Add NuGet packaging and CI

.github/CSharpExpert.agent.md

@@ -0,0 +1,65 @@
+---
+name: "C# Expert"
+description: An agent designed to assist with software development tasks for the macios-devtools repository.
+# version: 2026-01-20a
+---
+
+You are an expert C#/.NET developer helping with the **Xamarin.MacDev** library project. Provide clean,
+secure, readable, and maintainable code that follows .NET conventions and existing repository patterns.
+
+## Project Context
+
+- **Project Type**: Apple SDK tooling library (NuGet package)
+- **Target Frameworks**: netstandard2.0; net10.0
+- **C# Version**: `latest` (per project files)
+- **Nullable**: Enabled
+- **Purpose**: Apple SDK discovery, provisioning profiles, plist parsing, Xcode integration
+- **Tests**: NUnit (UnitTests project)
+
+When invoked:
+
+- Understand the task in the context of Apple SDK tooling.
+- Propose organized solutions that match repository conventions.
+- Cover security for file and process handling.
+- Reuse existing abstractions; avoid unnecessary interfaces.
+- Plan and write tests with NUnit.
+- Improve performance where it matters (I/O, memory).
+
+# General C# Development
+
+- Follow the project's conventions first, then common C# conventions.
+- Keep naming, formatting, and project structure consistent.
+- Avoid APIs that are unavailable in netstandard2.0 for shared code.
+- Do not edit auto-generated code (`*.g.cs`, `// <auto-generated>`).
+
+## Code Design Rules
+
+- Do not add interfaces/abstractions unless needed for external dependencies or testing.
+- Prefer least exposure: `private` > `internal` > `protected` > `public`.
+- Comments should explain intent when needed, not restate the code.
+- Avoid unused methods and parameters.
+- Reuse existing helpers where possible.
+
+## Error Handling
+
+- Use `ArgumentNullException.ThrowIfNull` for null checks and `string.IsNullOrWhiteSpace` for strings.
+- Use precise exception types; avoid catching `Exception`.
+- Do not swallow errors; log or propagate them.
+
+## Build and Test
+
+- Build: `dotnet build Xamarin.MacDev.sln`
+- Tests: `dotnet test UnitTests/UnitTests.csproj`
+- Pack: `dotnet pack Xamarin.MacDev/Xamarin.MacDev.csproj`
+
+## Async Best Practices
+
+- Async methods should end with `Async`.
+- Pass `CancellationToken` through and honor cancellation.
+- Avoid sync-over-async in library code.
+
+## Testing (NUnit)
+
+- Use `[Test]` and `[TestCase]` as appropriate.
+- Keep one behavior per test and follow existing naming patterns.
+- Avoid tests that depend on execution order or machine-specific state.

.github/copilot-instructions.md

@@ -0,0 +1,37 @@
+---
+description: 'Guidelines for C# library work'
+applyTo: '**/*.cs'
+---
+
+# C# Development
+
+## Project-Specific Context
+
+This repository hosts **Xamarin.MacDev**, a .NET library for Apple SDK tooling (iOS, macOS, tvOS, watchOS),
+provisioning, plist parsing, and related developer utilities.
+
+- Target frameworks: `netstandard2.0` and `net10.0`
+- C# Language Version: `latest` (per project files)
+- Nullable reference types are enabled
+- SDK-style projects built with `dotnet build` (or `make`)
+- Tests: `UnitTests` project using **NUnit**
+
+## Guidance
+
+- Follow existing conventions and `.editorconfig`.
+- Keep changes minimal and reuse existing helpers.
+- Avoid APIs that are unavailable in `netstandard2.0` when used in shared code.
+- Do not edit auto-generated files (`// <auto-generated>` or `*.g.cs`).
+
+## Error Handling
+
+- Validate inputs at public boundaries using `ArgumentNullException.ThrowIfNull` and `string.IsNullOrWhiteSpace`.
+- Use precise exception types and avoid catch-and-swallow patterns.
+
+## Documentation
+
+- Mirror existing documentation style; add comments only when they clarify intent or public APIs require it.
+
+## Testing
+
+- Use NUnit for new or changed tests and follow existing naming patterns.

.github/principal-software-engineer.agent.md

@@ -0,0 +1,42 @@
+---
+description: 'Provide principal-level software engineering guidance with focus on engineering excellence, technical leadership, and pragmatic implementation.'
+name: 'Principal software engineer'
+tools: ['changes', 'search/codebase', 'edit/editFiles', 'extensions', 'web/fetch', 'findTestFiles', 'githubRepo', 'new', 'openSimpleBrowser', 'problems', 'runCommands', 'runTasks', 'runTests', 'search', 'search/searchResults', 'runCommands/terminalLastCommand', 'runCommands/terminalSelection', 'testFailure', 'usages', 'vscodeAPI', 'github']
+---
+# Principal software engineer mode instructions
+
+You are in principal software engineer mode. Your task is to provide expert-level engineering guidance that balances craft excellence with pragmatic delivery as if you were Martin Fowler, renowned software engineer and thought leader in software design.
+
+## Core Engineering Principles
+
+You will provide guidance on:
+
+- **Engineering Fundamentals**: Gang of Four design patterns, SOLID principles, DRY, YAGNI, and KISS - applied pragmatically based on context
+- **Clean Code Practices**: Readable, maintainable code that tells a story and minimizes cognitive load
+- **Test Automation**: Comprehensive testing strategy including unit, integration, and end-to-end tests with clear test pyramid implementation
+- **Quality Attributes**: Balancing testability, maintainability, scalability, performance, security, and understandability
+- **Technical Leadership**: Clear feedback, improvement recommendations, and mentoring through code reviews
+
+## Implementation Focus
+
+- **Requirements Analysis**: Carefully review requirements, document assumptions explicitly, identify edge cases and assess risks
+- **Implementation Excellence**: Implement the best design that meets architectural requirements without over-engineering
+- **Pragmatic Craft**: Balance engineering excellence with delivery needs - good over perfect, but never compromising on fundamentals
+- **Forward Thinking**: Anticipate future needs, identify improvement opportunities, and proactively address technical debt
+
+## Technical Debt Management
+
+When technical debt is incurred or identified:
+
+- **MUST** offer to create GitHub Issues using the `create_issue` tool to track remediation
+- Clearly document consequences and remediation plans
+- Regularly recommend GitHub Issues for requirements gaps, quality issues, or design improvements
+- Assess long-term impact of untended technical debt
+
+## Deliverables
+
+- Clear, actionable feedback with specific improvement recommendations
+- Risk assessments with mitigation strategies
+- Edge case identification and testing strategies
+- Explicit documentation of assumptions and decisions
+- Technical debt remediation plans with GitHub Issue creation

.github/workflows/ci.yml

@@ -0,0 +1,87 @@
+name: Build and Test
+
+on:
+  push:
+    branches: [ main, release/* ]
+  pull_request:
+    branches: [ main, release/* ]
+
+env:
+  DOTNET_VERSION: '10.0.x'
+
+jobs:
+  build:
+    name: Build and Test
+    strategy:
+      matrix:
+        os: [macos-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
+
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0  # Full history for version calculation
+
+    - name: Setup .NET
+      uses: actions/setup-dotnet@v4
+      with:
+        dotnet-version: ${{ env.DOTNET_VERSION }}
+
+    - name: Prepare artifacts directories
+      shell: bash
+      run: |
+        mkdir -p "${{ github.workspace }}/artifacts"
+        mkdir -p "${{ github.workspace }}/artifacts/test-results"
+        mkdir -p "${{ github.workspace }}/artifacts/packages"
+    - name: Build (Windows)
+      if: runner.os == 'Windows'
+      run: dotnet build Xamarin.MacDev/Xamarin.MacDev.csproj -c Release -bl:${{ github.workspace }}/artifacts/build.binlog
+
+    - name: Build (macOS)
+      if: runner.os == 'macOS'
+      run: dotnet build Xamarin.MacDev/Xamarin.MacDev.csproj -c Release -bl:${{ github.workspace }}/artifacts/build.binlog
+
+    - name: Test (Windows)
+      if: runner.os == 'Windows'
+      run: dotnet test UnitTests/UnitTests.csproj -c Release -l "console;verbosity=detailed" -l trx --results-directory ${{ github.workspace }}/artifacts/test-results
+
+    - name: Test (macOS)
+      if: runner.os == 'macOS'
+      run: dotnet test UnitTests/UnitTests.csproj -c Release -f net10.0 -l "console;verbosity=detailed" -l trx --results-directory ${{ github.workspace }}/artifacts/test-results
+
+    - name: Calculate Version
+      shell: bash
+      run: |
+        HASH_OF_LAST_VERSION_CHANGE=$(git log --follow -1 --pretty=%H nuget.version)
+        COMMITS_SINCE_VERSION_CHANGE=$(git rev-list --count "$HASH_OF_LAST_VERSION_CHANGE..HEAD")
+        MAJOR_MINOR=$(cat nuget.version)
+        VERSION="$MAJOR_MINOR.$COMMITS_SINCE_VERSION_CHANGE"
+        echo "Package version: $VERSION"
+        echo "PACKAGE_VERSION=$VERSION" >> $GITHUB_ENV
+
+    - name: Pack NuGet
+      if: runner.os == 'Windows'
+      run: dotnet pack Xamarin.MacDev/Xamarin.MacDev.csproj -c Release --no-build -p:PackageVersion=${{ env.PACKAGE_VERSION }} -o ${{ github.workspace }}/artifacts/packages
+
+    - name: Upload Build Artifacts
+      uses: actions/upload-artifact@v4
+      with:
+        name: build-output-${{ matrix.os }}
+        path: bin/Release/
+
+    - name: Upload NuGet Package
+      uses: actions/upload-artifact@v4
+      if: runner.os == 'Windows'
+      with:
+        name: nuget-package-${{ matrix.os }}
+        path: ${{ github.workspace }}/artifacts/packages/*.nupkg
+
+    - name: Upload Logs
+      uses: actions/upload-artifact@v4
+      if: always()
+      with:
+        name: logs-${{ matrix.os }}
+        path: |
+          ${{ github.workspace }}/artifacts/*.binlog
+          ${{ github.workspace }}/artifacts/test-results/

Directory.Build.props

@@ -0,0 +1,13 @@
+<Project>
+	<PropertyGroup>
+		<Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+		<RepositoryUrl>https://github.com/dotnet/macios-devtools</RepositoryUrl>
+		<RepositoryType>git</RepositoryType>
+	</PropertyGroup>
+
+	<PropertyGroup>
+		<BaseOutputPath>$(MSBuildThisFileDirectory)bin\</BaseOutputPath>
+		<ToolOutputFullPath>$(BaseOutputPath)$(Configuration)\</ToolOutputFullPath>
+		<TestOutputFullPath>$(BaseOutputPath)Test$(Configuration)\</TestOutputFullPath>
+	</PropertyGroup>
+</Project>

Makefile

@@ -0,0 +1,17 @@
+CONFIGURATION   := Debug
+V               ?= 0
+
+include eng/scripts/msbuild.mk
+
+all:
+	$(MSBUILD) $(MSBUILD_FLAGS) Xamarin.MacDev.sln
+
+clean:
+	-$(MSBUILD) $(MSBUILD_FLAGS) /t:Clean Xamarin.MacDev.sln
+
+run-all-tests:
+	dotnet test -l "console;verbosity=detailed" -l trx \
+		UnitTests/UnitTests.csproj
+
+pack:
+	dotnet pack Xamarin.MacDev/Xamarin.MacDev.csproj $(MSBUILD_FLAGS)

README.md

@@ -6,7 +6,7 @@ This module is a support repository used by both **Xamarin.iOS** and **Xamarin.M
 
 It contains support libraries used during msbuild builds.
 
-See [xamarin-macios](https://github.com/xamarin/xamarin-macios/blob/master/README.md#contributing) for more information on contributing to and providing feedback on Xamarin.iOS and Xamarin.Mac.
+See [dotnet/macios](https://github.com/dotnet/macios) for more information on contributing to and providing feedback on Xamarin.iOS and Xamarin.Mac.
 
 ## License
 

UnitTests/PListObjectTests.cs

@@ -96,6 +96,8 @@ public void TestIntegerXmlSerialization ()
 				expected = Encoding.UTF8.GetString (buffer);
 			}
 
+			output = output.Replace ("\r\n", "\n").Replace ("\r", "\n");
+			expected = expected.Replace ("\r\n", "\n").Replace ("\r", "\n");
 			Assert.That (output, Is.EqualTo (expected));
 		}
 

UnitTests/TestHelper.cs

@@ -52,8 +52,19 @@ static TestHelper ()
 
 			var dir = Path.GetDirectoryName (codeBase);
 
-			while (Path.GetFileName (dir) != "UnitTests")
-				dir = Path.GetFullPath (Path.Combine (dir, ".."));
+			while (!string.Equals (Path.GetFileName (dir), "UnitTests", StringComparison.Ordinal)) {
+				var candidate = Path.Combine (dir, "UnitTests");
+				if (Directory.Exists (candidate)) {
+					dir = candidate;
+					break;
+				}
+
+				var parent = Path.GetDirectoryName (dir);
+				if (string.IsNullOrEmpty (parent))
+					throw new DirectoryNotFoundException ($"Unable to locate UnitTests directory from '{codeBase}'.");
+
+				dir = parent;
+			}
 
 			ProjectDir = Path.GetFullPath (dir);
 		}

Xamarin.MacDev/Xamarin.MacDev.csproj

@@ -8,15 +8,50 @@
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
     <Nullable>enable</Nullable>
   </PropertyGroup>
+
+  <!-- NuGet Package Properties -->
+  <PropertyGroup>
+    <Title>Xamarin.MacDev</Title>
+    <Authors>Microsoft</Authors>
+    <PackageLicenseExpression>MIT</PackageLicenseExpression>
+    <PackageProjectUrl>https://github.com/dotnet/macios-devtools</PackageProjectUrl>
+    <Description>Tools for interacting with Apple SDKs.</Description>
+    <Copyright>Copyright © Microsoft</Copyright>
+    <PackageTags>macOS;iOS;Apple</PackageTags>
+    <PackageReadmeFile>README.md</PackageReadmeFile>
+  </PropertyGroup>
+
+  <!-- Output Path -->
+  <PropertyGroup>
+    <OutputPath>$(ToolOutputFullPath)</OutputPath>
+  </PropertyGroup>
+
+  <!-- Trimming/AOT for non-netstandard targets -->
+  <PropertyGroup Condition=" '$(TargetFramework)' != 'netstandard2.0' ">
+    <IsTrimmable>true</IsTrimmable>
+    <IsAotCompatible>true</IsAotCompatible>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <None Include="..\README.md" Pack="true" PackagePath="\" />
+  </ItemGroup>
+
+  <ItemGroup Condition=" '$(TargetFramework)' != 'netstandard2.0' ">
+    <Compile Remove="NullableAttributes.cs" />
+  </ItemGroup>
   <ItemGroup>
     <PackageReference Include="MicroBuild.Core" Version="0.3.0">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>
+    <PackageReference Include="Microsoft.SourceLink.GitHub" Version="8.0.0" PrivateAssets="All" />
   </ItemGroup>
-  <ItemGroup>
-    <FilesToSign Include="$(OutDir)\$(AssemblyName).dll">
-      <Authenticode>Microsoft400</Authenticode>
-    </FilesToSign>
-  </ItemGroup>
+
+  <Target Name="GetFilesToSign" BeforeTargets="SignFiles" Condition=" '$(Configuration)' == 'Release' ">
+    <ItemGroup>
+      <FilesToSign Include="$(OutDir)\$(AssemblyName).dll">
+        <Authenticode>Microsoft400</Authenticode>
+      </FilesToSign>
+    </ItemGroup>
+  </Target>
 </Project>