Merge pull request #479 from frmdstryr/d-change-types

Add new declarative @observe which ignores 'create' events by default

enaml/core/declarative.py

@@ -5,13 +5,31 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Event, Typed, Str
+from atom.api import ChangeType, Event, Typed, Str, observe as default_observe
 from atom.datastructures.api import sortedmap
 
 from .declarative_meta import DeclarativeMeta
 from .expression_engine import ExpressionEngine
 from .object import Object, flag_generator, flag_property
 
+#: Declarative observe ignores create events
+OBSERVE_CHANGE_TYPES = ChangeType.ANY & ~ChangeType.CREATE
+
+
+def observe(*names, change_types=OBSERVE_CHANGE_TYPES):
+    """ An observe decorator which ignores the created event by default.
+
+    Parameters
+    ----------
+    *names
+        The str names of the attributes to observe on the object.
+        These must be of the form 'foo' or 'foo.bar'.
+    change_types
+        The flag specifying the type of changes to observe.
+
+    """
+    return default_observe(*names, change_types=change_types)
+
 
 def d_(member, readable=True, writable=True, final=True):
     """ Mark an Atom member as bindable from Enaml syntax.

enaml/core/declarative_meta.py

@@ -5,7 +5,12 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Atom, AtomMeta, DefaultValue, Member, Typed
+from atom.api import Atom, AtomMeta, ChangeType, DefaultValue, Member, Typed
+
+# The declarative engine only updates for these types of changes
+D_CHANGE_TYPES = (
+    ChangeType.UPDATE | ChangeType.PROPERTY | ChangeType.EVENT | ChangeType.DELETE
+)
 
 
 class DeclarativeDefaultHandler(Atom):
@@ -60,12 +65,11 @@ def declarative_change_handler(change):
 
     """
     # TODO think about whether this is the right place to filter on change_t
-    change_t = change['type']
-    if change_t == 'update' or change_t == 'event' or change_t == 'property':
-        owner = change['object']
-        engine = owner._d_engine
-        if engine is not None:
-            engine.write(owner, change['name'], change)
+    # NOTE: Filtering on change['type'] is done by atom
+    owner = change['object']
+    engine = owner._d_engine
+    if engine is not None:
+        engine.write(owner, change['name'], change)
 
 
 def patch_d_member(member):
@@ -88,7 +92,7 @@ def patch_d_member(member):
         new_mode = DefaultValue.CallObject_ObjectName
         member.set_default_value_mode(new_mode, handler)
     if metadata['d_readable']:
-        member.add_static_observer(declarative_change_handler)
+        member.add_static_observer(declarative_change_handler, D_CHANGE_TYPES)
 
 
 class DeclarativeMeta(AtomMeta):

enaml/core/dynamic_template.py

@@ -5,12 +5,12 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Dict, List, Str, Tuple, Typed, observe
+from atom.api import Dict, List, Str, Tuple, Typed
 
 from enaml.application import ScheduledTask, schedule
 from enaml.objectdict import ObjectDict
 
-from .declarative import Declarative, d_
+from .declarative import Declarative, d_, observe
 from .template import Template
 
 

enaml/scintilla/scintilla.py

@@ -9,10 +9,10 @@
 
 from atom.api import (
     Atom, Int, Constant, Enum, Event, Typed, List, ForwardTyped, Tuple,
-    Str, observe, set_default
+    Str, set_default
 )
 from enaml.image import Image
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 from enaml.widgets.control import Control, ProxyControl
 
 

enaml/styling.py

@@ -10,10 +10,10 @@
 """
 from collections import defaultdict
 
-from atom.api import Atom, Str, Typed, observe
+from atom.api import Atom, Str, Typed
 
 from enaml.application import Application, deferred_call
-from enaml.core.declarative import Declarative, d_
+from enaml.core.declarative import Declarative, d_, observe
 
 
 class Setter(Declarative):

enaml/widgets/abstract_button.py

@@ -6,10 +6,10 @@
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
 from atom.api import (
-    Bool, Str, Coerced, Event, Typed, ForwardTyped, observe, set_default
+    Bool, Str, Coerced, Event, Typed, ForwardTyped, set_default
 )
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 from enaml.icon import Icon
 from enaml.layout.geometry import Size
 

enaml/widgets/action.py

@@ -5,9 +5,9 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Typed, ForwardTyped, Str, Bool, Event, observe
+from atom.api import Typed, ForwardTyped, Str, Bool, Event
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 from enaml.icon import Icon
 
 from .toolkit_object import ToolkitObject, ProxyToolkitObject

enaml/widgets/action_group.py

@@ -5,9 +5,9 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Bool, Typed, ForwardTyped, observe
+from atom.api import Bool, Typed, ForwardTyped
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .action import Action
 from .toolkit_object import ToolkitObject, ProxyToolkitObject

enaml/widgets/bounded_date.py

@@ -7,9 +7,9 @@
 #------------------------------------------------------------------------------
 from datetime import date as pydate
 
-from atom.api import Typed, ForwardTyped, observe
+from atom.api import Typed, ForwardTyped
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .control import Control, ProxyControl
 

enaml/widgets/bounded_datetime.py

@@ -7,9 +7,9 @@
 #------------------------------------------------------------------------------
 from datetime import datetime as pydatetime
 
-from atom.api import Typed, ForwardTyped, observe
+from atom.api import Typed, ForwardTyped
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .control import Control, ProxyControl
 

enaml/widgets/bounded_time.py

@@ -7,9 +7,9 @@
 #------------------------------------------------------------------------------
 from datetime import datetime, time as pytime
 
-from atom.api import Typed, ForwardTyped, observe
+from atom.api import Typed, ForwardTyped
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .control import Control, ProxyControl
 

enaml/widgets/button_group.py

@@ -5,9 +5,9 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Bool, ForwardTyped, Typed, observe
+from atom.api import Bool, ForwardTyped, Typed
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .toolkit_object import ToolkitObject, ProxyToolkitObject
 

enaml/widgets/color_dialog.py

@@ -5,11 +5,11 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Bool, Typed, ForwardTyped, observe
+from atom.api import Bool, Typed, ForwardTyped
 
 from enaml.application import Application
 from enaml.colors import ColorMember, Color
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .toolkit_dialog import ToolkitDialog, ProxyToolkitDialog
 

enaml/widgets/combo_box.py

@@ -6,11 +6,10 @@
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
 from atom.api import (
-    Bool, List, Int, Property, Str, Typed, ForwardTyped, set_default,
-    observe
+    Bool, List, Int, Property, Str, Typed, ForwardTyped, set_default
 )
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .control import Control, ProxyControl
 

enaml/widgets/constraints_widget.py

@@ -5,9 +5,9 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import List, ForwardTyped, Typed, observe
+from atom.api import List, ForwardTyped, Typed
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 from enaml.layout.constrainable import ConstrainableMixin, PolicyEnum
 
 from .widget import Widget, ProxyWidget

enaml/widgets/container.py

@@ -5,9 +5,9 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Bool, Coerced, ForwardTyped, Typed, observe, set_default
+from atom.api import Bool, Coerced, ForwardTyped, Typed, set_default
 
-from enaml.core.declarative import d_, d_func
+from enaml.core.declarative import d_, d_func, observe
 from enaml.layout.constrainable import ContentsConstrainableMixin
 from enaml.layout.geometry import Box
 from enaml.layout.layout_helpers import vbox

enaml/widgets/date_selector.py

@@ -5,9 +5,9 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Bool, Str, Typed, ForwardTyped, observe, set_default
+from atom.api import Bool, Str, Typed, ForwardTyped, set_default
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .bounded_date import BoundedDate, ProxyBoundedDate
 

enaml/widgets/datetime_selector.py

@@ -5,9 +5,9 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Bool, Str, Typed, ForwardTyped, observe, set_default
+from atom.api import Bool, Str, Typed, ForwardTyped, set_default
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .bounded_datetime import BoundedDatetime, ProxyBoundedDatetime
 

enaml/widgets/dock_area.py

@@ -8,11 +8,10 @@
 from contextlib import contextmanager
 
 from atom.api import (
-    Bool, Coerced, Enum, Typed, ForwardTyped, Str, Event, observe,
-    set_default
+    Bool, Coerced, Enum, Typed, ForwardTyped, Str, Event, set_default
 )
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 from enaml.layout.dock_layout import DockLayout, DockLayoutOp
 from enaml.styling import StyleSheet
 

enaml/widgets/dock_item.py

@@ -5,12 +5,10 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import (
-    Coerced, Event, Str, Bool, Range, Typed, ForwardTyped, observe
-)
+from atom.api import Coerced, Event, Str, Bool, Range, Typed, ForwardTyped
 
 from enaml.application import deferred_call
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 from enaml.icon import Icon
 from enaml.layout.geometry import Size
 

enaml/widgets/dock_pane.py

@@ -5,11 +5,9 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import (
-    List, Enum, Str, Bool, Event, Typed, ForwardTyped, observe
-)
+from atom.api import List, Enum, Str, Bool, Event, Typed, ForwardTyped
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .container import Container
 from .widget import Widget, ProxyWidget

enaml/widgets/dual_slider.py

@@ -5,9 +5,9 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Bool, Enum, Int, Range, Typed, ForwardTyped, observe
+from atom.api import Bool, Enum, Int, Range, Typed, ForwardTyped
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .control import Control, ProxyControl
 

enaml/widgets/field.py

@@ -6,10 +6,10 @@
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
 from atom.api import (
-    Bool, Int, Str, Enum, List, Typed, ForwardTyped, observe, set_default
+    Bool, Int, Str, Enum, List, Typed, ForwardTyped, set_default
 )
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 from enaml.validator import Validator
 
 from .control import Control, ProxyControl

enaml/widgets/file_dialog_ex.py

@@ -5,9 +5,9 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Bool, Enum, List, Str, Typed, ForwardTyped, observe
+from atom.api import Bool, Enum, List, Str, Typed, ForwardTyped
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .toolkit_dialog import ToolkitDialog, ProxyToolkitDialog
 

enaml/widgets/flow_area.py

@@ -5,11 +5,9 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import (
-    Enum, Range, Coerced, Typed, ForwardTyped, observe, set_default
-)
+from atom.api import Enum, Range, Coerced, Typed, ForwardTyped, set_default
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 from enaml.layout.geometry import Box
 
 from .frame import Frame, ProxyFrame, Border

enaml/widgets/flow_item.py

@@ -5,9 +5,9 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Enum, Range, Coerced, Typed, ForwardTyped, observe
+from atom.api import Enum, Range, Coerced, Typed, ForwardTyped
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 from enaml.layout.geometry import Size
 
 from .container import Container

enaml/widgets/form.py

@@ -5,12 +5,12 @@
 #
 # The full license is in the file LICENSE, distributed with this software.
 #------------------------------------------------------------------------------
-from atom.api import Int, observe
+from atom.api import Int
 
 from enaml.layout.constrainable import ConstraintMember
 from enaml.layout.layout_helpers import align, vertical, horizontal, spacer
 
-from enaml.core.declarative import d_
+from enaml.core.declarative import d_, observe
 
 from .container import Container