feat: multidivert; more tests

InkBlot.Tests/Helpers.cs

@@ -1,4 +1,5 @@
 using System.Text;
+using InkBlot.ParseHierarchy;
 using Microsoft.Extensions.Logging;
 
 namespace InkBlot.Tests;
@@ -22,4 +23,20 @@ internal static class Helpers
         var loggerFactory = LoggerFactory.Create(builder => builder.AddConsole());
         return loggerFactory;
     }
+}
+
+public class TestBase
+{
+    protected (Story, Diagnostic[]) ParseText(string inkInput)
+    {
+        // parse the story
+        var fileReader = new InMemoryFileReader([
+            ("main.ink", inkInput)
+        ]);
+        using var loggerFactory = Helpers.GetLoggerFactory();
+        var (story, diagnosticsEnumerable) = InkBlotParser.Parse(fileReader, loggerFactory, "main.ink");
+        var diagnostics = diagnosticsEnumerable.ToArray();
+
+        return (story, diagnostics);
+    }
 }