Reflect "NO ACTION" as None; support "RESTRICT"

The "NO ACTION" keyword for foreign key "ON UPDATE" is now considered to be
the default cascade for a foreign key on all supporting backends (SQlite,
MySQL, PostgreSQL) and when detected is not included in the reflection
dictionary; this is already the behavior for PostgreSQL and MySQL for all
previous SQLAlchemy versions in any case.   The "RESTRICT" keyword is
positively stored when detected; PostgreSQL does report on this keyword,
and MySQL as of version 8.0 does as well.  On earlier MySQL versions, it is
not reported by the database.

Fixes: #4741
Change-Id: I6becf1f2450605c1991158bb8a04d954dcc7396c

1 files changed, 22 insertions, 2 deletions

diff --git a/lib/sqlalchemy/testing/suite/test_reflection.py b/lib/sqlalchemy/testing/suite/test_reflection.py
index e529a0753..53e1599b3 100644
--- a/lib/sqlalchemy/testing/suite/test_reflection.py
+++ b/lib/sqlalchemy/testing/suite/test_reflection.py
@@ -671,10 +671,29 @@ class ComponentReflectionTest(fixtures.TablesTest):
     def test_get_foreign_key_options_onupdate(self):
         self._test_get_foreign_key_options(onupdate="SET NULL")
 
+    @testing.requires.foreign_key_constraint_option_reflection_onupdate
+    def test_get_foreign_key_options_onupdate_noaction(self):
+        self._test_get_foreign_key_options(onupdate="NO ACTION", expected={})
+
+    @testing.requires.fk_constraint_option_reflection_ondelete_noaction
+    def test_get_foreign_key_options_ondelete_noaction(self):
+        self._test_get_foreign_key_options(ondelete="NO ACTION", expected={})
+
+    @testing.requires.fk_constraint_option_reflection_onupdate_restrict
+    def test_get_foreign_key_options_onupdate_restrict(self):
+        self._test_get_foreign_key_options(onupdate="RESTRICT")
+
+    @testing.requires.fk_constraint_option_reflection_ondelete_restrict
+    def test_get_foreign_key_options_ondelete_restrict(self):
+        self._test_get_foreign_key_options(ondelete="RESTRICT")
+
     @testing.provide_metadata
-    def _test_get_foreign_key_options(self, **options):
+    def _test_get_foreign_key_options(self, expected=None, **options):
         meta = self.metadata
 
+        if expected is None:
+            expected = options
+
         Table(
             "x",
             meta,
@@ -714,7 +733,8 @@ class ComponentReflectionTest(fixtures.TablesTest):
         eq_(dict((k, opts[k]) for k in opts if opts[k]), {})
 
         opts = insp.get_foreign_keys("user")[0]["options"]
-        eq_(dict((k, opts[k]) for k in opts if opts[k]), options)
+        eq_(opts, expected)
+        # eq_(dict((k, opts[k]) for k in opts if opts[k]), expected)
 
     def _assert_insp_indexes(self, indexes, expected_indexes):
         index_names = [d["name"] for d in indexes]