Import json by default, then simplejson.

tools/perf_expectations/make_expectations.py

 #!/usr/bin/python
 # Copyright (c) 2011 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 
 import hashlib
 import math
 import optparse
 import re
-import simplejson
 import subprocess
 import sys
 import time
 import urllib2
 
 
+try:
+  import json
+except ImportError:
+  import simplejson as json
+
+
 __version__ = '1.0'
 DEFAULT_EXPECTATIONS_FILE = 'perf_expectations.json'
 DEFAULT_VARIANCE = 0.05
 USAGE = ''
 
 
 def ReadFile(filename):
   try:
     file = open(filename, 'r')
   except IOError, e:
     print >> sys.stderr, ('I/O Error reading file %s(%s): %s' %
                           (filename, e.errno, e.strerror))
     raise e
   contents = file.read()
   file.close()
   return contents
 
 
 def ConvertJsonIntoDict(string):
   """Read a JSON string and convert its contents into a Python datatype."""
   if len(string) == 0:
     print >> sys.stderr, ('Error could not parse empty string')
     raise Exception('JSON data missing')
 
   try:
-    json = simplejson.loads(string)
+    jsondata = json.loads(string)
   except ValueError, e:
     print >> sys.stderr, ('Error parsing string: "%s"' % string)
     raise e
-  return json
+  return jsondata
 
 
 # Floating point representation of last time we fetched a URL.
 last_fetched_at = None
 def FetchUrlContents(url):
   global last_fetched_at
   if last_fetched_at and ((time.time() - last_fetched_at) <= 0.5):
     # Sleep for half a second to avoid overloading the server.
     time.sleep(0.5)
   try:
@@ skipping 32 matching lines @@
   except IOError, e:
     print >> sys.stderr, ('I/O Error writing file %s(%s): %s' %
                           (filename, e.errno, e.strerror))
     return False
   jsondata = []
   for key in keys:
     rowdata = GetRowData(data, key)
 
     # Include an updated checksum.
     sha1 = hashlib.sha1()
+    rowdata = [str(possibly_unicode_string).encode('ascii')
+               for possibly_unicode_string in rowdata]
     sha1.update(str(rowdata) + key)
     rowdata.append('"sha1": "%s"' % sha1.hexdigest()[0:8])
 
     jsondata.append('"%s": {%s}' % (key, ', '.join(rowdata)))
   jsondata.append('"load": true')
-  json = '{%s\n}' % ',\n '.join(jsondata)
-  file.write(json + '\n')
+  jsontext = '{%s\n}' % ',\n '.join(jsondata)
+  file.write(jsontext + '\n')
   file.close()
   return True
 
 
 last_key_printed = None
 def Main(args):
   def OutputMessage(message, verbose_message=True):
     global last_key_printed
     if not options.verbose and verbose_message:
       return
@@ skipping 77 matching lines @@
     trace_values = {}
     traces = [tracename]
     if value_type == 'relative':
       traces += [reftracename]
     for trace in traces:
       trace_values.setdefault(trace, {})
 
     # Find the high and low values for each of the traces.
     scanning = False
     for line in summarylist:
-      json = ConvertJsonIntoDict(line)
-      if int(json['rev']) <= revb:
+      jsondata = ConvertJsonIntoDict(line)
+      if int(jsondata['rev']) <= revb:
         scanning = True
-      if int(json['rev']) < reva:
+      if int(jsondata['rev']) < reva:
         break
 
       # We found the upper revision in the range.  Scan for trace data until we
       # find the lower revision in the range.
       if scanning:
         for trace in traces:
-          if trace not in json['traces']:
+          if trace not in jsondata['traces']:
             OutputMessage('trace %s missing' % trace)
             continue
-          if type(json['traces'][trace]) != type([]):
+          if type(jsondata['traces'][trace]) != type([]):
             OutputMessage('trace %s format not recognized' % trace)
             continue
           try:
-            tracevalue = float(json['traces'][trace][0])
+            tracevalue = float(jsondata['traces'][trace][0])
           except ValueError:
             OutputMessage('trace %s value error: %s' % (
-                trace, str(json['traces'][trace][0])))
+                trace, str(jsondata['traces'][trace][0])))
             continue
 
           for bound in ['high', 'low']:
             trace_values[trace].setdefault(bound, tracevalue)
 
           trace_values[trace]['high'] = max(trace_values[trace]['high'],
                                             tracevalue)
           trace_values[trace]['low'] = min(trace_values[trace]['low'],
                                            tracevalue)
 
@@ skipping 46 matching lines @@
     WriteJson(DEFAULT_EXPECTATIONS_FILE, perf, perfkeys)
     print 'done'
   else:
     if options.verbose:
       print ''
     print 'No changes.'
 
 
 if __name__ == '__main__':
   sys.exit(Main(sys.argv))