test: add component behavior coverage

- add lightweight component test runner

- cover markdown loader select list and editor behavior

test/TinyTUI.Tests/Program.cs

@@ -0,0 +1,121 @@
+using TinyTUI.Components;
+using TinyTUI.Input;
+
+var tests = new (string Name, Action Test)[]
+{
+    ("Markdown renders supported block markers", MarkdownRendersSupportedBlockMarkers),
+    ("Loader cycles frames", LoaderCyclesFrames),
+    ("SelectList handles navigation and submit", SelectListHandlesNavigationAndSubmit),
+    ("Editor handles unicode text and backspace", EditorHandlesUnicodeTextAndBackspace),
+    ("Editor handles multiline editing", EditorHandlesMultilineEditing),
+};
+
+var failed = 0;
+
+foreach (var (name, test) in tests)
+{
+    try
+    {
+        test();
+        Console.WriteLine($"PASS {name}");
+    }
+    catch (Exception ex)
+    {
+        failed++;
+        Console.WriteLine($"FAIL {name}");
+        Console.WriteLine(ex.Message);
+    }
+}
+
+if (failed > 0)
+    return failed;
+
+Console.WriteLine($"PASS {tests.Length} tests");
+return 0;
+
+static void MarkdownRendersSupportedBlockMarkers()
+{
+    var markdown = new Markdown(
+        "# title\n" +
+        "## subtitle\n" +
+        "- item\n" +
+        "> quote\n" +
+        "plain **bold** and `code`");
+
+    var lines = markdown.Render(80);
+
+    AssertEqual("TITLE", lines[0]);
+    AssertEqual("SUBTITLE", lines[1]);
+    AssertEqual("* item", lines[2]);
+    AssertEqual("| quote", lines[3]);
+    AssertEqual("plain bold and code", lines[4]);
+}
+
+static void LoaderCyclesFrames()
+{
+    var loader = new Loader { Message = "work", Frames = ["a", "b"] };
+
+    AssertEqual("a work", loader.Render(80)[0]);
+
+    loader.Tick();
+    AssertEqual("b work", loader.Render(80)[0]);
+
+    loader.Tick();
+    AssertEqual("a work", loader.Render(80)[0]);
+}
+
+static void SelectListHandlesNavigationAndSubmit()
+{
+    var submitted = string.Empty;
+    var submittedIndex = -1;
+    var select = new SelectList { Height = 2 };
+
+    select.SetItems(["one", "two", "three"]);
+    select.OnSubmitted = (item, index) =>
+    {
+        submitted = item;
+        submittedIndex = index;
+    };
+
+    select.HandleInput(Key(KeyNames.Down));
+    select.HandleInput(Key(KeyNames.Down));
+    select.HandleInput(Key(KeyNames.Down));
+    select.HandleInput(Key(KeyNames.Enter));
+
+    AssertEqual(2, select.SelectedIndex);
+    AssertEqual("three", submitted);
+    AssertEqual(2, submittedIndex);
+    AssertEqual("> three", select.Render(80)[1]);
+}
+
+static void EditorHandlesUnicodeTextAndBackspace()
+{
+    var editor = new Editor();
+
+    editor.HandleInput(Text("a😀"));
+    editor.HandleInput(Key(KeyNames.Backspace));
+
+    AssertEqual("a", editor.Value);
+}
+
+static void EditorHandlesMultilineEditing()
+{
+    var editor = new Editor();
+
+    editor.HandleInput(Text("abc"));
+    editor.HandleInput(Key(KeyNames.Left));
+    editor.HandleInput(Key(KeyNames.Enter));
+    editor.HandleInput(Text("x"));
+
+    AssertEqual("ab\nxc", editor.Value);
+}
+
+static TuiInputEvent Text(string value) => new(TuiInputEventKind.Text, value);
+
+static TuiInputEvent Key(string value) => new(TuiInputEventKind.Key, value);
+
+static void AssertEqual<T>(T expected, T actual)
+{
+    if (!EqualityComparer<T>.Default.Equals(expected, actual))
+        throw new InvalidOperationException($"Expected: {expected}{Environment.NewLine}Actual:   {actual}");
+}

test/TinyTUI.Tests/TinyTUI.Tests.csproj

@@ -0,0 +1,14 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\src\TinyTUI\TinyTUI.csproj" />
+  </ItemGroup>
+
+</Project>

ttui.slnx

@@ -9,4 +9,5 @@
   </Folder>
   <Project Path="src/Example/Example.csproj" Id="6656c1ec-b220-4e7a-8875-5a97a85afbc1" />
   <Project Path="src/TinyTUI/TinyTUI.csproj" Id="f39199aa-6947-4951-b952-a1588045505e" />
+  <Project Path="test/TinyTUI.Tests/TinyTUI.Tests.csproj" />
 </Solution>