fix(NoTicket): vendor sqlparse CASE...END fix to allow PyPI publishing

Replace git dependency on lorenzhs/sqlparse fork with a monkey-patch of
StatementSplitter._change_splitlevel in statement_formatter.py.

The upstream sqlparse project isn't very active and the fix for CASE...END level
tracking (andialbrecht/sqlparse#839) was not yet
released.  PyPI rejects packages with VCS dependencies, so vendoring the fix
inline unblocks publishing.

Author: lorenzhs

setup.cfg

@@ -36,7 +36,7 @@ install_requires =
     pydantic[dotenv]>=1.8.2,<3.0.0
     python-dateutil>=2.8.2
     readerwriterlock>=1.0.9
-    sqlparse@git+https://github.com/lorenzhs/sqlparse.git@8d379386c1c3e103ee67ef6582ea1b7c2296aa5b
+    sqlparse>=0.5.5
     trio>=0.22.0
     truststore>=0.10;python_version>="3.10"
 python_requires = >=3.9

src/firebolt/common/statement_formatter.py

@@ -3,6 +3,10 @@
 from typing import Dict, List, Optional, Sequence, Union
 
 from sqlparse import parse as parse_sql  # type: ignore
+from sqlparse import tokens as _T
+from sqlparse.engine.statement_splitter import (
+    StatementSplitter as _StatementSplitter,
+)
 from sqlparse.sql import (  # type: ignore
     Comment,
     Comparison,
@@ -15,6 +19,78 @@
 from sqlparse.tokens import Whitespace  # type: ignore
 from sqlparse.tokens import Token as TokenType  # type: ignore
 
+
+def _patched_change_splitlevel(self, ttype, value):  # type: ignore[no-untyped-def]
+    """Patched version of StatementSplitter._change_splitlevel.
+
+    Fixes CASE...END level tracking outside of CREATE blocks.
+    See: https://github.com/andialbrecht/sqlparse/pull/839
+    """
+    if ttype is _T.Punctuation and value == "(":
+        return 1
+    elif ttype is _T.Punctuation and value == ")":
+        return -1
+    elif ttype not in _T.Keyword:
+        return 0
+
+    unified = value.upper()
+
+    if ttype is _T.Keyword.DDL and unified.startswith("CREATE"):
+        self._is_create = True
+        return 0
+
+    if unified == "DECLARE" and self._is_create and self._begin_depth == 0:
+        self._in_declare = True
+        return 1
+
+    if unified == "BEGIN":
+        self._begin_depth += 1
+        self._seen_begin = True
+        if self._is_create:
+            return 1
+        return 0
+
+    if (
+        self._seen_begin
+        and (ttype is _T.Keyword or ttype is _T.Name)
+        and unified
+        in (
+            "TRANSACTION",
+            "WORK",
+            "TRAN",
+            "DISTRIBUTED",
+            "DEFERRED",
+            "IMMEDIATE",
+            "EXCLUSIVE",
+        )
+    ):
+        self._begin_depth = max(0, self._begin_depth - 1)
+        self._seen_begin = False
+        return 0
+
+    if unified == "END":
+        if not self._in_case:
+            self._begin_depth = max(0, self._begin_depth - 1)
+        else:
+            self._in_case = False
+        return -1
+
+    if unified == "CASE":
+        self._in_case = True
+        return 1
+
+    if unified in ("IF", "FOR", "WHILE") and self._is_create and self._begin_depth > 0:
+        return 1
+
+    if unified in ("END IF", "END FOR", "END WHILE"):
+        return -1
+
+    return 0
+
+
+_StatementSplitter._change_splitlevel = _patched_change_splitlevel  # type: ignore[method-assign]
+
+
 from firebolt.common._types import ParameterType, SetParameter
 from firebolt.utils.exception import (
     DataError,