cola/display.py

   1 """Display models and utility functions"""
   2 from __future__ import absolute_import, division, print_function, unicode_literals
   3 import collections
   4
   5
   6 def shorten_paths(source_paths):
   7     """Shorten a sequence of paths into unique strings for display"""
   8     result = {}
   9     # Start by assuming that all paths are in conflict.
  10     # On each iteration we will collect all the path suffixes, move the newly
  11     # unique entries to the result, and repeat until no conflicts remain.
  12     count = 0
  13     conflicts = list(source_paths)
  14     in_conflict = True
  15     while in_conflict:
  16         count += 1
  17         # Gather the suffixes for the current paths in conflict
  18         suffixes = collections.defaultdict(list)
  19         for path in conflicts:
  20             suffix = path_suffix(path, count)
  21             suffixes[suffix].append(path)
  22
  23         # Loop over the suffixes to gather new conflicts and unique entries.
  24         conflicts = []
  25         in_conflict = False
  26
  27         for suffix, paths in suffixes.items():
  28             # If only a single path exists for the suffix then no conflict
  29             # exists, and the suffix is valid.
  30             if len(paths) == 1:
  31                 result[paths[0]] = suffix
  32             # If this loop runs too long then bail out by using the full path.
  33             elif count >= 128:
  34                 for path in paths:
  35                     result[path] = path
  36             # If multiple paths map to the same suffix then the paths are
  37             # considered in conflict, and will be reprocessed.
  38             else:
  39                 conflicts.extend(paths)
  40                 in_conflict = True
  41
  42     return result
  43
  44
  45 def path_suffix(path, count):
  46     """Return `count` number of trailing path components"""
  47     path = normalize_path(path)
  48     components = path.split('/')[-count:]
  49     return '/'.join(components)
  50
  51
  52 def normalize_path(path):
  53     """Normalize a path so that only "/" is used as a separator"""
  54     return path.replace('\\', '/')