1 files changed, 72 insertions, 0 deletions
diff --git a/chromium/tools/metrics/histograms/populate_enums.py b/chromium/tools/metrics/histograms/populate_enums.py
new file mode 100644
index 00000000000..8be71a2e3f9
--- /dev/null
+++ b/chromium/tools/metrics/histograms/populate_enums.py
@@ -0,0 +1,72 @@
+# Copyright 2017 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.
+
+"""Functions for populating enums with ukm events."""
+
+from collections import namedtuple
+import os
+import sys
+import xml.dom.minidom
+
+import extract_histograms
+
+sys.path.append(os.path.join(os.path.dirname(__file__), '..', 'ukm'))
+import codegen
+
+
+EventDetails = namedtuple("EventDetails", "name hash is_obsolete")
+
+
+def _GetEventDetails(event):
+  """Returns a simple struct containing the event details.
+
+  Args:
+    event: An event.
+
+  Returns:
+    A struct containing the event name, name hash, and whether the event is
+    obsolete.
+  """
+  name = event.getAttribute('name')
+  # The value is UKM event name hash truncated to 31 bits. This is recorded in
+  # https://cs.chromium.org/chromium/src/components/ukm/ukm_recorder_impl.cc?rcl=728ad079d8e52ada4e321fb4f53713e4f0588072&l=114
+  hash = codegen.HashName(name) & 0x7fffffff
+  is_obsolete = event.getElementsByTagName('obsolete')
+  return EventDetails(name=name, hash=hash, is_obsolete=is_obsolete)
+
+
+def PopulateEnumWithUkmEvents(doc, enum, ukm_events):
+  """Populates the enum node with a list of ukm events.
+
+  Args:
+    doc: The document to create the node in.
+    enum: The enum node needed to be populated.
+    ukm_events: A list of ukm event nodes.
+  """
+  event_details = [_GetEventDetails(event) for event in ukm_events]
+  event_details.sort(key=lambda event: event.hash)
+
+  for event in event_details:
+    node = doc.createElement('int')
+    node.attributes['value'] = str(event.hash)
+    label = event.name
+    # If the event is obsolete, mark it in the int's label.
+    if event.is_obsolete:
+      label += ' (Obsolete)'
+    node.attributes['label'] = label
+    enum.appendChild(node)
+
+
+def PopulateEnumsWithUkmEvents(doc, enums, ukm_events):
+  """Populates enum nodes in the enums with a list of ukm events
+
+  Args:
+    doc: The document to create the node in.
+    enums: The enums node to be iterated.
+    ukm_events: A list of ukm event nodes.
+  """
+  for enum in extract_histograms.IterElementsWithTag(enums, 'enum', 1):
+    # We only special case 'UkmEventNameHash' currently.
+    if enum.getAttribute('name') == 'UkmEventNameHash':
+      PopulateEnumWithUkmEvents(doc, enum, ukm_events)