[Swift] Object API support (#5826)

* Adds Object-api support to swift

* Fixed indentation issues

* Removed indentation within namespaces

swift/Sources/FlatBuffers/ByteBuffer.swift

@@ -131,6 +131,16 @@ public struct ByteBuffer {
             push(value: s, len: MemoryLayout.size(ofValue: s))
         }
     }
+    
+    ///Adds an array of type Bool to the buffer memory
+    /// - Parameter elements: An array of Bool
+    @usableFromInline mutating func push(elements: [Bool]) {
+        let size = elements.count * MemoryLayout<Bool>.size
+        ensureSpace(size: UInt32(size))
+        elements.lazy.reversed().forEach { (s) in
+            push(value: s ? 1 : 0, len: MemoryLayout.size(ofValue: s))
+        }
+    }
 
     /// A custom type of structs that are padded according to the flatbuffer padding,
     /// - Parameters:
@@ -174,8 +184,6 @@ public struct ByteBuffer {
     ///   - len: Size of string
     @usableFromInline mutating internal func push(bytes: UnsafeBufferPointer<String.UTF8View.Element>, len: Int) -> Bool {
         memcpy(_storage.memory.advanced(by: writerIndex - len), UnsafeRawPointer(bytes.baseAddress!), len)
-//        _memory.advanced(by: writerIndex - len).copyMemory(from:
-//            UnsafeRawPointer(bytes.baseAddress!), byteCount: len)
         _writerSize += len
         return true
     }

swift/Sources/FlatBuffers/FlatBufferBuilder.swift

@@ -53,7 +53,7 @@ public struct FlatBufferBuilder {
     /// Returns A sized Buffer from the readable bytes
     public var sizedBuffer: ByteBuffer {
         assert(finished, "Data shouldn't be called before finish()")
-        return ByteBuffer(memory: _bb.memory.advanced(by: _bb.reader), count: _bb.reader)
+        return ByteBuffer(memory: _bb.memory.advanced(by: _bb.reader), count: Int(_bb.size))
     }
     
     // MARK: - Init
@@ -276,6 +276,24 @@ public struct FlatBufferBuilder {
         return push(element: Int32(len))
     }
     
+    /// Creates a vector of type Bool in the buffer
+    /// - Parameter elements: elements to be written into the buffer
+    /// - returns: Offset of the vector
+    mutating public func createVector(_ elements: [Bool]) -> Offset<UOffset> {
+        return createVector(elements, size: elements.count)
+    }
+    
+    ///  Creates a vector of type Bool in the buffer
+    /// - Parameter elements: Elements to be written into the buffer
+    /// - Parameter size: Count of elements
+    /// - returns: Offset of the vector
+    mutating public func createVector(_ elements: [Bool], size: Int) -> Offset<UOffset> {
+        let size = size
+        startVector(size, elementSize: MemoryLayout<Bool>.size)
+        _bb.push(elements: elements)
+        return Offset(offset: endVector(len: size))
+    }
+    
     /// Creates a vector of type Scalar in the buffer
     /// - Parameter elements: elements to be written into the buffer
     /// - returns: Offset of the vector

swift/Sources/FlatBuffers/FlatBufferObject.swift

@@ -6,6 +6,14 @@ public protocol FlatBufferObject {
     init(_ bb: ByteBuffer, o: Int32)
 }
 
+public protocol NativeTable {}
+
+public protocol ObjectAPI {
+    associatedtype T
+    static func pack(_ builder: inout FlatBufferBuilder, obj: inout T) -> Offset<UOffset>
+    mutating func unpack() -> T
+}
+
 /// Readable is structures all the Flatbuffers structs
 ///
 /// Readable is a procotol that each Flatbuffer struct should confirm to since