Fix retrieval of main page when title is explicit

.github/workflows/publish.yml

@@ -1,6 +1,6 @@
 name: publish
 env:
-  VERSION: '0.18.4-preview'
+  VERSION: '0.18.5-preview'
   PRERELEASE: true
 on:
   push:

docs/CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## 0.18.5-preview
+### Fixed
+- Retrieval of main page when title is explicit
+
 ## 0.18.4-preview
 ### Fixed
 - URL generation for main titles

src/Models/PageTitle.cs

@@ -353,16 +353,16 @@ public override string ToString()
     /// Gets a copy of this instance with the specified default title, if <see cref="Title"/> is
     /// currently <see langword="null"/>.
     /// </summary>
-    /// <param name="defaultTitle">
-    /// The domain of the page (if any).
+    /// <param name="title">
+    /// The default title to supply if the currrent title is <see langword="null"/>.
     /// </param>
     /// <returns>
     /// A new <see cref="PageTitle"/> with <see cref="Title"/> set to the given default if it was
     /// previously <see langword="null"/>, and the same <see cref="Namespace"/> and <see
     /// cref="Domain"/> as this instance.
     /// </returns>
-    public PageTitle WithDefaultTitle(string defaultTitle)
-        => new(Title ?? defaultTitle, Namespace, Domain);
+    public PageTitle WithDefaultTitle(string title)
+        => new(Title ?? title, Namespace, Domain);
 
     /// <summary>
     /// Gets a copy of this instance with the specified <paramref name="domain"/>.
@@ -390,6 +390,19 @@ public PageTitle WithDefaultTitle(string defaultTitle)
     /// </returns>
     public PageTitle WithNamespace(string? @namespace) => new(Title, @namespace, Domain);
 
+    /// <summary>
+    /// Gets a copy of this instance with the specified title.
+    /// </summary>
+    /// <param name="title">
+    /// The title of the page (if any).
+    /// </param>
+    /// <returns>
+    /// A new <see cref="PageTitle"/> with <see cref="Title"/> set to the given value, and the same
+    /// <see cref="Namespace"/> and <see cref="Domain"/> as this instance.
+    /// </returns>
+    public PageTitle WithTitle(string? title)
+        => new(title, Namespace, Domain);
+
     internal void WriteUrl(StringWriter writer, WikiOptions wikiOptions)
     {
         if (!string.IsNullOrEmpty(Domain))

src/WikiExtensions.cs

@@ -1218,6 +1218,10 @@ public static async Task<Page> GetWikiPageAsync(
         bool noRedirect = false,
         bool exactMatchOnly = false)
     {
+        if (title.Title?.Equals(options.MainPageTitle) == true)
+        {
+            title = title.WithTitle(null);
+        }
         if (string.CompareOrdinal(title.Namespace, options.CategoryNamespace) == 0)
         {
             return await IPage<Category>