Create GovUkPaginationTagHelperTests.cs

Childrens-Social-Care-CPD-Tests/TagHelpers/GovUkPaginationTagHelperTests.cs

@@ -0,0 +1,199 @@
+using Childrens_Social_Care_CPD.TagHelpers;
+using FluentAssertions;
+using Microsoft.AspNetCore.Razor.TagHelpers;
+using Microsoft.Extensions.WebEncoders.Testing;
+using NUnit.Framework;
+using System.Collections.Generic;
+using System.IO;
+using System.Text.Encodings.Web;
+using System.Text.RegularExpressions;
+using System.Threading.Tasks;
+
+namespace Childrens_Social_Care_CPD_Tests.TagHelpers;
+
+public class GovUkPaginationTagHelperTests
+{
+    private TagHelperContext _tagHelperContext;
+    private TagHelperOutput _tagHelperOutput;
+
+    [SetUp]
+    public void SetUp()
+    {
+        static Task<TagHelperContent> func(bool result, HtmlEncoder encoder)
+        {
+            var tagHelperContent = new DefaultTagHelperContent();
+            tagHelperContent.SetHtmlContent(string.Empty);
+            return Task.FromResult<TagHelperContent>(tagHelperContent);
+        }
+
+        _tagHelperContext = new TagHelperContext(new TagHelperAttributeList(), new Dictionary<object, object>(), "id");
+        _tagHelperOutput = new TagHelperOutput("govuk-pagination", new TagHelperAttributeList(), func);
+    }
+
+    [Test]
+    public void Outputs_Nothing_When_No_Pages()
+    {
+        // arrange
+        var tagHelper = new GovUkPaginationTagHelper
+        {
+            PageCount = 0
+        };
+
+        // act
+        tagHelper.Process(_tagHelperContext, _tagHelperOutput);
+
+        // assert
+        _tagHelperOutput.TagName.Should().Be(null);
+        _tagHelperOutput.Content.IsEmptyOrWhiteSpace.Should().Be(true);
+    }
+
+    [Test]
+    public void Should_Be_A_Nav()
+    {
+        // arrange
+        var tagHelper = new GovUkPaginationTagHelper
+        {
+            PageCount = 1,
+            CurrentPage =1,
+            UrlFormatString = "{0}"
+        };
+
+        // act
+        tagHelper.Process(_tagHelperContext, _tagHelperOutput);
+
+        // assert
+        _tagHelperOutput.TagName.Should().Be("nav");
+    }
+
+
+    [TestCase(1)]
+    [TestCase(2)]
+    public void Should_Highlight_Current_Page(int currentPage)
+    {
+        // arrange
+        var stringWriter = new StringWriter();
+        var tagHelper = new GovUkPaginationTagHelper
+        {
+            PageCount = 2,
+            CurrentPage = currentPage,
+            UrlFormatString = "{0}"
+        };
+        var regex = new Regex("<a[^>]*>HtmlEncode\\[\\[" + currentPage + "\\]\\]<\\/a>");
+
+        // act
+        tagHelper.Process(_tagHelperContext, _tagHelperOutput);
+        _tagHelperOutput.WriteTo(stringWriter, new HtmlTestEncoder());
+        var actual = stringWriter.ToString();
+        var match = regex.Match(actual);
+
+        // assert
+        match.Value.Should().Contain("current");
+    }
+
+    [Test]
+    public void Should_Not_Highlight_Next_Page()
+    {
+        // arrange
+        var stringWriter = new StringWriter();
+        var tagHelper = new GovUkPaginationTagHelper
+        {
+            PageCount = 2,
+            CurrentPage = 1,
+            UrlFormatString = "{0}"
+        };
+        var regex = new Regex("<a[^>]*>HtmlEncode\\[\\[2\\]\\]<\\/a>");
+
+        // act
+        tagHelper.Process(_tagHelperContext, _tagHelperOutput);
+        _tagHelperOutput.WriteTo(stringWriter, new HtmlTestEncoder());
+        var actual = stringWriter.ToString();
+        var match = regex.Match(actual);
+
+        // assert
+        match.Value.Should().NotContain("current");
+    }
+
+    [Test]
+    public void Shows_Next_Link()
+    {
+        // arrange
+        var stringWriter = new StringWriter();
+        var tagHelper = new GovUkPaginationTagHelper
+        {
+            PageCount = 2,
+            CurrentPage = 1,
+            UrlFormatString = "{0}"
+        };
+
+        // act
+        tagHelper.Process(_tagHelperContext, _tagHelperOutput);
+        _tagHelperOutput.WriteTo(stringWriter, new HtmlTestEncoder());
+        var actual = stringWriter.ToString();
+
+        // assert
+        actual.Should().Contain("HtmlEncode[[Next]]");
+    }
+
+    [Test]
+    public void Does_Not_Show_Previous_Link_On_First_Page()
+    {
+        // arrange
+        var stringWriter = new StringWriter();
+        var tagHelper = new GovUkPaginationTagHelper
+        {
+            PageCount = 2,
+            CurrentPage = 1,
+            UrlFormatString = "{0}"
+        };
+
+        // act
+        tagHelper.Process(_tagHelperContext, _tagHelperOutput);
+        _tagHelperOutput.WriteTo(stringWriter, new HtmlTestEncoder());
+        var actual = stringWriter.ToString();
+
+        // assert
+        actual.Should().NotContain("HtmlEncode[[Previous]]");
+    }
+
+    [Test]
+    public void Shows_Previous_Link()
+    {
+        // arrange
+        var stringWriter = new StringWriter();
+        var tagHelper = new GovUkPaginationTagHelper
+        {
+            PageCount = 2,
+            CurrentPage = 2,
+            UrlFormatString = "{0}"
+        };
+
+        // act
+        tagHelper.Process(_tagHelperContext, _tagHelperOutput);
+        _tagHelperOutput.WriteTo(stringWriter, new HtmlTestEncoder());
+        var actual = stringWriter.ToString();
+
+        // assert
+        actual.Should().Contain("HtmlEncode[[Previous]]");
+    }
+
+    [Test]
+    public void Does_Not_Show_Next_Link_On_Last_Page()
+    {
+        // arrange
+        var stringWriter = new StringWriter();
+        var tagHelper = new GovUkPaginationTagHelper
+        {
+            PageCount = 2,
+            CurrentPage = 2,
+            UrlFormatString = "{0}"
+        };
+
+        // act
+        tagHelper.Process(_tagHelperContext, _tagHelperOutput);
+        _tagHelperOutput.WriteTo(stringWriter, new HtmlTestEncoder());
+        var actual = stringWriter.ToString();
+
+        // assert
+        actual.Should().NotContain("HtmlEncode[[Next]]");
+    }
+}