Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/tools/mono-api-html/Comparer.cs

@@ -0,0 +1,98 @@
+// 
+// Authors
+//    Sebastien Pouliot  <sebastien@xamarin.com>
+//
+// Copyright 2013 Xamarin Inc. http://www.xamarin.com
+// 
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+//
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Xml.Linq;
+
+namespace Xamarin.ApiDiff {
+
+	public abstract class Comparer {
+
+		protected List<XElement> removed = new List<XElement> ();
+		protected ApiChanges modified = new ApiChanges ();
+
+		public TextWriter Output {
+			get { return State.Output; }
+		}
+
+		protected TextWriter Indent ()
+		{
+			for (int i = 0; i < State.Indent; i++)
+				State.Output.Write ("\t");
+			return State.Output;
+		}
+
+		public abstract void Added (XElement target, bool wasParentAdded);
+		public abstract void Modified (XElement source, XElement target, ApiChanges changes);
+		public abstract void Removed (XElement source);
+
+		public virtual bool Equals (XElement source, XElement target, ApiChanges changes)
+		{
+			return XNode.DeepEquals (source, target);
+		}
+
+		public abstract void SetContext (XElement current);
+
+		public virtual void Compare (IEnumerable<XElement> source, IEnumerable<XElement> target)
+		{
+			removed.Clear ();
+			modified.Clear ();
+
+			foreach (var s in source) {
+				SetContext (s);
+				string sn = s.GetAttribute ("name");
+				var t = target == null ? null : target.SingleOrDefault (x => x.GetAttribute ("name") == sn);
+				if (t == null) {
+					// not in target, it was removed
+					removed.Add (s);
+				} else {
+					t.Remove ();
+					// possibly modified
+					if (Equals (s, t, modified))
+						continue;
+
+					// still in target so will be part of Added
+					Modified (s, t, modified);
+				}
+			}
+			// delayed, that way we show "Modified", "Added" and then "Removed"
+			foreach (var item in removed) {
+				SetContext (item);
+				Removed (item);
+			}
+			// remaining == newly added in target
+			if (target != null) {
+				foreach (var item in target) {
+					SetContext (item);
+					Added (item, false);
+				}
+			}
+		}
+	}
+}