Remove sorting of dictionaries in pretty.printer. #3370

Order of dictionaries is now enforced in Python 3.7 and higher. This means that the original order of dictionaries matters for falsifying examples.

Author: richardscholtens

hypothesis-python/src/hypothesis/vendor/pretty.py

@@ -603,16 +603,7 @@ def inner(obj, p, cycle):
         if cycle:
             return p.text("{...}")
         p.begin_group(1, start)
-        keys = obj.keys()
-        # if dict isn't large enough to be truncated, sort keys before
-        # displaying
-        if not (p.max_seq_length and len(obj) >= p.max_seq_length):
-            try:
-                keys = sorted(keys)
-            except Exception:
-                # Sometimes the keys don't sort.
-                pass
-        for idx, key in p._enumerate(keys):
+        for idx, key in p._enumerate(obj):
             if idx:
                 p.text(",")
                 p.breakable()

hypothesis-python/tests/cover/test_pretty.py

@@ -134,6 +134,7 @@ def test_list():
 def test_dict():
     assert pretty.pretty({}) == "{}"
     assert pretty.pretty({1: 1}) == "{1: 1}"
+    assert pretty.pretty({1: 1, 0: 0}) == "{1: 1, 0: 0}"
 
 
 def test_tuple():