cola/diffparse.py

   1 import os
   2 import re
   3
   4 from cola import utils
   5 from cola import gitcmds
   6
   7
   8 class DiffParser(object):
   9     """Handles parsing diff for use by the interactive index editor."""
  10     def __init__(self, model, filename='',
  11                  cached=True, branch=None, reverse=False):
  12
  13         self._header_re = re.compile('^@@ -(\d+),(\d+) \+(\d+),(\d+) @@.*')
  14         self._headers = []
  15
  16         self._idx = -1
  17         self._diffs = []
  18         self._diff_spans = []
  19         self._diff_offsets = []
  20
  21         self.start = None
  22         self.end = None
  23         self.offset = None
  24         self.diffs = []
  25         self.selected = []
  26
  27         (header, diff) = gitcmds.diff_helper(filename=filename,
  28                                              branch=branch,
  29                                              with_diff_header=True,
  30                                              cached=cached and not bool(branch),
  31                                              reverse=cached or bool(branch) or reverse)
  32         self.model = model
  33         self.diff = diff
  34         self.header = header
  35         self.parse_diff(diff)
  36
  37         # Always index into the non-reversed diff
  38         self.fwd_header, self.fwd_diff = \
  39             gitcmds.diff_helper(filename=filename,
  40                                 branch=branch,
  41                                 with_diff_header=True,
  42                                 cached=cached and not bool(branch),
  43                                 reverse=bool(branch))
  44
  45     def write_diff(self,filename,which,selected=False,noop=False):
  46         """Writes a new diff corresponding to the user's selection."""
  47         if not noop and which < len(self.diffs):
  48             diff = self.diffs[which]
  49             utils.write(filename, self.header + '\n' + diff + '\n')
  50             return True
  51         else:
  52             return False
  53
  54     def diffs(self):
  55         """Returns the list of diffs."""
  56         return self._diffs
  57
  58     def diff_subset(self, diff, start, end):
  59         """Processes the diffs and returns a selected subset from that diff.
  60         """
  61         adds = 0
  62         deletes = 0
  63         newdiff = []
  64         local_offset = 0
  65         offset = self._diff_spans[diff][0]
  66         diffguts = '\n'.join(self._diffs[diff])
  67
  68         for line in self._diffs[diff]:
  69             line_start = offset + local_offset
  70             local_offset += len(line) + 1 #\n
  71             line_end = offset + local_offset
  72             # |line1 |line2 |line3 |
  73             #   |--selection--|
  74             #   '-start       '-end
  75             # selection has head of diff (line3)
  76             if start < line_start and end > line_start and end < line_end:
  77                 newdiff.append(line)
  78                 if line.startswith('+'):
  79                     adds += 1
  80                 if line.startswith('-'):
  81                     deletes += 1
  82             # selection has all of diff (line2)
  83             elif start <= line_start and end >= line_end:
  84                 newdiff.append(line)
  85                 if line.startswith('+'):
  86                     adds += 1
  87                 if line.startswith('-'):
  88                     deletes += 1
  89             # selection has tail of diff (line1)
  90             elif start >= line_start and start < line_end - 1:
  91                 newdiff.append(line)
  92                 if line.startswith('+'):
  93                     adds += 1
  94                 if line.startswith('-'):
  95                     deletes += 1
  96             else:
  97                 # Don't add new lines unless selected
  98                 if line.startswith('+'):
  99                     continue
 100                 elif line.startswith('-'):
 101                     # Don't remove lines unless selected
 102                     newdiff.append(' ' + line[1:])
 103                 else:
 104                     newdiff.append(line)
 105
 106         new_count = self._headers[diff][1] + adds - deletes
 107         if new_count != self._headers[diff][3]:
 108             header = '@@ -%d,%d +%d,%d @@' % (
 109                             self._headers[diff][0],
 110                             self._headers[diff][1],
 111                             self._headers[diff][2],
 112                             new_count)
 113             newdiff[0] = header
 114
 115         return (self.header + '\n' + '\n'.join(newdiff) + '\n')
 116
 117     def spans(self):
 118         """Returns the line spans of each hunk."""
 119         return self._diff_spans
 120
 121     def offsets(self):
 122         """Returns the offsets."""
 123         return self._diff_offsets
 124
 125     def set_diff_to_offset(self, offset):
 126         """Sets the diff selection to be the hunk at a particular offset."""
 127         self.offset = offset
 128         self.diffs, self.selected = self.diff_for_offset(offset)
 129
 130     def set_diffs_to_range(self, start, end):
 131         """Sets the diff selection to be a range of hunks."""
 132         self.start = start
 133         self.end = end
 134         self.diffs, self.selected = self.diffs_for_range(start,end)
 135
 136     def diff_for_offset(self, offset):
 137         """Returns the hunks for a particular offset."""
 138         for idx, diff_offset in enumerate(self._diff_offsets):
 139             if offset < diff_offset:
 140                 return (['\n'.join(self._diffs[idx])], [idx])
 141         return ([],[])
 142
 143     def diffs_for_range(self, start, end):
 144         """Returns the hunks for a selected range."""
 145         diffs = []
 146         indices = []
 147         for idx, span in enumerate(self._diff_spans):
 148             has_end_of_diff = start >= span[0] and start < span[1]
 149             has_all_of_diff = start <= span[0] and end >= span[1]
 150             has_head_of_diff = end >= span[0] and end <= span[1]
 151
 152             selected_diff =(has_end_of_diff
 153                     or has_all_of_diff
 154                     or has_head_of_diff)
 155             if selected_diff:
 156                 diff = '\n'.join(self._diffs[idx])
 157                 diffs.append(diff)
 158                 indices.append(idx)
 159         return diffs, indices
 160
 161     def parse_diff(self, diff):
 162         """Parses a diff and extracts headers, offsets, hunks, etc.
 163         """
 164         total_offset = 0
 165         self._idx = -1
 166         self._headers = []
 167
 168         for idx, line in enumerate(diff.split('\n')):
 169             match = self._header_re.match(line)
 170             if match:
 171                 self._headers.append([
 172                         int(match.group(1)),
 173                         int(match.group(2)),
 174                         int(match.group(3)),
 175                         int(match.group(4))
 176                         ])
 177                 self._diffs.append( [line] )
 178
 179                 line_len = len(line) + 1 #\n
 180                 self._diff_spans.append([total_offset,
 181                         total_offset + line_len])
 182                 total_offset += line_len
 183                 self._diff_offsets.append(total_offset)
 184                 self._idx += 1
 185             else:
 186                 if self._idx < 0:
 187                     errmsg = 'Malformed diff?\n\n%s' % diff
 188                     raise AssertionError, errmsg
 189                 line_len = len(line) + 1
 190                 total_offset += line_len
 191
 192                 self._diffs[self._idx].append(line)
 193                 self._diff_spans[-1][-1] += line_len
 194                 self._diff_offsets[self._idx] += line_len
 195
 196     def process_diff_selection(self, selected, offset, selection,
 197                                apply_to_worktree=False):
 198         """Processes a diff selection and applies changes to git."""
 199         if selection:
 200             # qt destroys \r\n and makes it \n with no way of going back.
 201             # boo!  we work around that here.
 202             # I think this was win32-specific.  We might want to do
 203             # this on win32 only (TODO verify)
 204             if selection not in self.fwd_diff:
 205                 special_selection = selection.replace('\n', '\r\n')
 206                 if special_selection in self.fwd_diff:
 207                     selection = special_selection
 208                 else:
 209                     return
 210             start = self.fwd_diff.index(selection)
 211             end = start + len(selection)
 212             self.set_diffs_to_range(start, end)
 213         else:
 214             self.set_diff_to_offset(offset)
 215             selected = False
 216         # Process diff selection only
 217         if selected:
 218             for idx in self.selected:
 219                 contents = self.diff_subset(idx, start, end)
 220                 if contents:
 221                     tmpfile = self.model.tmp_filename()
 222                     utils.write(tmpfile, contents)
 223                     if apply_to_worktree:
 224                         self.model.apply_diff_to_worktree(tmpfile)
 225                     else:
 226                         self.model.apply_diff(tmpfile)
 227                     os.unlink(tmpfile)
 228         # Process a complete hunk
 229         else:
 230             for idx, diff in enumerate(self.diffs):
 231                 tmpfile = self.model.tmp_filename()
 232                 if self.write_diff(tmpfile,idx):
 233                     if apply_to_worktree:
 234                         self.model.apply_diff_to_worktree(tmpfile)
 235                     else:
 236                         self.model.apply_diff(tmpfile)
 237                     os.unlink(tmpfile)