development

Development Guide

Getting started

1. Install the .NET 10 SDK (the repository pins 10.0.301 in global.json).

2. Clone the repository and build:

   dotnet build CSharp_CHDMounter.sln
   dotnet test CHDMounter.Tests/CHDMounter.Tests.csproj

3. Run the application:

   dotnet run --project CHDMounter/CHDMounter.csproj

See Building from Source for publishing and release packaging.

Repository layout

Path	Contents
CHDMounter/	Cross-platform Avalonia application
CHDMounter/Interfaces/	Service contracts
CHDMounter/Models/	Settings, log entry, mount backend, update result
CHDMounter/Services/	Logging, settings, mounting, screenshots, stats, updates, bug reports
CHDMounter/Mounting/	Mount router, Dokan/WinFsp/FUSE backends, shared path helper
CHDMounter/Views/	Windows, dialogs and code-behind
CHDMounter.Tests/	xUnit unit and integration tests
CHDMounter_Tester/	WPF batch-parsing/benchmarking tool (developer only)
build/	Release packaging script
docs/	This documentation (docfx + GitHub wiki source)

Code conventions

• Nullable reference types are enabled everywhere; avoid ! unless the invariant is obvious and commented.
• Implicit usings are enabled; shared global usings live in GlobalUsings.cs.
• XML documentation is enforced for public API (GenerateDocumentationFile); the solution must build with zero warnings. Document internal helpers too.
• Async naming — every asynchronous method ends with Async, including event handlers.
• Logging goes through Serilog. Never use Console.WriteLine/Debug.WriteLine for diagnostics; use ILoggingService (UI + Serilog) or Serilog.Log directly.
• User/environment errors are logged with LoggingService.LogUserError (Information level) so they never file bug reports; genuine failures use LogError with the exception.
• Analyzers — Meziantou.Analyzer runs on all projects; keep the build warning-free.
• Visibility — implementation classes are internal; only contracts and types needed by the Tester or tests are public (tests and the Tester use InternalsVisibleTo).
• Catch blocks always log; silent catches are only allowed for documented last-resort paths.

Testing

The test project uses xUnit and contains both unit tests and integration tests:

# All tests
dotnet test CHDMounter.Tests/CHDMounter.Tests.csproj

# A single class
dotnet test CHDMounter.Tests/CHDMounter.Tests.csproj --filter "FullyQualifiedName~MountPathHelperTests"

# By namespace
dotnet test CHDMounter.Tests/CHDMounter.Tests.csproj --filter "FullyQualifiedName~CHDMounter.Tests.Services"

• Integration tests (CHDMounter.Tests/Parsers) parse real CHD files. They read paths from ChdPathCatalog; directories that do not exist on the machine are skipped, so the suite passes on machines without the game library.
• Unit tests must not send real bug reports — TestInitializer disables bug reporting for the whole test process, and BugReportClient refuses to send from test hosts.
• Prefer testing pure logic through internal statics (for example MountPathHelper, ScreenshotPaths, FileNameMatcher, DriveHelper, FuseFileSystem.BuildMountArguments).

Debugging tips

• The UI log pane shows the same messages that are written to the daily log file; the newest log is the first thing to inspect.
• Press F8 to capture the current window to the Screenshot folder (see Screenshots).
• Startup failures are logged before the UI exists; run the executable from a terminal to see console output.
• BugReportSink only forwards Warning+ events. To reproduce a bug report locally, enable sending with BugReportClient.IsSendingEnabled = true (production entry points do this) and watch the log file for BugReportClient: messages.

The Tester tool

CHDMounter_Tester is a Windows-only WPF tool for batch-parsing folders of CHD files:

1. Select a folder containing .chd files.
2. Choose a console type.
3. Click Run Tests to parse every file and collect statistics.
4. Click Export PDF to save a report.

It is intentionally not published in releases; build it from source with dotnet run --project CHDMounter_Tester/CHDMounter_Tester.csproj.

Adding support for new console formats

Console file system parsers and the alias registry live in the external VideoGameFileSystemParser package — not in this repository. To add a format, contribute the parser there, then bump the VideoGameFileSystemParser package reference in CHDMounter/CHDMounter.csproj. The alias list shown in the UI and accepted by /s:<alias> updates automatically because it is read from the library's ParserFactory.

Documentation

This documentation lives in docs/. Add a page, link it from docs/index.md, docs/toc.yml and docs/_Sidebar.md, then open a pull request. The docs workflow builds the site with docfx and publishes it to GitHub Pages and the wiki.

See also

• Architecture
• Building from Source
• Privacy and Telemetry