[FIX] util/pg: use the old column to check the type

It's the original column what we need to check, the target column would
have a different type.

See 353c206

closes #76

Signed-off-by: Christophe Simonis (chs) <[email protected]>

Author: aj-fuentes

src/base/tests/test_util.py

@@ -431,6 +431,30 @@ def test_iter_browse_call_twice(self):
 
 
 class TestPG(UnitTestCase):
+    def test_alter_column_type(self):
+        cr = self.env.cr
+        cr.execute(
+            """
+            ALTER TABLE res_partner_title ADD COLUMN x bool;
+
+            UPDATE res_partner_title
+               SET x = CASE id % 3
+                           WHEN 1 THEN NULL
+                           WHEN 2 THEN True
+                           ELSE False
+                       END
+            """
+        )
+        self.assertEqual(util.column_type(cr, "res_partner_title", "x"), "bool")
+        util.alter_column_type(cr, "res_partner_title", "x", "int", using="CASE {0} WHEN True THEN 2 ELSE 1 END")
+        self.assertEqual(util.column_type(cr, "res_partner_title", "x"), "int4")
+        cr.execute("SELECT id, x FROM res_partner_title")
+        data = cr.fetchall()
+        self.assertTrue(
+            all(x == 1 or (x == 2 and id_ % 3 == 2) for id_, x in data),
+            "Some values where not casted correctly via USING",
+        )
+
     @parametrize(
         [
             ("test", "<p>test</p>"),

src/util/pg.py

@@ -605,7 +605,7 @@ def alter_column_type(cr, table, column, type, using=None, logger=_logger):
 
     using = sql.SQL(format_query(cr, using, tmp_column))
     where_clause = sql.SQL("")
-    if column_type(cr, table, column) != "bool":
+    if column_type(cr, table, tmp_column) != "bool":
         where_clause = sql.SQL(format_query(cr, "WHERE {} IS NOT NULL", tmp_column))
     explode_execute(
         cr,