Add searching features to new TraceEventVector class for tests.

base/test/trace_event_analyzer.h

 // 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.
 
 // Use trace_analyzer::Query and trace_analyzer::TraceAnalyzer to search for
 // specific trace events that were generated by the trace_event.h API.
 //
 // Basic procedure:
 // - Get trace events JSON string from base::debug::TraceLog.
 // - Create TraceAnalyzer with JSON string.
@@ skipping 152 matching lines @@
   // All numbers and bool values from TraceEvent args are cast to double.
   // bool becomes 1.0 (true) or 0.0 (false).
   std::map<std::string, double> arg_numbers;
 
   std::map<std::string, std::string> arg_strings;
 
   // The other event associated with this event (or NULL).
   const TraceEvent* other_event;
 };
 
+typedef std::vector<const TraceEvent*> TraceEventVector;
+
 // Pass these values to Query to compare with the corresponding member of a
 // TraceEvent. Unless otherwise specfied, the usage is Query(ENUM_MEMBER).
 enum TraceEventMember {
   EVENT_INVALID,
   // Use these to access the event members:
   EVENT_PID,
   EVENT_TID,
   // Return the timestamp of the event in microseconds since epoch.
   EVENT_TIME,
   // Return the absolute time between event and other event in microseconds.
@@ skipping 228 matching lines @@
  private:
   friend class base::RefCounted<QueryNode>;
   ~QueryNode();
 
   Query query_;
 };
 
 // TraceAnalyzer helps tests search for trace events.
 class TraceAnalyzer {
  public:
-  typedef std::vector<const TraceEvent*> TraceEventVector;
-
-  struct Stats {
-    double min_us;
-    double max_us;
-    double mean_us;
-    double standard_deviation_us;
-  };
-
   ~TraceAnalyzer();
 
   // Use trace events from JSON string generated by tracing API.
   // Returns non-NULL if the JSON is successfully parsed.
   static TraceAnalyzer* Create(const std::string& json_events)
                                WARN_UNUSED_RESULT;
 
   // Associate BEGIN and END events with each other. This allows Query(OTHER_*)
   // to access the associated event and enables Query(EVENT_DURATION).
   // An end event will match the most recent begin event with the same name,
@@ skipping 27 matching lines @@
   //
   // NOTE: AssociateEvents will overwrite existing other_event associations if
   // the queries pass for events that already had a previous association.
   //
   // After calling FindEvents or FindOneEvent, it is not allowed to call
   // AssociateEvents again.
   void AssociateEvents(const Query& first,
                        const Query& second,
                        const Query& match);
 
+  // For each event, copy its arguments to the other_event argument map. If
+  // argument name already exists, it will not be overwritten.
+  void MergeAssociatedEventArgs();
+
   // Find all events that match query and replace output vector.
   size_t FindEvents(const Query& query, TraceEventVector* output);
 
   // Helper method: find first event that matches query
   const TraceEvent* FindOneEvent(const Query& query);
 
   const std::string& GetThreadName(const TraceEvent::ProcessThreadID& thread);
 
-  // Calculate min/max/mean and standard deviation from the times between
-  // adjacent events.
-  static bool GetRateStats(const TraceEventVector& events, Stats* stats);
-
  private:
   TraceAnalyzer();
 
   bool SetEvents(const std::string& json_events) WARN_UNUSED_RESULT;
 
   // Read metadata (thread names, etc) from events.
   void ParseMetadata();
 
   std::map<TraceEvent::ProcessThreadID, std::string> thread_names_;
   std::vector<TraceEvent> raw_events_;
   bool allow_assocation_changes_;
 
   DISALLOW_COPY_AND_ASSIGN(TraceAnalyzer);
 };
 
+// Utility functions for TraceEventVector.
+
+struct RateStats {
+  double min_us;
+  double max_us;
+  double mean_us;
+  double standard_deviation_us;
+};
+
+// Calculate min/max/mean and standard deviation from the times between
+// adjacent events.
+bool GetRateStats(const TraceEventVector& events, RateStats* stats);
+
+// Starting from |position|, find the first event that matches |query|.
+// Returns true if found, false otherwise.
+bool FindFirstOf(const TraceEventVector& events,
+                 Query query,
+                 size_t position,
+                 size_t* return_index);
+
+// Starting from |position|, find the last event that matches |query|.
+// Returns true if found, false otherwise.
+bool FindLastOf(const TraceEventVector& events,
+                Query query,
+                size_t position,
+                size_t* return_index);
+
+// Find the closest events to |position| in time that match |query|.
+// return_second_closest may be NULL. Closeness is determined by comparing
+// with the event timestamp.
+// Returns true if found, false otherwise. If both return parameters are
+// requested, both must be found for a successful result.
+bool FindClosest(const TraceEventVector& events,
+                 Query query,
+                 size_t position,
+                 size_t* return_closest,
+                 size_t* return_second_closest);
+
+// Count matches, inclusive of |begin_position|, exclusive of |end_position|.
+size_t CountMatches(const TraceEventVector& events,
+                    Query query,
+                    size_t begin_position,
+                    size_t end_position);
+
+// Count all matches.
+static inline size_t CountMatches(const TraceEventVector& events, Query query) {
+  return CountMatches(events, query, 0u, events.size());
+}
+
 }  // namespace trace_analyzer
 
 #endif  // BASE_TEST_TRACE_EVENT_ANALYZER_H_