Fix for bug where library names could collide

Multiple libraries from one file wouldn't use unique ID.name members.
Now used memory address instead of the name to keep track of which blocks we've visited.

bam/blend/blendfile_path_walker.py

@@ -267,7 +267,8 @@ class FilePath:
         if recursive and (level > 0) and (block_codes is not None) and (recursive_all is False):
             # prevent from expanding the
             # same datablock more then once
-            expand_codes = set()
+            # note: we could *almost* id_name, however this isn't unique for libraries.
+            expand_addr_visit = set()
             # {lib_id: {block_ids... }}
             expand_codes_idlib = {}
 
@@ -286,7 +287,7 @@ class FilePath:
                         expand_codes_idlib.setdefault(block[b'lib'], set()).add(block[b'name'])
                     return False
                 else:
-                    id_name = block[b'id.name']
+                    # id_name = block[b'id.name']
 
                     # if we touched this already, don't touch again
                     # FIXME, works in some cases but not others
@@ -295,9 +296,9 @@ class FilePath:
                         return False
                     '''
 
-                    len_prev = len(expand_codes)
-                    expand_codes.add(id_name)
-                    return (len_prev != len(expand_codes))
+                    len_prev = len(expand_addr_visit)
+                    expand_addr_visit.add(block.addr_old)
+                    return (len_prev != len(expand_addr_visit))
 
             def block_expand(block, code):
                 assert(block.code == code)
@@ -314,7 +315,7 @@ class FilePath:
                     if code == b'ID':
                         yield block
         else:
-            expand_codes = None
+            expand_addr_visit = None
 
             # set below
             expand_codes_idlib = None
@@ -384,10 +385,10 @@ class FilePath:
             for block in iter_blocks_id(code):
                 yield from FilePath.from_block(block, basedir, extra_info, level)
 
-        # print("A:", expand_codes)
+        # print("A:", expand_addr_visit)
         # print("B:", block_codes)
         if VERBOSE:
-            log_deps.info("%s%s" % (indent_str, set_as_str(expand_codes)))
+            log_deps.info("%s%s" % (indent_str, set_as_str(expand_addr_visit)))
 
         if recursive: