1 files changed, 46 insertions, 0 deletions
diff --git a/src/DotNetOpenAuth.OpenId.RelyingParty.UI/OpenId/RelyingParty/SelectorButtonContract.cs b/src/DotNetOpenAuth.OpenId.RelyingParty.UI/OpenId/RelyingParty/SelectorButtonContract.cs
new file mode 100644
index 0000000..c70218a
--- /dev/null
+++ b/src/DotNetOpenAuth.OpenId.RelyingParty.UI/OpenId/RelyingParty/SelectorButtonContract.cs
@@ -0,0 +1,46 @@
+//-----------------------------------------------------------------------
+// <copyright file="SelectorButtonContract.cs" company="Andrew Arnott">
+//     Copyright (c) Andrew Arnott. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOpenAuth.OpenId.RelyingParty {
+	using System;
+	using System.Diagnostics.Contracts;
+	using System.Web.UI;
+
+	/// <summary>
+	/// The contract class for the <see cref="SelectorButton"/> class.
+	/// </summary>
+	[ContractClassFor(typeof(SelectorButton))]
+	internal abstract class SelectorButtonContract : SelectorButton {
+		/// <summary>
+		/// Ensures that this button has been initialized to a valid state.
+		/// </summary>
+		/// <remarks>
+		/// This is "internal" -- NOT "protected internal" deliberately.  It makes it impossible
+		/// to derive from this class outside the assembly, which suits our purposes since the
+		/// <see cref="OpenIdSelector"/> control is not designed for an extensible set of button types.
+		/// </remarks>
+		internal override void EnsureValid() {
+		}
+
+		/// <summary>
+		/// Renders the leading attributes for the LI tag.
+		/// </summary>
+		/// <param name="writer">The writer.</param>
+		protected internal override void RenderLeadingAttributes(HtmlTextWriter writer) {
+			Contract.Requires<ArgumentNullException>(writer != null);
+		}
+
+		/// <summary>
+		/// Renders the content of the button.
+		/// </summary>
+		/// <param name="writer">The writer.</param>
+		/// <param name="selector">The containing selector control.</param>
+		protected internal override void RenderButtonContent(HtmlTextWriter writer, OpenIdSelector selector) {
+			Contract.Requires<ArgumentNullException>(writer != null);
+			Contract.Requires<ArgumentNullException>(selector != null);
+		}
+	}
+}