Yikes: when using the Python tracing function, we haven't been caching the results of should_trace since <<changeset a480f40d1fa4>>

1 files changed, 4 insertions, 1 deletions

diff --git a/coverage/collector.py b/coverage/collector.py
index 06ccda7e..55211f2a 100644
--- a/coverage/collector.py
+++ b/coverage/collector.py
@@ -60,7 +60,10 @@ class PyTracer(object):
             # in this file.
             self.data_stack.append((self.cur_file_data, self.last_line))
             filename = frame.f_code.co_filename
-            tracename = self.should_trace(filename, frame)
+            tracename = self.should_trace_cache.get(filename)
+            if tracename is None:
+                tracename = self.should_trace(filename, frame)
+                self.should_trace_cache[filename] = tracename
             if tracename:
                 if tracename not in self.data:
                     self.data[tracename] = {}