Better descriptions of missing one-line executables. Part of #475

1 files changed, 7 insertions, 1 deletions

diff --git a/coverage/plugin.py b/coverage/plugin.py
index 97d9c16e..a7b95466 100644
--- a/coverage/plugin.py
+++ b/coverage/plugin.py
@@ -329,9 +329,15 @@ class FileReporter(object):
         """
         return {}
 
-    def missing_arc_description(self, start, end):
+    def missing_arc_description(self, start, end, executed_arcs=None):     # pylint: disable=unused-argument
         """Provide an English sentence describing a missing arc.
 
+        The `start` and `end` arguments are the line numbers of the missing
+        arc. Negative numbers indicate entering or exiting code objects.
+
+        The `executed_arcs` argument is a set of line number pairs, the arcs
+        that were executed in this file.
+
         By default, this simply returns the string "Line {start} didn't jump
         to {end}".