Add new Bdnd project (#13931)

.github/agents/test-platform.md

@@ -369,7 +369,7 @@ does not serve silently gets the newest one it does.
    `feat(release): v-X.Y.Z` commit on `develop` has its tag: an untagged release is answered by the previous one,
    without a word.
 2. **What it does serve.** `mcp -McpVersion X.Y.Z` for each. The library tools (`Search*`, `Get*` and `Inspect*` of BlazorUI,
-   Brouter, Butil, Bswup, Bmotion and - from the first release that ships them - Bink, Balette, BbScanner, BlazeDb, Blow, Bonboarding, Bortable, Blex, Bmage and Bsqlite) and the source tools (`FindBitPlatformSymbols`, `GetBitPlatformSymbolSource`,
+   Brouter, Butil, Bswup, Bmotion and - from the first release that ships them - Bink, Balette, BbScanner, Bdnd, BlazeDb, Blow, Bonboarding, Bortable, Blex, Bmage and Bsqlite) and the source tools (`FindBitPlatformSymbols`, `GetBitPlatformSymbolSource`,
    `SearchBitPlatformCode`) must all be there. Only the five shared ones (`AskGitHubRepository`,
    `SendBitPlatformFeedback`, `microsoft_docs_*`) means no release is served at all, and the README's
    *PlatformWebsite's MCP* section says why that happens. The server version it reports is the website's own build,
@@ -388,7 +388,7 @@ does not serve silently gets the newest one it does.
 4. **The answers are good.** Put one real task to each library's `Search` tool, worded the way a developer would
    describe it - BlazorUI "a dropdown the user can also type into", Butil "copy text to the clipboard", Bmotion "fade
    a list item in", Brouter "a route parameter that must be a number", Bswup "show the download progress of the app's
-   update", Bink "a signature pad that exports a PNG", Balette "a command that asks for a name before it runs", BbScanner "scan a QR code from an uploaded photo", BlazeDb "a todo list that survives a page reload", Blow "a flow chart that lays itself out left to right", Bonboarding "a step that waits for a panel that loads later", Bortable "a kanban board whose cards move between columns", Blex "a counter whose value survives a page reload", Bmage "shrink an uploaded photo under 200 KB without its location", Bsqlite "keep the database when OPFS is not available" - follow up with the `Get` tool it points to, and ask `SearchBitPlatformCode` about the Boilerplate. An
+   update", Bink "a signature pad that exports a PNG", Balette "a command that asks for a name before it runs", BbScanner "scan a QR code from an uploaded photo", Bdnd "reorder a list by dragging its items", BlazeDb "a todo list that survives a page reload", Blow "a flow chart that lays itself out left to right", Bonboarding "a step that waits for a panel that loads later", Bortable "a kanban board whose cards move between columns", Blex "a counter whose value survives a page reload", Bmage "shrink an uploaded photo under 200 KB without its location", Bsqlite "keep the database when OPFS is not available" - follow up with the `Get` tool it points to, and ask `SearchBitPlatformCode` about the Boilerplate. An
    answer must be on topic, specific and true to the version asked for; one that answers wrongly is a failure too.
 
 Like an E2E failure, an MCP problem is fixed in `src/Websites/Platform` or in the library's own MCP server, and goes

.github/copilot-instructions.md

@@ -46,8 +46,8 @@
 ## Rules
 
 **RULE 1:** If a task (question, code modification or review) involves the use of bit BlazorUI components (e.g., `BitButton`, `BitTooltip`, `BitTextField`),
-or refers to `bitplatform`, `bit Bswup`, `bit Butil`, `bit Bmotion`, `bit Bink`, `bit Balette`, `bit BbScanner`, `bit BlazeDb`, `bit Blow`, `bit Bonboarding`, `bit Bortable`, `bit Blex`, `bit Bmage`, `bit Bsqlite`, `bit Brouter`, or `bit Boilerplate`, or involves UI components without explicitly specifying their UI toolkit,
-you **MUST** use the `bitplatform` MCP server's tools - start with the matching `Search<Library>` tool (e.g. `SearchBitBlazorUI`, `SearchBswup`, `SearchButil`, `SearchBmotion`, `SearchBink`, `SearchBalette`, `SearchBbScanner`, `SearchBlazeDb`, `SearchBlow`, `SearchBonboarding`, `SearchBortable`, `SearchBlex`, `SearchBmage`, `SearchBsqlite`, `SearchBrouter`) and follow the calls it names - to find the correct implementation and usage patterns before writing or changing any code.
+or refers to `bitplatform`, `bit Bswup`, `bit Butil`, `bit Bmotion`, `bit Bink`, `bit Balette`, `bit BbScanner`, `bit Bdnd`, `bit BlazeDb`, `bit Blow`, `bit Bonboarding`, `bit Bortable`, `bit Blex`, `bit Bmage`, `bit Bsqlite`, `bit Brouter`, or `bit Boilerplate`, or involves UI components without explicitly specifying their UI toolkit,
+you **MUST** use the `bitplatform` MCP server's tools - start with the matching `Search<Library>` tool (e.g. `SearchBitBlazorUI`, `SearchBswup`, `SearchButil`, `SearchBmotion`, `SearchBink`, `SearchBalette`, `SearchBbScanner`, `SearchBdnd`, `SearchBlazeDb`, `SearchBlow`, `SearchBonboarding`, `SearchBortable`, `SearchBlex`, `SearchBmage`, `SearchBsqlite`, `SearchBrouter`) and follow the calls it names - to find the correct implementation and usage patterns before writing or changing any code.
 
 **End of RULE 1**
 

.github/workflows/all.cd.yml

@@ -95,6 +95,12 @@ jobs:
     uses: ./.github/workflows/bbscanner.demo.cd.yml
     secrets: inherit
 
+  bdnd_demo:
+    name: bdnd demo
+    if: inputs.server
+    uses: ./.github/workflows/bdnd.demo.cd.yml
+    secrets: inherit
+
   blazedb_demo:
     name: blazedb demo
     if: inputs.server

.github/workflows/bdnd.demo.cd.yml

@@ -0,0 +1,75 @@
+name: Bdnd Demo CD
+
+on:
+  workflow_dispatch:
+  workflow_call:
+
+permissions:
+  contents: read
+
+jobs:
+
+  build_blazor_wasm:
+    name: build blazor wasm
+    runs-on: ubuntu-24.04
+
+    steps:
+
+    - name: Checkout source code
+      uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+      with:
+          persist-credentials: false
+
+    - name: Setup .NET
+      uses: actions/setup-dotnet@a98b56852c35b8e3190ac28c8c2271da59106c68 # v6.0.0
+      with:
+        global-json-file: src/global.json
+
+    - uses: actions/setup-node@949feb2413d6458794dcd2491c4babbbce0c15c1 # v7.1.0
+      with:
+        node-version: 24
+
+    - name: Install wasm
+      run:  cd src && dotnet workload install wasm-tools
+
+    - name: Publish
+      run: dotnet publish src/Bdnd/Demo/Server/Bit.Bdnd.Demo.Server.csproj -c Release -o server -p:Version="${{ vars.APP_VERSION}}" -p:InvariantGlobalization=true
+
+    # Server-owned; C:\inetpub keeps its own copies.
+    - name: Strip server-owned files from bundle
+      run: rm -fv server/appsettings*.json server/AppCertificate.* server/AppleAuthKey.p8 server/*.pfx
+
+    - name: Upload artifact
+      uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
+      with:
+        name: BdndDemo
+        path: server
+        include-hidden-files: true
+
+  deploy_server:
+    name: deploy
+    needs: build_blazor_wasm
+    runs-on: [self-hosted, Windows, X64, bitplatform-iis]
+    environment:
+      name: production
+      url: 'https://bdnd.bitplatform.dev'
+
+    steps:
+
+    - name: Checkout deploy action
+      uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+      with:
+          persist-credentials: false
+          fetch-depth: 1
+          sparse-checkout: .github/actions
+
+    - name: Deploy
+      uses: ./.github/actions/deploy-to-server
+      with:
+        artifact-name: BdndDemo
+        app-pool: Bdnd
+        site-path: C:\inetpub\BdndDemo
+        sentinel-file: Bit.Bdnd.Demo.Server.dll
+        health-check-url: 'https://bdnd.bitplatform.dev/'
+        cloudflare-zone-id: ${{ secrets.CLOUDFLARE_ZONE_ID }}
+        cloudflare-token: ${{ secrets.CLOUDFLARE_TOKEN }}

.github/workflows/bit.ci.Bdnd.e2e.yml

@@ -0,0 +1,63 @@
+name: bit platform CI - Bdnd E2E
+
+# The browser suite: the demo (prerendered, then running on WebAssembly) driven in Chromium with Playwright. It
+# takes far longer than the build-and-unit pipeline (bit.ci.Bdnd.yml), so it runs only when started by hand. See
+# src/Bdnd/Tests/Bit.Bdnd.Tests.E2E/README.md for what it proves and how to run it locally.
+
+on:
+  workflow_dispatch:
+
+env:
+  DOTNET_SYSTEM_CONSOLE_ALLOW_ANSI_COLOR_REDIRECTION: true
+
+permissions:
+  contents: read
+
+jobs:
+
+  e2e:
+    name: Bdnd E2E (Chromium)
+    runs-on: ubuntu-24.04
+    timeout-minutes: 60
+
+    steps:
+
+    - name: Checkout source code
+      uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+      with:
+          persist-credentials: false
+
+    - name: Setup .NET 10.0
+      uses: actions/setup-dotnet@a98b56852c35b8e3190ac28c8c2271da59106c68 # v6.0.0
+      with:
+        global-json-file: src/global.json
+
+    - uses: actions/setup-node@949feb2413d6458794dcd2491c4babbbce0c15c1 # v7.1.0
+      with:
+        node-version: 24
+
+    - name: dotnet workload restore
+      run: cd src/Bdnd && dotnet workload restore
+
+    - name: Build the demo and the E2E suite
+      run: |
+        dotnet build src/Bdnd/Demo/Server/Bit.Bdnd.Demo.Server.csproj -c Release
+        dotnet build src/Bdnd/Tests/Bit.Bdnd.Tests.E2E/Bit.Bdnd.Tests.E2E.csproj -c Release
+
+    - name: Install Playwright Chromium
+      run: pwsh src/Bdnd/Tests/Bit.Bdnd.Tests.E2E/bin/Release/net10.0/playwright.ps1 install --with-deps chromium
+
+    - name: Run E2E tests
+      # Run from inside src so src/global.json's Microsoft.Testing.Platform runner setting applies.
+      run: >
+        cd src/Bdnd/Tests/Bit.Bdnd.Tests.E2E &&
+        dotnet test -c Release --no-build
+        --report-trx --report-trx-filename bdnd-e2e.trx
+
+    - name: Upload test results
+      if: always()
+      uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
+      with:
+        name: bdnd-e2e
+        path: '**/bdnd-e2e.trx'
+        if-no-files-found: ignore

.github/workflows/bit.ci.Bdnd.yml

@@ -0,0 +1,62 @@
+name: bit platform CI - Bdnd
+
+# Build, unit tests and MCP server tests. The browser suite lives in bit.ci.Bdnd.e2e.yml and runs on demand only.
+
+on:
+  workflow_dispatch:
+  workflow_call:
+  pull_request:
+    paths:
+    - 'src/Bdnd/**'
+
+env:
+  DOTNET_SYSTEM_CONSOLE_ALLOW_ANSI_COLOR_REDIRECTION: true
+
+permissions:
+  contents: read
+
+jobs:
+  build-Bdnd:
+    if: startsWith(github.event.pull_request.title, 'Prerelease') != true && startsWith(github.event.pull_request.title, 'Release') != true && startsWith(github.event.pull_request.title, 'Version') != true
+    name: build Bit.Bdnd
+    runs-on: ubuntu-24.04
+
+    steps:
+
+    - name: Checkout source code
+      uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+      with:
+          persist-credentials: false
+
+    - name: Setup .NET 10.0
+      uses: actions/setup-dotnet@a98b56852c35b8e3190ac28c8c2271da59106c68 # v6.0.0
+      with:
+        global-json-file: src/global.json
+
+    - name: Setup .NET 9.0
+      uses: actions/setup-dotnet@a98b56852c35b8e3190ac28c8c2271da59106c68 # v6.0.0
+      with:
+        dotnet-version: 9.0.x
+
+    - name: Setup .NET 8.0
+      uses: actions/setup-dotnet@a98b56852c35b8e3190ac28c8c2271da59106c68 # v6.0.0
+      with:
+        dotnet-version: 8.0.x
+
+    - uses: actions/setup-node@949feb2413d6458794dcd2491c4babbbce0c15c1 # v7.1.0
+      with:
+        node-version: 24
+
+    - name: dotnet workload restore
+      run:  cd src/Bdnd && dotnet workload restore
+
+    - name: dotnet build
+      run: dotnet build src/Bdnd/Bit.Bdnd.slnx
+
+    - name: dotnet test
+      # Run from inside src so src/global.json's "test" runner setting applies
+      # (from the repo root the SDK falls back to the unsupported VSTest path).
+      run: cd src/Bdnd/Tests/Bit.Bdnd.Tests && dotnet test --no-build
+
+    - name: dotnet test (MCP server)
+      run: cd src/Bdnd/Tests/Bit.Bdnd.Tests.Mcp && dotnet test --no-build

.github/workflows/nuget.org.yml

@@ -8,6 +8,7 @@ on:
     paths:
       - 'src/Balette/**'
       - 'src/BbScanner/**'
+      - 'src/Bdnd/**'
       - 'src/BlazorUI/**'
       - 'src/Bink/**'
       - 'src/BlazeDb/**'
@@ -216,6 +217,11 @@ jobs:
     - name: dotnet pack BbScanner
       run: dotnet pack src/BbScanner/Bit.BbScanner/Bit.BbScanner.csproj --output . --configuration Release
 
+    - name: dotnet build Bdnd
+      run: dotnet build src/Bdnd/Bit.Bdnd/Bit.Bdnd.csproj -c Release -p:GeneratePackageOnBuild=false -p:WarningLevel=0 -p:RunCodeAnalysis=false
+    - name: dotnet pack Bdnd
+      run: dotnet pack src/Bdnd/Bit.Bdnd/Bit.Bdnd.csproj --output . --configuration Release
+
     - name: dotnet build BlazeDb
       run: dotnet build src/BlazeDb/Bit.BlazeDb/Bit.BlazeDb.csproj -c Release -p:GeneratePackageOnBuild=false -p:WarningLevel=0 -p:RunCodeAnalysis=false
     - name: dotnet pack BlazeDb

.github/workflows/prerelease.nuget.org.yml

@@ -193,6 +193,11 @@ jobs:
     - name: dotnet pack BbScanner
       run: dotnet pack src/BbScanner/Bit.BbScanner/Bit.BbScanner.csproj --output . --configuration Release
 
+    - name: dotnet build Bdnd
+      run: dotnet build src/Bdnd/Bit.Bdnd/Bit.Bdnd.csproj -c Release -p:GeneratePackageOnBuild=false -p:WarningLevel=0 -p:RunCodeAnalysis=false
+    - name: dotnet pack Bdnd
+      run: dotnet pack src/Bdnd/Bit.Bdnd/Bit.Bdnd.csproj --output . --configuration Release
+
     - name: dotnet build BlazeDb
       run: dotnet build src/BlazeDb/Bit.BlazeDb/Bit.BlazeDb.csproj -c Release -p:GeneratePackageOnBuild=false -p:WarningLevel=0 -p:RunCodeAnalysis=false
     - name: dotnet pack BlazeDb

.gitignore

@@ -297,6 +297,9 @@ _book
 /src/BlazeDb/Bit.BlazeDb.Browser/Scripts/**/*.js
 /src/BlazeDb/Bit.BlazeDb.Browser/wwwroot/**/*.js
 
+/src/Bdnd/Bit.Bdnd/Scripts/**/*.js
+/src/Bdnd/Bit.Bdnd/wwwroot/**/*.js
+
 /src/Blow/Bit.Blow/Scripts/**/*.js
 /src/Blow/Bit.Blow/wwwroot/**/*.js
 /src/Blow/Bit.Blow/wwwroot/**/*.css

README.md

@@ -39,6 +39,7 @@ bit new MyApp
 
 - [***bit BlazorUI***](https://blazorui.bitplatform.dev) (`Bit.BlazorUI`): 90+ high-performance, accessible components with Dark and Light themes and RTL support, split across `Bit.BlazorUI`, `Bit.BlazorUI.Extras` (DataGrid, Chart, PdfViewer, RichTextEditor, Map, FullCalendar, CountryPicker, TimeZonePicker, and more), `Bit.BlazorUI.Icons` and `Bit.BlazorUI.Assets`.
 - [***BbScanner***](src/BbScanner/README.md) (`Bit.BbScanner`): A dependency-free barcode scanner for Blazor that reads QR Code, Data Matrix, Code 128, Code 39, EAN-13, EAN-8, UPC-A, UPC-E and ITF from the camera or from still images. The decoding is written from scratch in C#; the browser only opens the camera and copies pixels.
+- [***Bdnd***](src/Bdnd/README.md) (`Bit.Bdnd`): A declarative drag-and-drop library for Blazor inspired by React DnD, with typed items matched to drop targets by type, custom drag previews, drag handles, sortable lists, nested sources and targets, and native file, text and link drops. The drag state lives in C#; the browser only configures the native drag and tracks hover.
 - [***Bink***](src/Bink/README.md) (`Bit.Bink`): A Blazor-native drawing and ink library, with pressure- and tilt-aware strokes, brushes, erasers, shapes, annotations, selection, layers, undo/redo, real-time collaboration and SVG/PNG export. The document model and the drawing engine run in C#; the browser only captures input and paints.
 - [***Balette***](src/Balette/README.md) (`Bit.Balette`): A Blazor-native, keyboard-first command palette (`Ctrl+K` / `⌘K`), with fzf-style fuzzy search, nested pages, prefix modes, async sources, recents and frecency, global shortcuts and sequences, prompts, multi-select and full theming. Matching and ranking run in C#; the browser only opens the dialog and listens for keys.
 - [***Blow***](src/Blow/README.md) (`Bit.Blow`): A Blazor-native library for node-based UIs, editors, flow charts and diagrams - a Blazor counterpart to React Flow - with a pannable, zoomable canvas, draggable, resizable and connectable nodes, sub-flows, auto-layout, alignment guides, undo/redo, copy/paste and full keyboard accessibility. Interaction, layout and geometry run in C#; the browser only measures the DOM.

src/Balette/Demo/Server/Services/BaletteXmlDocs.cs

@@ -189,9 +189,10 @@ private static string Reference(XElement element)
         var arguments = target.IndexOf('(', StringComparison.Ordinal);
         if (arguments > 0) target = target[..arguments];
 
-        // Drop the arity marker of a generic type ("SomeGeneric`1").
-        var arity = target.IndexOf('`', StringComparison.Ordinal);
-        if (arity > 0) target = target[..arity];
+        // Drop the arity markers of generic types and methods ("SomeGeneric`1", "GetItem``1") wherever
+        // they sit: a member of a generic type has one in the middle of its cref, and cutting the text
+        // at the first one would drop the member and keep the namespace.
+        target = ArityRegex().Replace(target, string.Empty);
 
         var parts = target.Split('.');
 
@@ -209,4 +210,7 @@ private static string Reference(XElement element)
 
     [GeneratedRegex(@"[ \t]{2,}")]
     private static partial Regex RepeatedSpaceRegex();
+
+    [GeneratedRegex(@"`+\d+")]
+    private static partial Regex ArityRegex();
 }

src/BbScanner/Demo/Server/Services/BbScannerXmlDocs.cs

@@ -189,9 +189,10 @@ private static string Reference(XElement element)
         var arguments = target.IndexOf('(', StringComparison.Ordinal);
         if (arguments > 0) target = target[..arguments];
 
-        // Drop the arity marker of a generic type ("SomeGeneric`1").
-        var arity = target.IndexOf('`', StringComparison.Ordinal);
-        if (arity > 0) target = target[..arity];
+        // Drop the arity markers of generic types and methods ("SomeGeneric`1", "GetItem``1") wherever
+        // they sit: a member of a generic type has one in the middle of its cref, and cutting the text
+        // at the first one would drop the member and keep the namespace.
+        target = ArityRegex().Replace(target, string.Empty);
 
         var parts = target.Split('.');
 
@@ -209,4 +210,7 @@ private static string Reference(XElement element)
 
     [GeneratedRegex(@"[ \t]{2,}")]
     private static partial Regex RepeatedSpaceRegex();
+
+    [GeneratedRegex(@"`+\d+")]
+    private static partial Regex ArityRegex();
 }

src/Bdnd/Bit.Bdnd.slnx

@@ -0,0 +1,19 @@
+<Solution>
+    <Folder Name="/.Solution Items/">
+        <File Path="../../.gitignore" />
+        <File Path="../.editorconfig" />
+        <File Path="../Bit.Build.props" />
+        <File Path="../global.json" />
+        <File Path="README.md" />
+    </Folder>
+    <Folder Name="/Demo/">
+        <Project Path="Demo/Client/Bit.Bdnd.Demo.Client.csproj" />
+        <Project Path="Demo/Server/Bit.Bdnd.Demo.Server.csproj" />
+    </Folder>
+    <Folder Name="/Tests/">
+        <Project Path="Tests/Bit.Bdnd.Tests/Bit.Bdnd.Tests.csproj" />
+        <Project Path="Tests/Bit.Bdnd.Tests.Mcp/Bit.Bdnd.Tests.Mcp.csproj" />
+        <Project Path="Tests/Bit.Bdnd.Tests.E2E/Bit.Bdnd.Tests.E2E.csproj" />
+    </Folder>
+    <Project Path="Bit.Bdnd/Bit.Bdnd.csproj" />
+</Solution>