Commit | Line | Data |
---|---|---|
652b2e67 KH |
1 | """The L{StackTransaction} class makes it possible to make complex |
2 | updates to an StGit stack in a safe and convenient way.""" | |
3 | ||
afa3f9b9 | 4 | import atexit |
1743e459 | 5 | import itertools as it |
afa3f9b9 | 6 | |
f9cc5e69 | 7 | from stgit import exception, utils |
352446d4 | 8 | from stgit.utils import any, all |
cbe4567e | 9 | from stgit.out import * |
117ed129 | 10 | from stgit.lib import git, log |
cbe4567e KH |
11 | |
12 | class TransactionException(exception.StgException): | |
652b2e67 KH |
13 | """Exception raised when something goes wrong with a |
14 | L{StackTransaction}.""" | |
cbe4567e | 15 | |
dcd32afa | 16 | class TransactionHalted(TransactionException): |
652b2e67 KH |
17 | """Exception raised when a L{StackTransaction} stops part-way through. |
18 | Used to make a non-local jump from the transaction setup to the | |
19 | part of the transaction code where the transaction is run.""" | |
dcd32afa KH |
20 | |
21 | def _print_current_patch(old_applied, new_applied): | |
cbe4567e KH |
22 | def now_at(pn): |
23 | out.info('Now at patch "%s"' % pn) | |
24 | if not old_applied and not new_applied: | |
25 | pass | |
26 | elif not old_applied: | |
27 | now_at(new_applied[-1]) | |
28 | elif not new_applied: | |
29 | out.info('No patch applied') | |
30 | elif old_applied[-1] == new_applied[-1]: | |
31 | pass | |
32 | else: | |
33 | now_at(new_applied[-1]) | |
34 | ||
dcd32afa | 35 | class _TransPatchMap(dict): |
652b2e67 | 36 | """Maps patch names to sha1 strings.""" |
dcd32afa KH |
37 | def __init__(self, stack): |
38 | dict.__init__(self) | |
39 | self.__stack = stack | |
40 | def __getitem__(self, pn): | |
41 | try: | |
42 | return dict.__getitem__(self, pn) | |
43 | except KeyError: | |
44 | return self.__stack.patches.get(pn).commit | |
45 | ||
cbe4567e | 46 | class StackTransaction(object): |
652b2e67 KH |
47 | """A stack transaction, used for making complex updates to an StGit |
48 | stack in one single operation that will either succeed or fail | |
49 | cleanly. | |
50 | ||
51 | The basic theory of operation is the following: | |
52 | ||
53 | 1. Create a transaction object. | |
54 | ||
55 | 2. Inside a:: | |
56 | ||
57 | try | |
58 | ... | |
59 | except TransactionHalted: | |
60 | pass | |
61 | ||
62 | block, update the transaction with e.g. methods like | |
63 | L{pop_patches} and L{push_patch}. This may create new git | |
64 | objects such as commits, but will not write any refs; this means | |
65 | that in case of a fatal error we can just walk away, no clean-up | |
66 | required. | |
67 | ||
68 | (Some operations may need to touch your index and working tree, | |
69 | though. But they are cleaned up when needed.) | |
70 | ||
71 | 3. After the C{try} block -- wheher or not the setup ran to | |
72 | completion or halted part-way through by raising a | |
73 | L{TransactionHalted} exception -- call the transaction's L{run} | |
74 | method. This will either succeed in writing the updated state to | |
75 | your refs and index+worktree, or fail without having done | |
76 | anything.""" | |
9690617a | 77 | def __init__(self, stack, msg, discard_changes = False, |
f4e6a60e | 78 | allow_conflicts = False, allow_bad_head = False): |
9690617a KH |
79 | """Create a new L{StackTransaction}. |
80 | ||
81 | @param discard_changes: Discard any changes in index+worktree | |
82 | @type discard_changes: bool | |
83 | @param allow_conflicts: Whether to allow pre-existing conflicts | |
84 | @type allow_conflicts: bool or function of L{StackTransaction}""" | |
cbe4567e KH |
85 | self.__stack = stack |
86 | self.__msg = msg | |
dcd32afa | 87 | self.__patches = _TransPatchMap(stack) |
cbe4567e KH |
88 | self.__applied = list(self.__stack.patchorder.applied) |
89 | self.__unapplied = list(self.__stack.patchorder.unapplied) | |
dcd2e3da | 90 | self.__hidden = list(self.__stack.patchorder.hidden) |
a3d7efcc | 91 | self.__conflicting_push = None |
dcd32afa KH |
92 | self.__error = None |
93 | self.__current_tree = self.__stack.head.data.tree | |
3b0552a7 | 94 | self.__base = self.__stack.base |
9690617a | 95 | self.__discard_changes = discard_changes |
c70033b4 | 96 | self.__bad_head = None |
781e549a KH |
97 | if isinstance(allow_conflicts, bool): |
98 | self.__allow_conflicts = lambda trans: allow_conflicts | |
99 | else: | |
100 | self.__allow_conflicts = allow_conflicts | |
afa3f9b9 | 101 | self.__temp_index = self.temp_index_tree = None |
f4e6a60e KH |
102 | if not allow_bad_head: |
103 | self.__assert_head_top_equal() | |
dcd32afa KH |
104 | stack = property(lambda self: self.__stack) |
105 | patches = property(lambda self: self.__patches) | |
cbe4567e KH |
106 | def __set_applied(self, val): |
107 | self.__applied = list(val) | |
108 | applied = property(lambda self: self.__applied, __set_applied) | |
109 | def __set_unapplied(self, val): | |
110 | self.__unapplied = list(val) | |
111 | unapplied = property(lambda self: self.__unapplied, __set_unapplied) | |
dcd2e3da KH |
112 | def __set_hidden(self, val): |
113 | self.__hidden = list(val) | |
114 | hidden = property(lambda self: self.__hidden, __set_hidden) | |
4ae6b67e KH |
115 | all_patches = property(lambda self: (self.__applied + self.__unapplied |
116 | + self.__hidden)) | |
3b0552a7 | 117 | def __set_base(self, val): |
980bde6a KH |
118 | assert (not self.__applied |
119 | or self.patches[self.applied[0]].data.parent == val) | |
3b0552a7 KH |
120 | self.__base = val |
121 | base = property(lambda self: self.__base, __set_base) | |
afa3f9b9 KH |
122 | @property |
123 | def temp_index(self): | |
124 | if not self.__temp_index: | |
125 | self.__temp_index = self.__stack.repository.temp_index() | |
126 | atexit.register(self.__temp_index.delete) | |
127 | return self.__temp_index | |
c70033b4 KH |
128 | @property |
129 | def top(self): | |
130 | if self.__applied: | |
131 | return self.__patches[self.__applied[-1]] | |
132 | else: | |
133 | return self.__base | |
134 | def __get_head(self): | |
135 | if self.__bad_head: | |
136 | return self.__bad_head | |
137 | else: | |
138 | return self.top | |
139 | def __set_head(self, val): | |
140 | self.__bad_head = val | |
141 | head = property(__get_head, __set_head) | |
f4e6a60e KH |
142 | def __assert_head_top_equal(self): |
143 | if not self.__stack.head_top_equal(): | |
dcd32afa KH |
144 | out.error( |
145 | 'HEAD and top are not the same.', | |
146 | 'This can happen if you modify a branch with git.', | |
147 | '"stg repair --help" explains more about what to do next.') | |
148 | self.__abort() | |
f4e6a60e KH |
149 | def __checkout(self, tree, iw, allow_bad_head): |
150 | if not allow_bad_head: | |
151 | self.__assert_head_top_equal() | |
9690617a | 152 | if self.__current_tree == tree and not self.__discard_changes: |
781e549a KH |
153 | # No tree change, but we still want to make sure that |
154 | # there are no unresolved conflicts. Conflicts | |
155 | # conceptually "belong" to the topmost patch, and just | |
156 | # carrying them along to another patch is confusing. | |
157 | if (self.__allow_conflicts(self) or iw == None | |
158 | or not iw.index.conflicts()): | |
159 | return | |
160 | out.error('Need to resolve conflicts first') | |
161 | self.__abort() | |
162 | assert iw != None | |
9690617a KH |
163 | if self.__discard_changes: |
164 | iw.checkout_hard(tree) | |
165 | else: | |
166 | iw.checkout(self.__current_tree, tree) | |
781e549a | 167 | self.__current_tree = tree |
dcd32afa KH |
168 | @staticmethod |
169 | def __abort(): | |
170 | raise TransactionException( | |
171 | 'Command aborted (all changes rolled back)') | |
cbe4567e | 172 | def __check_consistency(self): |
4ae6b67e | 173 | remaining = set(self.all_patches) |
cbe4567e KH |
174 | for pn, commit in self.__patches.iteritems(): |
175 | if commit == None: | |
176 | assert self.__stack.patches.exists(pn) | |
177 | else: | |
178 | assert pn in remaining | |
59032ccd KH |
179 | def abort(self, iw = None): |
180 | # The only state we need to restore is index+worktree. | |
181 | if iw: | |
c70033b4 KH |
182 | self.__checkout(self.__stack.head.data.tree, iw, |
183 | allow_bad_head = True) | |
85aaed81 KH |
184 | def run(self, iw = None, set_head = True, allow_bad_head = False, |
185 | print_current_patch = True): | |
652b2e67 KH |
186 | """Execute the transaction. Will either succeed, or fail (with an |
187 | exception) and do nothing.""" | |
dcd32afa | 188 | self.__check_consistency() |
c70033b4 KH |
189 | log.log_external_mods(self.__stack) |
190 | new_head = self.head | |
cbe4567e KH |
191 | |
192 | # Set branch head. | |
bca31c2f KH |
193 | if set_head: |
194 | if iw: | |
195 | try: | |
c70033b4 | 196 | self.__checkout(new_head.data.tree, iw, allow_bad_head) |
bca31c2f KH |
197 | except git.CheckoutException: |
198 | # We have to abort the transaction. | |
199 | self.abort(iw) | |
200 | self.__abort() | |
201 | self.__stack.set_head(new_head, self.__msg) | |
cbe4567e | 202 | |
dcd32afa KH |
203 | if self.__error: |
204 | out.error(self.__error) | |
205 | ||
cbe4567e | 206 | # Write patches. |
a3d7efcc KH |
207 | def write(msg): |
208 | for pn, commit in self.__patches.iteritems(): | |
209 | if self.__stack.patches.exists(pn): | |
210 | p = self.__stack.patches.get(pn) | |
211 | if commit == None: | |
212 | p.delete() | |
213 | else: | |
214 | p.set_commit(commit, msg) | |
cbe4567e | 215 | else: |
a3d7efcc KH |
216 | self.__stack.patches.new(pn, commit, msg) |
217 | self.__stack.patchorder.applied = self.__applied | |
218 | self.__stack.patchorder.unapplied = self.__unapplied | |
219 | self.__stack.patchorder.hidden = self.__hidden | |
220 | log.log_entry(self.__stack, msg) | |
221 | old_applied = self.__stack.patchorder.applied | |
222 | write(self.__msg) | |
223 | if self.__conflicting_push != None: | |
224 | self.__patches = _TransPatchMap(self.__stack) | |
225 | self.__conflicting_push() | |
226 | write(self.__msg + ' (CONFLICT)') | |
85aaed81 KH |
227 | if print_current_patch: |
228 | _print_current_patch(old_applied, self.__applied) | |
dcd32afa | 229 | |
f9cc5e69 KH |
230 | if self.__error: |
231 | return utils.STGIT_CONFLICT | |
232 | else: | |
233 | return utils.STGIT_SUCCESS | |
234 | ||
dcd32afa KH |
235 | def __halt(self, msg): |
236 | self.__error = msg | |
237 | raise TransactionHalted(msg) | |
238 | ||
239 | @staticmethod | |
240 | def __print_popped(popped): | |
241 | if len(popped) == 0: | |
242 | pass | |
243 | elif len(popped) == 1: | |
244 | out.info('Popped %s' % popped[0]) | |
245 | else: | |
246 | out.info('Popped %s -- %s' % (popped[-1], popped[0])) | |
247 | ||
248 | def pop_patches(self, p): | |
249 | """Pop all patches pn for which p(pn) is true. Return the list of | |
652b2e67 KH |
250 | other patches that had to be popped to accomplish this. Always |
251 | succeeds.""" | |
dcd32afa KH |
252 | popped = [] |
253 | for i in xrange(len(self.applied)): | |
254 | if p(self.applied[i]): | |
255 | popped = self.applied[i:] | |
256 | del self.applied[i:] | |
257 | break | |
258 | popped1 = [pn for pn in popped if not p(pn)] | |
259 | popped2 = [pn for pn in popped if p(pn)] | |
260 | self.unapplied = popped1 + popped2 + self.unapplied | |
261 | self.__print_popped(popped) | |
262 | return popped1 | |
263 | ||
85aaed81 | 264 | def delete_patches(self, p, quiet = False): |
dcd32afa | 265 | """Delete all patches pn for which p(pn) is true. Return the list of |
652b2e67 KH |
266 | other patches that had to be popped to accomplish this. Always |
267 | succeeds.""" | |
dcd32afa | 268 | popped = [] |
dcd2e3da | 269 | all_patches = self.applied + self.unapplied + self.hidden |
dcd32afa KH |
270 | for i in xrange(len(self.applied)): |
271 | if p(self.applied[i]): | |
272 | popped = self.applied[i:] | |
273 | del self.applied[i:] | |
274 | break | |
275 | popped = [pn for pn in popped if not p(pn)] | |
276 | self.unapplied = popped + [pn for pn in self.unapplied if not p(pn)] | |
dcd2e3da | 277 | self.hidden = [pn for pn in self.hidden if not p(pn)] |
dcd32afa KH |
278 | self.__print_popped(popped) |
279 | for pn in all_patches: | |
280 | if p(pn): | |
281 | s = ['', ' (empty)'][self.patches[pn].data.is_nochange()] | |
282 | self.patches[pn] = None | |
85aaed81 KH |
283 | if not quiet: |
284 | out.info('Deleted %s%s' % (pn, s)) | |
dcd32afa KH |
285 | return popped |
286 | ||
287 | def push_patch(self, pn, iw = None): | |
288 | """Attempt to push the named patch. If this results in conflicts, | |
289 | halts the transaction. If index+worktree are given, spill any | |
290 | conflicts to them.""" | |
352446d4 KH |
291 | orig_cd = self.patches[pn].data |
292 | cd = orig_cd.set_committer(None) | |
dcd32afa KH |
293 | s = ['', ' (empty)'][cd.is_nochange()] |
294 | oldparent = cd.parent | |
c70033b4 | 295 | cd = cd.set_parent(self.top) |
dcd32afa KH |
296 | base = oldparent.data.tree |
297 | ours = cd.parent.data.tree | |
298 | theirs = cd.tree | |
afa3f9b9 KH |
299 | tree, self.temp_index_tree = self.temp_index.merge( |
300 | base, ours, theirs, self.temp_index_tree) | |
dcd32afa KH |
301 | merge_conflict = False |
302 | if not tree: | |
303 | if iw == None: | |
304 | self.__halt('%s does not apply cleanly' % pn) | |
305 | try: | |
c70033b4 | 306 | self.__checkout(ours, iw, allow_bad_head = False) |
dcd32afa KH |
307 | except git.CheckoutException: |
308 | self.__halt('Index/worktree dirty') | |
309 | try: | |
310 | iw.merge(base, ours, theirs) | |
311 | tree = iw.index.write_tree() | |
312 | self.__current_tree = tree | |
313 | s = ' (modified)' | |
363d432f | 314 | except git.MergeConflictException: |
dcd32afa KH |
315 | tree = ours |
316 | merge_conflict = True | |
317 | s = ' (conflict)' | |
363d432f KH |
318 | except git.MergeException, e: |
319 | self.__halt(str(e)) | |
dcd32afa | 320 | cd = cd.set_tree(tree) |
352446d4 KH |
321 | if any(getattr(cd, a) != getattr(orig_cd, a) for a in |
322 | ['parent', 'tree', 'author', 'message']): | |
a3d7efcc | 323 | comm = self.__stack.repository.commit(cd) |
352446d4 | 324 | else: |
a3d7efcc | 325 | comm = None |
352446d4 | 326 | s = ' (unmodified)' |
dcd32afa | 327 | out.info('Pushed %s%s' % (pn, s)) |
a3d7efcc KH |
328 | def update(): |
329 | if comm: | |
330 | self.patches[pn] = comm | |
331 | if pn in self.hidden: | |
332 | x = self.hidden | |
333 | else: | |
334 | x = self.unapplied | |
335 | del x[x.index(pn)] | |
336 | self.applied.append(pn) | |
dcd32afa | 337 | if merge_conflict: |
781e549a KH |
338 | # We've just caused conflicts, so we must allow them in |
339 | # the final checkout. | |
340 | self.__allow_conflicts = lambda trans: True | |
341 | ||
a3d7efcc KH |
342 | # Save this update so that we can run it a little later. |
343 | self.__conflicting_push = update | |
dcd32afa | 344 | self.__halt('Merge conflict') |
a3d7efcc KH |
345 | else: |
346 | # Update immediately. | |
347 | update() | |
1743e459 KH |
348 | |
349 | def reorder_patches(self, applied, unapplied, hidden, iw = None): | |
350 | """Push and pop patches to attain the given ordering.""" | |
351 | common = len(list(it.takewhile(lambda (a, b): a == b, | |
352 | zip(self.applied, applied)))) | |
353 | to_pop = set(self.applied[common:]) | |
354 | self.pop_patches(lambda pn: pn in to_pop) | |
355 | for pn in applied[common:]: | |
356 | self.push_patch(pn, iw) | |
357 | assert self.applied == applied | |
358 | assert set(self.unapplied + self.hidden) == set(unapplied + hidden) | |
359 | self.unapplied = unapplied | |
360 | self.hidden = hidden |