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Merging upstream version 11.2.3.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-13 15:40:23 +01:00
parent c6f7c6bbe1
commit 428b7dd76f
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
93 changed files with 33054 additions and 31671 deletions
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55
sqlglot/diff.py
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@ -11,8 +11,7 @@ from collections import defaultdict
from dataclasses import dataclass
from heapq import heappop, heappush
from sqlglot import Dialect
from sqlglot import expressions as exp
from sqlglot import Dialect, expressions as exp
from sqlglot.helper import ensure_collection
@ -58,7 +57,12 @@ if t.TYPE_CHECKING:
Edit = t.Union[Insert, Remove, Move, Update, Keep]
def diff(source: exp.Expression, target: exp.Expression) -> t.List[Edit]:
def diff(
source: exp.Expression,
target: exp.Expression,
matchings: t.List[t.Tuple[exp.Expression, exp.Expression]] | None = None,
**kwargs: t.Any,
) -> t.List[Edit]:
"""
Returns the list of changes between the source and the target expressions.
@ -80,13 +84,38 @@ def diff(source: exp.Expression, target: exp.Expression) -> t.List[Edit]:
Args:
source: the source expression.
target: the target expression against which the diff should be calculated.
matchings: the list of pre-matched node pairs which is used to help the algorithm's
heuristics produce better results for subtrees that are known by a caller to be matching.
Note: expression references in this list must refer to the same node objects that are
referenced in source / target trees.
Returns:
the list of Insert, Remove, Move, Update and Keep objects for each node in the source and the
target expression trees. This list represents a sequence of steps needed to transform the source
expression tree into the target one.
"""
return ChangeDistiller().diff(source.copy(), target.copy())
matchings = matchings or []
matching_ids = {id(n) for pair in matchings for n in pair}
def compute_node_mappings(
original: exp.Expression, copy: exp.Expression
) -> t.Dict[int, exp.Expression]:
return {
id(old_node): new_node
for (old_node, _, _), (new_node, _, _) in zip(original.walk(), copy.walk())
if id(old_node) in matching_ids
}
source_copy = source.copy()
target_copy = target.copy()
node_mappings = {
**compute_node_mappings(source, source_copy),
**compute_node_mappings(target, target_copy),
}
matchings_copy = [(node_mappings[id(s)], node_mappings[id(t)]) for s, t in matchings]
return ChangeDistiller(**kwargs).diff(source_copy, target_copy, matchings=matchings_copy)
LEAF_EXPRESSION_TYPES = (
@ -109,16 +138,26 @@ class ChangeDistiller:
self.t = t
self._sql_generator = Dialect().generator()
def diff(self, source: exp.Expression, target: exp.Expression) -> t.List[Edit]:
def diff(
self,
source: exp.Expression,
target: exp.Expression,
matchings: t.List[t.Tuple[exp.Expression, exp.Expression]] | None = None,
) -> t.List[Edit]:
matchings = matchings or []
pre_matched_nodes = {id(s): id(t) for s, t in matchings}
if len({n for pair in pre_matched_nodes.items() for n in pair}) != 2 * len(matchings):
raise ValueError("Each node can be referenced at most once in the list of matchings")
self._source = source
self._target = target
self._source_index = {id(n[0]): n[0] for n in source.bfs()}
self._target_index = {id(n[0]): n[0] for n in target.bfs()}
self._unmatched_source_nodes = set(self._source_index)
self._unmatched_target_nodes = set(self._target_index)
self._unmatched_source_nodes = set(self._source_index) - set(pre_matched_nodes)
self._unmatched_target_nodes = set(self._target_index) - set(pre_matched_nodes.values())
self._bigram_histo_cache: t.Dict[int, t.DefaultDict[str, int]] = {}
matching_set = self._compute_matching_set()
matching_set = self._compute_matching_set() | {(s, t) for s, t in pre_matched_nodes.items()}
return self._generate_edit_script(matching_set)
def _generate_edit_script(self, matching_set: t.Set[t.Tuple[int, int]]) -> t.List[Edit]: