CPP: Tag metric filter queries.

Author: geoffw0

cpp/ql/src/external/examples/filters/BumpMetricBy10.ql

@@ -3,6 +3,7 @@
  * @description This filter demonstrates how to change the value
  *              computed by the metric that it is filtering. In this
  *              example the value is increased by 10.
+ * @tags filter
  */
 import cpp
 import external.MetricFilter

cpp/ql/src/external/tests/MetricFilter.ql

@@ -1,6 +1,7 @@
 /**
  * @name Metric filter
  * @description Only include results in large files (200) lines of code.
+ * @tags filter
  */
 import cpp
 import external.MetricFilter

cpp/ql/src/filters/FilterAutogeneratedForMetric.ql

@@ -4,6 +4,7 @@
  *              located in files that are maintained manually.
  * @kind treemap
  * @id cpp/autogenerated-for-metric-filter
+ * @tags filter
  */
 
 import cpp

cpp/ql/src/filters/RecentDefectsForMetric.ql

@@ -6,6 +6,7 @@
  *              before the snapshot.
  * @kind treemap
  * @id cpp/recent-defects-for-metric-filter
+ * @tags filter
  * @deprecated
  */
 import cpp