Remove unnecessary IEquatable implementations

comparison operators, overloads, etc.
These were left over from thinking about the original algorithm.

Author: nslottow

src/Microsoft.DotNet.DeadRegionAnalysis/AnalysisEngine.RegionRemoval.cs

@@ -155,13 +155,7 @@ private static string GetReplacementText(DirectiveTriviaSyntax startDirective, D
 
         private static int CompareTextChanges(TextChange x, TextChange y)
         {
-            int result = x.Span.End - y.Span.End;
-            if (result == 0)
-            {
-                return x.Span.Start - y.Span.Start;
-            }
-
-            return result;
+            return x.Span.CompareTo(y.Span);
         }
 
         private static List<TextChange> MergeOverlappingRegions(List<TextChange> changes)

src/Microsoft.DotNet.DeadRegionAnalysis/ConditionalRegion.cs

@@ -11,7 +11,7 @@
 
 namespace Microsoft.DotNet.DeadRegionAnalysis
 {
-    public class ConditionalRegion : IComparable<ConditionalRegion>, IEquatable<ConditionalRegion>
+    public class ConditionalRegion : IComparable<ConditionalRegion>
     {
         public DirectiveTriviaSyntax StartDirective { get; private set; }
 
@@ -61,7 +61,7 @@ public int CompareTo(ConditionalRegion other)
         {
             if (other == null)
             {
-                return 1;
+                return -1;
             }
 
             int result = SpanStart - other.SpanStart;
@@ -73,41 +73,6 @@ public int CompareTo(ConditionalRegion other)
             return result;
         }
 
-        public bool Equals(ConditionalRegion other)
-        {
-            return CompareTo(other) == 0;
-        }
-
-        public override bool Equals(object obj)
-        {
-            return Equals(obj as ConditionalRegion);
-        }
-
-        public override int GetHashCode()
-        {
-            return base.GetHashCode();
-        }
-
-        public static bool operator ==(ConditionalRegion x, ConditionalRegion y)
-        {
-            if (object.Equals(x, y))
-            {
-                return true;
-            }
-
-            return x.Equals(y);
-        }
-
-        public static bool operator !=(ConditionalRegion x, ConditionalRegion y)
-        {
-            if (object.Equals(x, y))
-            {
-                return false;
-            }
-
-            return !x.Equals(y);
-        }
-
         public override string ToString()
         {
             string stateString =

src/Microsoft.DotNet.DeadRegionAnalysis/ConditionalRegionChain.cs

@@ -7,7 +7,7 @@
 
 namespace Microsoft.DotNet.DeadRegionAnalysis
 {
-    public struct ConditionalRegionChain : IComparable<ConditionalRegionChain>, IEquatable<ConditionalRegionChain>
+    public struct ConditionalRegionChain : IComparable<ConditionalRegionChain>
     {
         private ImmutableArray<ConditionalRegion> _regions;
 
@@ -48,10 +48,5 @@ public int CompareTo(ConditionalRegionChain other)
 
             return result;
         }
-
-        public bool Equals(ConditionalRegionChain other)
-        {
-            return CompareTo(other) == 0;
-        }
     }
 }

src/Microsoft.DotNet.DeadRegionAnalysis/Microsoft.DotNet.DeadRegionAnalysis.csproj

@@ -87,6 +87,7 @@
     <Compile Include="ConditionalRegionChain.cs" />
     <Compile Include="DirectiveTriviaSyntaxExtensions.cs" />
     <Compile Include="DocumentConditionalRegionInfo.cs" />
+    <Compile Include="IAnalysisLogger.cs" />
     <Compile Include="PreprocessorExpressionSimplifier.cs" />
     <Compile Include="PreprocessorExpressionEvaluator.cs" />
     <Compile Include="PreprocessorSymbolTracker.cs" />