reduce code duplication

src/borg/archive.py

@@ -777,7 +777,7 @@ Utilization of max. archive size: {csize_max:.0%}
         length = len(item.chunks)
         # the item should only have the *additional* chunks we processed after the last partial item:
         item.chunks = item.chunks[from_chunk:]
-        item.size = sum(chunk.size for chunk in item.chunks)
+        item.file_size(memorize=True)
         item.path += '.borg_part_%d' % number
         item.part = number
         number += 1
@@ -826,7 +826,7 @@ Utilization of max. archive size: {csize_max:.0%}
         )
         fd = sys.stdin.buffer  # binary
         self.chunk_file(item, cache, self.stats, backup_io_iter(self.chunker.chunkify(fd)))
-        item.size = sum(chunk.size for chunk in item.chunks)
+        item.file_size(memorize=True)
         self.stats.nfiles += 1
         self.add_item(item)
         return 'i'  # stdin
@@ -887,7 +887,7 @@ Utilization of max. archive size: {csize_max:.0%}
                 cache.memorize_file(path_hash, st, [c.id for c in item.chunks])
             status = status or 'M'  # regular file, modified (if not 'A' already)
         item.update(self.stat_attrs(st, path))
-        item.size = sum(chunk.size for chunk in item.chunks)
+        item.file_size(memorize=True)
         if is_special_file:
             # we processed a special file like a regular file. reflect that in mode,
             # so it can be extracted / accessed in FUSE mount like a regular file:

src/borg/archiver.py

@@ -605,9 +605,7 @@ class Archiver:
                 if consider_ids is not None:  # consider only specific chunks
                     size = sum(chunk.size for chunk in item.chunks if chunk.id in consider_ids)
                 else:  # consider all chunks
-                    size = item.get('size')
-                    if size is None:
-                        size = sum(chunk.size for chunk in item.chunks)
+                    size = item.file_size()
             return size
 
         def get_owner(item):

src/borg/helpers.py

@@ -1701,10 +1701,7 @@ class ItemFormatter(BaseFormatter):
         return len(item.get('chunks', []))
 
     def calculate_size(self, item):
-        size = item.get('size')
-        if size is not None:
-            return size
-        return sum(c.size for c in item.get('chunks', []))
+        return item.file_size()
 
     def calculate_csize(self, item):
         return sum(c.csize for c in item.get('chunks', []))

src/borg/item.pyx

@@ -172,16 +172,24 @@ class Item(PropDict):
 
     part = PropDict._make_property('part', int)
 
-    def file_size(self, hardlink_masters=None):
+    def file_size(self, hardlink_masters=None, memorize=False):
+        """determine the size of this item"""
         size = self.get('size')
         if size is not None:
             return size
-        hardlink_masters = hardlink_masters or {}
-        chunks, _ = hardlink_masters.get(self.get('source'), (None, None))
-        chunks = self.get('chunks', chunks)
-        if chunks is None:
-            return 0
-        return sum(chunk.size for chunk in chunks)
+        chunks = self.get('chunks')
+        having_chunks = chunks is not None
+        if not having_chunks:
+            # this item has no (own) chunks, but if this is a hardlink slave
+            # and we know the master, we can still compute the size.
+            hardlink_masters = hardlink_masters or {}
+            chunks, _ = hardlink_masters.get(self.get('source'), (None, None))
+            if chunks is None:
+                return 0
+        size = sum(chunk.size for chunk in chunks)
+        if memorize and having_chunks:
+            self.size = size
+        return size
 
 
 class EncryptedKey(PropDict):