From 1042022dada72a0ce9be4a0b4c7843a00bce4c17 Mon Sep 17 00:00:00 2001
From: Bryant Khau <bryant.khau@equityzen.com>
Date: Tue, 5 May 2020 17:21:36 -0400
Subject: [PATCH 1/2] Avoid negative sizes in Search slice

---
 elasticsearch_dsl/search.py           | 1 +
 test_elasticsearch_dsl/test_search.py | 1 +
 2 files changed, 2 insertions(+)

diff --git a/elasticsearch_dsl/search.py b/elasticsearch_dsl/search.py
index 5b0196c1d..81e91d22d 100644
--- a/elasticsearch_dsl/search.py
+++ b/elasticsearch_dsl/search.py
@@ -345,6 +345,7 @@ def __getitem__(self, n):
             # stop not given.
             s._extra['from'] = n.start or 0
             s._extra['size'] = n.stop - (n.start or 0) if n.stop is not None else 10
+            s._extra['size'] = max(s._extra['size'], 0)
             return s
         else:  # This is an index lookup, equivalent to slicing by [n:n+1].
             # If negative index, abort.
diff --git a/test_elasticsearch_dsl/test_search.py b/test_elasticsearch_dsl/test_search.py
index 592a932d4..bdcf95182 100644
--- a/test_elasticsearch_dsl/test_search.py
+++ b/test_elasticsearch_dsl/test_search.py
@@ -237,6 +237,7 @@ def test_slice():
     assert {'from': 0, 'size': 5} == s[:5].to_dict()
     assert {'from': 3, 'size': 10} == s[3:].to_dict()
     assert {'from': 0, 'size': 0} == s[0:0].to_dict()
+    assert {'from': 20, 'size': 0} == s[20:0].to_dict()
 
 def test_index():
     s = search.Search()

From f7d5b4e362056f45c8050662fcde21e9cfd76bd2 Mon Sep 17 00:00:00 2001
From: bk-equityzen <37187683+bk-equityzen@users.noreply.github.com>
Date: Tue, 5 May 2020 17:39:53 -0400
Subject: [PATCH 2/2] Run max on same line when setting size

---
 elasticsearch_dsl/search.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/elasticsearch_dsl/search.py b/elasticsearch_dsl/search.py
index 81e91d22d..59c44c38d 100644
--- a/elasticsearch_dsl/search.py
+++ b/elasticsearch_dsl/search.py
@@ -344,8 +344,7 @@ def __getitem__(self, n):
             # Elasticsearch won't get all results so we default to size: 10 if
             # stop not given.
             s._extra['from'] = n.start or 0
-            s._extra['size'] = n.stop - (n.start or 0) if n.stop is not None else 10
-            s._extra['size'] = max(s._extra['size'], 0)
+            s._extra['size'] = max(0, n.stop - (n.start or 0) if n.stop is not None else 10)
             return s
         else:  # This is an index lookup, equivalent to slicing by [n:n+1].
             # If negative index, abort.