feat: cross-platform reactive extensions gap analysis — 40+ new operators

.gitattributes

@@ -6,4 +6,7 @@
 *.cs text
 
 # Declare files that will always have CRLF line endings on checkout.
-*.sln text eol=crlf
+*.sln text eol=crlf
+
+# GitHub Agentic Workflows lock files
+.github/workflows/*.lock.yml linguist-generated=true merge=ours

.github/workflows/api-sync-check.md

@@ -0,0 +1,121 @@
+---
+emoji: 🔄
+description: Weekly check to keep R3Ext APIs and features in sync with ReactiveUI and DynamicData. Identifies out-of-sync APIs and opens a pull request with the necessary updates.
+on:
+  schedule: weekly on Monday
+  skip-if-match: 'is:pr is:open label:api-sync in:title "[api-sync]"'
+permissions:
+  contents: read
+  issues: read
+  pull-requests: read
+tools:
+  github:
+    mode: gh-proxy
+    toolsets: [default]
+network:
+  allowed: [dotnet]
+safe-outputs:
+  create-pull-request:
+    title-prefix: "[api-sync] "
+    labels: [api-sync, automation]
+    draft: true
+    reviewers: [copilot]
+    allowed-files:
+      - "R3Ext/**/*.cs"
+      - "R3.DynamicData/**/*.cs"
+      - "R3Ext.Bindings.SourceGenerator/**/*.cs"
+      - "R3Ext.Bindings.MauiTargets/**/*.cs"
+      - "docs/**/*.md"
+      - "README.md"
+---
+
+# API Sync Check — ReactiveUI & DynamicData
+
+## Goal
+
+Keep R3Ext aligned with the latest ReactiveUI and DynamicData APIs and features. Each week:
+
+1. Inspect recent commits and releases in both upstream repos.
+2. Compare against the current R3Ext implementation.
+3. If gaps exist, produce a pull request with the necessary source updates.
+4. If everything is already in sync, call `noop`.
+
+## Context
+
+- **R3Ext repo (this repo)** — a reactive MVVM + dynamic-data library built on R3.
+  - `R3Ext/` — ReactiveUI-compatible APIs: commands, interactions, bindings, MVVM helpers.
+  - `R3.DynamicData/` — DynamicData port: observable caches, lists, operators, change sets.
+- **ReactiveUI upstream**: `https://github.com/reactiveui/reactiveui`
+- **DynamicData upstream**: `https://github.com/reactivemarbles/DynamicData`
+
+## Steps
+
+### 1 — Gather upstream changes
+
+Use `gh` to inspect each upstream repository.
+
+For **ReactiveUI** (`reactiveui/reactiveui`):
+- Fetch commits from the last 7 days on the default branch.
+- Fetch the latest release tag and release notes.
+- List recently modified public C# files to spot new or changed public APIs (classes, interfaces, public methods/properties).
+
+For **DynamicData** (`reactivemarbles/DynamicData`):
+- Fetch commits from the last 7 days on the default branch.
+- Fetch the latest release tag and release notes.
+- List recently modified public C# files to spot new or changed public APIs.
+
+### 2 — Inspect the current R3Ext implementation
+
+Read relevant files in this repo to understand the current state:
+- `R3Ext/Commands/` — RxCommand implementations.
+- `R3Ext/Interactions/` — RxInteraction implementations.
+- `R3Ext/Bindings/` — binding helpers and source-generator hooks.
+- `R3Ext/Extensions/` — observable extension methods.
+- `R3.DynamicData/` — DynamicData port.
+
+### 3 — Identify gaps
+
+Compare the upstream public API surface against what R3Ext implements:
+
+- **Missing APIs**: public types or members in the upstream that have no R3Ext equivalent.
+- **Signature drift**: existing R3Ext methods whose signatures no longer match the upstream (parameter types, return types, overloads).
+- **New features**: functionality added upstream (new operators, new command overloads, new change-set types) not yet present in R3Ext.
+- **Removed/deprecated upstream APIs**: flag any that should also be deprecated in R3Ext.
+
+Ignore internal, private, or test-only members. Ignore platform-specific code that does not apply to R3Ext's .NET / MAUI targets.
+
+### 4 — Apply updates
+
+For each identified gap:
+- Add or update the corresponding C# source file(s) to bring R3Ext in line with the upstream API.
+- Follow the existing code style: XML doc comments for public members, no reflection, AOT-safe patterns.
+- Prefer additive changes (new overloads, new types) over breaking changes. If a breaking change is required, mark it with `// TODO: breaking change — <reason>` and note it in the PR body.
+- Do not modify test files or benchmark files.
+
+### 5 — Produce output
+
+**If updates were made**: create a pull request using the `create-pull-request` safe output.
+
+The PR body must include:
+
+```
+## Summary
+
+Brief description of what changed and why.
+
+## ReactiveUI changes
+- List specific upstream commits or release notes that motivated each change.
+
+## DynamicData changes
+- List specific upstream commits or release notes that motivated each change.
+
+## Breaking changes (if any)
+- Describe any breaking changes or API removals.
+```
+
+**If nothing is out of sync**: call `noop` with a short message such as "R3Ext APIs are already in sync with ReactiveUI and DynamicData — no changes needed."
+
+## Safe Outputs
+
+- Use `create-pull-request` to open a draft PR when source changes are produced.
+- Use `noop` when R3Ext is already in sync and no code changes are needed.

.github/workflows/ci-cd.yml

@@ -58,64 +58,45 @@ jobs:
 
             - name: Restore dependencies (libraries and tests only)
               run: |
-                  # Avoid restoring the MAUI SampleApp on Linux runners (iOS/macCatalyst workloads not available)
-                  dotnet restore R3Ext/R3Ext.csproj
-                  dotnet restore R3Ext.Bindings.SourceGenerator/R3Ext.Bindings.SourceGenerator.csproj
-                  dotnet restore R3Ext.Bindings.MauiTargets/R3Ext.Bindings.MauiTargets.csproj
-                  dotnet restore R3.DynamicData/R3.DynamicData.csproj
+                  # Auto-discover packable library projects; excludes tests, samples, and benchmarks
+                  # (those set <IsPackable>false</IsPackable> or omit the property on executable/test targets).
+                  # New shippable libraries are picked up automatically once they set <IsPackable>true</IsPackable>.
+                  PACKABLE=$(find . -name "*.csproj" -not -path "*/obj/*" | xargs grep -l '<IsPackable>true</IsPackable>' | sort)
+                  for proj in $PACKABLE; do
+                      dotnet restore "$proj"
+                  done
+                  # Test projects are not packable but must be restored to run tests
                   dotnet restore R3Ext.Tests/R3Ext.Tests.csproj
-                  dotnet restore R3.DynamicData.Tests/R3.DynamicData.Tests.csproj
+                  dotnet restore R3Ext.DynamicData.Tests/R3Ext.DynamicData.Tests.csproj
 
             - name: Build Libraries (exclude samples)
               run: |
                   export DOTNET_USE_SHARED_COMPILATION=false
-                  # Build source generator first (dependency for main library)
-                  dotnet build R3Ext.Bindings.SourceGenerator/R3Ext.Bindings.SourceGenerator.csproj --configuration Release --no-restore \
-                    /p:Version=${{ steps.gitversion.outputs.nuGetVersionV2 }} \
-                    /p:AssemblyVersion=${{ steps.gitversion.outputs.assemblySemVer }} \
-                    /p:FileVersion=${{ steps.gitversion.outputs.assemblySemFileVer }} \
-                    /p:InformationalVersion=${{ steps.gitversion.outputs.informationalVersion }}
-
-                  # Build main library (uses source generator)
-                  dotnet build R3Ext/R3Ext.csproj --configuration Release --no-restore \
-                    /p:Version=${{ steps.gitversion.outputs.nuGetVersionV2 }} \
-                    /p:AssemblyVersion=${{ steps.gitversion.outputs.assemblySemVer }} \
-                    /p:FileVersion=${{ steps.gitversion.outputs.assemblySemFileVer }} \
-                    /p:InformationalVersion=${{ steps.gitversion.outputs.informationalVersion }}
-
-                  # Build MAUI targets
-                  dotnet build R3Ext.Bindings.MauiTargets/R3Ext.Bindings.MauiTargets.csproj --configuration Release --no-restore \
-                    /p:Version=${{ steps.gitversion.outputs.nuGetVersionV2 }} \
-                    /p:AssemblyVersion=${{ steps.gitversion.outputs.assemblySemVer }} \
-                    /p:FileVersion=${{ steps.gitversion.outputs.assemblySemFileVer }} \
-                    /p:InformationalVersion=${{ steps.gitversion.outputs.informationalVersion }}
-
-                  # Build DynamicData library
-                  dotnet build R3.DynamicData/R3.DynamicData.csproj --configuration Release --no-restore \
-                    /p:Version=${{ steps.gitversion.outputs.nuGetVersionV2 }} \
-                    /p:AssemblyVersion=${{ steps.gitversion.outputs.assemblySemVer }} \
-                    /p:FileVersion=${{ steps.gitversion.outputs.assemblySemFileVer }} \
-                    /p:InformationalVersion=${{ steps.gitversion.outputs.informationalVersion }}
+                  # Alphabetical sort places R3Ext.Bindings.SourceGenerator before R3Ext (dot < slash),
+                  # so the source generator is always built before the main library that references it.
+                  # dotnet build also resolves project references automatically, so ordering is belt-and-suspenders.
+                  PACKABLE=$(find . -name "*.csproj" -not -path "*/obj/*" | xargs grep -l '<IsPackable>true</IsPackable>' | sort)
+                  for proj in $PACKABLE; do
+                      dotnet build "$proj" --configuration Release --no-restore \
+                        /p:Version=${{ steps.gitversion.outputs.nuGetVersionV2 }} \
+                        /p:AssemblyVersion=${{ steps.gitversion.outputs.assemblySemVer }} \
+                        /p:FileVersion=${{ steps.gitversion.outputs.assemblySemFileVer }} \
+                        /p:InformationalVersion=${{ steps.gitversion.outputs.informationalVersion }}
+                  done
 
             - name: Test
               run: |
                   export DOTNET_USE_SHARED_COMPILATION=false
                   dotnet test R3Ext.Tests/R3Ext.Tests.csproj --configuration Release --verbosity normal
-                  dotnet test R3.DynamicData.Tests/R3.DynamicData.Tests.csproj --configuration Release --verbosity normal
+                  dotnet test R3Ext.DynamicData.Tests/R3Ext.DynamicData.Tests.csproj --configuration Release --verbosity normal
 
             - name: Pack NuGet packages
               run: |
-                  dotnet pack R3Ext/R3Ext.csproj --configuration Release --no-build --output ./artifacts \
-                    /p:PackageVersion=${{ steps.gitversion.outputs.nuGetVersionV2 }}
-
-                  dotnet pack R3Ext.Bindings.SourceGenerator/R3Ext.Bindings.SourceGenerator.csproj --configuration Release --no-build --output ./artifacts \
-                    /p:PackageVersion=${{ steps.gitversion.outputs.nuGetVersionV2 }}
-
-                  dotnet pack R3Ext.Bindings.MauiTargets/R3Ext.Bindings.MauiTargets.csproj --configuration Release --no-build --output ./artifacts \
-                    /p:PackageVersion=${{ steps.gitversion.outputs.nuGetVersionV2 }}
-
-                  dotnet pack R3.DynamicData/R3.DynamicData.csproj --configuration Release --no-build --output ./artifacts \
-                    /p:PackageVersion=${{ steps.gitversion.outputs.nuGetVersionV2 }}
+                  PACKABLE=$(find . -name "*.csproj" -not -path "*/obj/*" | xargs grep -l '<IsPackable>true</IsPackable>' | sort)
+                  for proj in $PACKABLE; do
+                      dotnet pack "$proj" --configuration Release --no-build --output ./artifacts \
+                        /p:PackageVersion=${{ steps.gitversion.outputs.nuGetVersionV2 }}
+                  done
 
             - name: Upload artifacts
               uses: actions/upload-artifact@v4