fix: add offest with // comment

Author: ldez

pkg/golinters/goheader/goheader.go

@@ -76,8 +76,20 @@ func runGoHeader(pass *analysis.Pass, conf *goheader.Configuration) error {
 
 		f := pass.Fset.File(file.Pos())
 
+		commentLine := 1
+		var offset int
+
+		// Inspired by https://github.com/denis-tingaikin/go-header/blob/4c75a6a2332f025705325d6c71fff4616aedf48f/analyzer.go#L85-L92
+		if len(file.Comments) > 0 && file.Comments[0].Pos() < file.Package {
+			if !strings.HasPrefix(file.Comments[0].List[0].Text, "/*") {
+				// When the comment are "//" there is a one character offset.
+				offset = 1
+			}
+			commentLine = goanalysis.GetFilePositionFor(pass.Fset, file.Comments[0].Pos()).Line
+		}
+
 		diag := analysis.Diagnostic{
-			Pos:     f.LineStart(issue.Location().Line+1) + token.Pos(issue.Location().Position), // The position of the first divergence.
+			Pos:     f.LineStart(issue.Location().Line+1) + token.Pos(issue.Location().Position-offset), // The position of the first divergence.
 			Message: issue.Message(),
 		}
 
@@ -87,13 +99,6 @@ func runGoHeader(pass *analysis.Pass, conf *goheader.Configuration) error {
 				current += len(s)
 			}
 
-			commentLine := 1
-
-			// Inspired by https://github.com/denis-tingaikin/go-header/blob/4c75a6a2332f025705325d6c71fff4616aedf48f/analyzer.go#L85-L92
-			if len(file.Comments) > 0 && file.Comments[0].Pos() < file.Package {
-				commentLine = goanalysis.GetFilePositionFor(pass.Fset, file.Comments[0].Pos()).Line
-			}
-
 			start := f.LineStart(commentLine)
 
 			end := start + token.Pos(current)