SWEEP: Use pattern matching, #667 (#1082)

* SWEEP: Replace type-check-and-cast with pattern matching, #667

* SWEEP: Use negated pattern matching, #667

src/Lucene.Net.Analysis.Common/Analysis/CharFilter/HTMLStripCharFilter.cs

@@ -30868,7 +30868,7 @@ public HTMLStripCharFilter(TextReader source, ICollection<string> escapedTags)
         /// <returns></returns>
         private static BufferedCharFilter GetBufferedReader(TextReader reader)
         {
-            return (reader is BufferedCharFilter) ? (BufferedCharFilter)reader : new BufferedCharFilter(reader);
+            return reader as BufferedCharFilter ?? new BufferedCharFilter(reader);
         }
 
         public override int Read()

src/Lucene.Net.Analysis.Common/Analysis/CharFilter/MappingCharFilter.cs

@@ -55,7 +55,7 @@ public class MappingCharFilter : BaseCharFilter
 
         /// <summary>
         /// Default constructor that takes a <see cref="TextReader"/>. </summary>
-        public MappingCharFilter(NormalizeCharMap normMap, TextReader @in) 
+        public MappingCharFilter(NormalizeCharMap normMap, TextReader @in)
             : base(@in)
         {
             //LUCENENET support to reset the reader.
@@ -79,20 +79,20 @@ public MappingCharFilter(NormalizeCharMap normMap, TextReader @in)
 
         /// <summary>
         /// LUCENENET: Copied this method from the <see cref="WordlistLoader"/> class - this class requires readers
-        /// with a Reset() method (which .NET readers don't support). So, we use the <see cref="BufferedCharFilter"/> 
-        /// (which is similar to Java BufferedReader) as a wrapper for whatever reader the user passes 
+        /// with a Reset() method (which .NET readers don't support). So, we use the <see cref="BufferedCharFilter"/>
+        /// (which is similar to Java BufferedReader) as a wrapper for whatever reader the user passes
         /// (unless it is already a <see cref="BufferedCharFilter"/>).
         /// </summary>
         /// <param name="reader"></param>
         /// <returns></returns>
         private static BufferedCharFilter GetBufferedReader(TextReader reader)
         {
-            return (reader is BufferedCharFilter) ? (BufferedCharFilter)reader : new BufferedCharFilter(reader);
+            return reader as BufferedCharFilter ?? new BufferedCharFilter(reader);
         }
 
         public override void Reset()
         {
-            // LUCENENET: reset the BufferedCharFilter. 
+            // LUCENENET: reset the BufferedCharFilter.
             _input.Reset();
             buffer.Reset(_input);
             replacement = null;
@@ -240,4 +240,4 @@ public override int Read(char[] cbuf, int off, int len)
             return numRead == 0 ? -1 : numRead;
         }
     }
-}
+}

src/Lucene.Net.Analysis.Common/Analysis/Compound/Hyphenation/HyphenationTree.cs

@@ -477,9 +477,9 @@ public virtual Hyphenation Hyphenate(char[] w, int offset, int len, int remainCh
                     object o = hw[i];
                     // j = index(sw) = letterindex(word)?
                     // result[k] = corresponding index(w)
-                    if (o is string)
+                    if (o is string os)
                     {
-                        j += ((string)o).Length;
+                        j += os.Length;
                         if (j >= remainCharCount && j < (len - pushCharCount))
                         {
                             result[k++] = j + iIgnoreAtBeginning;

src/Lucene.Net.Analysis.Common/Analysis/Compound/Hyphenation/PatternParser.cs

@@ -17,9 +17,9 @@ namespace Lucene.Net.Analysis.Compound.Hyphenation
      * The ASF licenses this file to You under the Apache License, Version 2.0
      * (the "License"); you may not use this file except in compliance with
      * the License.  You may obtain a copy of the License at
-     * 
+     *
      *      http://www.apache.org/licenses/LICENSE-2.0
-     * 
+     *
      * Unless required by applicable law or agreed to in writing, software
      * distributed under the License is distributed on an "AS IS" BASIS,
      * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -62,7 +62,7 @@ public PatternParser()
             hyphenChar = '-'; // default
         }
 
-        public PatternParser(IPatternConsumer consumer) 
+        public PatternParser(IPatternConsumer consumer)
             : this()
         {
             this.consumer = consumer;
@@ -127,8 +127,8 @@ public virtual void Parse(FileInfo file, Encoding encoding)
         /// <param name="xmlStream">
         /// The stream containing the XML data.
         /// <para/>
-        /// The <see cref="PatternParser"/> scans the first bytes of the stream looking for a byte order mark 
-        /// or other sign of encoding. When encoding is determined, the encoding is used to continue reading 
+        /// The <see cref="PatternParser"/> scans the first bytes of the stream looking for a byte order mark
+        /// or other sign of encoding. When encoding is determined, the encoding is used to continue reading
         /// the stream, and processing continues parsing the input as a stream of (Unicode) characters.
         /// </param>
         /// <exception cref="IOException"> In case of an exception while parsing </exception>
@@ -294,9 +294,8 @@ protected virtual IList<object> NormalizeException<T1>(IList<T1> ex)
             for (int i = 0; i < ex.Count; i++)
             {
                 object item = ex[i];
-                if (item is string)
+                if (item is string str)
                 {
-                    string str = (string)item;
                     StringBuilder buf = new StringBuilder();
                     for (int j = 0; j < str.Length; j++)
                     {
@@ -335,9 +334,9 @@ protected virtual string GetExceptionWord<T1>(IList<T1> ex)
             for (int i = 0; i < ex.Count; i++)
             {
                 object item = ex[i];
-                if (item is string)
+                if (item is string str)
                 {
-                    res.Append((string)item);
+                    res.Append(str);
                 }
                 else
                 {
@@ -396,9 +395,9 @@ public override object GetEntity(Uri absoluteUri, string role, Type ofObjectToRe
         /// <summary>
         /// Receive notification of the beginning of an element.
         /// <para/>
-        /// The Parser will invoke this method at the beginning of every element in the XML document; 
-        /// there will be a corresponding <see cref="EndElement"/> event for every <see cref="StartElement"/> event 
-        /// (even when the element is empty). All of the element's content will be reported, 
+        /// The Parser will invoke this method at the beginning of every element in the XML document;
+        /// there will be a corresponding <see cref="EndElement"/> event for every <see cref="StartElement"/> event
+        /// (even when the element is empty). All of the element's content will be reported,
         /// in order, before the corresponding endElement event.
         /// </summary>
         /// <param name="uri">the Namespace URI, or the empty string if the element has no Namespace URI or if Namespace processing is not being performed</param>
@@ -442,8 +441,8 @@ public virtual void StartElement(string uri, string local, string raw, IDictiona
         /// <summary>
         /// Receive notification of the end of an element.
         /// <para/>
-        /// The parser will invoke this method at the end of every element in the XML document; 
-        /// there will be a corresponding <see cref="StartElement"/> event for every 
+        /// The parser will invoke this method at the end of every element in the XML document;
+        /// there will be a corresponding <see cref="StartElement"/> event for every
         /// <see cref="EndElement"/> event (even when the element is empty).
         /// </summary>
         /// <param name="uri">the Namespace URI, or the empty string if the element has no Namespace URI or if Namespace processing is not being performed</param>
@@ -489,9 +488,9 @@ public virtual void EndElement(string uri, string local, string raw)
         /// <summary>
         /// Receive notification of character data.
         /// <para/>
-        /// The Parser will call this method to report each chunk of character data. Parsers may 
-        /// return all contiguous character data in a single chunk, or they may split it into 
-        /// several chunks; however, all of the characters in any single event must come from 
+        /// The Parser will call this method to report each chunk of character data. Parsers may
+        /// return all contiguous character data in a single chunk, or they may split it into
+        /// several chunks; however, all of the characters in any single event must come from
         /// the same external entity so that the Locator provides useful information.
         /// <para/>
         /// The application must not attempt to read from the array outside of the specified range.
@@ -526,4 +525,4 @@ public virtual void Characters(char[] ch, int start, int length)
             }
         }
     }
-}
+}

src/Lucene.Net.Analysis.Common/Analysis/Util/CharArrayMap.cs

@@ -2713,7 +2713,7 @@ void ICollection.CopyTo(Array array, int index)
             }
             else
             {
-                if (!(array is object[] objects))
+                if (array is not object[] objects)
                 {
                     throw new ArgumentException(SR.Argument_InvalidArrayType);
                 }

src/Lucene.Net.Analysis.Common/Analysis/Util/FilesystemResourceLoader.cs

@@ -72,7 +72,7 @@ public FilesystemResourceLoader(DirectoryInfo baseDirectory, IResourceLoader @de
         {
             // LUCENENET NOTE: If you call DirectoryInfo.Create() it doesn't set the DirectoryInfo.Exists
             // flag to true, so we use the Directory object to check the path explicitly.
-            if (!(baseDirectory is null) && !Directory.Exists(baseDirectory.FullName))
+            if (baseDirectory is not null && !Directory.Exists(baseDirectory.FullName))
             {
                 throw new ArgumentException("baseDirectory is not a directory or is null");
             }

src/Lucene.Net.Analysis.Phonetic/Language/DaitchMokotoffSoundex.cs

@@ -100,12 +100,12 @@ public override bool Equals(object other)
                 {
                     return true;
                 }
-                if (!(other is Branch))
+                if (other is not Branch branch)
                 {
                     return false;
                 }
 
-                return ToString().Equals(((Branch)other).ToString(), StringComparison.Ordinal);
+                return ToString().Equals(branch.ToString(), StringComparison.Ordinal);
             }
 
             /// <summary>

src/Lucene.Net.Benchmark/Support/TagSoup/Parser.cs

@@ -525,7 +525,7 @@ private TextReader GetReader(InputSource s)
                 {
                     i = GetInputStream(publicId, systemId);
                 }
-                if (!(i is BufferedStream))
+                if (i is not BufferedStream)
                 {
                     i = new BufferedStream(i);
                 }

src/Lucene.Net.Codecs/Bloom/BloomFilteringPostingsFormat.cs

@@ -233,7 +233,7 @@ public override TermsEnum GetEnumerator()
 
                 public override TermsEnum GetEnumerator(TermsEnum reuse)
                 {
-                    if (!(reuse is null) && reuse is BloomFilteredTermsEnum bfte && bfte.filter == _filter)
+                    if (reuse is not null && reuse is BloomFilteredTermsEnum bfte && bfte.filter == _filter)
                     {
                         // recycle the existing BloomFilteredTermsEnum by asking the delegate
                         // to recycle its contained TermsEnum

src/Lucene.Net.Codecs/Memory/DirectPostingsFormat.cs

@@ -799,7 +799,7 @@ public override TermsEnum GetEnumerator()
 
             public override TermsEnum GetEnumerator(TermsEnum reuse)
             {
-                if (!(reuse is DirectTermsEnum termsEnum) || !termsEnum.CanReuse(terms))
+                if (reuse is not DirectTermsEnum termsEnum || !termsEnum.CanReuse(terms))
                     termsEnum = new DirectTermsEnum(this);
 
                 termsEnum.Reset();

src/Lucene.Net.Codecs/Memory/FSTTermOutputs.cs

@@ -103,10 +103,9 @@ public override bool Equals(object other)
                 if (other == this)
                     return true;
 
-                if (!(other is TermData))
+                if (other is not TermData _other)
                     return false;
 
-                var _other = (TermData) other;
                 return StatsEqual(this, _other) && Int64sEqual(this, _other) && BytesEqual(this, _other);
             }
         }

src/Lucene.Net.Codecs/Memory/MemoryPostingsFormat.cs

@@ -808,7 +808,7 @@ public override DocsEnum Docs(IBits liveDocs, DocsEnum reuse, DocsFlags flags)
             {
                 DecodeMetaData();
 
-                if (reuse is null || !(reuse is FSTDocsEnum docsEnum) || !docsEnum.CanReuse(field.IndexOptions, field.HasPayloads))
+                if (reuse is null || reuse is not FSTDocsEnum docsEnum || !docsEnum.CanReuse(field.IndexOptions, field.HasPayloads))
                     docsEnum = new FSTDocsEnum(field.IndexOptions, field.HasPayloads);
 
                 return docsEnum.Reset(this.postingsSpare, liveDocs, docFreq);
@@ -823,7 +823,7 @@ public override DocsAndPositionsEnum DocsAndPositions(IBits liveDocs, DocsAndPos
                     return null;
                 }
                 DecodeMetaData();
-                if (reuse is null || !(reuse is FSTDocsAndPositionsEnum docsAndPositionsEnum) || !docsAndPositionsEnum.CanReuse(field.HasPayloads, hasOffsets))
+                if (reuse is null || reuse is not FSTDocsAndPositionsEnum docsAndPositionsEnum || !docsAndPositionsEnum.CanReuse(field.HasPayloads, hasOffsets))
                     docsAndPositionsEnum = new FSTDocsAndPositionsEnum(field.HasPayloads, hasOffsets);
 
                 //System.out.println("D&P reset this=" + this);

src/Lucene.Net.Codecs/Pulsing/PulsingPostingsReader.cs

@@ -253,7 +253,7 @@ public override DocsEnum Docs(FieldInfo field, BlockTermState termState, IBits l
                 return postings.Reset(liveDocs, termState2);
             }
 
-            if (!(reuse is PulsingDocsEnum))
+            if (reuse is not PulsingDocsEnum)
                 return _wrappedPostingsReader.Docs(field, termState2.WrappedTermState, liveDocs, reuse, flags);
 
             var wrapped = _wrappedPostingsReader.Docs(field, termState2.WrappedTermState, liveDocs,
@@ -299,7 +299,7 @@ public override DocsAndPositionsEnum DocsAndPositions(FieldInfo field, BlockTerm
                 return postings.Reset(liveDocs, termState2);
             }
 
-            if (!(reuse is PulsingDocsAndPositionsEnum))
+            if (reuse is not PulsingDocsAndPositionsEnum)
                 return _wrappedPostingsReader.DocsAndPositions(field, termState2.WrappedTermState, liveDocs, reuse,
                     flags);
 

src/Lucene.Net.Codecs/Sep/SepPostingsReader.cs

@@ -245,7 +245,7 @@ public override DocsEnum Docs(FieldInfo fieldInfo, BlockTermState termState, IBi
             // If you are using ParellelReader, and pass in a
             // reused DocsAndPositionsEnum, it could have come
             // from another reader also using sep codec
-            if (reuse is null || !(reuse is SepDocsEnum docsEnum) || docsEnum.startDocIn != docIn)
+            if (reuse is null || reuse is not SepDocsEnum docsEnum || docsEnum.startDocIn != docIn)
                 docsEnum = new SepDocsEnum(this);
 
             return docsEnum.Init(fieldInfo, termState_, liveDocs);
@@ -260,7 +260,7 @@ public override DocsAndPositionsEnum DocsAndPositions(FieldInfo fieldInfo, Block
             // If you are using ParellelReader, and pass in a
             // reused DocsAndPositionsEnum, it could have come
             // from another reader also using sep codec
-            if (reuse is null || !(reuse is SepDocsAndPositionsEnum postingsEnum) || postingsEnum.startDocIn != docIn)
+            if (reuse is null || reuse is not SepDocsAndPositionsEnum postingsEnum || postingsEnum.startDocIn != docIn)
                 postingsEnum = new SepDocsAndPositionsEnum(this);
 
             return postingsEnum.Init(fieldInfo, termState_, liveDocs);

src/Lucene.Net.Codecs/SimpleText/SimpleTextFieldsReader.cs

@@ -208,7 +208,7 @@ public override BytesRef Next()
 
             public override DocsEnum Docs(IBits liveDocs, DocsEnum reuse, DocsFlags flags)
             {
-                if (reuse is null || !(reuse is SimpleTextDocsEnum docsEnum) || !docsEnum.CanReuse(outerInstance.input))
+                if (reuse is null || reuse is not SimpleTextDocsEnum docsEnum || !docsEnum.CanReuse(outerInstance.input))
                     docsEnum = new SimpleTextDocsEnum(outerInstance);
 
                 return docsEnum.Reset(docsStart, liveDocs, indexOptions == IndexOptions.DOCS_ONLY, docFreq);
@@ -223,7 +223,7 @@ public override DocsAndPositionsEnum DocsAndPositions(IBits liveDocs, DocsAndPos
                     return null;
                 }
 
-                if (reuse is null || !(reuse is SimpleTextDocsAndPositionsEnum docsAndPositionsEnum) || !docsAndPositionsEnum.CanReuse(outerInstance.input))
+                if (reuse is null || reuse is not SimpleTextDocsAndPositionsEnum docsAndPositionsEnum || !docsAndPositionsEnum.CanReuse(outerInstance.input))
                     docsAndPositionsEnum = new SimpleTextDocsAndPositionsEnum(outerInstance);
 
                 return docsAndPositionsEnum.Reset(docsStart, liveDocs, indexOptions, docFreq);

src/Lucene.Net.Facet/DrillDownQuery.cs

@@ -291,12 +291,11 @@ public override int GetHashCode()
 
         public override bool Equals(object obj)
         {
-            if (!(obj is DrillDownQuery))
+            if (obj is not DrillDownQuery other)
             {
                 return false;
             }
 
-            DrillDownQuery other = (DrillDownQuery)obj;
             return query.Equals(other.query) && base.Equals(other);
         }
 

src/Lucene.Net.Facet/FacetsCollector.cs

@@ -325,7 +325,7 @@ private static TopDocs DoSearch(IndexSearcher searcher, ScoreDoc after, Query q,
 
             if (sort != null)
             {
-                if (after != null && !(after is FieldDoc))
+                if (after != null && after is not FieldDoc)
                 {
                     // TODO: if we fix type safety of TopFieldDocs we can
                     // remove this

src/Lucene.Net.Facet/Taxonomy/CategoryPath.cs

@@ -217,12 +217,11 @@ public virtual int CopyFullPath(char[] buf, int start, char delimiter)
 
         public override bool Equals(object obj)
         {
-            if (!(obj is CategoryPath))
+            if (obj is not CategoryPath other)
             {
                 return false;
             }
 
-            CategoryPath other = (CategoryPath)obj;
             if (Length != other.Length)
             {
                 return false; // not same length, cannot be equal
@@ -350,7 +349,7 @@ public virtual string ToString(char delimiter)
 
         public static bool operator <(CategoryPath left, CategoryPath right)
         {
-            return left is null ? !(right is null) : left.CompareTo(right) < 0;
+            return left is null ? right is not null : left.CompareTo(right) < 0;
         }
 
         public static bool operator <=(CategoryPath left, CategoryPath right)
@@ -360,7 +359,7 @@ public virtual string ToString(char delimiter)
 
         public static bool operator >(CategoryPath left, CategoryPath right)
         {
-            return !(left is null) && left.CompareTo(right) > 0;
+            return left is not null && left.CompareTo(right) > 0;
         }
 
         public static bool operator >=(CategoryPath left, CategoryPath right)

src/Lucene.Net.Facet/Taxonomy/Directory/DirectoryTaxonomyWriter.cs

@@ -237,7 +237,7 @@ public DirectoryTaxonomyWriter(DirectoryTaxonomyIndexWriterFactory indexWriterFa
             // verify (to some extent) that merge policy in effect would preserve category docids
             if (indexWriter != null)
             {
-                if (Debugging.AssertsEnabled) Debugging.Assert(!(indexWriter.Config.MergePolicy is TieredMergePolicy), "for preserving category docids, merging none-adjacent segments is not allowed");
+                if (Debugging.AssertsEnabled) Debugging.Assert(indexWriter.Config.MergePolicy is not TieredMergePolicy, "for preserving category docids, merging none-adjacent segments is not allowed");
             }
 
             // after we opened the writer, and the index is locked, it's safe to check