Address PR comments

src/_pytest/_io/pprint.py

@@ -178,7 +178,7 @@ class PrettyPrinter:
             return
         cls = object.__class__
         stream.write(cls.__name__ + "(")
-        self._pprint_dict(object, stream, indent, allowance, context, level)
+        self._format(list(object.items()), stream, indent, allowance, context, level)
         stream.write(")")
 
     _dispatch[_collections.OrderedDict.__repr__] = _pprint_ordered_dict
@@ -373,15 +373,9 @@ class PrettyPrinter:
         item_indent = indent + self._indent_per_level
         delimnl = "\n" + " " * item_indent
 
-        it = iter(items)
-        while True:
-            try:
-                next_ent = next(it)
-            except StopIteration:
-                break
-
+        for item in items:
             write(delimnl)
-            self._format(next_ent, stream, item_indent, 1, context, level)
+            self._format(item, stream, item_indent, 1, context, level)
             write(",")
 
         write("\n" + " " * indent)
@@ -412,10 +406,15 @@ class PrettyPrinter:
     _dispatch[_collections.defaultdict.__repr__] = _pprint_default_dict
 
     def _pprint_counter(self, object, stream, indent, allowance, context, level):
-        stream.write(object.__class__.__name__ + "({")
+        stream.write(object.__class__.__name__ + "(")
+
+        if object:
+            stream.write("{")
             items = object.most_common()
             self._format_dict_items(items, stream, indent, allowance, context, level)
-        stream.write("})")
+            stream.write("}")
+
+        stream.write(")")
 
     _dispatch[_collections.Counter.__repr__] = _pprint_counter
 

testing/io/test_pprint.py

@@ -84,19 +84,28 @@ class DataclassWithTwoItems:
         pytest.param(
             OrderedDict({"one": 1}),
             """
-            OrderedDict({
-                'one': 1,
-            })
+            OrderedDict([
+                (
+                    'one',
+                    1,
+                ),
+            ])
             """,
             id="ordereddict-one-item",
         ),
         pytest.param(
             OrderedDict({"one": 1, "two": 2}),
             """
-            OrderedDict({
-                'one': 1,
-                'two': 2,
-            })
+            OrderedDict([
+                (
+                    'one',
+                    1,
+                ),
+                (
+                    'two',
+                    2,
+                ),
+            ])
             """,
             id="ordereddict-two-items",
         ),
@@ -244,7 +253,7 @@ class DataclassWithTwoItems:
         ),
         pytest.param(
             Counter(),
-            "Counter({})",
+            "Counter()",
             id="counter-empty",
         ),
         pytest.param(
@@ -380,10 +389,16 @@ class DataclassWithTwoItems:
                     'one': 1,
                     'two': 2,
                 }),
-                'ordereddict': OrderedDict({
-                    'one': 1,
-                    'two': 2,
-                }),
+                'ordereddict': OrderedDict([
+                    (
+                        'one',
+                        1,
+                    ),
+                    (
+                        'two',
+                        2,
+                    ),
+                ]),
                 'set': {
                     1,
                     2,

testing/test_assertion.py

@@ -754,6 +754,19 @@ class TestAssert_reprcompare:
             "+     3,",
             "  )",
         ]
+        lines = callequal((1, 2, 3), (1, 20, 3), verbose=2)
+        assert lines == [
+            "(1, 2, 3) == (1, 20, 3)",
+            "At index 1 diff: 2 != 20",
+            "Full diff:",
+            "  (",
+            "      1,",
+            "-     20,",
+            "?      -",
+            "+     2,",
+            "      3,",
+            "  )",
+        ]
 
     def test_set(self) -> None:
         expl = callequal({0, 1}, {0, 2})