Support for multiple environment values on single widget

Author: TimLariviere

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-pre12] - 2024-11-20
+
+### Added
+- Add support for multiple environment modifiers on the same widget by @TimLariviere
+
 ## [3.0.0-pre11] - 2024-11-16
 
 ### Changed
@@ -172,7 +177,8 @@ _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-pre11...HEAD
+[unreleased]: https://github.com/fabulous-dev/Fabulous/compare/3.0.0-pre12...HEAD
+[3.0.0-pre12]: https://github.com/fabulous-dev/Fabulous/releases/tag/3.0.0-pre12
 [3.0.0-pre11]: https://github.com/fabulous-dev/Fabulous/releases/tag/3.0.0-pre11
 [3.0.0-pre10]: https://github.com/fabulous-dev/Fabulous/releases/tag/3.0.0-pre10
 [3.0.0-pre9]: https://github.com/fabulous-dev/Fabulous/releases/tag/3.0.0-pre9

global.json

@@ -0,0 +1,5 @@
+{
+"sdk": {
+    "version": "8.0.404"
+}
+  }

src/Fabulous.Tests/APISketchTests/APISketchTests.fs

@@ -643,7 +643,7 @@ module Issue104 =
     let ControlWidgetKey = Widgets.register<TestButton>()
 
     let Control () =
-        WidgetBuilder<'msg, TestButtonMarker>(ControlWidgetKey, AttributesBundle(StackList.StackList.empty(), ValueNone, ValueNone))
+        WidgetBuilder<'msg, TestButtonMarker>(ControlWidgetKey)
 
     [<System.Runtime.CompilerServices.Extension>]
     type WidgetExtensions() =

src/Fabulous.Tests/ViewTests.fs

@@ -17,16 +17,15 @@ type ``View helper functions tests``() =
     /// Test: https://github.com/fabulous-dev/Fabulous/pull/1037
     [<Test>]
     member _.``Mapping a WidgetBuilder with Unit Msg to another Msg is supported``() =
-        let widgetBuilder =
-            WidgetBuilder<unit, ITestControl>(TestControl.WidgetKey, AttributesBundle(StackList.empty(), ValueNone, ValueNone))
+        let widgetBuilder = WidgetBuilder<unit, ITestControl>(TestControl.WidgetKey)
 
         let mapMsg (oldMsg: unit) = ChildMsg oldMsg
 
         let mappedWidgetBuilder = View.map mapMsg widgetBuilder
 
         Assert.AreEqual(widgetBuilder.Key, mappedWidgetBuilder.Key)
 
-        let struct (scalars, _, _) = mappedWidgetBuilder.Attributes
+        let struct (scalars, _, _, _) = mappedWidgetBuilder.Attributes
         let scalars = StackList.toArray &scalars
 
         Assert.AreEqual(1, scalars.Length)

src/Fabulous/AttributeDefinitions.fs

@@ -160,7 +160,6 @@ module AttributeDefinitionStore =
     let private _scalars = ResizeArray<ScalarAttributeData>()
     let private _smallScalars = ResizeArray<SmallScalarAttributeData>()
     let private _widgets = ResizeArray<WidgetAttributeData>()
-
     let private _widgetCollections = ResizeArray<WidgetCollectionAttributeData>()
 
     let registerSmallScalar (data: SmallScalarAttributeData) : ScalarAttributeKey =

src/Fabulous/Builders.fs

@@ -7,31 +7,39 @@ open Fabulous.StackAllocatedCollections
 open Fabulous.StackAllocatedCollections.StackList
 open Microsoft.FSharp.Core
 
-type AttributesBundle = (struct (StackList<ScalarAttribute> * WidgetAttribute[] voption * WidgetCollectionAttribute[] voption))
+type AttributesBundle = (struct (StackList<ScalarAttribute> * WidgetAttribute[] voption * WidgetCollectionAttribute[] voption * EnvironmentAttribute[] voption))
 
 [<Struct; NoComparison; NoEquality>]
 type WidgetBuilder<'msg, 'marker when 'msg: equality> =
     struct
         val Key: WidgetKey
         val Attributes: AttributesBundle
 
+        new(key: WidgetKey) =
+            { Key = key
+              Attributes = AttributesBundle(StackList.empty(), ValueNone, ValueNone, ValueNone) }
+
         new(key: WidgetKey, attributes: AttributesBundle) = { Key = key; Attributes = attributes }
 
         new(key: WidgetKey, scalar: ScalarAttribute) =
             { Key = key
-              Attributes = AttributesBundle(StackList.one scalar, ValueNone, ValueNone) }
+              Attributes = AttributesBundle(StackList.one scalar, ValueNone, ValueNone, ValueNone) }
 
         new(key: WidgetKey, scalarA: ScalarAttribute, scalarB: ScalarAttribute) =
             { Key = key
-              Attributes = AttributesBundle(StackList.two(scalarA, scalarB), ValueNone, ValueNone) }
+              Attributes = AttributesBundle(StackList.two(scalarA, scalarB), ValueNone, ValueNone, ValueNone) }
 
         new(key: WidgetKey, scalar1: ScalarAttribute, scalar2: ScalarAttribute, scalar3: ScalarAttribute) =
             { Key = key
-              Attributes = AttributesBundle(StackList.three(scalar1, scalar2, scalar3), ValueNone, ValueNone) }
+              Attributes = AttributesBundle(StackList.three(scalar1, scalar2, scalar3), ValueNone, ValueNone, ValueNone) }
+
+        new(key: WidgetKey, widget: WidgetAttribute) =
+            { Key = key
+              Attributes = AttributesBundle(StackList.empty(), ValueSome [| widget |], ValueNone, ValueNone) }
 
         [<EditorBrowsable(EditorBrowsableState.Never)>]
         member x.Compile() : Widget =
-            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes) =
+            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes, environmentAttributes) =
                 x.Attributes
 
             { Key = x.Key
@@ -41,19 +49,23 @@ type WidgetBuilder<'msg, 'marker when 'msg: equality> =
               ScalarAttributes =
                 match StackList.length &scalarAttributes with
                 | 0us -> ValueNone
-                | _ -> ValueSome(Array.sortInPlace (fun a -> a.Key) (StackList.toArray &scalarAttributes))
+                | _ -> ValueSome(Array.sortInPlace _.Key (StackList.toArray &scalarAttributes))
 
-              WidgetAttributes = ValueOption.map (Array.sortInPlace(fun a -> a.Key)) widgetAttributes
+              WidgetAttributes = ValueOption.map (Array.sortInPlace(_.Key)) widgetAttributes
 
+              WidgetCollectionAttributes = widgetCollectionAttributes |> ValueOption.map(Array.sortInPlace(_.Key))
 
-              WidgetCollectionAttributes = widgetCollectionAttributes |> ValueOption.map(Array.sortInPlace(fun a -> a.Key)) }
+              EnvironmentAttributes = environmentAttributes |> ValueOption.map(Array.sortInPlace(_.Key)) }
 
         [<EditorBrowsable(EditorBrowsableState.Never)>]
         member inline x.AddScalar(attr: ScalarAttribute) =
-            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes) =
+            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes, environmentAttributes) =
                 x.Attributes
 
-            WidgetBuilder<'msg, 'marker>(x.Key, struct (StackList.add(&scalarAttributes, attr), widgetAttributes, widgetCollectionAttributes))
+            WidgetBuilder<'msg, 'marker>(
+                x.Key,
+                struct (StackList.add(&scalarAttributes, attr), widgetAttributes, widgetCollectionAttributes, environmentAttributes)
+            )
 
         [<EditorBrowsable(EditorBrowsableState.Never)>]
         member inline x.AddOrReplaceScalar
@@ -62,26 +74,29 @@ type WidgetBuilder<'msg, 'marker when 'msg: equality> =
                 [<InlineIfLambda>] replaceWith: ScalarAttribute -> ScalarAttribute,
                 [<InlineIfLambda>] defaultWith: unit -> ScalarAttribute
             ) =
-            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes) =
+            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes, environmentAttributes) =
                 x.Attributes
 
             match StackList.tryFind(&scalarAttributes, (fun attr -> attr.Key = attrKey)) with
             | ValueNone ->
                 let attr = defaultWith()
 
-                WidgetBuilder<'msg, 'marker>(x.Key, struct (StackList.add(&scalarAttributes, attr), widgetAttributes, widgetCollectionAttributes))
+                WidgetBuilder<'msg, 'marker>(
+                    x.Key,
+                    struct (StackList.add(&scalarAttributes, attr), widgetAttributes, widgetCollectionAttributes, environmentAttributes)
+                )
 
             | ValueSome attr ->
                 let newAttr = replaceWith attr
 
                 let newAttrs =
                     StackList.replace(&scalarAttributes, (fun attr -> attr.Key = attrKey), newAttr)
 
-                WidgetBuilder<'msg, 'marker>(x.Key, struct (newAttrs, widgetAttributes, widgetCollectionAttributes))
+                WidgetBuilder<'msg, 'marker>(x.Key, struct (newAttrs, widgetAttributes, widgetCollectionAttributes, environmentAttributes))
 
         [<EditorBrowsable(EditorBrowsableState.Never)>]
         member x.AddWidget(attr: WidgetAttribute) =
-            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes) =
+            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes, environmentAttributes) =
                 x.Attributes
 
             let attribs = widgetAttributes
@@ -95,11 +110,11 @@ type WidgetBuilder<'msg, 'marker when 'msg: equality> =
                     attribs2[attribs.Length] <- attr
                     attribs2
 
-            WidgetBuilder<'msg, 'marker>(x.Key, struct (scalarAttributes, ValueSome res, widgetCollectionAttributes))
+            WidgetBuilder<'msg, 'marker>(x.Key, struct (scalarAttributes, ValueSome res, widgetCollectionAttributes, environmentAttributes))
 
         [<EditorBrowsable(EditorBrowsableState.Never)>]
         member x.AddWidgetCollection(attr: WidgetCollectionAttribute) =
-            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes) =
+            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes, environmentAttributes) =
                 x.Attributes
 
             let attribs = widgetCollectionAttributes
@@ -113,7 +128,32 @@ type WidgetBuilder<'msg, 'marker when 'msg: equality> =
                     attribs2[attribs.Length] <- attr
                     attribs2
 
-            WidgetBuilder<'msg, 'marker>(x.Key, struct (scalarAttributes, widgetAttributes, ValueSome res))
+            WidgetBuilder<'msg, 'marker>(x.Key, struct (scalarAttributes, widgetAttributes, ValueSome res, environmentAttributes))
+
+        [<EditorBrowsable(EditorBrowsableState.Never)>]
+        member inline x.AddEnvironment(key: EnvironmentAttributeKey, value: obj) =
+            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes, environmentAttributes) =
+                x.Attributes
+
+            let attr =
+                { Key = key
+#if DEBUG
+                  DebugName = $"Environment.{key}"
+#endif
+                  Value = value }
+
+            let attribs = environmentAttributes
+
+            let res =
+                match attribs with
+                | ValueNone -> [| attr |]
+                | ValueSome attribs ->
+                    let attribs2 = Array.zeroCreate(attribs.Length + 1)
+                    Array.blit attribs 0 attribs2 0 attribs.Length
+                    attribs2[attribs.Length] <- attr
+                    attribs2
+
+            WidgetBuilder<'msg, 'marker>(x.Key, struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes, ValueSome res))
     end
 
 
@@ -130,12 +170,12 @@ type CollectionBuilder<'msg, 'marker, 'itemMarker when 'msg: equality> =
 
         new(widgetKey: WidgetKey, scalars: StackList<ScalarAttribute>, attr: WidgetCollectionAttributeDefinition) =
             { WidgetKey = widgetKey
-              Attributes = AttributesBundle(scalars, ValueNone, ValueNone)
+              Attributes = AttributesBundle(scalars, ValueNone, ValueNone, ValueNone)
               Attr = attr }
 
         new(widgetKey: WidgetKey, attr: WidgetCollectionAttributeDefinition) =
             { WidgetKey = widgetKey
-              Attributes = AttributesBundle(StackList.empty(), ValueNone, ValueNone)
+              Attributes = AttributesBundle(StackList.empty(), ValueNone, ValueNone, ValueNone)
               Attr = attr }
 
         new(widgetKey: WidgetKey, attr: WidgetCollectionAttributeDefinition, attributes: AttributesBundle) =
@@ -145,16 +185,16 @@ type CollectionBuilder<'msg, 'marker, 'itemMarker when 'msg: equality> =
 
         new(widgetKey: WidgetKey, attr: WidgetCollectionAttributeDefinition, scalar: ScalarAttribute) =
             { WidgetKey = widgetKey
-              Attributes = AttributesBundle(StackList.one scalar, ValueNone, ValueNone)
+              Attributes = AttributesBundle(StackList.one scalar, ValueNone, ValueNone, ValueNone)
               Attr = attr }
 
         new(widgetKey: WidgetKey, attr: WidgetCollectionAttributeDefinition, scalarA: ScalarAttribute, scalarB: ScalarAttribute) =
             { WidgetKey = widgetKey
-              Attributes = AttributesBundle(StackList.two(scalarA, scalarB), ValueNone, ValueNone)
+              Attributes = AttributesBundle(StackList.two(scalarA, scalarB), ValueNone, ValueNone, ValueNone)
               Attr = attr }
 
         member inline x.Run(c: Content<'msg>) =
-            let struct (scalars, widgets, widgetCollections) = x.Attributes
+            let struct (scalars, widgets, widgetCollections, environments) = x.Attributes
 
             let attrValue =
                 match MutStackArray1.toArraySlice &c.Widgets with
@@ -168,7 +208,7 @@ type CollectionBuilder<'msg, 'marker, 'itemMarker when 'msg: equality> =
                 | ValueNone -> ValueSome([| widgetCollAttr |])
                 | ValueSome widgetCollectionAttributes -> ValueSome(Array.appendOne widgetCollAttr widgetCollectionAttributes)
 
-            WidgetBuilder<'msg, 'marker>(x.WidgetKey, AttributesBundle(scalars, widgets, widgetCollections))
+            WidgetBuilder<'msg, 'marker>(x.WidgetKey, AttributesBundle(scalars, widgets, widgetCollections, environments))
 
         member inline _.Combine(a: Content<'msg>, b: Content<'msg>) : Content<'msg> =
             let res = MutStackArray1.combineMut(&a.Widgets, b.Widgets)
@@ -191,13 +231,13 @@ type CollectionBuilder<'msg, 'marker, 'itemMarker when 'msg: equality> =
 
         [<EditorBrowsable(EditorBrowsableState.Never)>]
         member inline x.AddScalar(attr: ScalarAttribute) =
-            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes) =
+            let struct (scalarAttributes, widgetAttributes, widgetCollectionAttributes, environmentAttributes) =
                 x.Attributes
 
             CollectionBuilder<'msg, 'marker, 'itemMarker>(
                 x.WidgetKey,
                 x.Attr,
-                struct (StackList.add(&scalarAttributes, attr), widgetAttributes, widgetCollectionAttributes)
+                struct (StackList.add(&scalarAttributes, attr), widgetAttributes, widgetCollectionAttributes, environmentAttributes)
             )
 
     end
@@ -251,7 +291,7 @@ type SingleChildBuilder<'msg, 'marker, 'childMarker when 'msg: equality> =
     new(widgetKey: WidgetKey, attr: WidgetAttributeDefinition) =
         { WidgetKey = widgetKey
           Attr = attr
-          AttributesBundle = AttributesBundle(StackList.empty(), ValueNone, ValueNone) }
+          AttributesBundle = AttributesBundle(StackList.empty(), ValueNone, ValueNone, ValueNone) }
 
     new(widgetKey: WidgetKey, attr: WidgetAttributeDefinition, attributesBundle: AttributesBundle) =
         { WidgetKey = widgetKey
@@ -273,7 +313,9 @@ type SingleChildBuilder<'msg, 'marker, 'childMarker when 'msg: equality> =
 
     member inline this.Run([<InlineIfLambda>] result: SingleChildBuilderStep<'msg, 'childMarker>) =
         let childAttr = this.Attr.WithValue(result.Invoke().Compile())
-        let struct (scalars, widgets, widgetCollections) = this.AttributesBundle
+
+        let struct (scalars, widgets, widgetCollections, environments) =
+            this.AttributesBundle
 
         WidgetBuilder<'msg, 'marker>(
             this.WidgetKey,
@@ -282,6 +324,7 @@ type SingleChildBuilder<'msg, 'marker, 'childMarker when 'msg: equality> =
                 (match widgets with
                  | ValueNone -> ValueSome [| childAttr |]
                  | ValueSome widgets -> ValueSome(Array.appendOne childAttr widgets)),
-                widgetCollections
+                widgetCollections,
+                environments
             )
         )

src/Fabulous/Components/Component.fs

@@ -27,7 +27,8 @@ type Component
 
     member private this.MergeAttributes(rootWidget: Widget, componentWidgetOpt: Widget voption) =
         match componentWidgetOpt with
-        | ValueNone -> struct (rootWidget.ScalarAttributes, rootWidget.WidgetAttributes, rootWidget.WidgetCollectionAttributes)
+        | ValueNone ->
+            struct (rootWidget.ScalarAttributes, rootWidget.WidgetAttributes, rootWidget.WidgetCollectionAttributes, rootWidget.EnvironmentAttributes)
 
         | ValueSome componentWidget ->
             let componentScalars =
@@ -60,7 +61,14 @@ type Component
                 | ValueNone, ValueSome attrs -> ValueSome attrs
                 | ValueSome widgetAttrs, ValueSome componentAttrs -> ValueSome(Array.append componentAttrs widgetAttrs)
 
-            struct (scalars, widgets, widgetColls)
+            let environments =
+                match struct (rootWidget.EnvironmentAttributes, componentWidget.EnvironmentAttributes) with
+                | ValueNone, ValueNone -> ValueNone
+                | ValueSome attrs, ValueNone
+                | ValueNone, ValueSome attrs -> ValueSome attrs
+                | ValueSome widgetAttrs, ValueSome componentAttrs -> ValueSome(Array.append componentAttrs widgetAttrs)
+
+            struct (scalars, widgets, widgetColls, environments)
 
     member this.CreateView(componentWidget: Widget voption) =
         _isReadyForRenderRequest <- false
@@ -74,7 +82,7 @@ type Component
         _treeContext <- treeContext
         _context <- context
 
-        let struct (scalars, widgets, widgetColls) =
+        let struct (scalars, widgets, widgetColls, environments) =
             this.MergeAttributes(rootWidget, componentWidget)
 
         let rootWidget: Widget =
@@ -84,7 +92,8 @@ type Component
 #endif
               ScalarAttributes = scalars
               WidgetAttributes = widgets
-              WidgetCollectionAttributes = widgetColls }
+              WidgetCollectionAttributes = widgetColls
+              EnvironmentAttributes = environments }
 
         // Create the actual view
         let widgetDef = WidgetDefinitionStore.get rootWidget.Key
@@ -115,7 +124,7 @@ type Component
         _treeContext <- treeContext
         _context <- context
 
-        let struct (scalars, widgets, widgetColls) =
+        let struct (scalars, widgets, widgetColls, environments) =
             this.MergeAttributes(rootWidget, ValueSome componentWidget)
 
         let rootWidget: Widget =
@@ -125,7 +134,8 @@ type Component
 #endif
               ScalarAttributes = scalars
               WidgetAttributes = widgets
-              WidgetCollectionAttributes = widgetColls }
+              WidgetCollectionAttributes = widgetColls
+              EnvironmentAttributes = environments }
 
         // Attach the widget to the existing view
         let widgetDef = WidgetDefinitionStore.get rootWidget.Key