mut [false], &mut slots, false, text, start) {
if self.exec_nfa(
ty,
&mut [false],
&mut slots,
false,
text,
start,
text.len()
) {
match (slots[0], slots[1]) {
(Some(s), Some(e)) => Some((s, e)),
_ => None,
Expand All @@ -871,26 +890,6 @@ impl<'c> ExecNoSync<'c> {
}
}

/// Like find_nfa, but fills in captures and restricts the search space
/// using previously found match information.
///
/// `slots` should have length equal to `2 * nfa.captures.len()`.
fn captures_nfa_with_match(
&self,
slots: &mut [Slot],
text: &[u8],
match_start: usize,
match_end: usize,
) -> Option<(usize, usize)> {
// We can't use match_end directly, because we may need to examine one
// "character" after the end of a match for lookahead operators. We
// need to move two characters beyond the end, since some look-around
// operations may falsely assume a premature end of text otherwise.
let e = cmp::min(
next_utf8(text, next_utf8(text, match_end)), text.len());
self.captures_nfa(slots, &text[..e], match_start)
}

/// Like find_nfa, but fills in captures.
///
/// `slots` should have length equal to `2 * nfa.captures.len()`.
Expand All @@ -900,7 +899,8 @@ impl<'c> ExecNoSync<'c> {
text: &[u8],
start: usize,
) -> Option<(usize, usize)> {
self.captures_nfa_type(MatchNfaType::Auto, slots, text, start)
self.captures_nfa_type(
MatchNfaType::Auto, slots, text, start, text.len())
}

/// Like captures_nfa, but allows specification of type of NFA engine.
Expand All @@ -910,8 +910,9 @@ impl<'c> ExecNoSync<'c> {
slots: &mut [Slot],
text: &[u8],
start: usize,
end: usize,
) -> Option<(usize, usize)> {
if self.exec_nfa(ty, &mut [false], slots, false, text, start) {
if self.exec_nfa(ty, &mut [false], slots, false, text, start, end) {
match (slots[0], slots[1]) {
(Some(s), Some(e)) => Some((s, e)),
_ => None,
Expand All @@ -929,6 +930,7 @@ impl<'c> ExecNoSync<'c> {
quit_after_match: bool,
text: &[u8],
start: usize,
end: usize,
) -> bool {
use self::MatchNfaType::*;
if let Auto = ty {
Expand All @@ -940,10 +942,10 @@ impl<'c> ExecNoSync<'c> {
}
match ty {
Auto => unreachable!(),
Backtrack => self.exec_backtrack(matches, slots, text, start),
Backtrack => self.exec_backtrack(matches, slots, text, start, end),
PikeVM => {
self.exec_pikevm(
matches, slots, quit_after_match, text, start)
matches, slots, quit_after_match, text, start, end)
}
}
}
Expand All @@ -956,6 +958,7 @@ impl<'c> ExecNoSync<'c> {
quit_after_match: bool,
text: &[u8],
start: usize,
end: usize,
) -> bool {
if self.ro.nfa.uses_bytes() {
pikevm::Fsm::exec(
Expand All @@ -965,7 +968,8 @@ impl<'c> ExecNoSync<'c> {
slots,
quit_after_match,
ByteInput::new(text, self.ro.nfa.only_utf8),
start)
start,
end)
} else {
pikevm::Fsm::exec(
&self.ro.nfa,
Expand All @@ -974,7 +978,8 @@ impl<'c> ExecNoSync<'c> {
slots,
quit_after_match,
CharInput::new(text),
start)
start,
end)
}
}

Expand All @@ -985,6 +990,7 @@ impl<'c> ExecNoSync<'c> {
slots: &mut [Slot],
text: &[u8],
start: usize,
end: usize,
) -> bool {
if self.ro.nfa.uses_bytes() {
backtrack::Bounded::exec(
Expand All @@ -993,15 +999,17 @@ impl<'c> ExecNoSync<'c> {
matches,
slots,
ByteInput::new(text, self.ro.nfa.only_utf8),
start)
start,
end)
} else {
backtrack::Bounded::exec(
&self.ro.nfa,
self.cache,
matches,
slots,
CharInput::new(text),
start)
start,
end)
}
}

Expand Down Expand Up @@ -1045,11 +1053,15 @@ impl<'c> ExecNoSync<'c> {
&mut [],
false,
text,
start)
start,
text.len())
}
}
}
Nfa(ty) => self.exec_nfa(ty, matches, &mut [], false, text, start),
Nfa(ty) => {
self.exec_nfa(
ty, matches, &mut [], false, text, start, text.len())
}
Nothing => false,
}
}
Expand Down
5 changes: 4 additions & 1 deletion src/pikevm.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -107,6 +107,7 @@ impl<'r, I: Input> Fsm<'r, I> {
quit_after_match: bool,
input: I,
start: usize,
end: usize,
) -> bool {
let mut cache = cache.borrow_mut();
let cache = &mut cache.pikevm;
Expand All @@ -124,6 +125,7 @@ impl<'r, I: Input> Fsm<'r, I> {
slots,
quit_after_match,
at,
end,
)
}

Expand All @@ -135,6 +137,7 @@ impl<'r, I: Input> Fsm<'r, I> {
slots: &mut [Slot],
quit_after_match: bool,
mut at: InputAt,
end: usize,
) -> bool {
let mut matched = false;
let mut all_matched = false;
Expand Down Expand Up @@ -212,7 +215,7 @@ impl<'r, I: Input> Fsm<'r, I> {
}
}
}
if at.is_end() {
if at.pos() == end {
break;
}
at = at_next;
Expand Down
7 changes: 6 additions & 1 deletion tests/regression.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -88,8 +88,13 @@ ismatch!(reverse_suffix2, r"\d\d\d000", "153.230000\n", true);
matiter!(reverse_suffix3, r"\d\d\d000", "153.230000\n", (4, 10));

// See: https://github.com/rust-lang/regex/issues/334
mat!(captures_after_dfa_premature_end, r"a(b*(X|$))?", "abcbX",
// See: https://github.com/rust-lang/regex/issues/557
mat!(captures_after_dfa_premature_end1, r"a(b*(X|$))?", "abcbX",
Some((0, 1)), None, None);
mat!(captures_after_dfa_premature_end2, r"a(bc*(X|$))?", "abcbX",
Some((0, 1)), None, None);
mat!(captures_after_dfa_premature_end3, r"(aa$)?", "aaz",
Some((0, 0)));

// See: https://github.com/rust-lang/regex/issues/437
ismatch!(
Expand Down