Add search tests: empty string and empty query (placeholder search)

Author: eskombro

meilisearch/tests/index/test_index_search_meilisearch.py

@@ -41,6 +41,18 @@ def test_basic_search_with_empty_params(self):
         assert response['hits'][0]['id'] == '166428'
         assert '_formatted' not in response['hits'][0]
 
+    def test_basic_search_with_empty_query(self):
+        """Tests search with empty query and empty params"""
+        response = self.index.search('', {})
+        assert isinstance(response, object)
+        assert len(response['hits']) == 0
+
+    def test_basic_search_with_placeholder(self):
+        """Tests search with no query [None] and empty params"""
+        response = self.index.search(None, {})
+        assert isinstance(response, object)
+        assert len(response['hits']) == 20
+
     def test_custom_search(self):
         """Tests search with an simple query and custom parameter (attributesToHighlight)"""
         response = self.index.search(
@@ -54,6 +66,17 @@ def test_custom_search(self):
         assert '_formatted' in response['hits'][0]
         assert 'dragon' in response['hits'][0]['_formatted']['title'].lower()
 
+    def test_custom_search_with_placeholder(self):
+        """Tests search with no query [None] and custom parameter (attributesToHighlight)"""
+        response = self.index.search(
+            None,
+            {
+                'limit': 5
+            }
+        )
+        assert isinstance(response, object)
+        assert len(response['hits']) == 5
+
     def test_custom_search_params_with_wildcard(self):
         """Tests search with '*' in query params"""
         response = self.index.search(