fixup! Giant refactor to move all state into a Kernel struct

Author: JamesWrigley

src/IJulia.jl

@@ -144,7 +144,7 @@ end
     # Variable so that display can be done in the correct Msg context
     execute_msg::Msg = Msg(["julia"], Dict("username"=>"jlkernel", "session"=>uuid4()), Dict())
     # Variable tracking the number of bytes written in the current execution request
-    stdio_bytes::RefValue{Int} = Ref(0)
+    stdio_bytes::Int = 0
     # Use an array to accumulate "payloads" for the execute_reply message
     execute_payloads::Vector{Dict} = Dict[]
 
@@ -467,7 +467,7 @@ function clear_output(wait=false, kernel=_default_kernel)
     empty!(kernel.displayqueue) # discard pending display requests
     send_ipython(kernel.publish[], kernel, msg_pub(kernel.execute_msg::Msg, "clear_output",
                                            Dict("wait" => wait)))
-    kernel.stdio_bytes[] = 0 # reset output throttling
+    kernel.stdio_bytes = 0 # reset output throttling
     return nothing
 end
 

src/execute_request.jl

@@ -27,7 +27,7 @@ function execute_request(socket, kernel, msg)
     code = msg.content["code"]
     @vprintln("EXECUTING ", code)
     kernel.execute_msg = msg
-    kernel.stdio_bytes[] = 0
+    kernel.stdio_bytes = 0
     silent = msg.content["silent"]
     store_history = get(msg.content, "store_history", !silent)
     empty!(kernel.execute_payloads)

src/stdio.jl

@@ -75,13 +75,13 @@ function watch_stream(rd::IO, name::AbstractString, kernel)
         while !eof(rd) # blocks until something is available
             nb = bytesavailable(rd)
             if nb > 0
-                kernel.stdio_bytes[] += nb
+                kernel.stdio_bytes += nb
                 # if this stream has surpassed the maximum output limit then ignore future bytes
-                if kernel.stdio_bytes[] >= kernel.max_output_per_request[]
+                if kernel.stdio_bytes >= kernel.max_output_per_request[]
                     read(rd, nb) # read from libuv/os buffer and discard
-                    if kernel.stdio_bytes[] - nb < kernel.max_output_per_request[]
+                    if kernel.stdio_bytes - nb < kernel.max_output_per_request[]
                         send_ipython(kernel.publish[], kernel, msg_pub(kernel.execute_msg, "stream",
-                                     Dict("name" => "stderr", "text" => "Excessive output truncated after $(kernel.stdio_bytes[]) bytes.")))
+                                     Dict("name" => "stderr", "text" => "Excessive output truncated after $(kernel.stdio_bytes) bytes.")))
                     end
                 else
                     @lock buf_lock write(buf, read(rd, nb))