Summary

This PR adds comprehensive support for building and testing Microsoft Identity Web with .NET 10 preview versions using the established conditional compilation pattern with the TargetNetNext=true flag.

What's Changed

🔧 Build System & SDK Configuration

• Updated global.json to support .NET 10 preview SDK (10.0.100-preview.1.25307.7) with allowPrerelease flag
• Added net10.0 to all TargetNetNext conditional framework configurations across the solution
• Added .NET 10 preview dependency versions in Directory.Build.props with proper version constraints
• Updated warning suppression rules to include .NET 10 preview

📦 Project Files Updated

• Main build configuration (Directory.Build.props)
• Test projects configuration (tests/Directory.Build.props)
• DevApps configuration (tests/DevApps/Directory.Build.props)
• Microsoft.Identity.Web.UI project file
• All test project files with TargetNetNext support (integration tests, performance tests, E2E tests, common test libraries)

🚀 CI/CD Pipeline Updates

• Updated GitHub Actions workflow to install .NET 10 preview SDK and run conditional tests
• Updated Azure DevOps build template for .NET 10 preview SDK installation
• Added conditional test execution for .NET 10 with continue-on-error: true for early preview stability

📖 Documentation & Validation

• Updated README.md with .NET 10 preview build instructions
• Updated changelog.md documenting the new feature
• Created validation script to verify proper configuration

Usage

To build and test with .NET 10 preview support:

# Build with .NET 10 preview targets included
dotnet build Microsoft.Identity.Web.sln -p:TargetNetNext=true

# Run tests targeting .NET 10 preview
dotnet test Microsoft.Identity.Web.sln -f net10.0 -p:TargetNetNext=true

Backward Compatibility

✅ All changes are conditional and maintain full backward compatibility. Production builds remain unchanged unless explicitly enabling TargetNetNext=true. This follows the same pattern established for .NET 9 preview support.

Testing

• Validated all project files have proper TargetNetNext configurations
• Verified build system configurations are consistent across the solution
• Confirmed CI/CD pipelines properly handle .NET 10 preview installation
• Created validation script to verify configuration integrity

Related Issues

Addresses the requirement to enable early testing and compatibility validation with the latest .NET preview versions, supporting the community's need to test Microsoft Identity Web against upcoming .NET releases.

💬 Share your feedback on Copilot coding agent for the chance to win a $200 gift card! Click here to start the survey.