No such backup/backup already esists

TODO.md

@@ -10,7 +10,6 @@
 * Lock the local repository to avoid index corruption
 
 ## Usability
-* Error: Backup already exists
 * Backup directories as a thing (list, remove)
 * Display backup name and path on backup integrity error
 * Better control over what is checked in `check` subcommand

src/cli/mod.rs

@@ -20,6 +20,7 @@ pub enum ErrorCode {
     InitializeLogger,
     CreateRepository,
     LoadRepository, SaveBackup, LoadBackup, LoadInode, LoadBundle,
+    NoSuchBackup, BackupAlreadyExists,
     AddKey, LoadKey, SaveKey,
     SaveConfig,
     LoadExcludes, InvalidExcludes,
@@ -58,7 +59,10 @@ impl ErrorCode {
             ErrorCode::DiffRun => 21,
             ErrorCode::VersionsRun => 22,
             ErrorCode::ImportRun => 23,
-            ErrorCode::FuseMount => 24
+            ErrorCode::FuseMount => 24,
+            //
+            ErrorCode::NoSuchBackup => 25,
+            ErrorCode::BackupAlreadyExists => 26
         }
     }
 }
@@ -92,6 +96,10 @@ fn open_repository(path: &str) -> Result<Repository, ErrorCode> {
 }
 
 fn get_backup(repo: &Repository, backup_name: &str) -> Result<Backup, ErrorCode> {
+    if !repo.has_backup(backup_name) {
+        error!("A backup with that name does not exist");
+        return Err(ErrorCode::NoSuchBackup)
+    }
     Ok(checked!(repo.get_backup(backup_name), "load backup", ErrorCode::LoadBackup))
 }
 
@@ -286,6 +294,10 @@ pub fn run() -> Result<(), ErrorCode> {
         },
         Arguments::Backup{repo_path, backup_name, src_path, full, reference, same_device, mut excludes, excludes_from, no_default_excludes, tar} => {
             let mut repo = try!(open_repository(&repo_path));
+            if repo.has_backup(&backup_name) {
+                error!("A backup with that name already exists");
+                return Err(ErrorCode::BackupAlreadyExists)
+            }
             let mut reference_backup = None;
             if !full && !tar {
                 reference_backup = match reference {

src/repository/backup.rs

@@ -41,6 +41,10 @@ impl Repository {
         Ok(try!(Backup::get_all_from(&self.crypto.lock().unwrap(), self.layout.backups_path())))
     }
 
+    pub fn has_backup(&self, name: &str) -> bool {
+        self.layout.backup_path(name).exists()
+    }
+
     pub fn get_backup(&self, name: &str) -> Result<Backup, RepositoryError> {
         Ok(try!(Backup::read_from(&self.crypto.lock().unwrap(), self.layout.backup_path(name))))
     }