diff options
Diffstat (limited to 'src/pkg/regexp')
| -rw-r--r-- | src/pkg/regexp/all_test.go | 28 | ||||
| -rw-r--r-- | src/pkg/regexp/regexp.go | 3 |
2 files changed, 31 insertions, 0 deletions
diff --git a/src/pkg/regexp/all_test.go b/src/pkg/regexp/all_test.go index 0c274139b..05bba7376 100644 --- a/src/pkg/regexp/all_test.go +++ b/src/pkg/regexp/all_test.go @@ -454,6 +454,34 @@ func TestAllMatches(t *testing.T) { } } +type numSubexpCase struct { + input string + expected int +} + +var numSubexpCases = []numSubexpCase{ + numSubexpCase{``, 0}, + numSubexpCase{`.*`, 0}, + numSubexpCase{`abba`, 0}, + numSubexpCase{`ab(b)a`, 1}, + numSubexpCase{`ab(.*)a`, 1}, + numSubexpCase{`(.*)ab(.*)a`, 2}, + numSubexpCase{`(.*)(ab)(.*)a`, 3}, + numSubexpCase{`(.*)((a)b)(.*)a`, 4}, + numSubexpCase{`(.*)(\(ab)(.*)a`, 3}, + numSubexpCase{`(.*)(\(a\)b)(.*)a`, 3}, +} + +func TestNumSubexp(t *testing.T) { + for _, c := range numSubexpCases { + re, _ := Compile(c.input) + n := re.NumSubexp() + if n != c.expected { + t.Errorf("NumSubexp for %q returned %d, expected %d", c.input, n, c.expected) + } + } +} + func BenchmarkLiteral(b *testing.B) { x := strings.Repeat("x", 50) b.StopTimer() diff --git a/src/pkg/regexp/regexp.go b/src/pkg/regexp/regexp.go index fd6fbefee..373d6b1af 100644 --- a/src/pkg/regexp/regexp.go +++ b/src/pkg/regexp/regexp.go @@ -677,6 +677,9 @@ func MustCompile(str string) *Regexp { return regexp } +// NumSubexp returns the number of parenthesized subexpressions in this Regexp. +func (re *Regexp) NumSubexp() int { return re.nbra } + // The match arena allows us to reduce the garbage generated by tossing // match vectors away as we execute. Matches are ref counted and returned // to a free list when no longer active. Increases a simple benchmark by 22X. |