* Fix TextBox validation error persisting when reverting to same valid value
When a TwoWay binding with validation had an error and the user set the
target back to the same value that was last successfully written to the
source, WriteTargetValueToSource() would bail out early because the
target value matched LeafNode.Value. This prevented WriteValueToSource()
from being called, so the validation error was never cleared.
Add an ErrorType check to the condition in WriteTargetValueToSource() so
that the write-through still happens when there is a pending validation
error, matching the pattern already used in WriteValueToSource() at
line 310.
Fixes#20534https://claude.ai/code/session_01LTinLuE1bsNKaLPuDSNuuw
* Add test for validation error clearing when reverting to same valid value
Reproduces the scenario from #20534 where a TwoWay binding with a
setter that throws on invalid values fails to clear the validation error
when the target is set back to the same value that was last successfully
written to the source.
https://claude.ai/code/session_01LTinLuE1bsNKaLPuDSNuuw
* Remove redundant checks in WriteTargetValueToSource()
Make LeafNode property nullable and return null when the binding expression
has no nodes (e.g., when using a constant source with a converter but no path).
This fixes an ArgumentOutOfRangeException that occurred when accessing
LeafNode or Description properties on such bindings.
Fixes#20441
Co-authored-by: Claude Sonnet 4.5 <noreply@anthropic.com>
* Update ncrunch config.
* Fix test naming.
* Add BindingExpressionGrammar tests.
We only had tests for the error states, and that was named incorrectly.
* Parse null-conditionals in bindings.
* Initial impl of null conditionals in binding path.
Fixes#17029.
* Ensure that nothing is logged.
* Make "?." work when binding to methods.
* Don't add a new public API.
And add a comment reminding us to make this class internal for 12.0.
* Use existing method.
* Add failing tests for OneTime and null data context bindings
* Made OneTime bindings update on DataContext changes
Also allows null as a valid value for bindings without path
* Remove now obsolete test
* Added failing test for #15201.
* Handle nested BindingNotifications.
When #13970 was written, [a check](https://github.com/AvaloniaUI/Avalonia/pull/13970/files#diff-cfb25a491b9452e1815aa2c0d71465aaf81e99792a88a04a1a2ed572fd1930ffR60) was added to ensure that nested `BindingNotification`s didn't happen, and the refactor was written with the assumption that they wouldn't happen.
The problem is that they _do_ happen: when a source object implements both `INotifyDataErrorInfo` and had data annotations, then the nested data validation plugins would each wrap the value coming from the previous plugin in a new `BindingNotification`, resulting in nested `BindingNotifications`.
This adds support for nested binding notifications back in - even though IMO nesting binding notifications is a bug, if we're doing it and we previously supported it then we should continue to support it.
Fixes#15201
* Added failing tests for #15081.
* Provide target property in BindingExpression ctor.
Usually it is not necessary to provide the target property when creating a `BindingExpression` because the property will be assigned when the binding expression is attached to the target in `BindingExpressionBase.Attach`.
This is however one case where `Attach` is not called: when the obsolete `binding.Initiate` method is called and then an observable is read from the `InstancedBinding` without the binding actually being attached to the target object. In this case, prior to the binding refactor in #13970 the value produced by the observable was still converted to the target type. After #13970, because the target property (and hence the target type) is not yet set, the conversion is to the target type is no longer done.
`DataGrid` uses this obsolete method when editing cells, causing #15081. Ideally we'd fix that in `DataGrid` but I'm not happy making this change so close to 11.1, so instead fix this use-case to behave as before.
Fixes#15081
* Added more OneWayToSource tests.
One of whom is failing.
* Don't public value for OneWayToSource bindings.
Looks to have been a brainfart. This allows `OneWayToSource` bindings to read-only properties.
* Update ncrunch config.
* WIP: Benchmarks
* Initial refactor of binding infrastructure.
- `ExpressionObserver` has been removed and its functionality merged with `BindingExpression`
- `BindingExpression` handles all types of `BindingMode` itself; doesn't require `BindingOperations.Apply` to set up a separate observable for `TwoWay/`OneWayToSource` bindings
- This allows us to fix some long-standing issues with `OneWayToSource` bindings
- Expression nodes have been refactored
- No longer split between `Avalonia.Base` and `Avalonia.Markup`
- Categorize them according to whether they use reflection or not
A few tests are failing around binding warnings: this is because the next step here is to fix binding warnings.
* Make default binding Source = UnsetProperty.
Null is a theoretically valid value for `Source`; setting it to null shouldn't mean "use the data context".
* Move logging to BindingExpression.
As `BindingExpression` now has enough information to decide when it's appropriate to log an error/warning or not.
Fixes#5762Fixes#9422
* Add compatibility hack for older compiled bindings.
Previously, `CompiledBindingPathBuilder` didn't have a `TemplatedParent` method and instead the XAML compiler rewrite templated parent bindings to be a `$self.TemplateParent` property binding. resulting in extraneous logs.
Add a constructor with an `apiVersion` to `CompiledBindingPathBuilder` which will be used by newer versions of the XAML compiler, and if a usage is detected using an `apiVersion` of 0, then upgrade `$self.TemplatedParent` to use a `TemplatedParentPathElement`.
* Log errors from property accessors.
* Don't log errors for named control bindings...
...on elements which aren't yet rooted.
* Log errors for failed conversions.
* Use consistent wording for binding warnings.
"Could not convert" instead of "Cannot convert".
* Log warnings for converter exceptions.
* Don't convert new TargetTypeConverters each time.
* Added failing test for implicit conversion.
* Support cast operators in compiled bindings.
A bit of a hack as we'd ideally not be using reflection when using compiled bindings.
* This shouldn't be a public API.
Should only be used for tests.
* Make enum/int conversion work.
* Check for SetValue equality after conversion.
And also use "identity equals" where value types and strings use `object.Equals` and reference types use `object.ReferenceEquals`.
* Added ConverterCulture back to bindings.
* Fix merge error.
Removed deleted files from csproj that were re-added due to indentation changes.
* Use BindingExpression directly in ValueStoe.
* Introduce BindingExpressionBase.
And `UntypedBindingExpressionBase`.
* Make TemplateBinding a BindingExpression.
* Make DynamicResource use a BindingExpression.
* WIP: Start exposing a BindingExpression API.
* Finish exposing a BindingExpression API.
* Fix OneTimeBinding.
* Remove unneeded classes/methods.
* Don't call obsolete API.
* Make BindingExpressionBase the public API.
This matches WPF's API.
* Added BindingExpressionBase.UpdateTarget.
* Initial implementation of UpdateSourceTrigger.
* Don't use weak references for values.
If they're boxed values, they can get collected.
* No need for virtual/generic methods here now.
* Reintroduce support for binding anchors.
Turns out these were needed by animations, just our animation system has no unit tests so I missed that fact earlier. Add a basic animation unit test that fails without anchor support, and add binding anchors back in. Currently a private API as I suspect this feature shouldn't be needed outside the framework.
* Include new property in clone.
And add real-life example of `UpdateSourceTrigger=LostFocus` to BindingDemo.
* Fix merge error.
* Updated BindingExpression tests.
- Make them run for both compiled and reflection bindings (found a bunch of tests that fail with compiled bindings)
- Make them not depend on converting the `BindingExpression` to an observable and instead test the end result of the binding on an `AvaloniaObject`
* Fix compiled binding indexer tests.
* Use data validation plugins in PropertyAccessorNode.
Added a warning suppression for now: we may need a separate `DataValidators` list for AOT-friendly plugins.
* Don't separate plugins by reflection.
`DataAnnotationsValidationPlugin` is public and so it can't be moved. No point in moving the others if this one will be in the wrong place.
* Remove unneeded methods.
* Make reflection binding tests use a string.
Convert the `System.Linq.Expression` to a string and then use this, as reflection bindings will always be instanced with a string path.
* Added TODO12 plan for IBinding2.
* Use more specific exception.
* Fix nits from code review.
* Make expression nodes sealed where possible.
* Unsubscribe on Stop, don't re-subscribe.
D'oh.
* Tweak ExpressionNode lists.
Saves a few K in benchmarks and it's a cleaner API.
* Add a pooled option in BindingExpressionGrammar.
Micro-optimization.
* Avoid allocations when enumerating binding plugins.
* Add IBinding2 support to observable bind overloads.
In the case of `TemplateBinding`, the `IObservable<object?>` bind overload is selected by C#. Add an explicit check for an `IBinding2` here to use the more performant code-path.
* Remove disposed binding from ImmediateBindingFrame.
* Added TemplateBinding benchmarks.
* Remove duplicate items.
Seems to have been caused by a merge error.
* Fix exception when closing color picker.
And add tests.
* Don't skip converter when binding to self.
* Don't pass UnsetValue to converters.
This follows WPF behavior.
* Log element name if present.
More useful than just logging the control hash code.
* Respect binding priority.
* Throw on mismatched binding priorities.
We don't want to respect the binding priority in this case as it breaks `TemplateBindings` when the default `LocalValue` priority is passed. Instead make sure that the priority parameter matches that of the expression.
This reverts commit a72765d705.
* Convert to target type in TemplateBinding.
* Short-circuit target type conversion for same types.
* Merge core libraries.
Everything below `Avalonia.Controls` into `Avalonia.Base`.
* Move new files to correct place.
* Removed unused dirs/projects,
* Removed outdated references from theme assemblies.
* Merge unit tests to match new assembly layout.
* Fixup test namespaces.
* Make directory match namespace.
* Move files to match namespace.
* Move files to match namespace.
* Fix up incorrect namespace.
`Avalonia.Visuals.Media.Imaging` -> `Avalonia.Media.Imaging`.
* Fix resource URL.
* Removed outdated dependencies.
* Added missing project reference.
* Update test namespaces.
* Fix merge error.
* Fix merge errors.
* Fix bad merge in WindowsInteropTest.csproj.
* Fix up merge errors in csprojs.
* Remove merged tests from nuke.
* Fix up namespace.
* Fix compile error.
* Fix failing tests.
Now that more unit tests are present in Avalonia.Base.UnitTests, general `AvaloniaObject` properties are getting registered. Ignore those.
Co-authored-by: Jumar Macato <16554748+jmacato@users.noreply.github.com>
`ExpressionNode`s were always single-subscriber and making them use `IObservable<>` meant that we had to have extra allocations in order to return `IDisposable`s. Instead of using `IObservable` use a simpler `Subscribe`/`Unsubscribe` pattern. This saves a bunch more memory.
Evan
Steven Kirk
Ondřej Sušovský
Julien Lebosquain
Tom Edwards
Max Katz
Simon Cropp
Steven Kirk
Giuseppe Lippolis
Nikita Tsukanov
Dariusz Komosiński
Kieran Devlin
José Pedro
all.owing
Jeremy Koritzinsky