diff --git a/nh2/mock.py b/nh2/mock.py
index 5532188..53ba30e 100644
--- a/nh2/mock.py
+++ b/nh2/mock.py
@@ -75,30 +75,66 @@ async def flush(self):
             await self.s.send(data)
 
 
-def _format(obj, indent=0):
-    return '\n'.join(_do_format(obj, indent)).replace(' \n', '\n')
+def _format(obj):
+    return ''.join(_do_format(obj, 0))
 
 
-def _do_format(obj, indent):
+def _simple(obj):
+    return obj is None or isinstance(obj, (bytes, int, str))
+
+
+def _do_format(obj, indent, name=''):  # pylint: disable=too-many-branches
     prefix = '  ' * indent
-    if isinstance(obj, h2.events.RemoteSettingsChanged):
-        yield '[RemoteSettingsChanged]'
-        yield prefix + ' '.join(f'{setting.setting.name.lower()}={setting.new_value}'
-                                for setting in obj.changed_settings.values())
-    elif isinstance(obj, dict):
-        yield ''
-        for k, v in sorted(obj.items()):
-            k = f'{k}'
+
+    if isinstance(obj, dict):
+        multiline = False
+        items = []
+        for k, v in obj.items():
             if not k.startswith('_'):
-                yield f'{prefix}{k}: {_format(v, indent + 1)}'
+                items.append((k, v))
+                if not multiline and not _simple(v):
+                    multiline = True
+        if not multiline:
+            yield ' ['
+            if name:
+                yield f'{name} '
+            yield ' '.join(f'{k}={repr(v)}' for k, v in items) + ']\n'
+        else:
+            if name:
+                yield f' [{name}]'
+            yield '\n'
+            for k, v in items:
+                yield f'{prefix}{k}:'
+                yield from _do_format(v, indent + 1)
     elif isinstance(obj, list):
-        yield ''
+        multiline = False
         for v in obj:
-            yield f'{prefix}- {_format(v, indent + 1)}'
-    elif obj is None or isinstance(obj, (bytes, int, str, tuple)):
-        yield f'{repr(obj)}'
+            if not _simple(v):
+                multiline = True
+                break
+        if not multiline:
+            yield ' ['
+            if name:
+                yield f'{name} '
+            yield ' '.join(repr(v) for v in obj) + ']\n'
+        else:
+            if name:
+                yield f' [{name}]'
+            yield '\n'
+            for v in obj:
+                yield f'{prefix}-'
+                yield from _do_format(v, indent + 1)
+    elif _simple(obj) or isinstance(obj, tuple):
+        if name:
+            name = f'[{name}] '
+        yield f' {name}{repr(obj)}\n'
     else:
-        yield f'[{obj.__class__.__qualname__}] {_format(obj.__dict__, indent)}'
+        name = obj.__class__.__qualname__
+        if isinstance(obj, h2.events.RemoteSettingsChanged):
+            obj = {chg.setting.name.lower(): chg.new_value for chg in obj.changed_settings.values()}
+        else:
+            obj = obj.__dict__
+        yield from _do_format(obj, indent, name=name)
 
 
 class _DedentingString(str):
diff --git a/nh2/test_mock.py b/nh2/test_mock.py
index e2a570c..e9c08ee 100644
--- a/nh2/test_mock.py
+++ b/nh2/test_mock.py
@@ -15,30 +15,27 @@ async def test_simple():
     mock_server = await nh2.mock.expect_connect('example.com', 443)
     conn = await nh2.connection.Connection('example.com', 443)
     assert await mock_server.read() == """
-      - [RemoteSettingsChanged]
-        header_table_size=4096 enable_push=1 initial_window_size=65535 max_frame_size=16384 enable_connect_protocol=0 max_concurrent_streams=100 max_header_list_size=65536
+      - [RemoteSettingsChanged header_table_size=4096 enable_push=1 initial_window_size=65535 max_frame_size=16384 enable_connect_protocol=0 max_concurrent_streams=100 max_header_list_size=65536]
     """
 
     live_request = await conn.request('POST', '/dummy', json={'a': 1})
     assert await mock_server.read() == """
       - [RequestReceived]
+        stream_id: 1
         headers:
           - (':method', 'POST')
           - (':path', '/dummy')
           - (':authority', 'example.com')
           - (':scheme', 'https')
           - ('content-type', 'application/json; charset=utf-8')
-        priority_updated: None
         stream_ended: None
-        stream_id: 1
+        priority_updated: None
       - [DataReceived]
+        stream_id: 1
         data: b'{"a":1}'
         flow_controlled_length: 7
-        stream_ended: [StreamEnded]
-          stream_id: 1
-        stream_id: 1
-      - [StreamEnded]
-        stream_id: 1
+        stream_ended: [StreamEnded stream_id=1]
+      - [StreamEnded stream_id=1]
     """
 
     mock_server.c.send_headers(1, [(':status', '200')])
@@ -49,15 +46,12 @@ async def test_simple():
     assert response.body == 'dummy response'
     assert await mock_server.read() == """
       - [SettingsAcknowledged]
-        changed_settings:
+        changed_settings: []
     """
 
     await conn.close()
     assert await mock_server.read() == """
-      - [ConnectionTerminated]
-        additional_data: None
-        error_code: <ErrorCodes.NO_ERROR: 0>
-        last_stream_id: 0
+      - [ConnectionTerminated error_code=<ErrorCodes.NO_ERROR: 0> last_stream_id=0 additional_data=None]
     """
     assert await mock_server.read() == """
       SOCKET CLOSED
@@ -79,23 +73,20 @@ async def opaque_workflow():
         future = tg.start_soon(opaque_workflow)
 
         assert await mock_server.read() == """
-          - [RemoteSettingsChanged]
-            header_table_size=4096 enable_push=1 initial_window_size=65535 max_frame_size=16384 enable_connect_protocol=0 max_concurrent_streams=100 max_header_list_size=65536
+          - [RemoteSettingsChanged header_table_size=4096 enable_push=1 initial_window_size=65535 max_frame_size=16384 enable_connect_protocol=0 max_concurrent_streams=100 max_header_list_size=65536]
         """
 
         assert await mock_server.read() == """
           - [RequestReceived]
+            stream_id: 1
             headers:
               - (':method', 'GET')
               - (':path', '/dummy')
               - (':authority', 'example.com')
               - (':scheme', 'https')
+            stream_ended: [StreamEnded stream_id=1]
             priority_updated: None
-            stream_ended: [StreamEnded]
-              stream_id: 1
-            stream_id: 1
-          - [StreamEnded]
-            stream_id: 1
+          - [StreamEnded stream_id=1]
         """
 
         mock_server.c.send_headers(1, [(':status', '200')])