Per entry compression was being written out incorrectly on the centra…

.travis.yml

@@ -1,5 +1,8 @@
 dist: trusty
 language: csharp
+cache:
+  directories:
+  - $HOME/.dotnet
 solution: SharpCompress.sln
 matrix:
   include:

src/SharpCompress/Writers/Zip/ZipCentralDirectoryEntry.cs

@@ -9,18 +9,27 @@ namespace SharpCompress.Writers.Zip
 {
     internal class ZipCentralDirectoryEntry
     {
-        internal string FileName { get; set; }
+        private readonly ZipCompressionMethod compression;
+        private readonly string fileName;
+
+        public ZipCentralDirectoryEntry(ZipCompressionMethod compression, string fileName, ulong headerOffset)
+        {
+            this.compression = compression;
+            this.fileName = fileName;
+            HeaderOffset = headerOffset;
+        }
+
         internal DateTime? ModificationTime { get; set; }
         internal string Comment { get; set; }
         internal uint Crc { get; set; }
-        internal ulong HeaderOffset { get; set; }
         internal ulong Compressed { get; set; }
         internal ulong Decompressed { get; set; }
         internal ushort Zip64HeaderOffset { get; set; }
+        internal ulong HeaderOffset { get; }
 
-        internal uint Write(Stream outputStream, ZipCompressionMethod compression)
+        internal uint Write(Stream outputStream)
         {
-            byte[] encodedFilename = Encoding.UTF8.GetBytes(FileName);
+            byte[] encodedFilename = Encoding.UTF8.GetBytes(fileName);
             byte[] encodedComment = Encoding.UTF8.GetBytes(Comment);
 
 			var zip64_stream = Compressed >= uint.MaxValue || Decompressed >= uint.MaxValue;

src/SharpCompress/Writers/Zip/ZipWriter.cs

@@ -55,7 +55,7 @@ protected override void Dispose(bool isDisposing)
                 ulong size = 0;
                 foreach (ZipCentralDirectoryEntry entry in entries)
                 {
-                    size += entry.Write(OutputStream, ToZipCompressionMethod(compressionType));
+                    size += entry.Write(OutputStream);
                 }
                 WriteEndRecord(size);
             }
@@ -108,16 +108,16 @@ public void Write(string entryPath, Stream source, ZipWriterEntryOptions zipWrit
 
         public Stream WriteToStream(string entryPath, ZipWriterEntryOptions options)
         {
+            var compression = ToZipCompressionMethod(options.CompressionType ?? compressionType);
+
             entryPath = NormalizeFilename(entryPath);
             options.ModificationDateTime = options.ModificationDateTime ?? DateTime.Now;
             options.EntryComment = options.EntryComment ?? string.Empty;
-            var entry = new ZipCentralDirectoryEntry
+            var entry = new ZipCentralDirectoryEntry(compression, entryPath, (ulong)streamPosition)
                         {
                             Comment = options.EntryComment,
-                            FileName = entryPath,
-                            ModificationTime = options.ModificationDateTime,
-                            HeaderOffset = (ulong)streamPosition
-			};
+                            ModificationTime = options.ModificationDateTime
+                        };
 
             // Use the archive default setting for zip64 and allow overrides
             var useZip64 = isZip64;
@@ -126,8 +126,7 @@ public Stream WriteToStream(string entryPath, ZipWriterEntryOptions options)
 
             var headersize = (uint)WriteHeader(entryPath, options, entry, useZip64);
             streamPosition += headersize;
-            return new ZipWritingStream(this, OutputStream, entry, 
-                ToZipCompressionMethod(options.CompressionType ?? compressionType), 
+            return new ZipWritingStream(this, OutputStream, entry, compression, 
                 options.DeflateCompressionLevel ?? compressionLevel);
         }