reorganise SaveBackup code a bit (#522)

src/SMAPI.Mods.SaveBackup/ModEntry.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Collections.Generic;
 using System.IO;
 using System.IO.Compression;
 using System.Linq;
@@ -27,16 +26,31 @@ namespace StardewModdingAPI.Mods.SaveBackup
         {
             try
             {
-                // read config
                 ModConfig config = this.Helper.ReadConfig<ModConfig>();
 
                 // init backup folder
-                DirectoryInfo folder = new DirectoryInfo(Path.Combine(this.Helper.DirectoryPath, "backups"));
+                DirectoryInfo backupFolder = new DirectoryInfo(Path.Combine(this.Helper.DirectoryPath, "backups"));
-                folder.Create();
+                backupFolder.Create();
 
                 // back up saves
+                this.CreateBackup(backupFolder);
+                this.PruneBackups(backupFolder, config.BackupsToKeep);
+            }
+            catch (Exception ex)
             {
-                    FileInfo file = new FileInfo(Path.Combine(folder.FullName, this.FileName));
+                this.Monitor.Log($"Error backing up saves: {ex}");
+            }
+        }
+
+
+        /*********
+        ** Private methods
+        *********/
+        /// <summary>Back up the current saves.</summary>
+        /// <param name="backupFolder">The folder containing save backups.</param>
+        private void CreateBackup(DirectoryInfo backupFolder)
+        {
+            FileInfo file = new FileInfo(Path.Combine(backupFolder.FullName, this.FileName));
             if (!file.Exists)
             {
                 this.Monitor.Log($"Adding {file.Name}...", LogLevel.Trace);
@@ -44,8 +58,17 @@ namespace StardewModdingAPI.Mods.SaveBackup
             }
         }
 
-                // prune old saves
+        /// <summary>Remove old backups if we've exceeded the limit.</summary>
-                foreach (FileInfo file in this.GetOldBackups(folder, config.BackupsToKeep))
+        /// <param name="backupFolder">The folder containing save backups.</param>
+        /// <param name="backupsToKeep">The number of backups to keep.</param>
+        private void PruneBackups(DirectoryInfo backupFolder, int backupsToKeep)
+        {
+            var oldBackups = backupFolder
+                .GetFiles()
+                .OrderByDescending(p => p.CreationTimeUtc)
+                .Skip(backupsToKeep);
+
+            foreach (FileInfo file in oldBackups)
             {
                 try
                 {
@@ -58,25 +81,5 @@ namespace StardewModdingAPI.Mods.SaveBackup
                 }
             }
         }
-            catch (Exception ex)
-            {
-                this.Monitor.Log($"Error backing up saves: {ex}");
-            }
-        }
-
-
-        /*********
-        ** Private methods
-        *********/
-        /// <summary>Get backups ordered by creation date.</summary>
-        /// <param name="folder">The folder to search.</param>
-        /// <param name="skip">The number of backups to skip.</param>
-        private IEnumerable<FileInfo> GetOldBackups(DirectoryInfo folder, int skip)
-        {
-            return folder
-                .GetFiles()
-                .OrderByDescending(p => p.CreationTimeUtc)
-                .Skip(skip);
-        }
     }
 }