Split GM json schema out of display_json_results.py, for sharing with other tools

gm/gm_json.py

 #!/usr/bin/env python
 # Copyright (c) 2013 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.
 
-"""Utility to display a summary of JSON-format GM results, and exit with
-a nonzero errorcode if there were non-ignored failures in the GM results.
+"""Schema of the JSON summary file written out by the GM tool.
 
-Usage:
-  python display_json_results.py <filename>
-
-TODO(epoger): We may want to add flags to set the following:
-- which error types cause a nonzero return code
-- maximum number of tests to list for any one ResultAccumulator
-  (to keep the output reasonably short)
+This must be kept in sync with the kJsonKey_ constants in gm_expectations.cpp !
 """
 
 __author__ = 'Elliot Poger'
 
 
+# system-level imports
 import json
-import sys
 
 
 # These constants must be kept in sync with the kJsonKey_ constants in
 # gm_expectations.cpp !
 JSONKEY_ACTUALRESULTS = 'actual-results'
 JSONKEY_ACTUALRESULTS_FAILED = 'failed'
 JSONKEY_ACTUALRESULTS_FAILUREIGNORED = 'failure-ignored'
 JSONKEY_ACTUALRESULTS_NOCOMPARISON = 'no-comparison'
 JSONKEY_ACTUALRESULTS_SUCCEEDED = 'succeeded'
 
-
-class ResultAccumulator(object):
-  """Object that accumulates results of a given type, and can generate a
-     summary upon request."""
-
-  def __init__(self, name, do_list, do_fail):
-    """name: name of the category this result type falls into
-       do_list: whether to list all of the tests with this results type
-       do_fail: whether to return with nonzero exit code if there are any
-                results of this type
-    """
-    self._name = name
-    self._do_list = do_list
-    self._do_fail = do_fail
-    self._testnames = []
-
-  def AddResult(self, testname):
-    """Adds a result of this particular type.
-       testname: (string) name of the test"""
-    self._testnames.append(testname)
-
-  def ShouldSignalFailure(self):
-    """Returns true if this result type is serious (self._do_fail is True)
-       and there were any results of this type."""
-    if self._do_fail and self._testnames:
-      return True
-    else:
-      return False
-
-  def GetSummaryLine(self):
-    """Returns a single-line string summary of all results added to this
-       accumulator so far."""
-    summary = ''
-    if self._do_fail:
-      summary += '[*] '
-    else:
-      summary += '[ ] '
-    summary += str(len(self._testnames))
-    summary += ' '
-    summary += self._name
-    if self._do_list:
-      summary += ': '
-      for testname in self._testnames:
-        summary += testname
-        summary += ' '
-    return summary
-
-
-def Display(filepath):
-  """Displays a summary of the results in a JSON file.
-     Returns True if the results are free of any significant failures.
-     filepath: (string) path to JSON file"""
-
-  # Map labels within the JSON file to the ResultAccumulator for each label.
-  results_map = {
-    JSONKEY_ACTUALRESULTS_FAILED:
-        ResultAccumulator(name='ExpectationsMismatch',
-                          do_list=True, do_fail=True),
-    JSONKEY_ACTUALRESULTS_FAILUREIGNORED:
-        ResultAccumulator(name='IgnoredExpectationsMismatch',
-                          do_list=True, do_fail=False),
-    JSONKEY_ACTUALRESULTS_NOCOMPARISON:
-        ResultAccumulator(name='MissingExpectations',
-                          do_list=False, do_fail=False),
-    JSONKEY_ACTUALRESULTS_SUCCEEDED:
-        ResultAccumulator(name='Passed',
-                          do_list=False, do_fail=False),
-  }
-
-  success = True
+def Load(filepath):
+  """Loads the JSON summary written out by the GM tool.
+     Returns a dictionary keyed by the values listed as JSONKEY_ constants
+     above."""
+  # In the future, we should add a version number to the JSON file to ensure
+  # that the writer and reader agree on the schema (raising an exception
+  # otherwise).
   json_dict = json.load(open(filepath))
-  actual_results = json_dict[JSONKEY_ACTUALRESULTS]
-  for label, accumulator in results_map.iteritems():
-    results = actual_results[label]
-    if results:
-      for result in results:
-        accumulator.AddResult(result)
-    print accumulator.GetSummaryLine()
-    if accumulator.ShouldSignalFailure():
-      success = False
-  print '(results marked with [*] will cause nonzero return value)'
-  return success
-
-
-if '__main__' == __name__:
-  if len(sys.argv) != 2:
-    raise Exception('usage: %s <input-json-filepath>' % sys.argv[0])
-  sys.exit(0 if Display(sys.argv[1]) else 1)
+  return json_dict