Better reporting of partial lines, including leaving out partial stuff altogether if no arcs were measured.

1 files changed, 5 insertions, 0 deletions

diff --git a/coverage/data.py b/coverage/data.py
index a4bc6086..72ce38fd 100644
--- a/coverage/data.py
+++ b/coverage/data.py
@@ -219,6 +219,11 @@ class CoverageData(object):
             summ[filename_fn(filename)] = len(lines)
         return summ
 
+    def has_arcs(self):
+        """Does this data have arcs?"""
+        return bool(self.arcs)
+
+
 if __name__ == '__main__':
     # Ad-hoc: show the raw data in a data file.
     import pprint, sys