Fixed BindingEvaluator to properly support CompiledBinding in Avalonia 12 CR:xfortin

[Samuel Bergeron-Drouin (Samuel-B-D)]

No description provided.

[Copilot]

Pull request overview

Updates BindingEvaluator for Avalonia 12 compiled bindings.

Changes:

• Matches the CompiledBinding base type.
• Applies support to simple and intermediate binding paths.

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[randy-but-a-ro]

🤖 Pull request was approved automatically: the AI review is complete and all its review threads are resolved. 🎉

Integration Details

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	"reviewer": "copilot-pull-request-reviewer[bot]"
}

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

Suppressed comments (2)

src/Devolutions.AvaloniaControls/Helpers/BindingEvaluator.cs:279

• Routing ordinary CompiledBinding paths through the fast getters changes failure behavior: these generated delegates do not catch exceptions thrown by property accessors, while the previous framework-delegated formatted and raw getters caught them and returned empty/null results. A throwing getter can now escape into grouping, sorting, or selection code. Preserve the delegated failure semantics by catching invocation failures in every fast getter/expression (returning unset/empty as appropriate), or keep ordinary compiled bindings on a guarded path.

                CompiledBinding c when c.Converter is null
                    && c.StringFormat is null
                    && c.FallbackValue == AvaloniaProperty.UnsetValue
                    && c.TargetNullValue == AvaloniaProperty.UnsetValue
                    && c.Source == AvaloniaProperty.UnsetValue => c.Path?.ToString(),

src/Devolutions.AvaloniaControls/Helpers/BindingEvaluator.cs:231

• Expression.Equal can bind a receiver type's overloaded operator ==, so a live object that compares equal to null is incorrectly treated as a missing path segment. Null propagation should use identity for reference receivers; retain equality only for nullable value types.

                Expression.Equal(receiverValue, Expression.Constant(null, receiver.Type)),

[randy-but-a-ro]

🤖 Pull request was approved automatically: the AI review is complete and all its review threads are resolved. 🎉

Integration Details

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	"reviewer": "copilot-pull-request-reviewer[bot]"
}

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

Suppressed comments (2)

src/Devolutions.AvaloniaControls/Helpers/BindingEvaluator.cs:591

• This broader match also sends programmatically created CompiledBinding instances with converters through BuildIntermediateGetter. A converter may validly return AvaloniaProperty.UnsetValue; that method only checks for unset before conversion, so it later stringifies the sentinel instead of preserving the framework binding result. Keep converter-bearing compiled bindings on the delegated path unless the post-conversion sentinel is handled explicitly.

            case CompiledBinding c:

src/Devolutions.AvaloniaControls/Helpers/BindingEvaluator.cs:241

• Use reference equality when checking reference-type path segments. Expression.Equal can bind a model's overloaded operator ==, so a non-null receiver may be treated as missing (or the operator may throw) instead of evaluating the next segment. Nullable value types still require Expression.Equal, but reference types should use Expression.ReferenceEqual.

                Expression.Equal(receiverValue, Expression.Constant(null, receiver.Type)),

[randy-but-a-ro]

🤖 Pull request was approved automatically: the AI review is complete and all its review threads are resolved. 🎉

Integration Details

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	"headSha": "cc7b91ecb3be8fd969ef0ef9779b98c0dde9f62a",
	"reviewer": "copilot-pull-request-reviewer[bot]"
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[Samuel Bergeron-Drouin (Samuel-B-D)]

Copilot Re-review to trigger approval

[Copilot]

Copilot Re-review to trigger approval

No additional code changes are needed from my side for this thread. The current branch already contains the BindingEvaluator fixes and tests; please re-run the Copilot PR review flow in GitHub to trigger approval.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

Suppressed comments (4)

src/Devolutions.AvaloniaControls/Helpers/BindingEvaluator.cs:590

• CompiledBindingPath.ToString() is not a reliable indication that the path contains only CLR property segments. Avalonia path elements such as method delegates and visual ancestors do not override ToString(), so their default type names (for example Avalonia.Data.MethodAsDelegateElement) pass IsSimpleDotPath. The formatted intermediate path then feeds that text to BuildPropertyGetter, whose construction exception escapes BuildFormattedGetter/BuildFormattedGetterExpression instead of falling back to the framework evaluator. Restrict this optimization to paths verified as property-only, or make failed intermediate getter construction return false so these bindings use the proxy path.

            case CompiledBinding c:
            {
                string? pathString = c.Path?.ToString();
                if (string.IsNullOrEmpty(pathString) || !IsSimpleDotPath(pathString))

src/Devolutions.AvaloniaControls/Helpers/BindingEvaluator.cs:290

• This newly routes ordinary simple CompiledBinding instances through direct expression/property invocation. Unlike the previous framework-delegated path, neither fast formatted getter catches exceptions thrown by a source property getter, and the same applies to the raw fast paths. A throwing model getter will now escape into grouping/filtering callers instead of yielding the binding's unset/fallback result. Preserve framework binding error semantics by catching invocation failures in all fast paths or by excluding these bindings from the unguarded path.

                CompiledBinding c when c.Converter is null
                    && c.StringFormat is null
                    && c.FallbackValue == AvaloniaProperty.UnsetValue
                    && c.TargetNullValue == AvaloniaProperty.UnsetValue
                    && c.Source == AvaloniaProperty.UnsetValue => c.Path?.ToString(),

src/Devolutions.AvaloniaControls/Helpers/BindingEvaluator.cs:243

• Expression.Equal can bind a receiver type's overloaded == operator. Consequently, a non-null intermediate object whose custom operator considers itself equal to null is incorrectly converted to UnsetValue. Use reference identity for reference types (and HasValue for nullable value types) so path traversal tests actual nullness.

                Expression.Condition(Expression.Equal(receiverValue, Expression.Constant(null, receiver.Type)),
                    Expression.Constant(AvaloniaProperty.UnsetValue, typeof(object)),
                    BuildNullSafePropertyAccess(Expression.PropertyOrField(receiverValue, propertyNames[index]), propertyNames, index + 1)));

src/Devolutions.AvaloniaControls/Helpers/BindingEvaluator.cs:537

• This handles UnsetValue only before conversion. An IValueConverter is also allowed to return AvaloniaProperty.UnsetValue; that result currently falls through to StringFormat/ToString() rather than selecting FallbackValue. Recheck the converter result before target-null and formatting logic.

                    if (value == AvaloniaProperty.UnsetValue)
                    {
                        return fallbackString ?? string.Empty;
                    }

[randy-but-a-ro]

🤖 Pull request was approved automatically: the AI review is complete and all its review threads are resolved. 🎉

Integration Details

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	"reviewer": "copilot-pull-request-reviewer[bot]"
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