Test both echo and not echo state

ipywidgets/widgets/tests/test_set_state.py

@@ -14,11 +14,17 @@
 
 from .utils import setup, teardown
 
-from ..widget import Widget
+import ipywidgets
+from ipywidgets import Widget
+
+# Everything in this file assumes echo is false
+@pytest.fixture(autouse=True)
+def echo():
+    oldvalue = ipywidgets.widgets.widget.JUPYTER_WIDGETS_ECHO
+    ipywidgets.widgets.widget.JUPYTER_WIDGETS_ECHO = False
+    yield
+    ipywidgets.widgets.widget.JUPYTER_WIDGETS_ECHO = oldvalue
 
-#
-# First some widgets to test on:
-#
 
 # A widget with simple traits (list + tuple to ensure both are handled)
 class SimpleWidget(Widget):
@@ -86,7 +92,7 @@ def test_set_state_simple():
         c=[False, True, False],
     ))
 
-    assert len(w.comm.messages) == 1
+    assert w.comm.messages == []
 
 
 def test_set_state_transformer():
@@ -96,18 +102,11 @@ def test_set_state_transformer():
     ))
     # Since the deserialize step changes the state, this should send an update
     assert w.comm.messages == [((), dict(
-        buffers=[],
-        data=dict(
-            buffer_paths=[],
-            method='echo_update',
-            state=dict(d=[True, False, True]),
-        ))),
-        ((), dict(
         buffers=[],
         data=dict(
             buffer_paths=[],
             method='update',
-            state=dict(d=[False, True, False]),
+            state=dict(d=[False, True, False])
         )))]
 
 
@@ -118,7 +117,7 @@ def test_set_state_data():
         a=True,
         d={'data': data},
     ))
-    assert len(w.comm.messages) == 1
+    assert w.comm.messages == []
 
 
 def test_set_state_data_truncate():
@@ -129,15 +128,15 @@ def test_set_state_data_truncate():
         d={'data': data},
     ))
     # Get message for checking
-    assert len(w.comm.messages) == 2   # ensure we didn't get more than expected
-    msg = w.comm.messages[1]
+    assert len(w.comm.messages) == 1   # ensure we didn't get more than expected
+    msg = w.comm.messages[0]
     # Assert that the data update (truncation) sends an update
     buffers = msg[1].pop('buffers')
     assert msg == ((), dict(
         data=dict(
+            buffer_paths=[['d', 'data']],
             method='update',
-            state=dict(d={}),
-            buffer_paths=[['d', 'data']]
+            state=dict(d={})
         )))
 
     # Sanity:
@@ -157,8 +156,8 @@ def test_set_state_numbers_int():
         i = 3,
         ci = 4,
     ))
-    # Ensure one update message gets produced
-    assert len(w.comm.messages) == 1
+    # Ensure no update message gets produced
+    assert len(w.comm.messages) == 0
 
 
 def test_set_state_numbers_float():
@@ -169,8 +168,8 @@ def test_set_state_numbers_float():
         cf = 2.0,
         ci = 4.0
     ))
-    # Ensure one update message gets produced
-    assert len(w.comm.messages) == 1
+    # Ensure no update message gets produced
+    assert len(w.comm.messages) == 0
 
 
 def test_set_state_float_to_float():
@@ -180,8 +179,8 @@ def test_set_state_float_to_float():
         f = 1.2,
         cf = 2.6,
     ))
-    # Ensure one message gets produced
-    assert len(w.comm.messages) == 1
+    # Ensure no update message gets produced
+    assert len(w.comm.messages) == 0
 
 
 def test_set_state_cint_to_float():
@@ -192,8 +191,8 @@ def test_set_state_cint_to_float():
         ci = 5.6
     ))
     # Ensure an update message gets produced
-    assert len(w.comm.messages) == 2
-    msg = w.comm.messages[1]
+    assert len(w.comm.messages) == 1
+    msg = w.comm.messages[0]
     data = msg[1]['data']
     assert data['method'] == 'update'
     assert data['state'] == {'ci': 5}
@@ -248,136 +247,13 @@ def _propagate_value(self, change):
     # this mimics a value coming from the front end
     widget.set_state({'value': 42})
     assert widget.value == 42
-    assert widget.stop is True
-
-    # we expect no new state to be sent
-    calls = []
-    widget._send.assert_has_calls(calls)
 
-
-def test_hold_sync():
-    # when this widget's value is set to 42, it sets the value to 2, and also sets a different trait value
-    class AnnoyingWidget(Widget):
-        value = Float().tag(sync=True)
-        other = Float().tag(sync=True)
-
-        @observe('value')
-        def _propagate_value(self, change):
-            print('_propagate_value', change.new)
-            if change.new == 42:
-                with self.hold_sync():
-                    self.value = 2
-                    self.other = 11
-
-    widget = AnnoyingWidget(value=1)
-    assert widget.value == 1
-
-    widget._send = mock.MagicMock()
-    # this mimics a value coming from the front end
-    widget.set_state({'value': 42})
-    assert widget.value == 2
-    assert widget.other == 11
-
-    msg = {'method': 'echo_update', 'state': {'value': 42.0}, 'buffer_paths': []}
-    call42 = mock.call(msg, buffers=[])
-
-    msg = {'method': 'update', 'state': {'value': 2.0, 'other': 11.0}, 'buffer_paths': []}
+    # we expect first the {'value': 2.0} state to be send, followed by the {'value': 42.0} state
+    msg = {'method': 'update', 'state': {'value': 2.0}, 'buffer_paths': []}
     call2 = mock.call(msg, buffers=[])
 
-    calls = [call42, call2]
-    widget._send.assert_has_calls(calls)
-
-
-def test_echo():
-    # we always echo values back to the frontend
-    class ValueWidget(Widget):
-        value = Float().tag(sync=True)
-
-    widget = ValueWidget(value=1)
-    assert widget.value == 1
-
-    widget._send = mock.MagicMock()
-    # this mimics a value coming from the front end
-    widget.set_state({'value': 42})
-    assert widget.value == 42
-
-    # we expect this to be echoed
-    msg = {'method': 'echo_update', 'state': {'value': 42.0}, 'buffer_paths': []}
+    msg = {'method': 'update', 'state': {'value': 42.0}, 'buffer_paths': []}
     call42 = mock.call(msg, buffers=[])
 
-    calls = [call42]
-    widget._send.assert_has_calls(calls)
-
-
-
-def test_echo_single():
-    # we always echo multiple changes back in 1 update
-    class ValueWidget(Widget):
-        value = Float().tag(sync=True)
-        square = Float().tag(sync=True)
-        @observe('value')
-        def _square(self, change):
-            self.square = self.value**2
-
-    widget = ValueWidget(value=1)
-    assert widget.value == 1
-
-    widget._send = mock.MagicMock()
-    # this mimics a value coming from the front end
-    widget._handle_msg({
-        'content': {
-            'data': {
-                'method': 'update',
-                'state': {
-                    'value': 8,
-                }
-            }
-        }
-    })
-    assert widget.value == 8
-    assert widget.square == 64
-
-    # we expect this to be echoed
-    # note that only value is echoed, not square
-    msg = {'method': 'echo_update', 'state': {'value': 8.0}, 'buffer_paths': []}
-    call = mock.call(msg, buffers=[])
-
-    msg = {'method': 'update', 'state': {'square': 64}, 'buffer_paths': []}
-    call2 = mock.call(msg, buffers=[])
-
-
-    calls = [call, call2]
+    calls = [call2, call42]
     widget._send.assert_has_calls(calls)
-
-
-def test_no_echo():
-    # in cases where values coming from the frontend are 'heavy', we might want to opt out
-    class ValueWidget(Widget):
-        value = Float().tag(sync=True, echo_update=False)
-
-    widget = ValueWidget(value=1)
-    assert widget.value == 1
-
-    widget._send = mock.MagicMock()
-    # this mimics a value coming from the front end
-    widget._handle_msg({
-        'content': {
-            'data': {
-                'method': 'update',
-                'state': {
-                    'value': 42,
-                }
-            }
-        }
-    })
-    assert widget.value == 42
-
-    # widget._send.assert_not_called(calls)
-    widget._send.assert_not_called()
-
-    # a regular set should sync to the frontend
-    widget.value = 43
-    widget._send.assert_has_calls([mock.call({'method': 'update', 'state': {'value': 43.0}, 'buffer_paths': []}, buffers=[])])
-
-
-