pub struct Harness<'a, T> { /* private fields */ }Expand description
A type that tries very hard to provide a comforting and safe environment for widgets who are trying to find their way.
You create a Harness with some widget and its initial data; then you
can send events to that widget and verify that expected conditions are met.
Harness tries to act like the normal Druid environment; for instance, it will
attempt to dispatch any Commands that are sent during event handling, and
it will call update automatically after an event.
That said, it is missing a bunch of logic that would normally be handled
in AppState: for instance it does not clear the needs_inval and
children_changed flags on the window after an update.
In addition, layout and paint are not called automatically. This is
because paint is triggered by druid-shell, and there is no druid-shell here;
if you want those functions run you will need to call them yourself.
Also, timers don’t work. ¯_(ツ)_/¯
Implementations§
§impl<T> Harness<'_, T>where
T: Data,
impl<T> Harness<'_, T>where T: Data,
pub fn create_simple(
data: T,
root: impl Widget<T> + 'static,
harness_closure: impl FnMut(&mut Harness<'_, T>)
)
pub fn create_simple( data: T, root: impl Widget<T> + 'static, harness_closure: impl FnMut(&mut Harness<'_, T>) )
Create a new Harness with the given data and a root widget,
and provide that harness to the passed in function.
For lifetime reasons™, we cannot just make a harness. It’s complicated. I tried my best.
This function is a subset of create_with_render
pub fn create_with_render(
data: T,
root: impl Widget<T> + 'static,
window_size: Size,
harness_closure: impl FnMut(&mut Harness<'_, T>),
render_context_closure: impl FnMut(TargetGuard<'_>)
)
pub fn create_with_render( data: T, root: impl Widget<T> + 'static, window_size: Size, harness_closure: impl FnMut(&mut Harness<'_, T>), render_context_closure: impl FnMut(TargetGuard<'_>) )
Create a new Harness with the given data and a root widget,
and provide that harness to the harness_closure callback and then the
render_context to the render_context_closure callback.
For lifetime reasons™, we cannot just make a harness. It’s complicated. I tried my best.
The with_render version of create also has a callback that can be used
to save or inspect the painted widget
Usage
The create functions are used to test a widget. The function takes a root widget
and a data structure and uses them to create a Harness. The Harness can then be interacted
with via the harness_closure callback. The final render of
the widget can be inspected with the render_context_closure callback.
Arguments
-
data- A structure that matches the type of the widget and that will be passed to theharness_closurecallback via theHarnessstructure. -
root- The widget under test -
shape- The shape of the render_context in theHarnessstructure -
harness_closure- A closure used to interact with the widget under test through theHarnessstructure. -
render_context_closure- A closure used to inspect the final render_context via theTargetGuardstructure.
pub fn set_initial_size(&mut self, size: Size)
pub fn set_initial_size(&mut self, size: Size)
Set the size without sending a resize event; intended to be used
before calling send_initial_events
pub fn window(&self) -> &Window<T>
pub fn window_mut(&mut self) -> &mut Window<T>
pub fn data(&self) -> &T
pub fn get_state(&mut self, widget: WidgetId) -> WidgetState
pub fn get_state(&mut self, widget: WidgetId) -> WidgetState
Retrieve a copy of this widget’s WidgetState, or die trying.
pub fn try_get_state(&mut self, widget: WidgetId) -> Option<WidgetState>
pub fn try_get_state(&mut self, widget: WidgetId) -> Option<WidgetState>
Attempt to retrieve a copy of this widget’s WidgetState.
pub fn get_root_debug_state(&self) -> DebugState
pub fn get_root_debug_state(&self) -> DebugState
Retrieve a copy of the root widget’s DebugState (and by recursion, all others)
pub fn get_debug_state(&mut self, widget_id: WidgetId) -> DebugState
pub fn get_debug_state(&mut self, widget_id: WidgetId) -> DebugState
Retrieve a copy of this widget’s DebugState, or die trying.
pub fn try_get_debug_state(&mut self, widget_id: WidgetId) -> Option<DebugState>
pub fn try_get_debug_state(&mut self, widget_id: WidgetId) -> Option<DebugState>
Attempt to retrieve a copy of this widget’s DebugState.
pub fn inspect_state(&mut self, f: impl Fn(&WidgetState) + 'static)
pub fn inspect_state(&mut self, f: impl Fn(&WidgetState) + 'static)
Inspect the WidgetState of each widget in the tree.
The provided closure will be called on each widget.
pub fn submit_command(&mut self, cmd: impl Into<Command>)
pub fn submit_command(&mut self, cmd: impl Into<Command>)
Send a command to a target.
pub fn send_initial_events(&mut self)
pub fn send_initial_events(&mut self)
Send the events that would normally be sent when the app starts.
pub fn event(&mut self, event: Event)
pub fn event(&mut self, event: Event)
Send an event to the widget.
If this event triggers lifecycle events, they will also be dispatched,
as will any resulting commands. This will also trigger update.
Commands dispatched during update will not be sent?
pub fn just_layout(&mut self)
pub fn just_layout(&mut self)
Only do a layout pass, without painting
pub fn paint_invalid(&mut self)
pub fn paint_invalid(&mut self)
Paints just the part of the window that was invalidated by calls to request_paint or
request_paint_rect.
Also resets the invalid region.
pub fn paint(&mut self)
pub fn paint(&mut self)
Paints the entire window and resets the invalid region.