perf(debian): use bytes.Index in emptyLineSplit to cut allocation (#7065)

paulcacheux · web-flow · commit acbec053c985 · 2024-07-02T06:11:09.000Z
diff --git a/pkg/fanal/analyzer/pkg/dpkg/scanner.go b/pkg/fanal/analyzer/pkg/dpkg/scanner.go
@@ -5,7 +5,6 @@ import (
 	"bytes"
 	"io"
 	"net/textproto"
-	"strings"
 )
 
 type dpkgScanner struct {
@@ -42,7 +41,7 @@ func emptyLineSplit(data []byte, atEOF bool) (advance int, token []byte, err err
 		return 0, nil, nil
 	}
 
-	if i := strings.Index(string(data), "\n\n"); i >= 0 {
+	if i := bytes.Index(data, []byte("\n\n")); i >= 0 {
 		// We have a full empty line terminated block.
 		return i + 2, data[0:i], nil
 	}

Original file line number	Diff line number	Diff line change
`@@ -5,7 +5,6 @@ import (`
`5`	`5`	`"bytes"`
`6`	`6`	`"io"`
`7`	`7`	`"net/textproto"`
`8`		`- "strings"`
`9`	`8`	`)`
`10`	`9`
`11`	`10`	`type dpkgScanner struct {`
`@@ -42,7 +41,7 @@ func emptyLineSplit(data []byte, atEOF bool) (advance int, token []byte, err err`
`42`	`41`	`return 0, nil, nil`
`43`	`42`	`}`
`44`	`43`
`45`		`- if i := strings.Index(string(data), "\n\n"); i >= 0 {`
	`44`	`+ if i := bytes.Index(data, []byte("\n\n")); i >= 0 {`
`46`	`45`	`// We have a full empty line terminated block.`
`47`	`46`	`return i + 2, data[0:i], nil`
`48`	`47`	`}`