Now completely unexecuted source files can be included in reporting. Specifying --source tells coverage.py where to search for files that haven't been executed.

6 files changed, 29 insertions, 2 deletions

diff --git a/CHANGES.txt b/CHANGES.txt
index cca83310..62336f6b 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -6,6 +6,10 @@ Change history for Coverage.py
 Version 3.4b2
 -------------
 
+- Completely unexecuted files can now be included in coverage results, reported
+  as 0% covered.  This only happens if the --source option is specified, since
+  coverage.py needs guidance about where to look for source files.
+
 - Coverage percentages are now displayed uniformly across reporting methods.  A
   percentage is only reported as 0% or 100% if they are truly 0 or 100, and
   are rounded otherwise.  Fixes `issue 41` and issue 70`.
diff --git a/coverage/control.py b/coverage/control.py
index dd7d705b..28c8850f 100644
--- a/coverage/control.py
+++ b/coverage/control.py
@@ -9,6 +9,7 @@ from coverage.collector import Collector
 from coverage.config import CoverageConfig
 from coverage.data import CoverageData
 from coverage.files import FileLocator, TreeMatcher, FnmatchMatcher
+from coverage.files import find_python_files
 from coverage.html import HtmlReporter
 from coverage.misc import CoverageException, bool_or_none
 from coverage.results import Analysis, Numbers
@@ -303,6 +304,7 @@ class coverage(object):
                     else:
                         pkg_file = self._source_for_file(pkg_file)
                     pkg_file = self.file_locator.canonical_filename(pkg_file)
+                    self.source.append(pkg_file)
                     self.source_match.add(pkg_file)
 
             for pkg in found:
@@ -437,6 +439,11 @@ class coverage(object):
             if not summary:
                 self._warn("No data was collected.")
 
+            # Find files that were never executed at all.
+            for src in self.source:
+                for py_file in find_python_files(src):
+                    self.data.touch_file(py_file)
+
             self._harvested = True
 
     # Backward compatibility with version 1.
diff --git a/coverage/data.py b/coverage/data.py
index 6d49f710..30119d9c 100644
--- a/coverage/data.py
+++ b/coverage/data.py
@@ -207,6 +207,10 @@ class CoverageData(object):
         for filename, arcs in arc_data.items():
             self.arcs.setdefault(filename, {}).update(arcs)
 
+    def touch_file(self, filename):
+        """Ensure that `filename` appears in the data, empty if needed."""
+        self.lines.setdefault(filename, {})
+
     def executed_files(self):
         """A list of all files that had been measured as executed."""
         return list(self.lines.keys())
diff --git a/doc/source.rst b/doc/source.rst
index e39090a4..3f0a1566 100644
--- a/doc/source.rst
+++ b/doc/source.rst
@@ -28,7 +28,9 @@ all code, unless it is part of the Python standard library.
 You can specify source to measure with the ``--source`` command-line switch,
 or the ``[run] source`` configuration value.  The value is a list of directories
 or package names.  If specified, only source inside these directories or
-packages will be measured.
+packages will be measured.  Specifying the source option also enables
+coverage.py to report on unexecuted files, since it can search the source tree
+for files that haven't been measured at all.
 
 You can further fine-tune coverage.py's attention with the ``--include`` and
 ``--omit`` switches (or ``[run] include`` and ``[run] omit`` configuration
@@ -72,4 +74,3 @@ reporting.
 Note that these are ways of specifying files to measure.  You can also exclude
 individual source lines.  See :ref:`excluding` for details.
 
-
diff --git a/test/test_api.py b/test/test_api.py
index aa6f42cd..5952dfe7 100644
--- a/test/test_api.py
+++ b/test/test_api.py
@@ -324,6 +324,8 @@ class SourceOmitIncludeTest(CoverageTest):
         self.assertEqual(lines['p1b.py'], 3)
         self.assertEqual(lines['p2a.py'], 3)
         self.assertEqual(lines['p2b.py'], 3)
+        # Because there was no source= specified, we don't search for
+        # unexecuted files.
         self.assert_('p1c.py' not in lines)
 
     def test_source_package(self):
@@ -332,6 +334,8 @@ class SourceOmitIncludeTest(CoverageTest):
         self.assertEqual(lines['p1b.py'], 3)
         self.assert_('p2a.py' not in lines)
         self.assert_('p2b.py' not in lines)
+        # Because source= was specified, we do search for unexecuted files.
+        self.assertEqual(lines['p1c.py'], 0)
 
     def test_source_package_dotted(self):
         lines = self.coverage_usepkgs_summary(source=["pkg1.p1b"])
@@ -339,6 +343,7 @@ class SourceOmitIncludeTest(CoverageTest):
         self.assertEqual(lines['p1b.py'], 3)
         self.assert_('p2a.py' not in lines)
         self.assert_('p2b.py' not in lines)
+        self.assert_('p1c.py' not in lines)
 
     def test_include(self):
         lines = self.coverage_usepkgs_summary(include=["*/p1a.py"])
diff --git a/test/test_data.py b/test/test_data.py
index 83a5b8ae..fd7e4878 100644
--- a/test/test_data.py
+++ b/test/test_data.py
@@ -45,6 +45,12 @@ class DataTest(CoverageTest):
         self.assert_summary(covdata, SUMMARY_1)
         self.assert_executed_files(covdata, EXECED_FILES_1)
 
+    def test_touch_file(self):
+        covdata = CoverageData()
+        covdata.add_line_data(DATA_1)
+        covdata.touch_file('x.py')
+        self.assert_executed_files(covdata, EXECED_FILES_1 + ['x.py'])
+
     def test_writing_and_reading(self):
         covdata1 = CoverageData()
         covdata1.add_line_data(DATA_1)