1 // Copyright 2018 The Chromium Authors 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef BASE_TEST_METRICS_HISTOGRAM_ENUM_READER_H_ 6 #define BASE_TEST_METRICS_HISTOGRAM_ENUM_READER_H_ 7 8 #include <map> 9 #include <optional> 10 #include <string> 11 12 #include "base/metrics/histogram_base.h" 13 14 namespace base { 15 16 using HistogramEnumEntryMap = std::map<HistogramBase::Sample, std::string>; 17 18 // Find and read the enum with the given |enum_name| (with integer values) from 19 // tools/metrics/histograms/enums.xml, or from enums.xml in the given 20 // |subdirectory| of tools/metrics/histograms/metadata. 21 // 22 // Returns map { value => label } so that: 23 // <int value="9" label="enable-pinch-virtual-viewport"/> 24 // becomes: 25 // { 9 => "enable-pinch-virtual-viewport" } 26 // Returns empty std::nullopt on failure. 27 std::optional<HistogramEnumEntryMap> ReadEnumFromEnumsXml( 28 const std::string& enum_name, 29 const std::optional<std::string>& subdirectory = std::nullopt); 30 31 } // namespace base 32 33 #endif // BASE_TEST_METRICS_HISTOGRAM_ENUM_READER_H_ 34