From fa1b74d4fc904a8af6ccdbfd723658d03d5d31bc Mon Sep 17 00:00:00 2001
From: Eng Zer Jun <engzerjun@gmail.com>
Date: Wed, 25 Oct 2023 03:23:17 +0800
Subject: [PATCH] Avoid allocations with `(*regexp.Regexp).MatchString`
We should use `(*regexp.Regexp).MatchString` instead of
`(*regexp.Regexp).Match([]byte(...))` when matching string to avoid
unnecessary `[]byte` conversions and reduce allocations.
Example benchmark:
var defaultTagRegex = regexp.MustCompile("\n *#nosec")
func BenchmarkMatch(b *testing.B) {
for i := 0; i < b.N; i++ {
if match := defaultTagRegex.Match([]byte("\n #nosec")); !match {
b.Fail()
}
}
}
func BenchmarkMatchString(b *testing.B) {
for i := 0; i < b.N; i++ {
if match := defaultTagRegex.MatchString("\n #nosec"); !match {
b.Fail()
}
}
}
goos: linux
goarch: amd64
pkg: github.com/securego/gosec/v2
cpu: AMD Ryzen 7 PRO 4750U with Radeon Graphics
BenchmarkMatch-16 5367033 210.6 ns/op 8 B/op 1 allocs/op
BenchmarkMatchString-16 9321561 126.3 ns/op 0 B/op 0 allocs/op
PASS
ok github.com/securego/gosec/v2 3.606s
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
---
analyzer.go | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/analyzer.go b/analyzer.go
index 1fd1f56..bcb9143 100644
--- a/analyzer.go
+++ b/analyzer.go
@@ -557,8 +557,8 @@ func (gosec *Analyzer) ignore(n ast.Node) map[string]issue.SuppressionInfo {
for _, group := range groups {
comment := strings.TrimSpace(group.Text())
- foundDefaultTag := strings.HasPrefix(comment, noSecDefaultTag) || regexp.MustCompile("\n *"+noSecDefaultTag).Match([]byte(comment))
- foundAlternativeTag := strings.HasPrefix(comment, noSecAlternativeTag) || regexp.MustCompile("\n *"+noSecAlternativeTag).Match([]byte(comment))
+ foundDefaultTag := strings.HasPrefix(comment, noSecDefaultTag) || regexp.MustCompile("\n *"+noSecDefaultTag).MatchString(comment)
+ foundAlternativeTag := strings.HasPrefix(comment, noSecAlternativeTag) || regexp.MustCompile("\n *"+noSecAlternativeTag).MatchString(comment)
if foundDefaultTag || foundAlternativeTag {
gosec.stats.NumNosec++