chiark - git - mdw - stgit/blob - stgit/lib/transaction.py

   1 from stgit import exception
   2 from stgit.out import *
   3 from stgit.lib import git
   4
   5 class TransactionException(exception.StgException):
   6     pass
   7
   8 class TransactionHalted(TransactionException):
   9     pass
  10
  11 def _print_current_patch(old_applied, new_applied):
  12     def now_at(pn):
  13         out.info('Now at patch "%s"' % pn)
  14     if not old_applied and not new_applied:
  15         pass
  16     elif not old_applied:
  17         now_at(new_applied[-1])
  18     elif not new_applied:
  19         out.info('No patch applied')
  20     elif old_applied[-1] == new_applied[-1]:
  21         pass
  22     else:
  23         now_at(new_applied[-1])
  24
  25 class _TransPatchMap(dict):
  26     def __init__(self, stack):
  27         dict.__init__(self)
  28         self.__stack = stack
  29     def __getitem__(self, pn):
  30         try:
  31             return dict.__getitem__(self, pn)
  32         except KeyError:
  33             return self.__stack.patches.get(pn).commit
  34
  35 class StackTransaction(object):
  36     def __init__(self, stack, msg):
  37         self.__stack = stack
  38         self.__msg = msg
  39         self.__patches = _TransPatchMap(stack)
  40         self.__applied = list(self.__stack.patchorder.applied)
  41         self.__unapplied = list(self.__stack.patchorder.unapplied)
  42         self.__error = None
  43         self.__current_tree = self.__stack.head.data.tree
  44     stack = property(lambda self: self.__stack)
  45     patches = property(lambda self: self.__patches)
  46     def __set_applied(self, val):
  47         self.__applied = list(val)
  48     applied = property(lambda self: self.__applied, __set_applied)
  49     def __set_unapplied(self, val):
  50         self.__unapplied = list(val)
  51     unapplied = property(lambda self: self.__unapplied, __set_unapplied)
  52     def __checkout(self, tree, iw):
  53         if not self.__stack.head_top_equal():
  54             out.error(
  55                 'HEAD and top are not the same.',
  56                 'This can happen if you modify a branch with git.',
  57                 '"stg repair --help" explains more about what to do next.')
  58             self.__abort()
  59         if self.__current_tree != tree:
  60             assert iw != None
  61             iw.checkout(self.__current_tree, tree)
  62             self.__current_tree = tree
  63     @staticmethod
  64     def __abort():
  65         raise TransactionException(
  66             'Command aborted (all changes rolled back)')
  67     def __check_consistency(self):
  68         remaining = set(self.__applied + self.__unapplied)
  69         for pn, commit in self.__patches.iteritems():
  70             if commit == None:
  71                 assert self.__stack.patches.exists(pn)
  72             else:
  73                 assert pn in remaining
  74     @property
  75     def __head(self):
  76         if self.__applied:
  77             return self.__patches[self.__applied[-1]]
  78         else:
  79             return self.__stack.base
  80     def abort(self, iw = None):
  81         # The only state we need to restore is index+worktree.
  82         if iw:
  83             self.__checkout(self.__stack.head.data.tree, iw)
  84     def run(self, iw = None):
  85         self.__check_consistency()
  86         new_head = self.__head
  87
  88         # Set branch head.
  89         try:
  90             self.__checkout(new_head.data.tree, iw)
  91         except git.CheckoutException:
  92             # We have to abort the transaction.
  93             self.abort(iw)
  94             self.__abort()
  95         self.__stack.set_head(new_head, self.__msg)
  96
  97         if self.__error:
  98             out.error(self.__error)
  99
 100         # Write patches.
 101         for pn, commit in self.__patches.iteritems():
 102             if self.__stack.patches.exists(pn):
 103                 p = self.__stack.patches.get(pn)
 104                 if commit == None:
 105                     p.delete()
 106                 else:
 107                     p.set_commit(commit, self.__msg)
 108             else:
 109                 self.__stack.patches.new(pn, commit, self.__msg)
 110         _print_current_patch(self.__stack.patchorder.applied, self.__applied)
 111         self.__stack.patchorder.applied = self.__applied
 112         self.__stack.patchorder.unapplied = self.__unapplied
 113
 114     def __halt(self, msg):
 115         self.__error = msg
 116         raise TransactionHalted(msg)
 117
 118     @staticmethod
 119     def __print_popped(popped):
 120         if len(popped) == 0:
 121             pass
 122         elif len(popped) == 1:
 123             out.info('Popped %s' % popped[0])
 124         else:
 125             out.info('Popped %s -- %s' % (popped[-1], popped[0]))
 126
 127     def pop_patches(self, p):
 128         """Pop all patches pn for which p(pn) is true. Return the list of
 129         other patches that had to be popped to accomplish this."""
 130         popped = []
 131         for i in xrange(len(self.applied)):
 132             if p(self.applied[i]):
 133                 popped = self.applied[i:]
 134                 del self.applied[i:]
 135                 break
 136         popped1 = [pn for pn in popped if not p(pn)]
 137         popped2 = [pn for pn in popped if p(pn)]
 138         self.unapplied = popped1 + popped2 + self.unapplied
 139         self.__print_popped(popped)
 140         return popped1
 141
 142     def delete_patches(self, p):
 143         """Delete all patches pn for which p(pn) is true. Return the list of
 144         other patches that had to be popped to accomplish this."""
 145         popped = []
 146         all_patches = self.applied + self.unapplied
 147         for i in xrange(len(self.applied)):
 148             if p(self.applied[i]):
 149                 popped = self.applied[i:]
 150                 del self.applied[i:]
 151                 break
 152         popped = [pn for pn in popped if not p(pn)]
 153         self.unapplied = popped + [pn for pn in self.unapplied if not p(pn)]
 154         self.__print_popped(popped)
 155         for pn in all_patches:
 156             if p(pn):
 157                 s = ['', ' (empty)'][self.patches[pn].data.is_nochange()]
 158                 self.patches[pn] = None
 159                 out.info('Deleted %s%s' % (pn, s))
 160         return popped
 161
 162     def push_patch(self, pn, iw = None):
 163         """Attempt to push the named patch. If this results in conflicts,
 164         halts the transaction. If index+worktree are given, spill any
 165         conflicts to them."""
 166         i = self.unapplied.index(pn)
 167         cd = self.patches[pn].data
 168         s = ['', ' (empty)'][cd.is_nochange()]
 169         oldparent = cd.parent
 170         cd = cd.set_parent(self.__head)
 171         base = oldparent.data.tree
 172         ours = cd.parent.data.tree
 173         theirs = cd.tree
 174         tree = self.__stack.repository.simple_merge(base, ours, theirs)
 175         merge_conflict = False
 176         if not tree:
 177             if iw == None:
 178                 self.__halt('%s does not apply cleanly' % pn)
 179             try:
 180                 self.__checkout(ours, iw)
 181             except git.CheckoutException:
 182                 self.__halt('Index/worktree dirty')
 183             try:
 184                 iw.merge(base, ours, theirs)
 185                 tree = iw.index.write_tree()
 186                 self.__current_tree = tree
 187                 s = ' (modified)'
 188             except git.MergeException:
 189                 tree = ours
 190                 merge_conflict = True
 191                 s = ' (conflict)'
 192         cd = cd.set_tree(tree)
 193         self.patches[pn] = self.__stack.repository.commit(cd)
 194         del self.unapplied[i]
 195         self.applied.append(pn)
 196         out.info('Pushed %s%s' % (pn, s))
 197         if merge_conflict:
 198             self.__halt('Merge conflict')