PR feedback, make extensions generic

src/Lucene.Net.Analysis.Common/Analysis/NGram/NGramTokenFilter.cs

@@ -121,13 +121,6 @@ public int PositionIncrement
                 get => 0;
                 set => _ = value;
             }
-
-            // LUCENENET specific - The interface requires this to be implemented, since we added it to avoid casts.
-            public void CopyTo(IAttribute target) => _ = target;
-
-            public void Clear()
-            {
-            }
         }
 
         private sealed class PositionLengthAttributeAnonymousClass : IPositionLengthAttribute
@@ -137,13 +130,6 @@ public int PositionLength
                 get => 0;
                 set => _ = value;
             }
-
-            // LUCENENET specific - The interface requires this to be implemented, since we added it to avoid casts.
-            public void CopyTo(IAttribute target) => _ = target;
-
-            public void Clear()
-            {
-            }
         }
 
         /// <summary>

src/Lucene.Net/Analysis/Token.cs

@@ -65,7 +65,7 @@ namespace Lucene.Net.Analysis
     /// Failing that, to create a new <see cref="Token"/> you should first use
     /// one of the constructors that starts with null text.  To load
     /// the token from a char[] use <see cref="ICharTermAttribute.CopyBuffer(char[], int, int)"/>.
-    /// To load from a <see cref="string"/> use <see cref="ICharTermAttribute.Clear()"/> (or <see cref="CharTermAttributeExtensions.SetEmpty(ICharTermAttribute)"/>) followed by
+    /// To load from a <see cref="string"/> use <see cref="ICharTermAttribute.Clear()"/> (or <see cref="CharTermAttributeExtensions.SetEmpty{T}(T)"/>) followed by
     /// <see cref="ICharTermAttribute.Append(string)"/> or <see cref="ICharTermAttribute.Append(string, int, int)"/>.
     /// Alternatively you can get the <see cref="Token"/>'s termBuffer by calling either <see cref="ICharTermAttribute.Buffer"/>,
     /// if you know that your text is shorter than the capacity of the termBuffer

src/Lucene.Net/Analysis/TokenAttributes/CharTermAttribute.cs

@@ -73,13 +73,22 @@ public interface ICharTermAttribute : IAttribute, ICharSequence, IAppendable
         /// LUCENENET: To mimic StringBuilder, we allow this to be settable.
         /// This replaces the chainable SetLength method in the Java version.
         /// </remarks>
-        /// <seealso cref="CharTermAttributeExtensions.SetLength(ICharTermAttribute, int)"/>
+        /// <seealso cref="CharTermAttributeExtensions.SetLength{T}(T, int)"/>
         new int Length { get; set; }
 
         // LUCENENET specific: Redefining this[] to make it settable
         new char this[int index] { get; set; }
 
-        // the following methods are redefined to get rid of IOException declaration:
+        /// <summary>
+        /// Clears the values in this attribute and resets it to its
+        /// default value.
+        /// </summary>
+        /// <remarks>
+        /// LUCENENET specific - This method is not part of the Java Lucene API.
+        /// This was added to be a more consistent way to clear attributes than SetEmpty().
+        /// </remarks>
+        /// <seealso cref="CharTermAttributeExtensions.SetEmpty{T}(T)"/>
+        void Clear();
 
         /// <summary>
         /// Appends the contents of the <see cref="ICharSequence"/> to this character sequence.
@@ -272,16 +281,5 @@ public interface ICharTermAttribute : IAttribute, ICharSequence, IAppendable
         /// </summary>
         /// <param name="value">The sequence of characters to append.</param>
         ICharTermAttribute Append(ICharTermAttribute value);
-
-        /// <summary>
-        /// Clears the values in this attribute and resets it to its
-        /// default value.
-        /// </summary>
-        /// <remarks>
-        /// LUCENENET specific - This method is not part of the Java Lucene API.
-        /// This was added to be a more consistent way to clear attributes than SetEmpty().
-        /// </remarks>
-        /// <seealso cref="CharTermAttributeExtensions.SetEmpty(ICharTermAttribute)"/>
-        void Clear();
     }
 }

src/Lucene.Net/Analysis/TokenAttributes/CharTermAttributeImpl.cs

@@ -70,8 +70,6 @@ public void CopyBuffer(char[] buffer, int offset, int length)
             termLength = length;
         }
 
-        char[] ICharTermAttribute.Buffer => termBuffer;
-
         [WritableArray]
         [SuppressMessage("Microsoft.Performance", "CA1819", Justification = "Lucene's design requires some writable array properties")]
         public char[] Buffer => termBuffer;
@@ -107,14 +105,6 @@ private void GrowTermBuffer(int newSize)
             }
         }
 
-        int ICharTermAttribute.Length
-        {
-            get => Length;
-            set => Length = value;
-        }
-
-        int ICharSequence.Length => Length;
-
         public int Length
         {
             get => termLength;
@@ -124,7 +114,7 @@ public int Length
                 if (value < 0)
                     throw new ArgumentOutOfRangeException(nameof(value), value, $"{nameof(value)} must not be negative.");
                 if (value > termBuffer.Length)
-                    throw new ArgumentOutOfRangeException(nameof(value), value, "length " + value + " exceeds the size of the termBuffer (" + termBuffer.Length + ")");
+                    throw new ArgumentOutOfRangeException(nameof(value), value, $"length {value} exceeds the size of the termBuffer ({termBuffer.Length})");
 
                 termLength = value;
             }
@@ -142,12 +132,6 @@ public virtual void FillBytesRef()
 
         // *** CharSequence interface ***
 
-        // LUCENENET specific: Replaced CharAt(int) with this[int] to .NETify
-
-        char ICharSequence.this[int index] => this[index];
-
-        char ICharTermAttribute.this[int index] { get => this[index]; set => this[index] = value; }
-
         // LUCENENET specific indexer to make CharTermAttribute act more like a .NET type
         public char this[int index]
         {
@@ -480,10 +464,6 @@ public override void CopyTo(IAttribute target) // LUCENENET specific - intention
 
         #region ICharTermAttribute Members
 
-        void ICharTermAttribute.CopyBuffer(char[] buffer, int offset, int length) => CopyBuffer(buffer, offset, length);
-
-        char[] ICharTermAttribute.ResizeBuffer(int newSize) => ResizeBuffer(newSize);
-
         ICharTermAttribute ICharTermAttribute.Append(ICharSequence value) => Append(value);
 
         ICharTermAttribute ICharTermAttribute.Append(ICharSequence value, int startIndex, int count) => Append(value, startIndex, count);

src/Lucene.Net/Support/Analysis/TokenAttributes/Extensions/CharTermAttributeExtensions.cs

@@ -38,7 +38,8 @@ public static class CharTermAttributeExtensions
         /// </code>
         /// </summary>
         /// <param name="length">The truncated length</param>
-        public static ICharTermAttribute SetLength(this ICharTermAttribute termAttr, int length)
+        public static T SetLength<T>(this T termAttr, int length)
+            where T : ICharTermAttribute
         {
             if (termAttr is null)
             {
@@ -59,7 +60,8 @@ public static ICharTermAttribute SetLength(this ICharTermAttribute termAttr, int
         /// obj.SetEmpty().Append("hey you");
         /// </code>
         /// </summary>
-        public static ICharTermAttribute SetEmpty(this ICharTermAttribute termAttr)
+        public static T SetEmpty<T>(this T termAttr)
+            where T : ICharTermAttribute
         {
             if (termAttr is null)
             {