Implement write methods for SparseHistogram

base/metrics/sparse_histogram.h

Index: base/metrics/sparse_histogram.h
diff --git a/base/metrics/sparse_histogram.h b/base/metrics/sparse_histogram.h
index 9c207666e5d04c21fa97978438617827b7a4085f..ca1c537947a3afb9056fb24adaff5e4b1867628e 100644
--- a/base/metrics/sparse_histogram.h
+++ b/base/metrics/sparse_histogram.h
@@ -90,6 +90,27 @@ class BASE_EXPORT_PRIVATE SparseHistogram : public HistogramBase {
   virtual void GetCountAndBucketData(Count* count,
                                      ListValue* buckets) const OVERRIDE;
 
+  // Helpers for emitting Ascii graphic.  Each method appends data to output.
+  void WriteAsciiImpl(bool graph_it,
+                      const std::string& newline,
+                      std::string* output) const;
+
+  // Write a common header message describing this histogram.
+  void WriteAsciiHeader(const Count sample_count,
+                        std::string* output) const;
+
+  // Write textual description of the bucket contents (relative to histogram).
+  // Output is the count in the buckets, as well as the percentage.
+  void WriteAsciiBucketValue(const Count current, const Count total,

[jar (doing other things), 2013/04/04 00:45:09]

nit: one arg per line in declaration and definitions.

Same on line 198.

[jrummell, 2013/04/04 22:38:59]

Done.

+                             std::string* output) const;
+
+  // Produce actual graph (set of blank vs non blank char's) for a bucket.
+  void WriteAsciiBucketGraph(double current_size, double max_size,
+                             std::string* output) const;
+
+  // Return a string description of what goes in a given bucket.
+  std::string GetAsciiBucketRange(const Sample sample) const;
+
   // For constuctor calling.
   friend class SparseHistogramTest;