PICARD-2425: Handle possible exceptions with os.path.realpath

E.g. on Windows this can cause exceptions if drives are mounted without mount manager.

picard/file.py

@@ -78,6 +78,7 @@ from picard.util import (
     find_best_match,
     format_time,
     is_absolute_path,
+    normpath,
     thread,
     tracknum_and_title_from_filename,
 )
@@ -506,14 +507,10 @@ class File(QtCore.QObject, Item):
         if settings["move_files"]:
             new_dirname = settings["move_files_to"]
             if not is_absolute_path(new_dirname):
-                new_dirname = os.path.normpath(os.path.join(os.path.dirname(filename), new_dirname))
+                new_dirname = os.path.join(os.path.dirname(filename), new_dirname)
         else:
             new_dirname = os.path.dirname(filename)
-        try:
-            new_dirname = os.path.realpath(new_dirname)
-        except FileNotFoundError:
-            # os.path.realpath can fail if cwd does not exist and path is relative
-            pass
+        new_dirname = normpath(new_dirname)
         new_filename = os.path.basename(filename)
 
         if settings["rename_files"] or settings["move_files"]:

picard/ui/coverartbox.py

@@ -55,7 +55,10 @@ from picard.coverart.image import (
 )
 from picard.file import File
 from picard.track import Track
-from picard.util import imageinfo
+from picard.util import (
+    imageinfo,
+    normpath,
+)
 from picard.util.lrucache import LRUCache
 
 from picard.ui.item import FileListItem
@@ -411,7 +414,7 @@ class CoverArtBox(QtWidgets.QGroupBox):
                                        parse_response_type=None, queryargs=queryargs,
                                        priority=True, important=True)
         elif url.scheme() == 'file':
-            path = os.path.normpath(os.path.realpath(url.toLocalFile().rstrip("\0")))
+            path = normpath(url.toLocalFile().rstrip("\0"))
             if path and os.path.exists(path):
                 with open(path, 'rb') as f:
                     data = f.read()

picard/util/__init__.py

@@ -170,6 +170,8 @@ def normpath(path):
         path = os.path.realpath(path)
     except OSError as why:
         # realpath can fail if path does not exist or is not accessible
+        # or on Windows if drives are mounted without mount manager
+        # (see https://tickets.metabrainz.org/browse/PICARD-2425).
         log.warning('Failed getting realpath for "%s": %s', path, why)
     return os.path.normpath(path)
 

picard/util/filenaming.py

@@ -400,8 +400,15 @@ def samefile_different_casing(path1, path2):
     path2 = os.path.normpath(path2)
     if path1 == path2 or not os.path.exists(path1) or not os.path.exists(path2):
         return False
-    dir1 = os.path.realpath(os.path.normcase(os.path.dirname(path1)))
-    dir2 = os.path.realpath(os.path.normcase(os.path.dirname(path2)))
+    dir1 = os.path.normcase(os.path.dirname(path1))
+    dir2 = os.path.normcase(os.path.dirname(path2))
+    try:
+        dir1 = os.path.realpath(dir1)
+        dir2 = os.path.realpath(dir2)
+    except OSError:
+        # os.path.realpath can fail if cwd does not exist and path is relative
+        # or on Windows if drives are mounted without mount manager.
+        pass
     if dir1 != dir2 or not samefile(path1, path2):
         return False
     file1 = os.path.basename(path1)