Use Array.Empty<T> instead of allocating an empty array

OpenXmlFormats/Wordprocessing/Document.cs

@@ -854,8 +854,8 @@ public class CT_DocPartPr
 
         public CT_DocPartPr()
         {
-            this.itemsElementNameField = new ItemsChoiceType11[0];
-            this.itemsField = new object[0];
+            this.itemsElementNameField = Array.Empty<ItemsChoiceType11>();
+            this.itemsField = Array.Empty<object>();
         }
 
         [XmlElement("behaviors", typeof(CT_DocPartBehaviors), Order = 0)]

OpenXmlFormats/Wordprocessing/Frame.cs

@@ -23,7 +23,7 @@ public class CT_Frameset
 
         public CT_Frameset()
         {
-            this.itemsField = new object[0];
+            this.itemsField = Array.Empty<object>();
             this.frameLayoutField = new CT_FrameLayout();
             this.framesetSplitbarField = new CT_FramesetSplitbar();
             this.szField = new CT_String();

OpenXmlFormats/Wordprocessing/wml.cs

@@ -129,8 +129,8 @@ public class CT_TxbxContent
 
         public CT_TxbxContent()
         {
-            this.itemsElementNameField = new ItemsChoiceType[0];
-            this.itemsField = new object[0];
+            this.itemsElementNameField = Array.Empty<ItemsChoiceType>();
+            this.itemsField = Array.Empty<object>();
         }
 
         [XmlElement("oMath", typeof(CT_OMath), Namespace = "http://schemas.openxmlformats.org/officeDocument/2006/math", Order = 0)]

main/DDF/DefaultEscherRecordFactory.cs

@@ -133,7 +133,7 @@ private static Dictionary<short, ConstructorInfo> RecordsToMap(Type[] records)
         {
             Dictionary<short, ConstructorInfo> result = new Dictionary<short, ConstructorInfo>();
             //ConstructorInfo constructor;
-            Type[] EMPTY_CLASS_ARRAY = new Type[0];
+            Type[] EMPTY_CLASS_ARRAY = Array.Empty<Type>();
             for (int i = 0; i < records.Length; i++)
             {
                 Type recordType = records[i];

main/DDF/EscherBSERecord.cs

@@ -58,7 +58,7 @@ public class EscherBSERecord : EscherRecord
         private byte field_11_unused3;
         private EscherBlipRecord field_12_blipRecord;
 
-        private byte[] _remainingData = new byte[0];
+        private byte[] _remainingData = Array.Empty<byte>();
 
         /// <summary>
         /// This method deSerializes the record from a byte array.
@@ -114,7 +114,7 @@ public override int Serialize(int offset, byte[] data, EscherSerializationListen
             listener.BeforeRecordSerialize(offset, RecordId, this);
 
             if (_remainingData == null)
-                _remainingData = new byte[0];
+                _remainingData = Array.Empty<byte>();
 
             LittleEndian.PutShort(data, offset, Options);
             LittleEndian.PutShort(data, offset + 2, RecordId);
@@ -322,7 +322,7 @@ public byte[] RemainingData
             {
                 if (value == null)
                 {
-                    _remainingData = new byte[0];
+                    _remainingData = Array.Empty<byte>();
                 }
                 else
                 {

main/DDF/EscherClientAnchorRecord.cs

@@ -52,7 +52,7 @@ public class EscherClientAnchorRecord : EscherRecord
         private short field_7_dx2;
         private short field_8_row2;
         private short field_9_dy2;
-        private byte[] remainingData = new byte[0];
+        private byte[] remainingData = Array.Empty<byte>();
         private bool shortRecord = false;
 
         /// <summary>
@@ -110,7 +110,7 @@ public override int Serialize(int offset, byte[] data, EscherSerializationListen
         {
             listener.BeforeRecordSerialize(offset, RecordId, this);
 
-            if (remainingData == null) remainingData = new byte[0];
+            if (remainingData == null) remainingData = Array.Empty<byte>();
             LittleEndian.PutShort(data, offset, Options);
             LittleEndian.PutShort(data, offset + 2, RecordId);
             int remainingBytes = remainingData.Length + (shortRecord ? 8 : 18);
@@ -329,7 +329,7 @@ public byte[] RemainingData
             {
                 if (value == null)
                 {
-                    this.remainingData = new byte[0];
+                    this.remainingData = Array.Empty<byte>();
                 }
                 else
                 {

main/DDF/EscherClientDataRecord.cs

@@ -65,7 +65,7 @@ public override int Serialize(int offset, byte[] data, EscherSerializationListen
         {
             listener.BeforeRecordSerialize(offset, RecordId, this);
 
-            if (remainingData == null) remainingData = new byte[0];
+            if (remainingData == null) remainingData = Array.Empty<byte>();
             LittleEndian.PutShort(data, offset, Options);
             LittleEndian.PutShort(data, offset + 2, RecordId);
             LittleEndian.PutInt(data, offset + 4, remainingData.Length);
@@ -137,7 +137,7 @@ public byte[] RemainingData
             get { return remainingData; }
             set
             {
-                this.remainingData = (value == null) ? new byte[0] : (byte[])value.Clone();
+                this.remainingData = (value == null) ? Array.Empty<byte>() : (byte[])value.Clone();
             }
         }
     }

main/DDF/EscherComplexProperty.cs

@@ -32,7 +32,7 @@ namespace NPOI.DDF
     /// </summary>
     public class EscherComplexProperty : EscherProperty
     {
-        private byte[] _complexData = new byte[0];
+        private byte[] _complexData = Array.Empty<byte>();
 
         /// <summary>
         /// Create a complex property using the property id and a byte array containing the complex

main/DDF/EscherTextboxRecord.cs

@@ -37,7 +37,7 @@ public class EscherTextboxRecord : EscherRecord, ICloneable
         public const short RECORD_ID = unchecked((short)0xF00D);
         public const string RECORD_DESCRIPTION = "msofbtClientTextbox";
 
-        private static readonly byte[] NO_BYTES = new byte[0];
+        private static readonly byte[] NO_BYTES = Array.Empty<byte>();
 
         /** The data for this record not including the the 8 byte header */
         private byte[] _thedata = NO_BYTES;

main/DDF/UnknownEscherRecord.cs

@@ -31,7 +31,7 @@ namespace NPOI.DDF
     /// </summary>
     public class UnknownEscherRecord : EscherRecord, ICloneable
     {
-        private static byte[] NO_BYTES = new byte[0];
+        private static byte[] NO_BYTES = Array.Empty<byte>();
 
         /** The data for this record not including the the 8 byte header */
         private byte[] _thedata = NO_BYTES;
@@ -65,7 +65,7 @@ public override int FillFields(byte[] data, int offset, IEscherRecordFactory rec
             if (IsContainerRecord)
             {
                 int bytesWritten = 0;
-                _thedata = new byte[0];
+                _thedata = Array.Empty<byte>();
                 offset += 8;
                 bytesWritten += 8;
                 while (bytesRemaining > 0)

main/HPSF/Blob.cs

@@ -12,7 +12,7 @@ public Blob(byte[] data, int offset)
 
             if (size == 0)
             {
-                _value = new byte[0];
+                _value = System.Array.Empty<byte>();
                 return;
             }
 

main/HPSF/ClipboardData.cs

@@ -22,7 +22,7 @@ public ClipboardData(byte[] data, int offset)
                 //                + "(doesn't even have format field!). "
                 //                + "Setting to format == 0 and hope for the best" );
                 _format = 0;
-                _value = new byte[0];
+                _value = System.Array.Empty<byte>();
                 return;
             }
 

main/HPSF/UnicodeString.cs

@@ -58,7 +58,7 @@ public UnicodeString(byte[] data, int offset)
 
             if (length == 0)
             {
-                _value = new byte[0];
+                _value = System.Array.Empty<byte>();
                 return;
             }
 

main/HSSF/Model/LinkTable.cs

@@ -124,8 +124,8 @@ private class ExternalBookBlock
             public ExternalBookBlock()
             {
                 _externalBookRecord = SupBookRecord.CreateAddInFunctions();
-                _externalNameRecords = new ExternalNameRecord[0];
-                _crnBlocks = new CRNBlock[0];
+                _externalNameRecords = Array.Empty<ExternalNameRecord>();
+                _crnBlocks = Array.Empty<CRNBlock>();
             }
             public ExternalBookBlock(RecordStream rs)
             {
@@ -152,7 +152,7 @@ public ExternalBookBlock(RecordStream rs)
             public ExternalBookBlock(String url, String[] sheetNames)
             {
                 _externalBookRecord = SupBookRecord.CreateExternalReferences(url, sheetNames);
-                _crnBlocks = new CRNBlock[0];
+                _crnBlocks = Array.Empty<CRNBlock>();
             }
 
             /**
@@ -163,8 +163,8 @@ public ExternalBookBlock(String url, String[] sheetNames)
             public ExternalBookBlock(int numberOfSheets)
             {
                 _externalBookRecord = SupBookRecord.CreateInternalReferences((short)numberOfSheets);
-                _externalNameRecords = new ExternalNameRecord[0];
-                _crnBlocks = new CRNBlock[0];
+                _externalNameRecords = Array.Empty<ExternalNameRecord>();
+                _crnBlocks = Array.Empty<CRNBlock>();
             }
 
             public int NumberOfNames

main/HSSF/Record/Aggregates/SharedValueManager.cs

@@ -118,7 +118,7 @@ public bool IsFirstCell(int row, int column)
         }
 
         public static readonly SharedValueManager EMPTY = new SharedValueManager(
-                new SharedFormulaRecord[0], new CellReference[0], new List<ArrayRecord>(), new List<TableRecord>());
+                Array.Empty<SharedFormulaRecord>(), Array.Empty<CellReference>(), new List<ArrayRecord>(), new List<TableRecord>());
         private List<ArrayRecord> _arrayRecords;
         private List<TableRecord> _tableRecords;
         private Dictionary<SharedFormulaRecord, SharedFormulaGroup> _groupsBySharedFormulaRecord;
@@ -149,7 +149,7 @@ public static SharedValueManager CreateEmpty()
         {
             // Note - must create distinct instances because they are assumed to be mutable.
             return new SharedValueManager(
-                new SharedFormulaRecord[0], new CellReference[0], new List<ArrayRecord>(), new List<TableRecord>());
+                Array.Empty<SharedFormulaRecord>(), Array.Empty<CellReference>(), new List<ArrayRecord>(), new List<TableRecord>());
         }
         /**
          * @param firstCells

main/HSSF/Record/CFRule12Record.cs

@@ -193,7 +193,7 @@ public CFRule12Record(RecordInputStream in1) {
             int field_4_formula2_len = in1.ReadUShort();
 
             ext_formatting_length = in1.ReadInt();
-            ext_formatting_data = new byte[0];
+            ext_formatting_data = Array.Empty<byte>();
             if (ext_formatting_length == 0) {
                 // 2 bytes reserved
                 in1.ReadUShort();

main/HSSF/Record/Chart/ChartEndBlockRecord.cs

@@ -50,7 +50,7 @@ public ChartEndBlockRecord(RecordInputStream in1)
             iObjectKind = in1.ReadShort();
             		// Often, but not always has 6 unused bytes at the end
 		    if(in1.Available() == 0) {
-			    unused = new byte[0];
+			    unused = Array.Empty<byte>();
 		    } else {
 			    unused = new byte[6];
 			    in1.ReadFully(unused);

main/HSSF/Record/Chart/EndBlockRecord.cs

@@ -55,7 +55,7 @@ public EndBlockRecord(RecordInputStream in1)
             ObjectKind = (ObjectKind) in1.ReadShort();
             // Often, but not always has 6 unused bytes at the end
 		    if(in1.Available() == 0) {
-			    unused = new byte[0];
+			    unused = Array.Empty<byte>();
 		    } else {
 			    unused = new byte[6];
 			    in1.ReadFully(unused);

main/HSSF/Record/Common/FeatProtection.cs

@@ -50,7 +50,7 @@ public class FeatProtection : SharedFeature
 
         public FeatProtection()
         {
-            securityDescriptor = new byte[0];
+            securityDescriptor = Array.Empty<byte>();
         }
 
         public FeatProtection(RecordInputStream in1)

main/HSSF/Record/Common/FeatSmartTag.cs

@@ -39,7 +39,7 @@ public class FeatSmartTag : SharedFeature
 
         public FeatSmartTag()
         {
-            data = new byte[0];
+            data = Array.Empty<byte>();
         }
 
         public FeatSmartTag(RecordInputStream in1)

main/HSSF/Record/Common/UnicodeString.cs

@@ -138,8 +138,8 @@ private void populateEmpty()
             {
                 reserved = 1;
                 phoneticText = "";
-                phRuns = new PhRun[0];
-                extraData = new byte[0];
+                phRuns = Array.Empty<PhRun>();
+                extraData = Array.Empty<byte>();
             }
             public override int GetHashCode()
             {

main/HSSF/Record/DBCellRecord.cs

@@ -38,7 +38,7 @@ public class DBCellRecord : StandardRecord, ICloneable
 
         public DBCellRecord()
         {
-            field_2_cell_offsets = new short[0];
+            field_2_cell_offsets = Array.Empty<short>();
         }
 
         /**

main/HSSF/Record/Drawing/OfficeArtFOPT.cs

@@ -10,7 +10,7 @@ public class OfficeArtFOPT
         private OfficeArtRecordHeader _rh;
         private List<OfficeArtFOPTE> _fopt;
         private Dictionary<int, OfficeArtFOPTE> dictOptions = new Dictionary<int, OfficeArtFOPTE>();
-        //private byte[] complexData = new byte[0];
+        //private byte[] complexData = Array.Empty<byte>();
 
         public OfficeArtFOPT(RecordInputStream ris)
         {

main/HSSF/Record/Drawing/OfficeArtFOPTE.cs

@@ -10,7 +10,7 @@ public class OfficeArtFOPTE
     {
         //private OfficeArtFOPTEOPID field_1_opid;
         //private int field_2_op;
-        private byte[] complexData = new byte[0];
+        private byte[] complexData = Array.Empty<byte>();
 
         public OfficeArtFOPTE(RecordInputStream ris)
         {

main/HSSF/Record/ExtSSTRecord.cs

@@ -53,7 +53,7 @@ public class ExtSSTRecord : ContinuableRecord
 
         public ExtSSTRecord()
         {
-            _sstInfos = new InfoSubRecord[0];
+            _sstInfos = Array.Empty<InfoSubRecord>();
         }
 
         /**

main/HSSF/Record/RecordInputStream.cs

@@ -526,7 +526,7 @@ public byte[] ReadRemainder()
             int size = Remaining;
             if (size == 0)
             {
-                return new byte[0];
+                return Array.Empty<byte>();
             }
             byte[] result = new byte[size];
             ReadFully(result);

main/HSSF/UserModel/HSSFPolygon.cs

@@ -191,7 +191,7 @@ public void SetPoints(int[] xPoints, int[] yPoints)
             {
                 logger.Log(POILogger.ERROR, "HSSFPolygon must have at least one point");
             }
-            EscherArrayProperty verticesProp = new EscherArrayProperty(EscherProperties.GEOMETRY__VERTICES, false, new byte[0]);
+            EscherArrayProperty verticesProp = new EscherArrayProperty(EscherProperties.GEOMETRY__VERTICES, false, System.Array.Empty<byte>());
             verticesProp.NumberOfElementsInArray = (xPoints.Length + 1);
             verticesProp.NumberOfElementsInMemory = (xPoints.Length + 1);
             verticesProp.SizeOfElements = unchecked((short)(0xFFF0));

main/POIFS/Crypt/Standard/StandardDecryptor.cs

@@ -317,17 +317,17 @@ public string AlgorithmName
 
         public byte[] DoFinal()
         {
-            return new byte[0];
+            return Array.Empty<byte>();
         }
 
         public byte[] DoFinal(byte[] input)
         {
-            return new byte[0];
+            return Array.Empty<byte>();
         }
 
         public byte[] DoFinal(byte[] input, int inOff, int length)
         {
-            return new byte[0];
+            return Array.Empty<byte>();
         }
 
         public int DoFinal(byte[] output, int outOff)
@@ -367,7 +367,7 @@ public void Init(bool forEncryption, ICipherParameters parameters)
 
         public byte[] ProcessByte(byte input)
         {
-            return new byte[0];
+            return Array.Empty<byte>();
         }
 
         public int ProcessByte(byte input, byte[] output, int outOff)
@@ -377,12 +377,12 @@ public int ProcessByte(byte input, byte[] output, int outOff)
 
         public byte[] ProcessBytes(byte[] input)
         {
-            return new byte[0];
+            return Array.Empty<byte>();
         }
 
         public byte[] ProcessBytes(byte[] input, int inOff, int length)
         {
-            return new byte[0];
+            return Array.Empty<byte>();
         }
 
         public int ProcessBytes(byte[] input, byte[] output, int outOff)

main/POIFS/FileSystem/DirectoryNode.cs

@@ -554,7 +554,7 @@ public Object[] ViewableArray
         {
             get
             {
-                return new Object[0];
+                return Array.Empty<Object>();
             }
         }
 

main/POIFS/FileSystem/DocumentNode.cs

@@ -105,7 +105,7 @@ protected override bool IsDeleteOK
 
         public Object[] ViewableArray
         {
-            get { return new Object[0]; }
+            get { return Array.Empty<Object>(); }
         }
 
         /**