Fix diff expansion is missing final line in a file (#16222)

* Fixed down offset.

* Fixed wrong line count result.

1 files changed, 8 insertions, 3 deletions

diff --git a/modules/git/blob.go b/modules/git/blob.go
index 732356e5b2..5831bc3735 100644
--- a/modules/git/blob.go
+++ b/modules/git/blob.go
@@ -34,7 +34,7 @@ func (b *Blob) GetBlobContent() (string, error) {
 	return string(buf), nil
 }
 
-// GetBlobLineCount gets line count of lob as raw text
+// GetBlobLineCount gets line count of the blob
 func (b *Blob) GetBlobLineCount() (int, error) {
 	reader, err := b.DataAsync()
 	if err != nil {
@@ -42,10 +42,14 @@ func (b *Blob) GetBlobLineCount() (int, error) {
 	}
 	defer reader.Close()
 	buf := make([]byte, 32*1024)
-	count := 0
+	count := 1
 	lineSep := []byte{'\n'}
+
+	c, err := reader.Read(buf)
+	if c == 0 && err == io.EOF {
+		return 0, nil
+	}
 	for {
-		c, err := reader.Read(buf)
 		count += bytes.Count(buf[:c], lineSep)
 		switch {
 		case err == io.EOF:
@@ -53,6 +57,7 @@ func (b *Blob) GetBlobLineCount() (int, error) {
 		case err != nil:
 			return count, err
 		}
+		c, err = reader.Read(buf)
 	}
 }