Specify encoding for "open()" functions

platformio/debug/helpers.py

@@ -154,11 +154,11 @@ def is_prog_obsolete(prog_path):
     new_digest = shasum.hexdigest()
     old_digest = None
     if isfile(prog_hash_path):
-        with open(prog_hash_path) as fp:
+        with open(prog_hash_path, encoding="utf8") as fp:
             old_digest = fp.read()
     if new_digest == old_digest:
         return False
-    with open(prog_hash_path, "w") as fp:
+    with open(prog_hash_path, mode="w", encoding="utf8") as fp:
         fp.write(new_digest)
     return True
 

platformio/debug/process/gdb.py

@@ -105,7 +105,7 @@ class GDBClientProcess(DebugClientProcess):
         footer = ["echo %s\\n" % self.INIT_COMPLETED_BANNER]
         commands = banner + commands + footer
 
-        with open(dst, "w") as fp:
+        with open(dst, mode="w", encoding="utf8") as fp:
             fp.write("\n".join(self.debug_config.reveal_patterns(commands)))
 
     def stdin_data_received(self, data):