Testing channel integrations

Use portable tests for application logic and native consumers for bridge, loading, and packaging behavior. Passing one layer does not establish that the other works.

Run a channel entirely in .NET

Reference NativeChannels.Core in a .NET 10 test or console project. This complete console example creates two endpoints, registers a handler, and performs a typed call:

using NativeChannels;

var pair = InMemoryTransport.CreatePair();
await using var client = new ChannelService(new BinaryMessenger(pair.Managed));
await using var server = new ChannelService(new BinaryMessenger(pair.Native));
using var incoming = server.GetMethodChannel("calculator");
using var registration = incoming.SetMethodCallHandler((call, cancellation) =>
{
    cancellation.ThrowIfCancellationRequested();
    if (call.Method != "add") throw new MethodNotImplementedException(call.Method);
    var sum = call.GetArgument<int>("a") + call.GetArgument<int>("b");
    return ValueTask.FromResult<object?>(sum);
});

using var outgoing = client.GetMethodChannel("calculator");
var result = await outgoing.InvokeAsync<int>("add", new Dictionary<string, object?>
{
    ["a"] = 10,
    ["b"] = 20
});
Console.WriteLine(result); // 30

The services own their messengers and transports. Handles and registrations dispose first because of their declaration order. This exercises the actual managed messenger and codec without MAUI.

Test application behavior

Cover successful values and null, unknown methods, structured errors, cancellation, and feature cleanup. Retain handler tokens until the test finishes. Use a completion signal when a test must wait for handler entry instead of relying on a short sleep. For deadline races, inject a controlled TimeProvider into BinaryMessenger; a real 1 ms deadline can expire before a slow runner dispatches anything.

The repository's portable suite runs with:

bash eng/dotnet.sh test -c Release

For repeated lifecycle stress and optional benchmarks, see performance. Package metadata regression tests use only Python's standard library:

python3 -m unittest discover -s tests/packaging

Verify the native boundary

Use the package-only sample after changing a bridge, binding, native dependency, or packaging rule. Restore into a fresh package cache and rebuild clean consumer outputs. The scripts verify source mapping, archive hashes, and absence of project references.

Run Release consumers on Android and iOS simulators to exercise shrinking/linking and actual framework loading. Compile device/Catalyst targets separately and record runtime execution separately. Shared C#, Kotlin, and Swift protocol fixtures live in tests/fixtures/values.json.

See building for native test commands and verification for recorded results and CI evidence.

Verify a reusable plugin

The currency sample references only Plugin.Maui.Currency. Its AAR and XCFramework arrive through the package's buildTransitive imports. Run its fresh-cache restore and Release runtime checks after changing the plugin, its native modules, or packaging. plugins/Plugin.Maui.Currency/eng/inspect-package.py checks the native classes, preservation rules, framework slices, dependencies, and import paths inside the actual archive.

The portable solution includes 14 currency facade tests, alongside core channel tests. The facade tests compile the production C# source without MAUI workloads; the native app checks remain necessary to establish native loading and real platform results.

The message/event tests cover null versus empty payloads, strict UTF-8, bidirectional replies, registration ownership, independent enumerations, bounded overflow policies, buffered terminal errors, service/handle cancellation, and cleanup after typed conversion failures. Native tests additionally exercise the producer queue and its one-shot termination cleanup. The MAUI sample repeats the message/stream contract through actual packaged Kotlin and Swift adapters.

Native view lifecycle

Portable tests exercise view-channel ownership, cooperative cancellation, isolated instances, and registration cleanup. The package-only sample additionally creates actual native views, checks creation parameters and bidirectional clicks, unloads/reloads a view, rejects background reconnect, and verifies fresh instance IDs and stale-channel failure. Both Android and Apple verification scripts require the native views: result. Native UI and framework loading still require platform execution.