GH-745: fix money-range floor + Copilot review findings

- Lower bound of the redeclare range is MONEY_MIN, not SMALLMONEY_MIN: a value like Decimal('-300000') is in the MONEY range but below SMALLMONEY_MIN and was left as SQL_VARCHAR, reintroducing the overflow on negative money-range values.
- Test: cover the negative-money-below-SMALLMONEY_MIN edge and the below-MONEY_MIN boundary; clarify the _ParamInfo docstring.

(Copilot columnSize concern is not reachable for the money range: money has <=4 decimal places so the string length is always <38 and the declared precision is never < the scale.)

Author: IMGillusion

mssql_python/cursor.py

@@ -2390,7 +2390,13 @@ def _apply_money_batch_declared_type(self, paraminfo, column):
         non_nulls = [v for v in column if v is not None]
         if not non_nulls or not all(isinstance(v, decimal.Decimal) for v in non_nulls):
             return False
-        if not all(SMALLMONEY_MIN <= v <= MONEY_MAX for v in non_nulls):
+        # The money shortcut (see _map_sql_type) string-binds any Decimal in
+        # the full MONEY range; SMALLMONEY is a subset of that range. The
+        # lower bound must be MONEY_MIN, not SMALLMONEY_MIN: a value like
+        # Decimal("-300000") is in the MONEY range but below SMALLMONEY_MIN,
+        # and using the smaller floor left such batches as SQL_VARCHAR,
+        # reintroducing the GH-745 overflow on negative money-range values.
+        if not all(MONEY_MIN <= v <= MONEY_MAX for v in non_nulls):
             return False
         paraminfo.paramSQLType = ddbc_sql_const.SQL_NUMERIC.value
         paraminfo.decimalDigits = max(

tests/test_020_money_smallmoney.py

@@ -530,7 +530,15 @@ def test_executemany_money_smallmoney(cursor, db_connection):
 
 
 class _ParamInfo:
-    """Duck-typed stand-in for ddbc_bindings.ParamInfo (no C extension needed)."""
+    """Duck-typed stand-in for ddbc_bindings.ParamInfo.
+
+    It avoids *constructing* a real ParamInfo (the pure-Python fields
+    `_apply_money_batch_declared_type` reads are enough), but the
+    `Cursor` import in `_bare_cursor` still pulls in the compiled
+    ddbc_bindings extension, so the test runs only where it is built
+    (CI); arm64 local runs stub the module (see the GH-745 red/green
+    script) rather than this file.
+    """
 
     def __init__(self, sql_type):
         self.paramSQLType = sql_type
@@ -570,6 +578,21 @@ def test_money_batch_redeclared_as_numeric():
     assert p.paramSQLType == numeric
     assert p.decimalDigits == 0
 
+    # Negative money-range value below SMALLMONEY_MIN but inside the MONEY
+    # range: must still redeclare (the MONEY_MIN floor, not the SMALLMONEY
+    # floor, is the correct lower bound). GH-745 negative-value edge.
+    p = _ParamInfo(varchar)
+    assert cur._apply_money_batch_declared_type(p, [Decimal("-300000")]) is True
+    assert p.paramSQLType == numeric
+    assert p.decimalDigits == 0
+
+    # Below MONEY_MIN (negative overflow) -> unchanged (not a money value)
+    p = _ParamInfo(varchar)
+    assert cur._apply_money_batch_declared_type(
+        p, [Decimal("-922337203685477.5809")]
+    ) is False
+    assert p.paramSQLType == varchar
+
     # Above MONEY_MAX -> unchanged (existing NUMERIC path handles it)
     p = _ParamInfo(varchar)
     assert cur._apply_money_batch_declared_type(p, [Decimal("9999999999999999")]) is False