feat: Add function for backing up sources

Signed-off-by: Matej Focko <me@mfocko.xyz>

main.go

@@ -3,6 +3,7 @@ package main
 import (
 	"bufio"
 	"fmt"
+	"io"
 	"os"
 	"sort"
 
@@ -68,7 +69,18 @@ func printComments(wrapper *wrap.Wrapper, commentsByFile map[string]([]*gitea.Pu
 	}
 }
 
-func patchFiles(wrapper *wrap.Wrapper, commentsByFile map[string]([]*gitea.PullReviewComment)) {
+func BackUpSource(filepath string) {
+	inputFile, err := os.Open(filepath)
+	ExitOnError(err)
+	defer inputFile.Close()
+
+	BackUpSourceFile, err := os.Create(filepath + ".bck")
+	ExitOnError(err)
+	defer BackUpSourceFile.Close()
+
+	_, err = io.Copy(BackUpSourceFile, inputFile)
+	ExitOnError(err)
+}
 	for filepath, comments := range commentsByFile {
 		fmt.Printf("FILE: %s\n", filepath)