Add packBin function and implement pack for Value.Bin

Author: Gab-km

MsgPack.Test/MsgPack.Test.fs

@@ -398,6 +398,32 @@ module PackStringTest =
         sut.Length |> assertEqualTo 16909065
         sut.[0..4] |> assertEquivalentTo [| 0xDBuy; 0x01uy; 0x02uy; 0x03uy; 0x04uy |]
 
+[<TestFixture>]
+module PackBinTest =
+    [<Test>]
+    let ``Given [| 0 .. 254 |] When packBin Then return byte[] and its format header is 0xC4 and its length is 257`` () =
+        let sut = [| 0uy .. 254uy |] |> Packer.packBin
+        sut.Length |> assertEqualTo 257
+        sut.[0..1] |> assertEquivalentTo [| 0xC4uy; 0xFFuy |]
+
+    [<Test>]
+    let ``Given [| 0 .. 255 |] When packBin Then return byte[] and its format header is 0xC5 and its length is 259`` () =
+        let sut = [| 0uy .. 255uy |] |> Packer.packBin
+        sut.Length |> assertEqualTo 259
+        sut.[0..2] |> assertEquivalentTo [| 0xC5uy; 0x01uy; 0x00uy |]
+
+    [<Test>]
+    let ``Given 65535-length bin array When packBin Then return byte[] and its format header is 0xC5 and its length is 65538`` () =
+        let sut = Array.create 65535 0uy |> Packer.packBin
+        sut.Length |> assertEqualTo 65538
+        sut.[0..2] |> assertEquivalentTo [| 0xC5uy; 0xFFuy; 0xFFuy |]
+
+    [<Test>]
+    let ``Given 65536-length bin array When packBin Then return byte[] and its format header is 0xC6 and its length is 65541`` () =
+        let sut = Array.create 65536 0uy |> Packer.packBin
+        sut.Length |> assertEqualTo 65541
+        sut.[0..4] |> assertEquivalentTo [| 0xC6uy; 0x00uy; 0x01uy; 0x00uy; 0x00uy |]
+
 [<TestFixture>]
 module PackArrayTest =
     [<Test>]

MsgPack/MsgPack.fs

@@ -23,6 +23,9 @@ type Format =
     static member Nil = 0xC0uy
     static member False = 0xC2uy
     static member True = 0xC3uy
+    static member Bin8 = 0xC4uy
+    static member Bin16 = 0xC5uy
+    static member Bin32 = 0xC6uy
     static member Ext8 = 0xC7uy
     static member Ext16 = 0xC8uy
     static member Ext32 = 0xC9uy
@@ -286,6 +289,23 @@ module Packer =
                                    byte (length &&& 0x000000FF) |]
                                 bytes       // string whose length is greater than 2^16-1.
 
+    [<CompiledName("PackBinary")>]
+    let packBin (bs: byte[]) =
+        let length = bs.Length
+        if length <= 255 then Array.append [| Format.Bin8; byte(length) |] bs
+        elif length <= 65535 then Array.append
+                                    [| Format.Bin16
+                                       byte ((length &&& 0xFF00) >>> 8)
+                                       byte (length &&& 0x00FF) |]
+                                    bs
+        else Array.append
+                [| Format.Bin32
+                   byte ((length &&& 0xFF000000) >>> 24)
+                   byte ((length &&& 0x00FF0000) >>> 16)
+                   byte ((length &&& 0x0000FF00) >>> 8)
+                   byte (length &&& 0x000000FF) |]
+                bs
+
     [<CompiledName("PackExtended")>]
     let packExt (t: sbyte) (bs: byte[]) =
         let length = bs.Length
@@ -324,7 +344,7 @@ module Packer =
         | Value.Int32 i -> packInt i
         | Value.Int64 i -> packInt64 i
         | Value.String s -> packString s
-        | Value.Bin b -> [||]
+        | Value.Bin b -> packBin b
         | Value.Array arr ->
             let fmapped = Array.collect pack arr
             let length = arr.Length