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

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

@@ -0,0 +1,71 @@
+using Features.Users.Commands.Account.UpdateUsername;
+using FluentValidation.TestHelper;
+
+namespace Features.Users.Tests.Commands;
+
+public class UpdateUsernameValidatorTests
+{
+    private readonly UpdateUsernameValidator _validator = new();
+
+    private static UpdateUsernameCommand ValidCommand() => new(Guid.NewGuid(), "valid.user-99");
+
+    [Fact]
+    public void Validate_ValidCommand_HasNoValidationErrors()
+    {
+        TestValidationResult<UpdateUsernameCommand> result = _validator.TestValidate(
+            ValidCommand()
+        );
+
+        result.ShouldNotHaveAnyValidationErrors();
+    }
+
+    [Fact]
+    public void Validate_EmptyNewUsername_HasErrorForNewUsername()
+    {
+        UpdateUsernameCommand command = ValidCommand() with { NewUsername = "" };
+
+        TestValidationResult<UpdateUsernameCommand> result = _validator.TestValidate(command);
+
+        result
+            .ShouldHaveValidationErrorFor(x => x.NewUsername)
+            .WithErrorMessage("Username is required");
+    }
+
+    [Fact]
+    public void Validate_NewUsernameTooShort_HasErrorForNewUsername()
+    {
+        UpdateUsernameCommand command = ValidCommand() with { NewUsername = "ab" };
+
+        TestValidationResult<UpdateUsernameCommand> result = _validator.TestValidate(command);
+
+        result
+            .ShouldHaveValidationErrorFor(x => x.NewUsername)
+            .WithErrorMessage("Username must be between 3 and 64 characters");
+    }
+
+    [Fact]
+    public void Validate_NewUsernameTooLong_HasErrorForNewUsername()
+    {
+        UpdateUsernameCommand command = ValidCommand() with { NewUsername = new string('a', 65) };
+
+        TestValidationResult<UpdateUsernameCommand> result = _validator.TestValidate(command);
+
+        result
+            .ShouldHaveValidationErrorFor(x => x.NewUsername)
+            .WithErrorMessage("Username must be between 3 and 64 characters");
+    }
+
+    [Fact]
+    public void Validate_NewUsernameHasDisallowedCharacters_HasErrorForNewUsername()
+    {
+        UpdateUsernameCommand command = ValidCommand() with { NewUsername = "bad user!" };
+
+        TestValidationResult<UpdateUsernameCommand> result = _validator.TestValidate(command);
+
+        result
+            .ShouldHaveValidationErrorFor(x => x.NewUsername)
+            .WithErrorMessage(
+                "Username can only contain letters, numbers, dots, underscores, and hyphens"
+            );
+    }
+}