Plugin support for dynamic context (#783)

* Introduce a new plugin type: dynamic context labels.

* Test dynamic context plugins

* Helper method to get full paths to measured files

* Get correct filenames on all OS

* Improve wording

1 files changed, 10 insertions, 0 deletions

diff --git a/tests/coveragetest.py b/tests/coveragetest.py
index 98c1e087..c0a8fb5a 100644
--- a/tests/coveragetest.py
+++ b/tests/coveragetest.py
@@ -8,6 +8,7 @@ import datetime
 import functools
 import glob
 import os
+import os.path
 import random
 import re
 import shlex
@@ -514,6 +515,15 @@ class CoverageTest(
         """Return the last line of `report` with the spaces squeezed down."""
         return self.squeezed_lines(report)[-1]
 
+    def get_measured_filenames(self, coverage_data):
+        """Get paths to measured files.
+
+        Returns a dict of {filename: absolute path to file}
+        for given CoverageData.
+        """
+        return {os.path.basename(filename): filename
+                for filename in coverage_data.measured_files()}
+
 
 class UsingModulesMixin(object):
     """A mixin for importing modules from tests/modules and tests/moremodules."""