Ban generators in 7.0.0

bindings/python/fdb/impl.py

@@ -252,6 +252,12 @@ def transactional(*tr_args, **tr_kwargs):
         else:
             @functools.wraps(func)
             def wrapper(*args, **kwargs):
+                # We can't throw this from the decorator, as when a user runs
+                # >>> import fdb ; fdb.api_version(700)
+                # the code above uses @transactional before the API version is set
+                if fdb.get_api_version() >= 700 and inspect.isgeneratorfunction(func):
+                    raise ValueError("Generators can not be wrapped with fdb.transactional")
+
                 if isinstance(args[index], TransactionRead):
                     return func(*args, **kwargs)
 
@@ -267,14 +273,13 @@ def transactional(*tr_args, **tr_kwargs):
                     ret = None
                     try:
                         ret = func(*largs, **kwargs)
+                        if fdb.get_api_version() >= 700 and inspect.isgenerator(ret):
+                            raise ValueError("Generators can not be wrapped with fdb.transactional")
                         tr.commit().wait()
                         committed = True
                     except FDBError as e:
                         tr.on_error(e.code).wait()
 
-                    if fdb.get_api_version() >= 620 and isinstance(ret, types.GeneratorType):
-                        raise ValueError("Generators can not be wrapped with fdb.transactional")
-
                     # now = datetime.datetime.now()
                     # td = now - last
                     # elapsed = (td.microseconds + (td.seconds + td.days * 24 * 3600) * 10**6) / float(10**6)

bindings/python/tests/tester.py

@@ -132,10 +132,22 @@ def test_fdb_transactional_generator(db):
         @fdb.transactional
         def function_that_yields(tr):
             yield 0
-        function_that_yields(db)
-        assert fdb.get_api_version() < 620, "Generators post-6.2.0 should throw"
+        assert fdb.get_api_version() < 700, "Pre-7.0, a decorators may wrap a function that yield"
     except ValueError as e:
-        pass
+        assert fdb.get_api_version() >= 700, "Post-7.0, a decorator should throw if wrapped function yields"
+
+
+def test_fdb_transactional_returns_generator(db):
+    try:
+        def function_that_yields(tr):
+            yield 0
+        @fdb.transactional
+        def function_that_returns(tr):
+            return function_that_yields(tr)
+        function_that_returns()
+        assert fdb.get_api_version() < 700, "Pre-7.0, returning a generator is allowed"
+    except ValueError as e:
+        assert fdb.get_api_version() >= 700, "Post-7.0, returning a generator should throw"
 
 
 def test_db_options(db):