Fix the regex again

commenter/commenter.go

@@ -17,7 +17,7 @@ type Commenter struct {
 }
 
 var (
-	patchRegex     = regexp.MustCompile(`^@@.*[\+\-](\d+)(?>\s[\+\-](\d)|,(\d+)).+?@@`)
+	patchRegex     = regexp.MustCompile(`^@@.*\d [\+\-](\d+),?(\d+)?.+?@@`)
 	commitRefRegex = regexp.MustCompile(".+ref=(.+)")
 )
 
@@ -193,19 +193,39 @@ func buildComment(file, comment string, line int, info commitFileInfo) *github.P
 }
 
 func getCommitInfo(file *github.CommitFile) (cfi *commitFileInfo, err error) {
-	var hunkStart, hunkEnd int
 	var isBinary bool
 	patch := file.GetPatch()
+	hunkStart, hunkEnd, err := parseHunkPositions(patch, *file.Filename)
+	if err != nil {
+		return nil, err
+	}
+
+	shaGroups := commitRefRegex.FindAllStringSubmatch(file.GetContentsURL(), -1)
+	if len(shaGroups) < 1 {
+		return nil, fmt.Errorf("the sha details for [%s] could not be resolved", *file.Filename)
+	}
+	sha := shaGroups[0][1]
+
+	return &commitFileInfo{
+		FileName:     *file.Filename,
+		hunkStart:    hunkStart,
+		hunkEnd:      hunkStart + (hunkEnd - 1),
+		sha:          sha,
+		likelyBinary: isBinary,
+	}, nil
+}
+
+func parseHunkPositions(patch, filename string) (hunkStart int, hunkEnd int, err error) {
 	if patch != "" {
 		groups := patchRegex.FindAllStringSubmatch(patch, -1)
 		if len(groups) < 1 {
-			return nil, fmt.Errorf("the patch details for [%s] could not be resolved", *file.Filename)
+			return 0, 0, fmt.Errorf("the patch details for [%s] could not be resolved", filename)
 		}
 
 		patchGroup := groups[0]
 		endPos := 2
-		if len(patchGroup) > 2 {
-			endPos = 3
+		if len(patchGroup) > 2 && patchGroup[2] == "" {
+			endPos = 1
 		}
 
 		hunkStart, err = strconv.Atoi(patchGroup[1])
@@ -217,18 +237,5 @@ func getCommitInfo(file *github.CommitFile) (cfi *commitFileInfo, err error) {
 			hunkEnd = -1
 		}
 	}
-
-	shaGroups := commitRefRegex.FindAllStringSubmatch(file.GetContentsURL(), -1)
-	if len(shaGroups) < 1 {
-		return nil, fmt.Errorf("the sha details for [%s] could not be resolved", *file.Filename)
-	}
-	sha := shaGroups[0][1]
-
-	return &commitFileInfo{
-		FileName:     *file.Filename,
-		hunkStart:    hunkStart,
-		hunkEnd:      hunkStart + (hunkEnd - 1),
-		sha:          sha,
-		likelyBinary: isBinary,
-	}, nil
+	return hunkStart, hunkEnd, nil
 }