Add validator tests for brewery and user commands (#282)

web/backend/Features/Features.Users.Tests/Commands/LoginValidatorTests.cs

@@ -0,0 +1,39 @@
+using Features.Users.Commands.Authentication.Login;
+using FluentValidation.TestHelper;
+
+namespace Features.Users.Tests.Commands;
+
+public class LoginValidatorTests
+{
+    private readonly LoginValidator _validator = new();
+
+    private static LoginCommand ValidCommand() => new("valid.user-99", "Password1!");
+
+    [Fact]
+    public void Validate_ValidCommand_HasNoValidationErrors()
+    {
+        TestValidationResult<LoginCommand> result = _validator.TestValidate(ValidCommand());
+
+        result.ShouldNotHaveAnyValidationErrors();
+    }
+
+    [Fact]
+    public void Validate_EmptyUsername_HasErrorForUsername()
+    {
+        LoginCommand command = ValidCommand() with { Username = "" };
+
+        TestValidationResult<LoginCommand> result = _validator.TestValidate(command);
+
+        result.ShouldHaveValidationErrorFor(x => x.Username).WithErrorMessage("Username is required");
+    }
+
+    [Fact]
+    public void Validate_EmptyPassword_HasErrorForPassword()
+    {
+        LoginCommand command = ValidCommand() with { Password = "" };
+
+        TestValidationResult<LoginCommand> result = _validator.TestValidate(command);
+
+        result.ShouldHaveValidationErrorFor(x => x.Password).WithErrorMessage("Password is required");
+    }
+}