If a plugin is disabled, don't try to record its file tracers. #1011

2 files changed, 16 insertions, 1 deletions

diff --git a/coverage/collector.py b/coverage/collector.py
index 3545ab1e..9333d66a 100644
--- a/coverage/collector.py
+++ b/coverage/collector.py
@@ -196,6 +196,8 @@ class Collector(object):
         # handle them.
         self.file_tracers = {}
 
+        self.disabled_plugins = set()
+
         # The .should_trace_cache attribute is a cache from file names to
         # coverage.FileDisposition objects, or None.  When a file is first
         # considered for tracing, a FileDisposition is obtained from
@@ -419,6 +421,10 @@ class Collector(object):
 
         return dict((self.cached_mapped_file(k), v) for k, v in items if v)
 
+    def plugin_was_disabled(self, plugin):
+        """Record that `plugin` was disabled during the run."""
+        self.disabled_plugins.add(plugin._coverage_plugin_name)
+
     def flush_data(self):
         """Save the collected data to our associated `CoverageData`.
 
@@ -434,7 +440,12 @@ class Collector(object):
             self.covdata.add_arcs(self.mapped_file_dict(self.data))
         else:
             self.covdata.add_lines(self.mapped_file_dict(self.data))
-        self.covdata.add_file_tracers(self.mapped_file_dict(self.file_tracers))
+
+        file_tracers = {
+            k: v for k, v in self.file_tracers.items()
+            if v not in self.disabled_plugins
+        }
+        self.covdata.add_file_tracers(self.mapped_file_dict(file_tracers))
 
         self._clear_data()
         return True
diff --git a/coverage/control.py b/coverage/control.py
index 7c4a4828..2d75417e 100644
--- a/coverage/control.py
+++ b/coverage/control.py
@@ -709,6 +709,10 @@ class Coverage(object):
         self._init_data(suffix=None)
         self._post_init()
 
+        for plugin in self._plugins:
+            if not plugin._coverage_enabled:
+                self._collector.plugin_was_disabled(plugin)
+
         if self._collector and self._collector.flush_data():
             self._post_save_work()