conditional deletes in some cases (suggested in #170)

NEWS

@@ -23,6 +23,7 @@
   to the @listen decorator (Thanks again, Lugoues!)
 * In path formats, $albumartist now falls back to $artist (as well as
   the other way around).
+* Fix some crashes when deleting files that don't exist.
 * Fix adding individual tracks in BPD.
 
 1.0b7

beets/library.py

@@ -910,7 +910,7 @@ class Library(BaseLibrary):
                 album.remove(delete, False)
 
         if delete:
-            os.unlink(syspath(item.path))
+            util.soft_remove(item.path)
             util.prune_dirs(os.path.dirname(item.path), self.directory)
 
 
@@ -1111,7 +1111,7 @@ class Album(BaseAlbum):
             # Delete art file.
             artpath = self.artpath
             if artpath:
-                os.unlink(syspath(artpath))
+                util.soft_remove(artpath)
         
         # Remove album from database.
         self._library.conn.execute(
@@ -1170,7 +1170,7 @@ class Album(BaseAlbum):
         oldart = self.artpath
         artdest = self.art_destination(path)
         if oldart == artdest:
-            os.unlink(syspath(oldart))
+            os.soft_remove(oldart)
         
         shutil.copyfile(syspath(path), syspath(artdest))
         self.artpath = artdest

beets/util/__init__.py

@@ -167,6 +167,12 @@ def syspath(path, pathmod=None):
 
     return path
 
+def soft_remove(path):
+    """Remove the file if it exists."""
+    path = syspath(path)
+    if os.path.exists(path):
+        os.remove(path)
+
 # Note: POSIX actually supports \ and : -- I just think they're
 # a pain. And ? has caused problems for some.
 CHAR_REPLACE = [

test/test_files.py

@@ -287,6 +287,25 @@ class RemoveTest(unittest.TestCase):
         self.lib.remove(self.i, True)
         self.assertTrue(os.path.exists(parent))
 
+# Tests that we can "delete" nonexistent files.
+class SoftRemoveTest(unittest.TestCase, _common.ExtraAsserts):
+    def setUp(self):
+        self.path = os.path.join(_common.RSRC, 'testfile')
+        touch(self.path)
+    def tearDown(self):
+        if os.path.exists(self.path):
+            os.remove(self.path)
+
+    def test_soft_remove_deletes_file(self):
+        util.soft_remove(self.path)
+        self.assertNotExists(self.path)
+
+    def test_soft_remove_silent_on_no_file(self):
+        try:
+            util.soft_remove(self.path + 'XXX')
+        except OSError:
+            self.fail('OSError when removing path')
+
 def suite():
     return unittest.TestLoader().loadTestsFromName(__name__)