Merge lp:~rvb/storm/storm-0slice-bug-872086 into lp:storm

[Raphaël Badin]

Fix how SQLObjectResultSet handles slicing when slice.start and slice.end are both zero.

This branch fixes how SQLObjectResultSet handles slicing when the start and the end of the slice are 0 (sqlobj[0:0]).

= Tests =

tests/sqlobject.py
- test_result_set_count_sliced_empty
- test_result_set_count_sliced_empty_zero

[Gavin Panella (allenap)]

review: Approve

[Thomas Herve (therve)]

Looks good! please put a small note in the NEWS file and merge.

review: Approve

[lp:~rvb/storm/storm-0slice-bug-872086]

417. By Raphaël Badin on 2011-10-17

Add a note to NEWS.

[Robert Collins (lifeless)]

This is nearly right :) the if block you remove needs to stay and be tweaked though:
>>> range(10)[None:None]
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

review: Needs Fixing

[Raphaël Badin (rvb)]

Without changing the code, this test passes:

    def test_result_set_count_sliced_none(self):
        result = self.Person.select()
        sliced_result = result[None:None]
        self.assertEquals(len(list(sliced_result)), 2)
        self.assertEquals(sliced_result.count(), 2)

I think the limit and offset parameters being None is a case that is already taken care of by the code (also, result[1:None] and result[None:4] behave as expected).

[Robert Collins (lifeless)]

Awesome! May be worth adding those tests if they aren't there already,
as future proofing.

[Raphaël Badin (rvb)]

Good point, I've added the tests.

[Raphaël Badin (rvb)]

I've put the tests in a new branch, here is the mp: https://code.launchpad.net/~rvb/storm/storm-0slice-bug-872086-tests/+merge/79658.

=== modified file 'NEWS'
--- NEWS	2011-10-05 16:15:41 +0000
+++ NEWS	2011-10-17 18:35:26 +0000
@@ -7,6 +7,7 @@
 Bug fixes
 ---------
 
+- When a SQLObjectResultSet object was sliced with slice.start and slice.end both zero (sqlobject[0:0]), the full, unsliced resultset was returned (bug #872086).
 
 0.19 (2011-10-03)
 =================

=== modified file 'storm/sqlobject.py'
--- storm/sqlobject.py	2011-04-13 03:20:36 +0000
+++ storm/sqlobject.py	2011-10-17 18:35:26 +0000
@@ -525,9 +525,6 @@
 
     def __getitem__(self, index):
         if isinstance(index, slice):
-            if not index.start and not index.stop:
-                return self
-
             if index.start and index.start < 0 or (
                 index.stop and index.stop < 0):
                 L = list(self)

=== modified file 'tests/sqlobject.py'
--- tests/sqlobject.py	2010-10-12 12:02:01 +0000
+++ tests/sqlobject.py	2011-10-17 18:35:26 +0000
@@ -755,6 +755,18 @@
         self.assertEquals(len(list(sliced_result)), 1)
         self.assertEquals(sliced_result.count(), 1)
 
+    def test_result_set_count_sliced_empty(self):
+        result = self.Person.select()
+        sliced_result = result[1:1]
+        self.assertEquals(len(list(sliced_result)), 0)
+        self.assertEquals(sliced_result.count(), 0)
+
+    def test_result_set_count_sliced_empty_zero(self):
+        result = self.Person.select()
+        sliced_result = result[0:0]
+        self.assertEquals(len(list(sliced_result)), 0)
+        self.assertEquals(sliced_result.count(), 0)
+
     def test_result_set_count_distinct(self):
         result = self.Person.select(
             "person.id = phone.person_id",