Fixed an issue when PIO Remote device monitor crashes on the first keypress // Resolve #3832

HISTORY.rst

@@ -15,6 +15,7 @@ PlatformIO Core 5
 - Improved directory interpolation (``${platformio.***_dir}``) in `"platformio.ini" <https://docs.platformio.org/page/projectconf.html>`__ configuration file (`issue #3934 <https://github.com/platformio/platformio-core/issues/3934>`_)
 - Ignore resolving of SCons variables (e.g., ``${SOURCE.get_abspath()}``) when preprocessing interpolations (`issue #3933 <https://github.com/platformio/platformio-core/issues/3933>`_)
 - Fixed an issue when the "$PROJECT_DIR" variable was not properly replaced in the `debug_server <https://docs.platformio.org/page/projectconf/section_env_debug.html#debug-server>`__ option (`issue #4086 <https://github.com/platformio/platformio-core/issues/4086>`_)
+- Fixed an issue when `PIO Remote <https://docs.platformio.org/page/plus/pio-remote.html>`__ device monitor crashes on the first keypress (`issue #3832 <https://github.com/platformio/platformio-core/issues/3832>`_)
 
 
 5.2.2 (2021-10-20)

platformio/commands/remote/client/device_monitor.py

@@ -84,7 +84,7 @@ class DeviceMonitorClient(  # pylint: disable=too-many-instance-attributes
         self._ac_id = None
         self._d_acread = None
         self._d_acwrite = None
-        self._acwrite_buffer = ""
+        self._acwrite_buffer = b""
 
     def agent_pool_ready(self):
         d = task.deferLater(
@@ -226,7 +226,7 @@ class DeviceMonitorClient(  # pylint: disable=too-many-instance-attributes
             return
 
         data = self._acwrite_buffer
-        self._acwrite_buffer = ""
+        self._acwrite_buffer = b""
         try:
             d = self.agentpool.callRemote("acwrite", self._agent_id, self._ac_id, data)
             d.addCallback(self.cb_acwrite_result)
@@ -237,4 +237,4 @@ class DeviceMonitorClient(  # pylint: disable=too-many-instance-attributes
     def cb_acwrite_result(self, result):
         assert result > 0
         if self._acwrite_buffer:
-            self.acwrite_data("")
+            self.acwrite_data(b"")