No capture optimization for find bounds and split

.gitignore

@@ -9,6 +9,7 @@ tests/tests2
 tests/tests2.js
 tests/tests_misc
 tests/tests_misc.js
+tests/test_bug
 docs/ugh
 bin/*
 bench/bench

src/regex.nim

@@ -600,12 +600,19 @@ func match*(s: string, pattern: Regex2): bool {.inline, raises: [].} =
 when defined(noRegexOpt):
   template findSomeOptTpl(s, pattern, ms, i): untyped =
     findSomeImpl(s, pattern, ms, i)
+  template findSomeOptTpl(s, pattern, ms, i, flags): untyped =
+    findSomeImpl(s, pattern, ms, i, flags)
 else:
   template findSomeOptTpl(s, pattern, ms, i): untyped =
     if pattern.litOpt.canOpt:
       findSomeOptImpl(s, pattern, ms, i)
     else:
       findSomeImpl(s, pattern, ms, i)
+  template findSomeOptTpl(s, pattern, ms, i, flags): untyped =
+    if pattern.litOpt.canOpt:
+      findSomeOptImpl(s, pattern, ms, i, flags)
+    else:
+      findSomeImpl(s, pattern, ms, i, flags)
 
 iterator findAll*(
   s: string,
@@ -668,9 +675,10 @@ iterator findAllBounds*(
   var i = start
   var i2 = start-1
   var ms: RegexMatches2
+  let flags = {mfNoCaptures}
   while i <= len(s):
     doAssert(i > i2); i2 = i
-    i = findSomeOptTpl(s, pattern.toRegex, ms, i)
+    i = findSomeOptTpl(s, pattern.toRegex, ms, i, flags)
     #debugEcho i
     if i < 0: break
     for ab in ms.bounds:
@@ -735,9 +743,10 @@ iterator split*(s: string, sep: Regex2): string {.inline, raises: [].} =
     i2 = -1
     done = false
     ms: RegexMatches2
+    flags = {mfNoCaptures}
   while not done:
     doAssert(i > i2); i2 = i
-    i = findSomeOptTpl(s, sep.toRegex, ms, i)
+    i = findSomeOptTpl(s, sep.toRegex, ms, i, flags)
     done = i < 0 or i >= len(s)
     if done: ms.dummyMatch(s.len)
     for ab in ms.bounds:

src/regex/nfafindall2.nim

@@ -173,11 +173,13 @@ func submatch(
         if matched:
           case ntn.kind
           of reGroupStart:
-            captx = capts.diverge captx
-            capts[captx, ntn.idx].a = i
+            if mfNoCaptures notin flags:
+              captx = capts.diverge captx
+              capts[captx, ntn.idx].a = i
           of reGroupEnd:
-            captx = capts.diverge captx
-            capts[captx, ntn.idx].b = i-1
+            if mfNoCaptures notin flags:
+              captx = capts.diverge captx
+              capts[captx, ntn.idx].b = i-1
           of assertionKind - lookaroundKind:
             matched = match(ntn, cPrev.Rune, c.Rune)
           of lookaroundKind:
@@ -268,7 +270,8 @@ func findSomeOptImpl*(
   text: string,
   regex: Regex,
   ms: var RegexMatches2,
-  start: Natural
+  start: Natural,
+  flags: MatchFlags = {}
 ): int =
   template regexSize: untyped =
     max(regex.litOpt.nfa.s.len, regex.nfa.s.len)
@@ -280,7 +283,7 @@ func findSomeOptImpl*(
   doAssert opt.nfa.s.len > 0
   initMaybeImpl(ms, regexSize, groupsLen)
   ms.clear()
-  let flags = regex.flags.toMatchFlags + {mfFindMatchOpt}
+  let flags = regex.flags.toMatchFlags + flags + {mfFindMatchOpt}
   let hasLits = opt.lits.len > 0
   let step = max(1, opt.lits.len)
   var limit = start.int