From 77a17797ecc08736ea942e29f79df4f96bd74e0c Mon Sep 17 00:00:00 2001
From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Wed, 3 Nov 2021 21:26:44 -0400
Subject: use ExpressionElementRole for case targets in case()

Fixed regression where the :func:`_sql.text` construct would no longer be
accepted as a target case in the "whens" list within a :func:`_sql.case`
construct. The regression appears related to an attempt to guard against
some forms of literal values that were considered to be ambiguous when
passed here; however, there's no reason the target cases shouldn't be
interpreted as open-ended SQL expressions just like anywhere else, and a
literal string or tuple will be converted to a bound parameter as would be
the case elsewhere.

Fixes: #7287
Change-Id: I75478adfa115f3292cb1362cc5b2fdf152b0ed6f
---
 lib/sqlalchemy/sql/elements.py | 34 ++++++++++++----------------------
 1 file changed, 12 insertions(+), 22 deletions(-)

(limited to 'lib/sqlalchemy/sql')

diff --git a/lib/sqlalchemy/sql/elements.py b/lib/sqlalchemy/sql/elements.py
index f1fe46fd2..c8faebbd9 100644
--- a/lib/sqlalchemy/sql/elements.py
+++ b/lib/sqlalchemy/sql/elements.py
@@ -2943,28 +2943,18 @@ class Case(ColumnElement):
             pass
 
         value = kw.pop("value", None)
-        if value is not None:
-            whenlist = [
-                (
-                    coercions.expect(
-                        roles.ExpressionElementRole,
-                        c,
-                        apply_propagate_attrs=self,
-                    ).self_group(),
-                    coercions.expect(roles.ExpressionElementRole, r),
-                )
-                for (c, r) in whens
-            ]
-        else:
-            whenlist = [
-                (
-                    coercions.expect(
-                        roles.ColumnArgumentRole, c, apply_propagate_attrs=self
-                    ).self_group(),
-                    coercions.expect(roles.ExpressionElementRole, r),
-                )
-                for (c, r) in whens
-            ]
+
+        whenlist = [
+            (
+                coercions.expect(
+                    roles.ExpressionElementRole,
+                    c,
+                    apply_propagate_attrs=self,
+                ).self_group(),
+                coercions.expect(roles.ExpressionElementRole, r),
+            )
+            for (c, r) in whens
+        ]
 
         if whenlist:
             type_ = list(whenlist[-1])[-1].type
-- 
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