File size: 62,060 Bytes
66b3b8e | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 | from __future__ import annotations
import collections
import re
from typing import Any
from typing import Callable
from typing import cast
from typing import Collection
from typing import Deque
from typing import Dict
from typing import FrozenSet
from typing import Iterable
from typing import Iterator
from typing import List
from typing import Optional
from typing import overload
from typing import Protocol
from typing import Sequence
from typing import Set
from typing import Tuple
from typing import TYPE_CHECKING
from typing import TypeVar
from typing import Union
from sqlalchemy import util as sqlautil
from .. import util
from ..util import not_none
if TYPE_CHECKING:
from typing import Literal
_RevIdType = Union[str, List[str], Tuple[str, ...]]
_GetRevArg = Union[
str,
Iterable[Optional[str]],
Iterable[str],
]
_RevisionIdentifierType = Union[str, Tuple[str, ...], None]
_RevisionOrStr = Union["Revision", str]
_RevisionOrBase = Union["Revision", "Literal['base']"]
_InterimRevisionMapType = Dict[str, "Revision"]
_RevisionMapType = Dict[Union[None, str, Tuple[()]], Optional["Revision"]]
_T = TypeVar("_T")
_TR = TypeVar("_TR", bound=Optional[_RevisionOrStr])
_relative_destination = re.compile(r"(?:(.+?)@)?(\w+)?((?:\+|-)\d+)")
_revision_illegal_chars = ["@", "-", "+"]
class _CollectRevisionsProtocol(Protocol):
def __call__(
self,
upper: _RevisionIdentifierType,
lower: _RevisionIdentifierType,
inclusive: bool,
implicit_base: bool,
assert_relative_length: bool,
) -> Tuple[Set[Revision], Tuple[Optional[_RevisionOrBase], ...]]:
...
class RevisionError(Exception):
pass
class RangeNotAncestorError(RevisionError):
def __init__(
self, lower: _RevisionIdentifierType, upper: _RevisionIdentifierType
) -> None:
self.lower = lower
self.upper = upper
super().__init__(
"Revision %s is not an ancestor of revision %s"
% (lower or "base", upper or "base")
)
class MultipleHeads(RevisionError):
def __init__(self, heads: Sequence[str], argument: Optional[str]) -> None:
self.heads = heads
self.argument = argument
super().__init__(
"Multiple heads are present for given argument '%s'; "
"%s" % (argument, ", ".join(heads))
)
class ResolutionError(RevisionError):
def __init__(self, message: str, argument: str) -> None:
super().__init__(message)
self.argument = argument
class CycleDetected(RevisionError):
kind = "Cycle"
def __init__(self, revisions: Sequence[str]) -> None:
self.revisions = revisions
super().__init__(
"%s is detected in revisions (%s)"
% (self.kind, ", ".join(revisions))
)
class DependencyCycleDetected(CycleDetected):
kind = "Dependency cycle"
def __init__(self, revisions: Sequence[str]) -> None:
super().__init__(revisions)
class LoopDetected(CycleDetected):
kind = "Self-loop"
def __init__(self, revision: str) -> None:
super().__init__([revision])
class DependencyLoopDetected(DependencyCycleDetected, LoopDetected):
kind = "Dependency self-loop"
def __init__(self, revision: Sequence[str]) -> None:
super().__init__(revision)
class RevisionMap:
"""Maintains a map of :class:`.Revision` objects.
:class:`.RevisionMap` is used by :class:`.ScriptDirectory` to maintain
and traverse the collection of :class:`.Script` objects, which are
themselves instances of :class:`.Revision`.
"""
def __init__(self, generator: Callable[[], Iterable[Revision]]) -> None:
"""Construct a new :class:`.RevisionMap`.
:param generator: a zero-arg callable that will generate an iterable
of :class:`.Revision` instances to be used. These are typically
:class:`.Script` subclasses within regular Alembic use.
"""
self._generator = generator
@util.memoized_property
def heads(self) -> Tuple[str, ...]:
"""All "head" revisions as strings.
This is normally a tuple of length one,
unless unmerged branches are present.
:return: a tuple of string revision numbers.
"""
self._revision_map
return self.heads
@util.memoized_property
def bases(self) -> Tuple[str, ...]:
"""All "base" revisions as strings.
These are revisions that have a ``down_revision`` of None,
or empty tuple.
:return: a tuple of string revision numbers.
"""
self._revision_map
return self.bases
@util.memoized_property
def _real_heads(self) -> Tuple[str, ...]:
"""All "real" head revisions as strings.
:return: a tuple of string revision numbers.
"""
self._revision_map
return self._real_heads
@util.memoized_property
def _real_bases(self) -> Tuple[str, ...]:
"""All "real" base revisions as strings.
:return: a tuple of string revision numbers.
"""
self._revision_map
return self._real_bases
@util.memoized_property
def _revision_map(self) -> _RevisionMapType:
"""memoized attribute, initializes the revision map from the
initial collection.
"""
# Ordering required for some tests to pass (but not required in
# general)
map_: _InterimRevisionMapType = sqlautil.OrderedDict()
heads: Set[Revision] = sqlautil.OrderedSet()
_real_heads: Set[Revision] = sqlautil.OrderedSet()
bases: Tuple[Revision, ...] = ()
_real_bases: Tuple[Revision, ...] = ()
has_branch_labels = set()
all_revisions = set()
for revision in self._generator():
all_revisions.add(revision)
if revision.revision in map_:
util.warn(
"Revision %s is present more than once" % revision.revision
)
map_[revision.revision] = revision
if revision.branch_labels:
has_branch_labels.add(revision)
heads.add(revision)
_real_heads.add(revision)
if revision.is_base:
bases += (revision,)
if revision._is_real_base:
_real_bases += (revision,)
# add the branch_labels to the map_. We'll need these
# to resolve the dependencies.
rev_map = map_.copy()
self._map_branch_labels(
has_branch_labels, cast(_RevisionMapType, map_)
)
# resolve dependency names from branch labels and symbolic
# names
self._add_depends_on(all_revisions, cast(_RevisionMapType, map_))
for rev in map_.values():
for downrev in rev._all_down_revisions:
if downrev not in map_:
util.warn(
"Revision %s referenced from %s is not present"
% (downrev, rev)
)
down_revision = map_[downrev]
down_revision.add_nextrev(rev)
if downrev in rev._versioned_down_revisions:
heads.discard(down_revision)
_real_heads.discard(down_revision)
# once the map has downrevisions populated, the dependencies
# can be further refined to include only those which are not
# already ancestors
self._normalize_depends_on(all_revisions, cast(_RevisionMapType, map_))
self._detect_cycles(rev_map, heads, bases, _real_heads, _real_bases)
revision_map: _RevisionMapType = dict(map_.items())
revision_map[None] = revision_map[()] = None
self.heads = tuple(rev.revision for rev in heads)
self._real_heads = tuple(rev.revision for rev in _real_heads)
self.bases = tuple(rev.revision for rev in bases)
self._real_bases = tuple(rev.revision for rev in _real_bases)
self._add_branches(has_branch_labels, revision_map)
return revision_map
def _detect_cycles(
self,
rev_map: _InterimRevisionMapType,
heads: Set[Revision],
bases: Tuple[Revision, ...],
_real_heads: Set[Revision],
_real_bases: Tuple[Revision, ...],
) -> None:
if not rev_map:
return
if not heads or not bases:
raise CycleDetected(list(rev_map))
total_space = {
rev.revision
for rev in self._iterate_related_revisions(
lambda r: r._versioned_down_revisions,
heads,
map_=cast(_RevisionMapType, rev_map),
)
}.intersection(
rev.revision
for rev in self._iterate_related_revisions(
lambda r: r.nextrev,
bases,
map_=cast(_RevisionMapType, rev_map),
)
)
deleted_revs = set(rev_map.keys()) - total_space
if deleted_revs:
raise CycleDetected(sorted(deleted_revs))
if not _real_heads or not _real_bases:
raise DependencyCycleDetected(list(rev_map))
total_space = {
rev.revision
for rev in self._iterate_related_revisions(
lambda r: r._all_down_revisions,
_real_heads,
map_=cast(_RevisionMapType, rev_map),
)
}.intersection(
rev.revision
for rev in self._iterate_related_revisions(
lambda r: r._all_nextrev,
_real_bases,
map_=cast(_RevisionMapType, rev_map),
)
)
deleted_revs = set(rev_map.keys()) - total_space
if deleted_revs:
raise DependencyCycleDetected(sorted(deleted_revs))
def _map_branch_labels(
self, revisions: Collection[Revision], map_: _RevisionMapType
) -> None:
for revision in revisions:
if revision.branch_labels:
assert revision._orig_branch_labels is not None
for branch_label in revision._orig_branch_labels:
if branch_label in map_:
map_rev = map_[branch_label]
assert map_rev is not None
raise RevisionError(
"Branch name '%s' in revision %s already "
"used by revision %s"
% (
branch_label,
revision.revision,
map_rev.revision,
)
)
map_[branch_label] = revision
def _add_branches(
self, revisions: Collection[Revision], map_: _RevisionMapType
) -> None:
for revision in revisions:
if revision.branch_labels:
revision.branch_labels.update(revision.branch_labels)
for node in self._get_descendant_nodes(
[revision], map_, include_dependencies=False
):
node.branch_labels.update(revision.branch_labels)
parent = node
while (
parent
and not parent._is_real_branch_point
and not parent.is_merge_point
):
parent.branch_labels.update(revision.branch_labels)
if parent.down_revision:
parent = map_[parent.down_revision]
else:
break
def _add_depends_on(
self, revisions: Collection[Revision], map_: _RevisionMapType
) -> None:
"""Resolve the 'dependencies' for each revision in a collection
in terms of actual revision ids, as opposed to branch labels or other
symbolic names.
The collection is then assigned to the _resolved_dependencies
attribute on each revision object.
"""
for revision in revisions:
if revision.dependencies:
deps = [
map_[dep] for dep in util.to_tuple(revision.dependencies)
]
revision._resolved_dependencies = tuple(
[d.revision for d in deps if d is not None]
)
else:
revision._resolved_dependencies = ()
def _normalize_depends_on(
self, revisions: Collection[Revision], map_: _RevisionMapType
) -> None:
"""Create a collection of "dependencies" that omits dependencies
that are already ancestor nodes for each revision in a given
collection.
This builds upon the _resolved_dependencies collection created in the
_add_depends_on() method, looking in the fully populated revision map
for ancestors, and omitting them as the _resolved_dependencies
collection as it is copied to a new collection. The new collection is
then assigned to the _normalized_resolved_dependencies attribute on
each revision object.
The collection is then used to determine the immediate "down revision"
identifiers for this revision.
"""
for revision in revisions:
if revision._resolved_dependencies:
normalized_resolved = set(revision._resolved_dependencies)
for rev in self._get_ancestor_nodes(
[revision],
include_dependencies=False,
map_=map_,
):
if rev is revision:
continue
elif rev._resolved_dependencies:
normalized_resolved.difference_update(
rev._resolved_dependencies
)
revision._normalized_resolved_dependencies = tuple(
normalized_resolved
)
else:
revision._normalized_resolved_dependencies = ()
def add_revision(self, revision: Revision, _replace: bool = False) -> None:
"""add a single revision to an existing map.
This method is for single-revision use cases, it's not
appropriate for fully populating an entire revision map.
"""
map_ = self._revision_map
if not _replace and revision.revision in map_:
util.warn(
"Revision %s is present more than once" % revision.revision
)
elif _replace and revision.revision not in map_:
raise Exception("revision %s not in map" % revision.revision)
map_[revision.revision] = revision
revisions = [revision]
self._add_branches(revisions, map_)
self._map_branch_labels(revisions, map_)
self._add_depends_on(revisions, map_)
if revision.is_base:
self.bases += (revision.revision,)
if revision._is_real_base:
self._real_bases += (revision.revision,)
for downrev in revision._all_down_revisions:
if downrev not in map_:
util.warn(
"Revision %s referenced from %s is not present"
% (downrev, revision)
)
not_none(map_[downrev]).add_nextrev(revision)
self._normalize_depends_on(revisions, map_)
if revision._is_real_head:
self._real_heads = tuple(
head
for head in self._real_heads
if head
not in set(revision._all_down_revisions).union(
[revision.revision]
)
) + (revision.revision,)
if revision.is_head:
self.heads = tuple(
head
for head in self.heads
if head
not in set(revision._versioned_down_revisions).union(
[revision.revision]
)
) + (revision.revision,)
def get_current_head(
self, branch_label: Optional[str] = None
) -> Optional[str]:
"""Return the current head revision.
If the script directory has multiple heads
due to branching, an error is raised;
:meth:`.ScriptDirectory.get_heads` should be
preferred.
:param branch_label: optional branch name which will limit the
heads considered to those which include that branch_label.
:return: a string revision number.
.. seealso::
:meth:`.ScriptDirectory.get_heads`
"""
current_heads: Sequence[str] = self.heads
if branch_label:
current_heads = self.filter_for_lineage(
current_heads, branch_label
)
if len(current_heads) > 1:
raise MultipleHeads(
current_heads,
"%s@head" % branch_label if branch_label else "head",
)
if current_heads:
return current_heads[0]
else:
return None
def _get_base_revisions(self, identifier: str) -> Tuple[str, ...]:
return self.filter_for_lineage(self.bases, identifier)
def get_revisions(
self, id_: Optional[_GetRevArg]
) -> Tuple[Optional[_RevisionOrBase], ...]:
"""Return the :class:`.Revision` instances with the given rev id
or identifiers.
May be given a single identifier, a sequence of identifiers, or the
special symbols "head" or "base". The result is a tuple of one
or more identifiers, or an empty tuple in the case of "base".
In the cases where 'head', 'heads' is requested and the
revision map is empty, returns an empty tuple.
Supports partial identifiers, where the given identifier
is matched against all identifiers that start with the given
characters; if there is exactly one match, that determines the
full revision.
"""
if isinstance(id_, (list, tuple, set, frozenset)):
return sum([self.get_revisions(id_elem) for id_elem in id_], ())
else:
resolved_id, branch_label = self._resolve_revision_number(id_)
if len(resolved_id) == 1:
try:
rint = int(resolved_id[0])
if rint < 0:
# branch@-n -> walk down from heads
select_heads = self.get_revisions("heads")
if branch_label is not None:
select_heads = tuple(
head
for head in select_heads
if branch_label
in is_revision(head).branch_labels
)
return tuple(
self._walk(head, steps=rint)
for head in select_heads
)
except ValueError:
# couldn't resolve as integer
pass
return tuple(
self._revision_for_ident(rev_id, branch_label)
for rev_id in resolved_id
)
def get_revision(self, id_: Optional[str]) -> Optional[Revision]:
"""Return the :class:`.Revision` instance with the given rev id.
If a symbolic name such as "head" or "base" is given, resolves
the identifier into the current head or base revision. If the symbolic
name refers to multiples, :class:`.MultipleHeads` is raised.
Supports partial identifiers, where the given identifier
is matched against all identifiers that start with the given
characters; if there is exactly one match, that determines the
full revision.
"""
resolved_id, branch_label = self._resolve_revision_number(id_)
if len(resolved_id) > 1:
raise MultipleHeads(resolved_id, id_)
resolved: Union[str, Tuple[()]] = resolved_id[0] if resolved_id else ()
return self._revision_for_ident(resolved, branch_label)
def _resolve_branch(self, branch_label: str) -> Optional[Revision]:
try:
branch_rev = self._revision_map[branch_label]
except KeyError:
try:
nonbranch_rev = self._revision_for_ident(branch_label)
except ResolutionError as re:
raise ResolutionError(
"No such branch: '%s'" % branch_label, branch_label
) from re
else:
return nonbranch_rev
else:
return branch_rev
def _revision_for_ident(
self,
resolved_id: Union[str, Tuple[()], None],
check_branch: Optional[str] = None,
) -> Optional[Revision]:
branch_rev: Optional[Revision]
if check_branch:
branch_rev = self._resolve_branch(check_branch)
else:
branch_rev = None
revision: Union[Optional[Revision], Literal[False]]
try:
revision = self._revision_map[resolved_id]
except KeyError:
# break out to avoid misleading py3k stack traces
revision = False
revs: Sequence[str]
if revision is False:
assert resolved_id
# do a partial lookup
revs = [
x
for x in self._revision_map
if x and len(x) > 3 and x.startswith(resolved_id)
]
if branch_rev:
revs = self.filter_for_lineage(revs, check_branch)
if not revs:
raise ResolutionError(
"No such revision or branch '%s'%s"
% (
resolved_id,
(
"; please ensure at least four characters are "
"present for partial revision identifier matches"
if len(resolved_id) < 4
else ""
),
),
resolved_id,
)
elif len(revs) > 1:
raise ResolutionError(
"Multiple revisions start "
"with '%s': %s..."
% (resolved_id, ", ".join("'%s'" % r for r in revs[0:3])),
resolved_id,
)
else:
revision = self._revision_map[revs[0]]
if check_branch and revision is not None:
assert branch_rev is not None
assert resolved_id
if not self._shares_lineage(
revision.revision, branch_rev.revision
):
raise ResolutionError(
"Revision %s is not a member of branch '%s'"
% (revision.revision, check_branch),
resolved_id,
)
return revision
def _filter_into_branch_heads(
self, targets: Iterable[Optional[_RevisionOrBase]]
) -> Set[Optional[_RevisionOrBase]]:
targets = set(targets)
for rev in list(targets):
assert rev
if targets.intersection(
self._get_descendant_nodes([rev], include_dependencies=False)
).difference([rev]):
targets.discard(rev)
return targets
def filter_for_lineage(
self,
targets: Iterable[_TR],
check_against: Optional[str],
include_dependencies: bool = False,
) -> Tuple[_TR, ...]:
id_, branch_label = self._resolve_revision_number(check_against)
shares = []
if branch_label:
shares.append(branch_label)
if id_:
shares.extend(id_)
return tuple(
tg
for tg in targets
if self._shares_lineage(
tg, shares, include_dependencies=include_dependencies
)
)
def _shares_lineage(
self,
target: Optional[_RevisionOrStr],
test_against_revs: Sequence[_RevisionOrStr],
include_dependencies: bool = False,
) -> bool:
if not test_against_revs:
return True
if not isinstance(target, Revision):
resolved_target = not_none(self._revision_for_ident(target))
else:
resolved_target = target
resolved_test_against_revs = [
self._revision_for_ident(test_against_rev)
if not isinstance(test_against_rev, Revision)
else test_against_rev
for test_against_rev in util.to_tuple(
test_against_revs, default=()
)
]
return bool(
set(
self._get_descendant_nodes(
[resolved_target],
include_dependencies=include_dependencies,
)
)
.union(
self._get_ancestor_nodes(
[resolved_target],
include_dependencies=include_dependencies,
)
)
.intersection(resolved_test_against_revs)
)
def _resolve_revision_number(
self, id_: Optional[_GetRevArg]
) -> Tuple[Tuple[str, ...], Optional[str]]:
branch_label: Optional[str]
if isinstance(id_, str) and "@" in id_:
branch_label, id_ = id_.split("@", 1)
elif id_ is not None and (
(isinstance(id_, tuple) and id_ and not isinstance(id_[0], str))
or not isinstance(id_, (str, tuple))
):
raise RevisionError(
"revision identifier %r is not a string; ensure database "
"driver settings are correct" % (id_,)
)
else:
branch_label = None
# ensure map is loaded
self._revision_map
if id_ == "heads":
if branch_label:
return (
self.filter_for_lineage(self.heads, branch_label),
branch_label,
)
else:
return self._real_heads, branch_label
elif id_ == "head":
current_head = self.get_current_head(branch_label)
if current_head:
return (current_head,), branch_label
else:
return (), branch_label
elif id_ == "base" or id_ is None:
return (), branch_label
else:
return util.to_tuple(id_, default=None), branch_label
def iterate_revisions(
self,
upper: _RevisionIdentifierType,
lower: _RevisionIdentifierType,
implicit_base: bool = False,
inclusive: bool = False,
assert_relative_length: bool = True,
select_for_downgrade: bool = False,
) -> Iterator[Revision]:
"""Iterate through script revisions, starting at the given
upper revision identifier and ending at the lower.
The traversal uses strictly the `down_revision`
marker inside each migration script, so
it is a requirement that upper >= lower,
else you'll get nothing back.
The iterator yields :class:`.Revision` objects.
"""
fn: _CollectRevisionsProtocol
if select_for_downgrade:
fn = self._collect_downgrade_revisions
else:
fn = self._collect_upgrade_revisions
revisions, heads = fn(
upper,
lower,
inclusive=inclusive,
implicit_base=implicit_base,
assert_relative_length=assert_relative_length,
)
for node in self._topological_sort(revisions, heads):
yield not_none(self.get_revision(node))
def _get_descendant_nodes(
self,
targets: Collection[Optional[_RevisionOrBase]],
map_: Optional[_RevisionMapType] = None,
check: bool = False,
omit_immediate_dependencies: bool = False,
include_dependencies: bool = True,
) -> Iterator[Any]:
if omit_immediate_dependencies:
def fn(rev: Revision) -> Iterable[str]:
if rev not in targets:
return rev._all_nextrev
else:
return rev.nextrev
elif include_dependencies:
def fn(rev: Revision) -> Iterable[str]:
return rev._all_nextrev
else:
def fn(rev: Revision) -> Iterable[str]:
return rev.nextrev
return self._iterate_related_revisions(
fn, targets, map_=map_, check=check
)
def _get_ancestor_nodes(
self,
targets: Collection[Optional[_RevisionOrBase]],
map_: Optional[_RevisionMapType] = None,
check: bool = False,
include_dependencies: bool = True,
) -> Iterator[Revision]:
if include_dependencies:
def fn(rev: Revision) -> Iterable[str]:
return rev._normalized_down_revisions
else:
def fn(rev: Revision) -> Iterable[str]:
return rev._versioned_down_revisions
return self._iterate_related_revisions(
fn, targets, map_=map_, check=check
)
def _iterate_related_revisions(
self,
fn: Callable[[Revision], Iterable[str]],
targets: Collection[Optional[_RevisionOrBase]],
map_: Optional[_RevisionMapType],
check: bool = False,
) -> Iterator[Revision]:
if map_ is None:
map_ = self._revision_map
seen = set()
todo: Deque[Revision] = collections.deque()
for target_for in targets:
target = is_revision(target_for)
todo.append(target)
if check:
per_target = set()
while todo:
rev = todo.pop()
if check:
per_target.add(rev)
if rev in seen:
continue
seen.add(rev)
# Check for map errors before collecting.
for rev_id in fn(rev):
next_rev = map_[rev_id]
assert next_rev is not None
if next_rev.revision != rev_id:
raise RevisionError(
"Dependency resolution failed; broken map"
)
todo.append(next_rev)
yield rev
if check:
overlaps = per_target.intersection(targets).difference(
[target]
)
if overlaps:
raise RevisionError(
"Requested revision %s overlaps with "
"other requested revisions %s"
% (
target.revision,
", ".join(r.revision for r in overlaps),
)
)
def _topological_sort(
self,
revisions: Collection[Revision],
heads: Any,
) -> List[str]:
"""Yield revision ids of a collection of Revision objects in
topological sorted order (i.e. revisions always come after their
down_revisions and dependencies). Uses the order of keys in
_revision_map to sort.
"""
id_to_rev = self._revision_map
def get_ancestors(rev_id: str) -> Set[str]:
return {
r.revision
for r in self._get_ancestor_nodes([id_to_rev[rev_id]])
}
todo = {d.revision for d in revisions}
# Use revision map (ordered dict) key order to pre-sort.
inserted_order = list(self._revision_map)
current_heads = list(
sorted(
{d.revision for d in heads if d.revision in todo},
key=inserted_order.index,
)
)
ancestors_by_idx = [get_ancestors(rev_id) for rev_id in current_heads]
output = []
current_candidate_idx = 0
while current_heads:
candidate = current_heads[current_candidate_idx]
for check_head_index, ancestors in enumerate(ancestors_by_idx):
# scan all the heads. see if we can continue walking
# down the current branch indicated by current_candidate_idx.
if (
check_head_index != current_candidate_idx
and candidate in ancestors
):
current_candidate_idx = check_head_index
# nope, another head is dependent on us, they have
# to be traversed first
break
else:
# yup, we can emit
if candidate in todo:
output.append(candidate)
todo.remove(candidate)
# now update the heads with our ancestors.
candidate_rev = id_to_rev[candidate]
assert candidate_rev is not None
heads_to_add = [
r
for r in candidate_rev._normalized_down_revisions
if r in todo and r not in current_heads
]
if not heads_to_add:
# no ancestors, so remove this head from the list
del current_heads[current_candidate_idx]
del ancestors_by_idx[current_candidate_idx]
current_candidate_idx = max(current_candidate_idx - 1, 0)
else:
if (
not candidate_rev._normalized_resolved_dependencies
and len(candidate_rev._versioned_down_revisions) == 1
):
current_heads[current_candidate_idx] = heads_to_add[0]
# for plain movement down a revision line without
# any mergepoints, branchpoints, or deps, we
# can update the ancestors collection directly
# by popping out the candidate we just emitted
ancestors_by_idx[current_candidate_idx].discard(
candidate
)
else:
# otherwise recalculate it again, things get
# complicated otherwise. This can possibly be
# improved to not run the whole ancestor thing
# each time but it was getting complicated
current_heads[current_candidate_idx] = heads_to_add[0]
current_heads.extend(heads_to_add[1:])
ancestors_by_idx[
current_candidate_idx
] = get_ancestors(heads_to_add[0])
ancestors_by_idx.extend(
get_ancestors(head) for head in heads_to_add[1:]
)
assert not todo
return output
def _walk(
self,
start: Optional[Union[str, Revision]],
steps: int,
branch_label: Optional[str] = None,
no_overwalk: bool = True,
) -> Optional[_RevisionOrBase]:
"""
Walk the requested number of :steps up (steps > 0) or down (steps < 0)
the revision tree.
:branch_label is used to select branches only when walking up.
If the walk goes past the boundaries of the tree and :no_overwalk is
True, None is returned, otherwise the walk terminates early.
A RevisionError is raised if there is no unambiguous revision to
walk to.
"""
initial: Optional[_RevisionOrBase]
if isinstance(start, str):
initial = self.get_revision(start)
else:
initial = start
children: Sequence[Optional[_RevisionOrBase]]
for _ in range(abs(steps)):
if steps > 0:
assert initial != "base" # type: ignore[comparison-overlap]
# Walk up
walk_up = [
is_revision(rev)
for rev in self.get_revisions(
self.bases if initial is None else initial.nextrev
)
]
if branch_label:
children = self.filter_for_lineage(walk_up, branch_label)
else:
children = walk_up
else:
# Walk down
if initial == "base": # type: ignore[comparison-overlap]
children = ()
else:
children = self.get_revisions(
self.heads
if initial is None
else initial.down_revision
)
if not children:
children = ("base",)
if not children:
# This will return an invalid result if no_overwalk, otherwise
# further steps will stay where we are.
ret = None if no_overwalk else initial
return ret
elif len(children) > 1:
raise RevisionError("Ambiguous walk")
initial = children[0]
return initial
def _parse_downgrade_target(
self,
current_revisions: _RevisionIdentifierType,
target: _RevisionIdentifierType,
assert_relative_length: bool,
) -> Tuple[Optional[str], Optional[_RevisionOrBase]]:
"""
Parse downgrade command syntax :target to retrieve the target revision
and branch label (if any) given the :current_revisions stamp of the
database.
Returns a tuple (branch_label, target_revision) where branch_label
is a string from the command specifying the branch to consider (or
None if no branch given), and target_revision is a Revision object
which the command refers to. target_revisions is None if the command
refers to 'base'. The target may be specified in absolute form, or
relative to :current_revisions.
"""
if target is None:
return None, None
assert isinstance(
target, str
), "Expected downgrade target in string form"
match = _relative_destination.match(target)
if match:
branch_label, symbol, relative = match.groups()
rel_int = int(relative)
if rel_int >= 0:
if symbol is None:
# Downgrading to current + n is not valid.
raise RevisionError(
"Relative revision %s didn't "
"produce %d migrations" % (relative, abs(rel_int))
)
# Find target revision relative to given symbol.
rev = self._walk(
symbol,
rel_int,
branch_label,
no_overwalk=assert_relative_length,
)
if rev is None:
raise RevisionError("Walked too far")
return branch_label, rev
else:
relative_revision = symbol is None
if relative_revision:
# Find target revision relative to current state.
if branch_label:
cr_tuple = util.to_tuple(current_revisions)
symbol_list: Sequence[str]
symbol_list = self.filter_for_lineage(
cr_tuple, branch_label
)
if not symbol_list:
# check the case where there are multiple branches
# but there is currently a single heads, since all
# other branch heads are dependent of the current
# single heads.
all_current = cast(
Set[Revision], self._get_all_current(cr_tuple)
)
sl_all_current = self.filter_for_lineage(
all_current, branch_label
)
symbol_list = [
r.revision if r else r # type: ignore[misc]
for r in sl_all_current
]
assert len(symbol_list) == 1
symbol = symbol_list[0]
else:
current_revisions = util.to_tuple(current_revisions)
if not current_revisions:
raise RevisionError(
"Relative revision %s didn't "
"produce %d migrations"
% (relative, abs(rel_int))
)
# Have to check uniques here for duplicate rows test.
if len(set(current_revisions)) > 1:
util.warn(
"downgrade -1 from multiple heads is "
"ambiguous; "
"this usage will be disallowed in a future "
"release."
)
symbol = current_revisions[0]
# Restrict iteration to just the selected branch when
# ambiguous branches are involved.
branch_label = symbol
# Walk down the tree to find downgrade target.
rev = self._walk(
start=self.get_revision(symbol)
if branch_label is None
else self.get_revision("%s@%s" % (branch_label, symbol)),
steps=rel_int,
no_overwalk=assert_relative_length,
)
if rev is None:
if relative_revision:
raise RevisionError(
"Relative revision %s didn't "
"produce %d migrations" % (relative, abs(rel_int))
)
else:
raise RevisionError("Walked too far")
return branch_label, rev
# No relative destination given, revision specified is absolute.
branch_label, _, symbol = target.rpartition("@")
if not branch_label:
branch_label = None
return branch_label, self.get_revision(symbol)
def _parse_upgrade_target(
self,
current_revisions: _RevisionIdentifierType,
target: _RevisionIdentifierType,
assert_relative_length: bool,
) -> Tuple[Optional[_RevisionOrBase], ...]:
"""
Parse upgrade command syntax :target to retrieve the target revision
and given the :current_revisions stamp of the database.
Returns a tuple of Revision objects which should be iterated/upgraded
to. The target may be specified in absolute form, or relative to
:current_revisions.
"""
if isinstance(target, str):
match = _relative_destination.match(target)
else:
match = None
if not match:
# No relative destination, target is absolute.
return self.get_revisions(target)
current_revisions_tup: Union[str, Tuple[Optional[str], ...], None]
current_revisions_tup = util.to_tuple(current_revisions)
branch_label, symbol, relative_str = match.groups()
relative = int(relative_str)
if relative > 0:
if symbol is None:
if not current_revisions_tup:
current_revisions_tup = (None,)
# Try to filter to a single target (avoid ambiguous branches).
start_revs = current_revisions_tup
if branch_label:
start_revs = self.filter_for_lineage(
self.get_revisions(current_revisions_tup), # type: ignore[arg-type] # noqa: E501
branch_label,
)
if not start_revs:
# The requested branch is not a head, so we need to
# backtrack to find a branchpoint.
active_on_branch = self.filter_for_lineage(
self._get_ancestor_nodes(
self.get_revisions(current_revisions_tup)
),
branch_label,
)
# Find the tips of this set of revisions (revisions
# without children within the set).
start_revs = tuple(
{rev.revision for rev in active_on_branch}
- {
down
for rev in active_on_branch
for down in rev._normalized_down_revisions
}
)
if not start_revs:
# We must need to go right back to base to find
# a starting point for this branch.
start_revs = (None,)
if len(start_revs) > 1:
raise RevisionError(
"Ambiguous upgrade from multiple current revisions"
)
# Walk up from unique target revision.
rev = self._walk(
start=start_revs[0],
steps=relative,
branch_label=branch_label,
no_overwalk=assert_relative_length,
)
if rev is None:
raise RevisionError(
"Relative revision %s didn't "
"produce %d migrations" % (relative_str, abs(relative))
)
return (rev,)
else:
# Walk is relative to a given revision, not the current state.
return (
self._walk(
start=self.get_revision(symbol),
steps=relative,
branch_label=branch_label,
no_overwalk=assert_relative_length,
),
)
else:
if symbol is None:
# Upgrading to current - n is not valid.
raise RevisionError(
"Relative revision %s didn't "
"produce %d migrations" % (relative, abs(relative))
)
return (
self._walk(
start=self.get_revision(symbol)
if branch_label is None
else self.get_revision("%s@%s" % (branch_label, symbol)),
steps=relative,
no_overwalk=assert_relative_length,
),
)
def _collect_downgrade_revisions(
self,
upper: _RevisionIdentifierType,
lower: _RevisionIdentifierType,
inclusive: bool,
implicit_base: bool,
assert_relative_length: bool,
) -> Tuple[Set[Revision], Tuple[Optional[_RevisionOrBase], ...]]:
"""
Compute the set of current revisions specified by :upper, and the
downgrade target specified by :target. Return all dependents of target
which are currently active.
:inclusive=True includes the target revision in the set
"""
branch_label, target_revision = self._parse_downgrade_target(
current_revisions=upper,
target=lower,
assert_relative_length=assert_relative_length,
)
if target_revision == "base":
target_revision = None
assert target_revision is None or isinstance(target_revision, Revision)
roots: List[Revision]
# Find candidates to drop.
if target_revision is None:
# Downgrading back to base: find all tree roots.
roots = [
rev
for rev in self._revision_map.values()
if rev is not None and rev.down_revision is None
]
elif inclusive:
# inclusive implies target revision should also be dropped
roots = [target_revision]
else:
# Downgrading to fixed target: find all direct children.
roots = [
is_revision(rev)
for rev in self.get_revisions(target_revision.nextrev)
]
if branch_label and len(roots) > 1:
# Need to filter roots.
ancestors = {
rev.revision
for rev in self._get_ancestor_nodes(
[self._resolve_branch(branch_label)],
include_dependencies=False,
)
}
# Intersection gives the root revisions we are trying to
# rollback with the downgrade.
roots = [
is_revision(rev)
for rev in self.get_revisions(
{rev.revision for rev in roots}.intersection(ancestors)
)
]
# Ensure we didn't throw everything away when filtering branches.
if len(roots) == 0:
raise RevisionError(
"Not a valid downgrade target from current heads"
)
heads = self.get_revisions(upper)
# Aim is to drop :branch_revision; to do so we also need to drop its
# descendents and anything dependent on it.
downgrade_revisions = set(
self._get_descendant_nodes(
roots,
include_dependencies=True,
omit_immediate_dependencies=False,
)
)
active_revisions = set(
self._get_ancestor_nodes(heads, include_dependencies=True)
)
# Emit revisions to drop in reverse topological sorted order.
downgrade_revisions.intersection_update(active_revisions)
if implicit_base:
# Wind other branches back to base.
downgrade_revisions.update(
active_revisions.difference(self._get_ancestor_nodes(roots))
)
if (
target_revision is not None
and not downgrade_revisions
and target_revision not in heads
):
# Empty intersection: target revs are not present.
raise RangeNotAncestorError("Nothing to drop", upper)
return downgrade_revisions, heads
def _collect_upgrade_revisions(
self,
upper: _RevisionIdentifierType,
lower: _RevisionIdentifierType,
inclusive: bool,
implicit_base: bool,
assert_relative_length: bool,
) -> Tuple[Set[Revision], Tuple[Revision, ...]]:
"""
Compute the set of required revisions specified by :upper, and the
current set of active revisions specified by :lower. Find the
difference between the two to compute the required upgrades.
:inclusive=True includes the current/lower revisions in the set
:implicit_base=False only returns revisions which are downstream
of the current/lower revisions. Dependencies from branches with
different bases will not be included.
"""
targets: Collection[Revision] = [
is_revision(rev)
for rev in self._parse_upgrade_target(
current_revisions=lower,
target=upper,
assert_relative_length=assert_relative_length,
)
]
# assert type(targets) is tuple, "targets should be a tuple"
# Handled named bases (e.g. branch@... -> heads should only produce
# targets on the given branch)
if isinstance(lower, str) and "@" in lower:
branch, _, _ = lower.partition("@")
branch_rev = self.get_revision(branch)
if branch_rev is not None and branch_rev.revision == branch:
# A revision was used as a label; get its branch instead
assert len(branch_rev.branch_labels) == 1
branch = next(iter(branch_rev.branch_labels))
targets = {
need for need in targets if branch in need.branch_labels
}
required_node_set = set(
self._get_ancestor_nodes(
targets, check=True, include_dependencies=True
)
).union(targets)
current_revisions = self.get_revisions(lower)
if not implicit_base and any(
rev not in required_node_set
for rev in current_revisions
if rev is not None
):
raise RangeNotAncestorError(lower, upper)
assert (
type(current_revisions) is tuple
), "current_revisions should be a tuple"
# Special case where lower = a relative value (get_revisions can't
# find it)
if current_revisions and current_revisions[0] is None:
_, rev = self._parse_downgrade_target(
current_revisions=upper,
target=lower,
assert_relative_length=assert_relative_length,
)
assert rev
if rev == "base":
current_revisions = tuple()
lower = None
else:
current_revisions = (rev,)
lower = rev.revision
current_node_set = set(
self._get_ancestor_nodes(
current_revisions, check=True, include_dependencies=True
)
).union(current_revisions)
needs = required_node_set.difference(current_node_set)
# Include the lower revision (=current_revisions?) in the iteration
if inclusive:
needs.update(is_revision(rev) for rev in self.get_revisions(lower))
# By default, base is implicit as we want all dependencies returned.
# Base is also implicit if lower = base
# implicit_base=False -> only return direct downstreams of
# current_revisions
if current_revisions and not implicit_base:
lower_descendents = self._get_descendant_nodes(
[is_revision(rev) for rev in current_revisions],
check=True,
include_dependencies=False,
)
needs.intersection_update(lower_descendents)
return needs, tuple(targets)
def _get_all_current(
self, id_: Tuple[str, ...]
) -> Set[Optional[_RevisionOrBase]]:
top_revs: Set[Optional[_RevisionOrBase]]
top_revs = set(self.get_revisions(id_))
top_revs.update(
self._get_ancestor_nodes(list(top_revs), include_dependencies=True)
)
return self._filter_into_branch_heads(top_revs)
class Revision:
"""Base class for revisioned objects.
The :class:`.Revision` class is the base of the more public-facing
:class:`.Script` object, which represents a migration script.
The mechanics of revision management and traversal are encapsulated
within :class:`.Revision`, while :class:`.Script` applies this logic
to Python files in a version directory.
"""
nextrev: FrozenSet[str] = frozenset()
"""following revisions, based on down_revision only."""
_all_nextrev: FrozenSet[str] = frozenset()
revision: str = None # type: ignore[assignment]
"""The string revision number."""
down_revision: Optional[_RevIdType] = None
"""The ``down_revision`` identifier(s) within the migration script.
Note that the total set of "down" revisions is
down_revision + dependencies.
"""
dependencies: Optional[_RevIdType] = None
"""Additional revisions which this revision is dependent on.
From a migration standpoint, these dependencies are added to the
down_revision to form the full iteration. However, the separation
of down_revision from "dependencies" is to assist in navigating
a history that contains many branches, typically a multi-root scenario.
"""
branch_labels: Set[str] = None # type: ignore[assignment]
"""Optional string/tuple of symbolic names to apply to this
revision's branch"""
_resolved_dependencies: Tuple[str, ...]
_normalized_resolved_dependencies: Tuple[str, ...]
@classmethod
def verify_rev_id(cls, revision: str) -> None:
illegal_chars = set(revision).intersection(_revision_illegal_chars)
if illegal_chars:
raise RevisionError(
"Character(s) '%s' not allowed in revision identifier '%s'"
% (", ".join(sorted(illegal_chars)), revision)
)
def __init__(
self,
revision: str,
down_revision: Optional[Union[str, Tuple[str, ...]]],
dependencies: Optional[Union[str, Tuple[str, ...]]] = None,
branch_labels: Optional[Union[str, Tuple[str, ...]]] = None,
) -> None:
if down_revision and revision in util.to_tuple(down_revision):
raise LoopDetected(revision)
elif dependencies is not None and revision in util.to_tuple(
dependencies
):
raise DependencyLoopDetected(revision)
self.verify_rev_id(revision)
self.revision = revision
self.down_revision = tuple_rev_as_scalar(util.to_tuple(down_revision))
self.dependencies = tuple_rev_as_scalar(util.to_tuple(dependencies))
self._orig_branch_labels = util.to_tuple(branch_labels, default=())
self.branch_labels = set(self._orig_branch_labels)
def __repr__(self) -> str:
args = [repr(self.revision), repr(self.down_revision)]
if self.dependencies:
args.append("dependencies=%r" % (self.dependencies,))
if self.branch_labels:
args.append("branch_labels=%r" % (self.branch_labels,))
return "%s(%s)" % (self.__class__.__name__, ", ".join(args))
def add_nextrev(self, revision: Revision) -> None:
self._all_nextrev = self._all_nextrev.union([revision.revision])
if self.revision in revision._versioned_down_revisions:
self.nextrev = self.nextrev.union([revision.revision])
@property
def _all_down_revisions(self) -> Tuple[str, ...]:
return util.dedupe_tuple(
util.to_tuple(self.down_revision, default=())
+ self._resolved_dependencies
)
@property
def _normalized_down_revisions(self) -> Tuple[str, ...]:
"""return immediate down revisions for a rev, omitting dependencies
that are still dependencies of ancestors.
"""
return util.dedupe_tuple(
util.to_tuple(self.down_revision, default=())
+ self._normalized_resolved_dependencies
)
@property
def _versioned_down_revisions(self) -> Tuple[str, ...]:
return util.to_tuple(self.down_revision, default=())
@property
def is_head(self) -> bool:
"""Return True if this :class:`.Revision` is a 'head' revision.
This is determined based on whether any other :class:`.Script`
within the :class:`.ScriptDirectory` refers to this
:class:`.Script`. Multiple heads can be present.
"""
return not bool(self.nextrev)
@property
def _is_real_head(self) -> bool:
return not bool(self._all_nextrev)
@property
def is_base(self) -> bool:
"""Return True if this :class:`.Revision` is a 'base' revision."""
return self.down_revision is None
@property
def _is_real_base(self) -> bool:
"""Return True if this :class:`.Revision` is a "real" base revision,
e.g. that it has no dependencies either."""
# we use self.dependencies here because this is called up
# in initialization where _real_dependencies isn't set up
# yet
return self.down_revision is None and self.dependencies is None
@property
def is_branch_point(self) -> bool:
"""Return True if this :class:`.Script` is a branch point.
A branchpoint is defined as a :class:`.Script` which is referred
to by more than one succeeding :class:`.Script`, that is more
than one :class:`.Script` has a `down_revision` identifier pointing
here.
"""
return len(self.nextrev) > 1
@property
def _is_real_branch_point(self) -> bool:
"""Return True if this :class:`.Script` is a 'real' branch point,
taking into account dependencies as well.
"""
return len(self._all_nextrev) > 1
@property
def is_merge_point(self) -> bool:
"""Return True if this :class:`.Script` is a merge point."""
return len(self._versioned_down_revisions) > 1
@overload
def tuple_rev_as_scalar(rev: None) -> None:
...
@overload
def tuple_rev_as_scalar(
rev: Union[Tuple[_T, ...], List[_T]]
) -> Union[_T, Tuple[_T, ...], List[_T]]:
...
def tuple_rev_as_scalar(
rev: Optional[Sequence[_T]],
) -> Union[_T, Sequence[_T], None]:
if not rev:
return None
elif len(rev) == 1:
return rev[0]
else:
return rev
def is_revision(rev: Any) -> Revision:
assert isinstance(rev, Revision)
return rev
|