Inline variants should be able to combine with out-of-line ones

Users should be able to extend the out-of-line variants by specifying
some inline variants under the <token> node.

Bug: 758782
Change-Id: I44a91a4b694dee148435f588552c6c91d89ecdd1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2473442
Commit-Queue: Weilun Shi <sweilun@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Auto-Submit: Weilun Shi <sweilun@chromium.org>
Cr-Commit-Position: refs/heads/master@{#817754}

tools/metrics/histograms/extract_histograms.py

@@ -476,6 +476,7 @@ def _ExtractTokens(histogram, variants_dict):
       continue
 
     token = dict(key=token_key)
+    token['variants'] = []
 
     # If 'variants' attribute is set for the <token>, get the list of Variant
     # objects from from the |variants_dict|. Else, extract the <variant>
@@ -484,7 +485,7 @@ def _ExtractTokens(histogram, variants_dict):
       variants_name = token_node.getAttribute('variants')
       variant_list = variants_dict.get(variants_name)
       if variant_list:
-        token['variants'] = variant_list
+        token['variants'] = variant_list[:]
       else:
         logging.error(
             "The variants attribute %s of token key %s of histogram %s does "
@@ -492,8 +493,8 @@ def _ExtractTokens(histogram, variants_dict):
             (variants_name, token_key, histogram_name))
         token['variants'] = []
         have_error = True
-    else:
-      token['variants'] = _ExtractVariantNodes(token_node)
+    # Inline and out-of-line variants can be combined.
+    token['variants'].extend(_ExtractVariantNodes(token_node))
 
     tokens.append(token)
 

tools/metrics/histograms/extract_histograms_test.py

@@ -243,6 +243,43 @@ TEST_HISTOGRAM_VARIANTS_DUPLICATE = """
 """
 
 
+TEST_HISTOGRAM_WITH_MIXED_VARIANTS = """
+<histogram-configuration>
+<histograms>
+<variants name="HistogramNameSize">
+  <variant name=".medium" summary="medium"/>
+  <variant name=".large" summary="large"/>
+</variants>
+
+<histogram name="HistogramName.{Color}{Size}" expires_after="2017-10-16">
+  <owner>me@chromium.org</owner>
+  <summary>
+    This is a histogram for button of {Color} color and {Size} size.
+  </summary>
+  <token key="Color">
+    <variant name="red">
+      <obsolete>
+        Obsolete red
+      </obsolete>
+    </variant>
+    <variant name="green">
+      <owner>green@chromium.org</owner>
+    </variant>
+  </token>
+  <token key="Size" variants="HistogramNameSize">
+    <variant name="" summary="all"/>
+    <variant name=".small" summary="small">
+      <owner>small@chromium.org</owner>
+      <obsolete>
+        Obsolete small
+      </obsolete>
+    </variant>
+  </token>
+</histogram>
+</histograms>
+</histogram-configuration>
+"""
+
 class ExtractHistogramsTest(unittest.TestCase):
 
   def testSuffixObsoletion(self):
@@ -701,6 +738,7 @@ class ExtractHistogramsTest(unittest.TestCase):
   @parameterized.expand([
       ('InlineTokens', TEST_HISTOGRAM_WITH_TOKENS),
       ('InlineTokenAndOutOfLineVariants', TEST_HISTOGRAM_WITH_VARIANTS),
+      ('MixedVariants', TEST_HISTOGRAM_WITH_MIXED_VARIANTS),
   ])
   def testUpdateNameWithTokens(self, _, input_xml):
     histogram_with_token = xml.dom.minidom.parseString(input_xml)
@@ -725,6 +763,7 @@ class ExtractHistogramsTest(unittest.TestCase):
   @parameterized.expand([
       ('InlineTokens', TEST_HISTOGRAM_WITH_TOKENS),
       ('InlineTokenAndOutOfLineVariants', TEST_HISTOGRAM_WITH_VARIANTS),
+      ('MixedVariants', TEST_HISTOGRAM_WITH_MIXED_VARIANTS),
   ])
   def testUpdateSummaryWithTokens(self, _, input_xml):
     histogram_with_token = xml.dom.minidom.parseString(input_xml)
@@ -762,6 +801,7 @@ class ExtractHistogramsTest(unittest.TestCase):
   @parameterized.expand([
       ('InlineTokens', TEST_HISTOGRAM_WITH_TOKENS),
       ('InlineTokenAndOutOfLineVariants', TEST_HISTOGRAM_WITH_VARIANTS),
+      ('MixedVariants', TEST_HISTOGRAM_WITH_MIXED_VARIANTS),
   ])
   def testUpdateWithTokenOwner(self, _, input_xml):
     histogram_with_token = xml.dom.minidom.parseString(input_xml)
@@ -790,6 +830,7 @@ class ExtractHistogramsTest(unittest.TestCase):
   @parameterized.expand([
       ('InlineTokens', TEST_HISTOGRAM_WITH_TOKENS),
       ('InlineTokenAndOutOfLineVariants', TEST_HISTOGRAM_WITH_VARIANTS),
+      ('MixedVariants', TEST_HISTOGRAM_WITH_MIXED_VARIANTS),
   ])
   def testUpdateWithTokenObsolete(self, _, input_xml):
     histogram_with_token = xml.dom.minidom.parseString(input_xml)