Fix review comments

Author: Shwetap05

src/Microsoft.OpenApi/Services/OpenApiComparer.cs

@@ -26,11 +26,11 @@ public static IEnumerable<OpenApiDifference> Compare(OpenApiDocument source, Ope
                 throw Error.ArgumentNull(nameof(target));
             }
 
-            var comparisionContext = new ComparisonContext(new OpenApiComparerFactory(), source, target);
+            var comparisonContext = new ComparisonContext(new OpenApiComparerFactory(), source, target);
 
-            new OpenApiDocumentComparer().Compare(source, target, comparisionContext);
+            new OpenApiDocumentComparer().Compare(source, target, comparisonContext);
 
-            return comparisionContext.OpenApiDifferences;
+            return comparisonContext.OpenApiDifferences;
         }
     }
 }

src/Microsoft.OpenApi/Services/OpenApiComparerBase.cs

@@ -104,7 +104,7 @@ internal void Compare(decimal? source, decimal? target, ComparisonContext compar
         /// <param name="source">The source.</param>
         /// <param name="target">The target.</param>
         /// <param name="comparisonContext">The context under which to compare the objects.</param>
-        internal void Compare<TE>(Enum source, Enum target, ComparisonContext comparisonContext)
+        internal void Compare<TEnum>(Enum source, Enum target, ComparisonContext comparisonContext)
         {
             if (source == null && target == null)
             {
@@ -116,7 +116,7 @@ internal void Compare<TE>(Enum source, Enum target, ComparisonContext comparison
                 comparisonContext.AddOpenApiDifference(new OpenApiDifference
                 {
                     OpenApiDifferenceOperation = OpenApiDifferenceOperation.Update,
-                    OpenApiComparedElementType = typeof(TE),
+                    OpenApiComparedElementType = typeof(TEnum),
                     SourceValue = source,
                     TargetValue = target,
                     Pointer = comparisonContext.PathString
@@ -130,7 +130,7 @@ internal void Compare<TE>(Enum source, Enum target, ComparisonContext comparison
                 comparisonContext.AddOpenApiDifference(new OpenApiDifference
                 {
                     OpenApiDifferenceOperation = OpenApiDifferenceOperation.Update,
-                    OpenApiComparedElementType = typeof(T),
+                    OpenApiComparedElementType = typeof(TEnum),
                     SourceValue = source,
                     TargetValue = target,
                     Pointer = comparisonContext.PathString
@@ -149,7 +149,7 @@ internal void WalkAndAddOpenApiDifference(
             string segment,
             OpenApiDifference openApiDifference)
         {
-            comparisonContext.Enter(segment.Replace("/", "~1"));
+            comparisonContext.Enter(segment.Replace("/", "~1").Replace("~", "~0"));
             openApiDifference.Pointer = comparisonContext.PathString;
             comparisonContext.AddOpenApiDifference(openApiDifference);
             comparisonContext.Exit();
@@ -166,7 +166,7 @@ protected virtual void WalkAndCompare(
             string segment,
             Action compare)
         {
-            comparisonContext.Enter(segment.Replace("/", "~1"));
+            comparisonContext.Enter(segment.Replace("/", "~1").Replace("~", "~0"));
             compare();
             comparisonContext.Exit();
         }

src/Microsoft.OpenApi/Services/OpenApiEncodingComparer.cs

@@ -51,7 +51,6 @@ public override void Compare(
             WalkAndCompare(comparisonContext, OpenApiConstants.AllowReserved,
                 () => Compare(sourceEncoding.AllowReserved, targetEncoding.AllowReserved, comparisonContext));
 
-
             WalkAndCompare(comparisonContext, OpenApiConstants.Style,
                 () => Compare<ParameterStyle>(sourceEncoding.Style, targetEncoding.Style, comparisonContext));
 

src/Microsoft.OpenApi/Services/OpenApiHeaderComparer.cs

@@ -48,7 +48,7 @@ public override void Compare(
             {
                 WalkAndAddOpenApiDifference(
                     comparisonContext,
-                    "$ref",
+                    OpenApiConstants.DollarRef,
                     new OpenApiDifference
                     {
                         OpenApiDifferenceOperation = OpenApiDifferenceOperation.Update,
@@ -63,7 +63,7 @@ public override void Compare(
             if (sourceHeader.Reference != null)
             {
                 sourceHeader = (OpenApiHeader) comparisonContext.SourceDocument.ResolveReference(
-                    targetHeader.Reference);
+                    sourceHeader.Reference);
             }
 
             if (targetHeader.Reference != null)

src/Microsoft.OpenApi/Services/OpenApiMediaTypeComparer.cs

@@ -48,7 +48,7 @@ public override void Compare(
 
             WalkAndCompare(
                 comparisonContext,
-                OpenApiConstants.Content,
+                OpenApiConstants.Encoding,
                 () => comparisonContext
                     .GetComparer<IDictionary<string, OpenApiEncoding>>()
                     .Compare(sourceMediaType.Encoding, sourceMediaType.Encoding, comparisonContext));

src/Microsoft.OpenApi/Services/OpenApiOperationComparer.cs

@@ -64,7 +64,7 @@ public override void Compare(
 
             WalkAndCompare(
                 comparisonContext,
-                OpenApiConstants.Components,
+                OpenApiConstants.Servers,
                 () => comparisonContext
                     .GetComparer<IList<OpenApiServer>>()
                     .Compare(sourceOperation?.Servers, targetOperation?.Servers, comparisonContext));

src/Microsoft.OpenApi/Services/OpenApiParameterComparer.cs

@@ -54,6 +54,7 @@ public override void Compare(
                     .GetComparer<IDictionary<string, OpenApiMediaType>>()
                     .Compare(sourceParameter.Content, targetParameter.Content, comparisonContext));
 
+            // To Do Add compare for reference object
             // To Do Compare Examples
             // To Do Compare parameter as IOpenApiExtensible
         }

src/Microsoft.OpenApi/Services/OpenApiParametersComparer.cs

@@ -43,7 +43,7 @@ public override void Compare(
             {
                 WalkAndAddOpenApiDifference(
                     comparisonContext,
-                    i.ToString(),
+                    targetParameters.IndexOf(newParametersInTarget[i]).ToString(),
                     new OpenApiDifference
                     {
                         OpenApiDifferenceOperation = OpenApiDifferenceOperation.Add,
@@ -60,7 +60,7 @@ public override void Compare(
             {
                 WalkAndAddOpenApiDifference(
                     comparisonContext,
-                    i.ToString(),
+                    sourceParameters.IndexOf(removedParameters[i]).ToString(),
                     new OpenApiDifference
                     {
                         OpenApiDifferenceOperation = OpenApiDifferenceOperation.Remove,

src/Microsoft.OpenApi/Services/OpenApiPathItemComparer.cs

@@ -49,7 +49,7 @@ public override void Compare(
 
             WalkAndCompare(
                 comparisonContext,
-                OpenApiConstants.Parameters,
+                OpenApiConstants.Servers,
                 () => comparisonContext
                     .GetComparer<IList<OpenApiServer>>()
                     .Compare(sourcePathItem?.Servers, targetPathItem?.Servers, comparisonContext));

src/Microsoft.OpenApi/Services/OpenApiRequestBodyComparer.cs

@@ -48,7 +48,7 @@ public override void Compare(
             {
                 WalkAndAddOpenApiDifference(
                     comparisonContext,
-                    "$ref",
+                    OpenApiConstants.DollarRef,
                     new OpenApiDifference
                     {
                         OpenApiDifferenceOperation = OpenApiDifferenceOperation.Update,