Avoid proxy functions in row functions

This streamlines a bit for non-C implementations, however
also adds and tests behavioral contracts that mappings should
not allow integer or slice access and should behave like a
Python mapping in that it raises KeyError for an integer
and TypeError for a slice.   Py3/Py2/C/noC :)

References: #5340
Change-Id: Id3cef452dc8a526b8371c90c5ca2bbb240b25c26

1 files changed, 12 insertions, 8 deletions

diff --git a/lib/sqlalchemy/engine/result.py b/lib/sqlalchemy/engine/result.py
index 109ab41fe..ce844eb40 100644
--- a/lib/sqlalchemy/engine/result.py
+++ b/lib/sqlalchemy/engine/result.py
@@ -40,7 +40,7 @@ else:
             operator.methodcaller("_get_by_key_impl_mapping", index)
             for index in indexes
         ]
-        return lambda rec: tuple(getter(rec) for getter in getters)
+        return lambda rec: tuple([getter(rec) for getter in getters])
 
 
 class ResultMetaData(object):
@@ -775,15 +775,19 @@ class Result(InPlaceGenerative):
             uniques, strategy = self._unique_strategy
 
             def filterrows(make_row, rows, strategy, uniques):
+                if strategy:
+                    made_rows = (
+                        (made_row, strategy(made_row))
+                        for made_row in [make_row(row) for row in rows]
+                    )
+                else:
+                    made_rows = (
+                        (made_row, made_row)
+                        for made_row in [make_row(row) for row in rows]
+                    )
                 return [
                     made_row
-                    for made_row, sig_row in [
-                        (
-                            made_row,
-                            strategy(made_row) if strategy else made_row,
-                        )
-                        for made_row in [make_row(row) for row in rows]
-                    ]
+                    for made_row, sig_row in made_rows
                     if sig_row not in uniques and not uniques.add(sig_row)
                 ]