Reorganize tests by API and service concerns

RpgRoller.Tests/Services/ServiceAuthTests.cs

@@ -0,0 +1,59 @@
+namespace RpgRoller.Tests;
+
+public sealed class ServiceAuthTests
+{
+    [Fact]
+    public void Register_ValidatesRequiredFieldsAndDuplicates()
+    {
+        using var harness = ServiceTestSupport.CreateHarness();
+        var service = harness.Service;
+
+        var invalidUsername = service.Register(new RegisterCommand("", "Password123", "Display"));
+        var invalidDisplay = service.Register(new RegisterCommand("user", "Password123", ""));
+        var invalidPassword = service.Register(new RegisterCommand("user", "short", "Display"));
+        var valid = service.Register(new RegisterCommand("user", "Password123", "Display"));
+        var duplicate = service.Register(new RegisterCommand("user", "Password123", "Display 2"));
+
+        Assert.False(invalidUsername.Succeeded);
+        Assert.False(invalidDisplay.Succeeded);
+        Assert.False(invalidPassword.Succeeded);
+        Assert.True(valid.Succeeded);
+        Assert.False(duplicate.Succeeded);
+    }
+
+    [Fact]
+    public void Login_ValidatesCredentialsAndSessionLookup()
+    {
+        using var harness = ServiceTestSupport.CreateHarness();
+        var service = harness.Service;
+        service.Register(new RegisterCommand("user", "Password123", "Display"));
+
+        var invalidUser = service.Login(new LoginCommand("missing", "Password123"));
+        var invalidPassword = service.Login(new LoginCommand("user", "bad-password"));
+        var valid = service.Login(new LoginCommand("user", "Password123"));
+
+        Assert.False(invalidUser.Succeeded);
+        Assert.False(invalidPassword.Succeeded);
+        Assert.True(valid.Succeeded);
+
+        var sessionUser = service.GetUserBySession(valid.Value.SessionToken);
+        Assert.NotNull(sessionUser);
+
+        service.Logout(valid.Value.SessionToken);
+        Assert.Null(service.GetUserBySession(valid.Value.SessionToken));
+    }
+
+    [Fact]
+    public void Login_RehashesPasswordWhenHasherRequestsIt()
+    {
+        var hasher = new ServiceTestSupport.RehashingPasswordHasher();
+        using var harness = ServiceTestSupport.CreateHarness(hasher);
+        var service = harness.Service;
+
+        service.Register(new RegisterCommand("user", "Password123", "Display"));
+        var login = service.Login(new LoginCommand("user", "Password123"));
+
+        Assert.True(login.Succeeded);
+        Assert.Equal(2, hasher.HashCalls);
+    }
+}