- case() interprets the "THEN" expressions

as values by default, meaning case([(x==y, "foo")]) will
interpret "foo" as a bound value, not a SQL expression.
use text(expr) for literal SQL expressions in this case.
For the criterion itself, these may be literal strings
only if the "value" keyword is present, otherwise SA
will force explicit usage of either text() or literal().

1 files changed, 23 insertions, 12 deletions

diff --git a/test/sql/case_statement.py b/test/sql/case_statement.py
index 730517b21..257298c8e 100644
--- a/test/sql/case_statement.py
+++ b/test/sql/case_statement.py
@@ -2,10 +2,11 @@ import testenv; testenv.configure_for_tests()
 import sys
 from sqlalchemy import *
 from testlib import *
-from sqlalchemy import util
+from sqlalchemy import util, exceptions
+from sqlalchemy.sql import table, column
 
 
-class CaseTest(TestBase):
+class CaseTest(TestBase, AssertsCompiledSQL):
 
     def setUpAll(self):
         metadata = MetaData(testing.db)
@@ -30,9 +31,9 @@ class CaseTest(TestBase):
     def testcase(self):
         inner = select([case([
                 [info_table.c.pk < 3,
-                        literal('lessthan3', type_=String)],
+                        'lessthan3'],
         [and_(info_table.c.pk >= 3, info_table.c.pk < 7),
-                        literal('gt3', type_=String)]]).label('x'),
+                        'gt3']]).label('x'),
         info_table.c.pk, info_table.c.info],
                 from_obj=[info_table]).alias('q_inner')
 
@@ -69,9 +70,9 @@ class CaseTest(TestBase):
 
         w_else = select([case([
                 [info_table.c.pk < 3,
-                        literal(3, type_=Integer)],
+                        3],
         [and_(info_table.c.pk >= 3, info_table.c.pk < 6),
-                        literal(6, type_=Integer)]],
+                        6]],
                 else_ = 0).label('x'),
         info_table.c.pk, info_table.c.info],
                 from_obj=[info_table]).alias('q_inner')
@@ -87,12 +88,21 @@ class CaseTest(TestBase):
             (0, 6, 'pk_6_data')
         ]
 
+    def test_literal_interpretation(self):
+        t = table('test', column('col1'))
+        
+        self.assertRaises(exceptions.ArgumentError, case, [("x", "y")])
+        
+        self.assert_compile(case([("x", "y")], value=t.c.col1), "CASE test.col1 WHEN :param_1 THEN :param_2 END")
+        self.assert_compile(case([(t.c.col1==7, "y")], else_="z"), "CASE WHEN (test.col1 = :test_col1_1) THEN :param_1 ELSE :param_2 END")
+
+        
     @testing.fails_on('maxdb')
     def testcase_with_dict(self):
         query = select([case({
-                    info_table.c.pk < 3: literal('lessthan3'),
-                    info_table.c.pk >= 3: literal('gt3'),
-                }, else_=literal('other')),
+                    info_table.c.pk < 3: 'lessthan3',
+                    info_table.c.pk >= 3: 'gt3',
+                }, else_='other'),
                 info_table.c.pk, info_table.c.info
             ],
             from_obj=[info_table])
@@ -106,13 +116,14 @@ class CaseTest(TestBase):
         ]
 
         simple_query = select([case({
-                    1: literal('one'),
-                    2: literal('two'),
-                }, value=info_table.c.pk, else_=literal('other')),
+                    1: 'one',
+                    2: 'two',
+                }, value=info_table.c.pk, else_='other'),
                 info_table.c.pk
             ],
             whereclause=info_table.c.pk < 4,
             from_obj=[info_table])
+        
         assert simple_query.execute().fetchall() == [
             ('one', 1),
             ('two', 2),