improve unicode support

recipe_engine/stream.py

 # Copyright 2015 The LUCI Authors. All rights reserved.
 # Use of this source code is governed under the Apache License, Version 2.0
 # that can be found in the LICENSE file.
 
 """Abstract stream interface for representing recipe runs.
 
 We need to create streams for steps (and substeps) and also LOG_LINE steps.
 LogDog will implement LOG_LINE steps as real logs (i.e. uniformly), but
 annotations will implement them differently from normal logs, so we need
 a way to distinguish.
@@ skipping 253 matching lines @@
 
 class AnnotationStepStream(StreamEngine.StepStream):
   def __init__(self, emit_timestamps=False, time_fn=None):
     self.emit_timestamps = emit_timestamps
     self.time_fn = time_fn or time.time
 
   def basic_write(self, line):
     raise NotImplementedError()
 
   def output_annotation(self, *args):
-    self.basic_write('@@@' + '@'.join(map(str, args)) + '@@@\n')
+    self.basic_write('@@@' + '@'.join(map(unicode, args)) + '@@@\n')
 
   def write_line(self, line):
     if line.startswith('@@@'):
       self.basic_write('!' + line + '\n')
     else:
       self.basic_write(line + '\n')
 
   def close(self):
     if self.emit_timestamps:
       self.output_annotation('CURRENT_TIMESTAMP', self.time_fn())
@@ skipping 118 matching lines @@
   """A StepStream that is not tied to any engine, and emits assuming it has the
   cursor.
 
   This is used for capturing the annotations in the engine.
   """
   def __init__(self, outstream):
     self._outstream = outstream
 
   def basic_write(self, line):
     self._outstream.write(line)