Merge pull request #847 from MihailRis/client-side-tests

client-side `--script`, `--test` support (part 1)

res/layouts/ingame_chat.xml.lua

@@ -19,7 +19,7 @@ local function update_line(line, uptime)
     end
 end
 
-events.on("core:chat", function(message)
+local core_chat_handler = events.on("core:chat", function(message)
     while #lines >= max_lines do
         document[lines[1][1]]:destruct()
         table.remove(lines, 1)
@@ -36,7 +36,7 @@ end)
 function on_open()
     if not initialized then
         initialized = true
-        
+
         document.root:setInterval(1/animation_fps * 1000, function ()
             local uptime = time.uptime()
             for _, line in ipairs(lines) do
@@ -52,3 +52,7 @@ function on_open()
         end)
     end
 end
+
+function on_destroy()
+    events.remove("core:chat", core_chat_handler)
+end

res/modules/internal/debugging.lua

@@ -148,3 +148,29 @@ function error(message, level)
     end
     __error(message, level)
 end
+
+local LoggerClass = {
+    __index = {
+        info = function (self, text)
+            debug.log(string.format("[%s] %s", self.name, text))
+        end,
+        warning = function (self, text)
+            debug.warning(string.format("[%s] %s", self.name, text))
+        end,
+        error = function (self, text)
+            debug.error(string.format("[%s] %s", self.name, text))
+        end
+    }
+}
+
+local _getinfo = debug.getinfo
+
+function debug.Logger(name)
+    if not name then
+        local source = _getinfo(2, "S").source
+        name = file.remove_ext(source)
+    else
+        name = string.format("%s:%s", file.prefix(_getinfo(2, "S").source), name)
+    end
+    return setmetatable({name=name}, LoggerClass)
+end

res/modules/internal/events.lua

@@ -14,6 +14,7 @@ function events.on(event, func)
         events.handlers[event] = {}
     end
     table.insert(events.handlers[event], func)
+    return func
 end
 
 function events.reset(event, func)
@@ -24,6 +25,14 @@ function events.reset(event, func)
     end
 end
 
+function events.remove(event, handler)
+    local handlers = events.handlers[event]
+    if not handlers then
+        return
+    end
+    table.remove_value(handlers, handler)
+end
+
 function events.remove_by_prefix(prefix)
     for name, handlers in pairs(events.handlers) do
         local actualname = name

res/modules/internal/extensions/file.lua

@@ -23,6 +23,10 @@ function file.parent(path)
     return dir
 end
 
+function file.remove_ext(path)
+    return string.format("%s/%s", file.parent(path), file.stem(path))
+end
+
 function file.path(path)
     local pos = path:find(':')
     return path:sub(pos + 1)

res/modules/internal/extensions/table.lua

@@ -59,11 +59,7 @@ end
 
 function table.extend(t1, t2)
     for i, v in pairs(t2) do
-        if type(i) == "number" then
-            t1[#t1 + 1] = v
-        else
-            t1[i] = v
-        end
+        t1[i] = v
     end
 
     return t1
@@ -201,3 +197,11 @@ function table.tostring(t)
     end
     return s..']'
 end
+
+function table.keys(t)
+    local keys = {}
+    for key, _ in pairs(t) do
+        table.insert(keys, key)
+    end
+    return keys
+end

res/modules/internal/gui_util.lua

@@ -77,15 +77,18 @@ function Element.new(docname, name)
 end
 
 -- the engine automatically creates an instance for every ui document (layout)
-local Document = {}
-function Document.new(docname)
-    return setmetatable({name=docname}, {
-        __index=function(self, k)
-            local elem = Element.new(self.name, k)
-            rawset(self, k, elem)
-            return elem
+local Document = {
+    __index=function(self, k)
+        if type(k) ~= "string" then
+            error("element id is not a string")
         end
-    })
+        local elem = Element.new(self.name, k)
+        rawset(self, k, elem)
+        return elem
+    end
+}
+function Document.new(docname)
+    return setmetatable({name=docname}, Document)
 end
 
 local RadioGroup = {}

res/modules/internal/stream_providers/bytearray.lua

@@ -0,0 +1,131 @@
+local io_stream = require "core:io_stream"
+
+local lib = { }
+
+local buffers = { }
+local positions = { }
+
+local next_descriptor = 0
+
+local function open_descriptor(buffer)
+    next_descriptor = next_descriptor + 1
+
+    buffers[next_descriptor] = buffer
+    positions[next_descriptor] = 1
+
+    return next_descriptor
+end
+
+local function require_descriptor(descriptor)
+    if not buffers[descriptor] then
+        error("unknown descriptor")
+    end
+end
+
+function lib.read(descriptor, length)
+    require_descriptor(descriptor)
+
+    local buf = buffers[descriptor]
+    local buf_length = #buf
+    local pos = positions[descriptor]
+
+    local to_read = math.min(buf_length - pos + 1, length)
+
+    if to_read <= 0 then
+        return Bytearray()
+    end
+
+    local segment = buf:slice(pos, to_read)
+
+    positions[descriptor] = pos + to_read
+
+    return segment
+end
+
+function lib.write(descriptor, data)
+    require_descriptor(descriptor)
+
+    local buf = buffers[descriptor]
+    local pos = positions[descriptor]
+
+    local buf_length = #buf
+    local data_length = #data
+
+    local end_pos = pos + data_length - 1
+
+    -- size ensuring
+    if end_pos > buf_length then
+        for i = buf_length + 1, end_pos do
+            buf[i] = 0
+        end
+    end
+
+    for i = 1, data_length do
+        buf[i + pos - 1] = data[i]
+    end
+
+    positions[descriptor] = pos + data_length
+end
+
+function lib.seek(descriptor, mode, offset)
+    require_descriptor(descriptor)
+
+    local buf = buffers[descriptor]
+    local buf_length = #buf
+
+    local base
+
+    if mode == 'b' then
+        base = 1
+    elseif mode == 'c' then
+        base = positions[descriptor]
+    elseif mode == 'e' then
+        base = buf_length + 1
+    else error('invalid seek mode') end
+
+    local new_pos = base + offset
+
+    if new_pos < 1 then
+        error('failed to seek stream')
+    end
+
+    positions[descriptor] = new_pos
+end
+
+function lib.tell(descriptor)
+    require_descriptor(descriptor)
+
+    return positions[descriptor]
+end
+
+function lib.available(descriptor)
+    require_descriptor(descriptor)
+
+    local buf = buffers[descriptor]
+    local pos = positions[descriptor]
+
+    return math.max(#buf - pos + 1, 0)
+end
+
+function lib.is_alive(descriptor)
+    return buffers[descriptor] ~= nil
+end
+
+function lib.close(descriptor)
+    require_descriptor(descriptor)
+
+    buffers[descriptor] = nil
+    positions[descriptor] = nil
+end
+
+return function(buffer, binary_mode)
+    if binary_mode == nil then
+        binary_mode = true
+    end
+
+    return io_stream.new(
+        open_descriptor(buffer),
+        binary_mode,
+        lib
+    )
+end

res/modules/internal/stream_providers/file.lua

@@ -4,15 +4,28 @@ local lib = {
     read = file.__read_descriptor,
     write = file.__write_descriptor,
     seek = file.__seek_descriptor,
+    tell = file.__tell_descriptor,
     flush = file.__flush_descriptor,
+    available = file.__available_descriptor,
     is_alive = file.__has_descriptor,
     close = file.__close_descriptor
 }
 
+local __open_descriptor = file.__open_descriptor
+file.__open_descriptor = nil
+file.__read_descriptor = nil
+file.__write_descriptor = nil
+file.__seek_descriptor = nil
+file.__tell_descriptor = nil
+file.__flush_descriptor = nil
+file.__available_descriptor = nil
+file.__has_descriptor = nil
+file.__close_descriptor = nil
+
 return function(path, mode)
     return io_stream.new(
-        file.__open_descriptor(path, mode),
+        __open_descriptor(path, mode),
         mode:find('b') ~= nil,
         lib
     )
-end
+end

res/modules/internal/stream_providers/named_pipe_unix.lua

@@ -9,6 +9,7 @@ int close(int fd);
 ssize_t read(int fd, void *buf, size_t count);
 ssize_t write(int fd, const void *buf, size_t count);
 int fcntl(int fd, int cmd, ...);
+int ioctl(int fd, unsigned long request, ...);
 
 const char *strerror(int errnum);
 ]]
@@ -20,6 +21,7 @@ local O_WRONLY   = 0x1
 local O_RDWR     = 0x2
 local O_NONBLOCK = 0x800
 local F_GETFL    = 3
+local FIONREAD   = 0x541B
 
 local function getError()
     local err = FFI.errno()
@@ -58,12 +60,16 @@ function lib.write(fd, bytearray)
     end
 end
 
-function lib.seek(fd, mode, offset)
-    error("cannot seek the named pipe")
-end
+function lib.available(fd)
+    if fd == nil or fd < 0 then return 0 end
 
-function lib.flush(fd)
-    -- no flush on unix
+    local bytes_ready = FFI.new("int[1]", 0)
+
+    if C.ioctl(fd, FIONREAD, bytes_ready) == -1 then
+        return 0
+    end
+
+    return tonumber(bytes_ready[0])
 end
 
 function lib.is_alive(fd)

res/modules/internal/stream_providers/named_pipe_windows.lua

@@ -97,14 +97,26 @@ function lib.write(handle, bytearray)
     end
 end
 
-function lib.seek(handle, mode, offset)
-    error("cannot seek the named pipe")
-end
-
 function lib.flush(handle)
     C.FlushFileBuffers(handle)
 end
 
+function lib.available(handle)
+    if handle == nil or handle == INVALID_HANDLE_VALUE then
+        return 0
+    end
+
+    local bytes_available = FFI.new("DWORD[1]")
+
+    local success = C.PeekNamedPipe(handle, nil, 0, nil, bytes_available, nil)
+
+    if success == 0 then
+        return 0
+    end
+
+    return tonumber(bytes_available[0])
+end
+
 function lib.is_alive(handle)
     if handle == nil or handle == INVALID_HANDLE_VALUE then
         return false

res/modules/internal/stream_providers/socket.lua

@@ -0,0 +1,64 @@
+local io_stream = require "core:io_stream"
+
+local lib = { }
+
+local sockets = { }
+
+local next_descriptor = 0
+
+local function open_descriptor(socket)
+    next_descriptor = next_descriptor + 1
+
+    sockets[next_descriptor] = socket
+
+    return next_descriptor
+end
+
+local function require_descriptor(descriptor)
+    if not sockets[descriptor] then
+        error("unknown descriptor")
+    end
+end
+
+function lib.read(descriptor, length)
+    require_descriptor(descriptor)
+
+    return sockets[descriptor]:recv(length)
+end
+
+function lib.write(descriptor, data)
+    require_descriptor(descriptor)
+
+    sockets[descriptor]:send(data)
+end
+
+function lib.available(descriptor)
+    require_descriptor(descriptor)
+
+    return sockets[descriptor]:available()
+end
+
+function lib.is_alive(descriptor)
+    local socket = sockets[descriptor]
+
+    return socket ~= nil and socket:is_alive()
+end
+
+function lib.close(descriptor)
+    require_descriptor(descriptor)
+
+    sockets[descriptor]:close()
+    sockets[descriptor] = nil
+end
+
+return function(socket, binary_mode)
+    if binary_mode == nil then
+        binary_mode = true
+    end
+
+    return io_stream.new(
+        open_descriptor(socket),
+        binary_mode,
+        lib
+    )
+end

res/modules/internal/test.lua

@@ -0,0 +1,139 @@
+local __app = __vc_app
+
+local function get_node_center(node)
+    local pos = node.wpos
+    local size = node.size
+    return pos[1] + size[1] / 2, pos[2] + size[2] / 2
+end
+
+local function types_check_enum(value, enum)
+    if value == nil then
+        return true, nil
+    end
+    if type(value) ~= "string" then
+        return false, string.format("string expected [%s]", table.concat(table.keys(enum), "|"))
+    end
+    return true, nil
+end
+
+local function types_check_number(value)
+    if value == nil then
+        return true, nil
+    end
+    local value_type = type(value)
+    if value_type ~= "number" then
+        return false, string.format("number expected, got %s", value_type)
+    end
+end
+
+local function check_option(t, key, func, ...)
+    local value = t[key]
+    if value == nil then
+        return nil
+    end
+    local success, message = func(value, ...)
+    if not success then
+        error(string.format("invalid option '%s': %s", key, message))
+    end
+end
+
+local buttons_enum = {
+    left = 0,
+    right = 1,
+    middle = 2,
+}
+local no_options = {}
+
+local _tick = __app.tick
+local _set_button_pressed = test.set_button_pressed
+local _set_key_pressed = test.set_key_pressed
+local _enter_text = test.enter_text
+test.set_button_pressed = nil
+test.set_key_pressed = nil
+test.enter_text = nil
+
+function test.click(node, options)
+    options = options or no_options
+
+    check_option(options, 'button', types_check_enum, buttons_enum)
+    check_option(options, 'timeout', types_check_number)
+
+    local button = buttons_enum[options.button or 'left']
+    local timeout = options.timeout or 1000
+
+    local tm = time.precise_time()
+    while (time.precise_time() - tm) * 1000 < timeout do
+        if node.exists then
+            break
+        end
+        _tick()
+    end
+    if not node.exists then
+        error(string.format("timeout %s ms exceeded: element %s does not exists",
+            math.floor(timeout), string.escape(rawget(node, 'name'))))
+    end
+
+    local center_x, center_y = get_node_center(node)
+    _set_button_pressed(button, center_x, center_y, true)
+    _tick()
+    _set_button_pressed(button, center_x, center_y, false)
+    _tick()
+end
+
+-- TODO: replace with resolving in C++ side
+function test.find_by_attr(node, attr, value)
+    if getmetatable(node) == Document then
+        return test.find_by_attr(node.root, attr, value)
+    end
+    if node[attr] == value then
+        return node
+    end
+    local i = 1
+    while true do
+        local subnode = node[i]
+        if subnode == nil then
+            break
+        end
+        local found = test.find_by_attr(subnode, attr, value)
+        if found then
+            return found
+        end
+        i = i + 1
+    end
+end
+
+function test.find_by_text(node, text)
+    return test.find_by_attr(node, "text", text)
+end
+
+function test.find_by_attr_presence(node, attr)
+    if node[attr] then
+        return node
+    end
+    local i = 1
+    while true do
+        local subnode = node[i]
+        if subnode == nil then
+            break
+        end
+        local found = test.find_by_attr_presence(subnode, attr)
+        if found then
+            return found
+        end
+        i = i + 1
+    end
+end
+
+function test.fill(node, text, options)
+    test.click(node, options)
+    __app.tick()
+    _enter_text(text)
+    test.press("enter")
+end
+
+function test.press(key)
+    _set_key_pressed(key, true)
+    __app.tick()
+    _set_key_pressed(key, false)
+    __app.tick()
+end

res/modules/io_stream.lua

@@ -25,13 +25,13 @@ local ALL_FLUSH_MODES = {
 local CR = string.byte('\r')
 local LF = string.byte('\n')
 
-local function readFully(result, readFunc)
+local function read_fully(result, read_func)
     local isTable = type(result) == "table"
 
     local buf
 
     repeat
-        buf = readFunc(MAX_BUFFER_SIZE)
+        buf = read_func(MAX_BUFFER_SIZE)
 
         if isTable then
             for i = 1, #buf do
@@ -42,41 +42,46 @@ local function readFully(result, readFunc)
 end
 
 --[[
-
 descriptor - descriptor of stream for provided I/O library
 binaryMode - if enabled, most methods will expect bytes instead of strings
 ioLib - I/O library. Should include the following functions:
     read(descriptor: int, length: int) -> Bytearray
         May return bytearray with a smaller size if bytes have not arrived yet or have run out
+        May throw error if descriptor isn't readable
     write(descriptor: int, data: Bytearray)
-    flush(descriptor: int)
+        May throw error if descriptor isn't writeable
+    [optional] seek(descriptor: int, mode: string, offset: int)
+        Mode may be 'b' (relative begin), 'c' (relative current), 'e' (relative end + 1)
+    [optional] tell(descriptor: int) -> int
+    [optional] flush(descriptor: int)
+    [optional] available(descriptor: int) -> int
     is_alive(descriptor: int) -> bool
     close(descriptor: int)
 --]]
 
-function io_stream.new(descriptor, binaryMode, ioLib, mode, flushMode)
+function io_stream.new(descriptor, binary_mode, io_lib, mode, flush_mode)
     mode = mode or DEFAULT_MODE
-    flushMode = flushMode or FLUSH_MODE_ALL
+    flush_mode = flush_mode or FLUSH_MODE_ALL
 
     local self = setmetatable({}, io_stream)
 
     self.descriptor = descriptor
-    self.binaryMode = binaryMode
-    self.maxBufferSize = MAX_BUFFER_SIZE
-    self.ioLib = ioLib
+    self.binary_mode = binary_mode
+    self.max_buffer_size = MAX_BUFFER_SIZE
+    self.io_lib = io_lib
 
     self:set_mode(mode)
-    self:set_flush_mode(flushMode)
+    self:set_flush_mode(flush_mode)
 
     return self
 end
 
 function io_stream:is_binary_mode()
-    return self.binaryMode
+    return self.binary_mode
 end
 
-function io_stream:set_binary_mode(binaryMode)
-    self.binaryMode = binaryMode ~= nil
+function io_stream:set_binary_mode(binary_mode)
+    self.binary_mode = binary_mode ~= nil
 end
 
 function io_stream:get_mode()
@@ -88,124 +93,141 @@ function io_stream:set_mode(mode)
         error("invalid stream mode: "..mode)
     end
 
-    if self.mode == BUFFERED_MODE then
-        self.writeBuffer:clear()
-        self.readBuffer:clear()
+    if self.write_buffer then
+        self.write_buffer:clear()
+        self.write_buffer = nil
     end
 
-    if mode == BUFFERED_MODE and not self.writeBuffer then
-        self.writeBuffer = Bytearray()
-        self.readBuffer = Bytearray()
+    if self.read_buffer then
+        self.read_buffer:clear()
+        self.read_buffer = nil
+    end
+
+    if mode == BUFFERED_MODE then
+        self.write_buffer = Bytearray(self.max_buffer_size)
+        self.read_buffer = Bytearray(self.max_buffer_size)
     end
 
     self.mode = mode
 end
 
 function io_stream:get_flush_mode()
-    return self.flushMode
+    return self.flush_mode
 end
 
-function io_stream:set_flush_mode(flushMode)
-    if not table.has(ALL_FLUSH_MODES, flushMode) then
-        error("invalid flush mode: "..flushMode)
+function io_stream:set_flush_mode(flush_mode)
+    if not table.has(ALL_FLUSH_MODES, flush_mode) then
+        error("invalid flush mode: " .. flush_mode)
     end
 
-    self.flushMode = flushMode
+    self.flush_mode = flush_mode
 end
 
 function io_stream:get_max_buffer_size()
-    return self.maxBufferSize
+    return self.max_buffer_size
 end
 
-function io_stream:set_max_buffer_size(maxBufferSize)
-    self.maxBufferSize = maxBufferSize
+function io_stream:set_max_buffer_size(max_buffer_size)
+    self.max_buffer_size = max_buffer_size
+
+    self.write_buffer = Bytearray(self.max_buffer_size)
+    self.read_buffer = Bytearray(self.max_buffer_size)
 end
 
 function io_stream:available(length)
+    local available = self.io_lib.available and self.io_lib.available(self.descriptor) or 0
+
     if self.mode == BUFFERED_MODE then
-        self:__update_read_buffer()
+        available = available + #self.read_buffer
+    end
 
-        if not length then
-            return #self.readBuffer
-        else
-            return #self.readBuffer >= length
-        end
+    if not length then
+        return available
+    else
+        return available >= length
     end
 end
 
-function io_stream:__update_read_buffer()
-    local readed = Bytearray()
-
-    readFully(readed, function(length) return self.ioLib.read(self.descriptor, length) end)
-
-    self.readBuffer:append(readed)
-
-    if #self.readBuffer > self.maxBufferSize then
-        error "buffer overflow"
-    end
-end
-
-function io_stream:__read(length)
+function io_stream:__read(length, from_read_fully)
     if self.mode == YIELD_MODE then
+        if from_read_fully then
+            return self.io_lib.read(self.descriptor, length)
+        end
+
         local buffer = Bytearray()
 
         while #buffer < length do
-            buffer:append(self.ioLib.read(self.descriptor, length - #buffer))
+            buffer:append(self.io_lib.read(self.descriptor, length - #buffer))
 
             if #buffer < length then coroutine.yield() end
         end
 
         return buffer
     elseif self.mode == BUFFERED_MODE then
-        self:__update_read_buffer()
+        local buf_len = #self.read_buffer
 
-        if #self.readBuffer < length then
-            error "buffer underflow"
+        if buf_len < length then
+            self.read_buffer:append(
+                self.io_lib.read(self.descriptor, self.max_buffer_size - buf_len)
+            )
         end
 
-        local copy
+        buf_len = #self.read_buffer
 
-        if #self.readBuffer == length then
-            copy = Bytearray()
-            
-            copy:append(self.readBuffer)
+        length = math.min(buf_len, length)
 
-            self.readBuffer:clear()
+        local copy = self.read_buffer:slice(1, length)
+
+        if buf_len == length then
+            self.read_buffer:clear()
         else
-            copy = Bytearray()
-
-            for i = 1, length do
-                copy[i] = self.readBuffer[i]
-            end
-
-            self.readBuffer:remove(1, length)
+            self.read_buffer:remove(1, length)
         end
 
         return copy
     elseif self.mode == DEFAULT_MODE then
-        return self.ioLib.read(self.descriptor, length)
+        return self.io_lib.read(self.descriptor, length)
     end
 end
 
 function io_stream:__write(data)
     if self.mode == BUFFERED_MODE then
-        self.writeBuffer:append(data)
+        local data_length = #data
 
-        if #self.writeBuffer > self.maxBufferSize then
-            error "buffer overflow"
+        if #self.write_buffer + data_length > self.max_buffer_size then
+            self:flush()
         end
+
+        if data_length > self.max_buffer_size then
+            local to_write = math.floor(data_length / self.max_buffer_size) * self.max_buffer_size
+            local to_save = data_length - to_write
+
+            self.io_lib.write(self.descriptor, data:slice(1, to_write))
+
+            self:flush()
+
+            self.write_buffer = data:slice(to_write + 1, to_save)
+        else self.write_buffer:append(data) end
     elseif self.mode == DEFAULT_MODE or self.mode == YIELD_MODE then
-        return self.ioLib.write(self.descriptor, data)
+        return self.io_lib.write(self.descriptor, data)
     end
 end
 
-function io_stream:read_fully(useTable)
-    if self.binaryMode then
-        local result = useTable and Bytearray() or { }
+function io_stream:read_fully(use_table)
+    if self.binary_mode then
+        local result = use_table and { } or Bytearray()
 
-        readFully(result, function() return self:__read(self.maxBufferSize) end)
+        local avail = self:available()
+
+        if avail == 0 then
+            avail = self.max_buffer_size
+        end
+
+        read_fully(result, function() return self:__read(avail, true) end)
+
+        return result
     else
-        if useTable then
+        if use_table then
             local lines = { }
 
             local line
@@ -220,7 +242,7 @@ function io_stream:read_fully(useTable)
         else
             local result = Bytearray()
 
-            readFully(result, function() return self:__read(self.maxBufferSize) end)
+            read_fully(result, function() return self:__read(self.max_buffer_size) end)
 
             return utf8.tostring(result)
         end
@@ -262,57 +284,61 @@ function io_stream:write_line(str)
     self:__write(utf8.tobytes(str .. "\n"))
 end
 
-function io_stream:read(arg, useTable)
-    local argType = type(arg)
+function io_stream:read(arg, use_table)
+    local arg_type = type(arg)
 
-    if self.binaryMode then
-        local byteArr
+    if self.binary_mode then
+        local byte_arr
 
-        if argType == "number" then
+        if arg_type == "number" then
             -- using 'arg' as length
 
-            byteArr = self:__read(arg)
+            byte_arr = self:__read(arg)
 
-            if useTable == true then
+            if use_table == true then
                 local t = { }
 
-                for i = 1, #byteArr do
-                    t[i] = byteArr[i]
+                for i = 1, #byte_arr do
+                    t[i] = byte_arr[i]
                 end
 
                 return t
             else
-                return byteArr
+                return byte_arr
             end
-        elseif argType == "string" then
+        elseif arg_type == "string" then
             return byteutil.unpack(
                 arg,
                 self:__read(byteutil.get_size(arg))
             )
-        elseif argType == nil then
+        elseif arg_type == "nil" then
             error(
                 "in binary mode the first argument must be a string data format"..
                 " for the library \"byteutil\" or the number of bytes to read"
             )
         else
-            error("unknown argument type: "..argType)
+            error("unknown argument type: "..arg_type)
         end
     else
         if not arg then
             return self:read_line()
         else
-            local linesCount = arg
-            local trimLastEmptyLines = useTable or true
+            local lines_count = arg
+            local trim_last_empty_lines = use_table
 
-            if linesCount < 0 then error "count of lines to read must be positive" end
+            if use_table == nil then
+                trim_last_empty_lines = true
+            end
+
+            if lines_count < 0 then error "count of lines to read must be positive" end
 
             local result = { }
 
-            for i = 1, linesCount do
+            for i = 1, lines_count do
                 result[i] = self:read_line()
             end
 
-            if trimLastEmptyLines then
+            if trim_last_empty_lines then
                 local i = #result
 
                 while i >= 0 do
@@ -340,41 +366,53 @@ function io_stream:read(arg, useTable)
 end
 
 function io_stream:write(arg, ...)
-    local argType = type(arg)
+    local arg_type = type(arg)
 
-    if self.binaryMode then
-        local byteArr
+    if self.binary_mode then
+        local byte_arr
 
-        if argType ~= "string" then
+        if arg_type ~= "string" then
             -- using arg as bytes table/bytearray
 
-            if argType == "table" then
-                byteArr = Bytearray(arg)
+            if arg_type == "table" then
+                byte_arr = Bytearray(arg)
             else
-                byteArr = arg
+                byte_arr = arg
             end
         else
-            byteArr = byteutil.pack(arg, ...)
+            byte_arr = byteutil.pack(arg, ...)
         end
 
-        self:__write(byteArr)
+        self:__write(byte_arr)
     else
-        if argType == "string" then
+        if arg_type == "string" then
             self:write_line(arg)
-        elseif argType == "table" then
+        elseif arg_type == "table" then
             for i = 1, #arg do
                 self:write_line(arg[i])
             end
-        else error("unknown argument type: "..argType) end
+        else error("unknown argument type: "..arg_type) end
     end
 end
 
 function io_stream:seek(mode, offset)
-    self.ioLib.seek(self.descriptor, mode, offset)
+    if not self.io_lib.seek then
+        error("cannot seek this stream")
+    end
+
+    self.io_lib.seek(self.descriptor, mode, offset)
+end
+
+function io_stream:tell()
+    if not self.io_lib.tell then
+        error("cannot tell this stream")
+    end
+
+    return self.io_lib.tell(self.descriptor)
 end
 
 function io_stream:is_alive()
-    return self.ioLib.is_alive(self.descriptor)
+    return self.io_lib.is_alive(self.descriptor)
 end
 
 function io_stream:is_closed()
@@ -383,20 +421,24 @@ end
 
 function io_stream:close()
     if self.mode == BUFFERED_MODE then
-        self.readBuffer:clear()
-        self.writeBuffer:clear()
+        self.read_buffer:clear()
+        self.write_buffer:clear()
     end
 
-    return self.ioLib.close(self.descriptor)
+    return self.io_lib.close(self.descriptor)
 end
 
 function io_stream:flush()
-    if self.mode == BUFFERED_MODE and #self.writeBuffer > 0 then
-        self.ioLib.write(self.descriptor, self.writeBuffer)
-        self.writeBuffer:clear()
+    if self.mode == BUFFERED_MODE and #self.write_buffer > 0 then
+        self.io_lib.write(self.descriptor, self.write_buffer)
+        self.write_buffer:clear()
     end
 
-    if self.flushMode ~= FLUSH_MODE_ONLY_BUFFER then self.ioLib.flush(self.descriptor) end
+    if self.flush_mode ~= FLUSH_MODE_ONLY_BUFFER then
+        if self.io_lib.flush then
+            self.io_lib.flush(self.descriptor)
+        elseif self:is_closed() then error("stream is closed") end
+    end
 end
 
 return io_stream

res/scripts/classes.lua

@@ -49,6 +49,7 @@ local Socket = {__index={
         end
         return self:recv(length, usetable)
     end,
+    as_stream=network.__as_stream,
     close=function(self) return network.__close(self.id) end,
     available=function(self) return network.__available(self.id) or 0 end,
     is_alive=function(self) return network.__is_alive(self.id) end,

res/scripts/stdlib.lua

@@ -127,6 +127,10 @@ require "core:internal/extensions/inventory"
 asserts = require "core:internal/asserts"
 events = require "core:internal/events"
 
+if test then
+    require "core:internal/test"
+end
+
 function pack.unload(prefix)
     events.remove_by_prefix(prefix)
 end
@@ -334,6 +338,10 @@ else
     os.pid = ffi.C.getpid()
 end
 
+require("core:io_stream").wrap_bytearray = require "core:internal/stream_providers/bytearray"
+
+network.__as_stream = require "core:internal/stream_providers/socket"
+
 math.randomseed(time.uptime() * 1536227939)
 
 rules = require "core:internal/rules"