Merge pull request #1076 from fabulous-dev/fix-scalar-attributes-data-key-lookup

Fix ScalarAttributes data key lookup

Author: edgarfgp

CHANGELOG.md

@@ -9,6 +9,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 _No unreleased changes_
 
+## [3.0.0-pre4] - 2024-04-16
+
+### Changed
+- Find the component data key in ScalarAttributes by @edgarfgp (https://github.com/fabulous-dev/Fabulous/pull/1076)
+
 ## [3.0.0-pre3] - 2024-04-12
 
 ### Changed
@@ -125,7 +130,8 @@ _No unreleased changes_
 ### Changed
 - Fabulous.XamarinForms & Fabulous.MauiControls have been moved been out of the Fabulous repository. Find them in their own repositories: [https://github.com/fabulous-dev/Fabulous.XamarinForms](https://github.com/fabulous-dev/Fabulous.XamarinForms) / [https://github.com/fabulous-dev/Fabulous.MauiControls](https://github.com/fabulous-dev/Fabulous.MauiControls)
 
-[unreleased]: https://github.com/fabulous-dev/Fabulous/compare/3.0.0-pre3...HEAD
+[unreleased]: https://github.com/fabulous-dev/Fabulous/compare/3.0.0-pre4...HEAD
+[3.0.0-pre4]: https://github.com/fabulous-dev/Fabulous/releases/tag/3.0.0-pre4
 [3.0.0-pre3]: https://github.com/fabulous-dev/Fabulous/releases/tag/3.0.0-pre3
 [3.0.0-pre2]: https://github.com/fabulous-dev/Fabulous/releases/tag/3.0.0-pre2
 [3.0.0-pre1]: https://github.com/fabulous-dev/Fabulous/releases/tag/3.0.0-pre1

src/Fabulous/MvuComponent.fs

@@ -99,12 +99,25 @@ module MvuComponent =
     let canReuseMvuComponent (prev: Widget) (curr: Widget) =
         let prevData =
             match prev.ScalarAttributes with
-            | ValueSome attrs when attrs.Length > 0 -> attrs[0].Value :?> MvuComponentData
+            | ValueSome attrs ->
+                let scalarAttrsOpt =
+                    attrs |> Array.tryFind(fun scalarAttr -> scalarAttr.Key = Data.Key)
+
+                match scalarAttrsOpt with
+                | None -> failwithf "Component widget must have a body"
+                | Some value -> value.Value :?> MvuComponentData
+
             | _ -> failwith "Component widget must have a body"
 
         let currData =
             match curr.ScalarAttributes with
-            | ValueSome attrs when attrs.Length > 0 -> attrs[0].Value :?> MvuComponentData
+            | ValueSome attrs ->
+                let scalarAttrsOpt =
+                    attrs |> Array.tryFind(fun scalarAttr -> scalarAttr.Key = Data.Key)
+
+                match scalarAttrsOpt with
+                | None -> failwithf "Component widget must have a body"
+                | Some value -> value.Value :?> MvuComponentData
             | _ -> failwith "Component widget must have a body"
 
         // NOTE: Somehow using = here crashes the app and prevents debugging...