Added error checking for unsupported minimum_should_match values (#1774…

…) (#1794)

(cherry picked from commit c650b62)

Co-authored-by: Miguel Grinberg <miguel.grinberg@gmail.com>

elasticsearch_dsl/query.py

@@ -208,8 +208,13 @@ def __and__(self, other):
                 del q._params["minimum_should_match"]
 
             for qx in (self, other):
-                # TODO: percentages will fail here
                 min_should_match = qx._min_should_match
+                # TODO: percentages or negative numbers will fail here
+                # for now we report an error
+                if not isinstance(min_should_match, int) or min_should_match < 0:
+                    raise ValueError(
+                        "Can only combine queries with positive integer values for minimum_should_match"
+                    )
                 # all subqueries are required
                 if len(qx.should) <= min_should_match:
                     q.must.extend(qx.should)

tests/test_query.py

@@ -278,6 +278,28 @@ def test_bool_and_bool_with_min_should_match():
     assert query.Q("bool", must=[qt1, qt2]) == q1 & q2
 
 
+def test_negative_min_should_match():
+    qt1, qt2 = query.Match(f=1), query.Match(f=2)
+    q1 = query.Q("bool", minimum_should_match=-2, should=[qt1])
+    q2 = query.Q("bool", minimum_should_match=1, should=[qt2])
+
+    with raises(ValueError):
+        q1 & q2
+    with raises(ValueError):
+        q2 & q1
+
+
+def test_percentage_min_should_match():
+    qt1, qt2 = query.Match(f=1), query.Match(f=2)
+    q1 = query.Q("bool", minimum_should_match="50%", should=[qt1])
+    q2 = query.Q("bool", minimum_should_match=1, should=[qt2])
+
+    with raises(ValueError):
+        q1 & q2
+    with raises(ValueError):
+        q2 & q1
+
+
 def test_inverted_query_becomes_bool_with_must_not():
     q = query.Match(f=42)