1 files changed, 24 insertions, 13 deletions
diff --git a/coverage/report.py b/coverage/report.py
index 7f3e3e02..a676e186 100644
--- a/coverage/report.py
+++ b/coverage/report.py
@@ -2,48 +2,59 @@
 
 import os
 from coverage.codeunit import code_unit_factory
-from coverage.misc import NoSource
+from coverage.misc import CoverageException, NoSource
 
 class Reporter(object):
     """A base class for all reporters."""
-    
+
     def __init__(self, coverage, ignore_errors=False):
         """Create a reporter.
-        
+
         `coverage` is the coverage instance. `ignore_errors` controls how
         skittish the reporter will be during file processing.
 
         """
         self.coverage = coverage
         self.ignore_errors = ignore_errors
-        
+
         # The code units to report on.  Set by find_code_units.
         self.code_units = []
-        
+
         # The directory into which to place the report, used by some derived
         # classes.
         self.directory = None
 
-    def find_code_units(self, morfs, omit_prefixes):
+    def find_code_units(self, morfs, omit_prefixes, include_prefixes):
         """Find the code units we'll report on.
-        
+
         `morfs` is a list of modules or filenames. `omit_prefixes` is a list
         of prefixes to leave out of the list.
-        
+
+        See `coverage.report()` for other arguments.
+
         """
         morfs = morfs or self.coverage.data.executed_files()
         self.code_units = code_unit_factory(
-                            morfs, self.coverage.file_locator, omit_prefixes)
+                            morfs, self.coverage.file_locator, omit_prefixes,
+                            include_prefixes
+                            )
         self.code_units.sort()
 
     def report_files(self, report_fn, morfs, directory=None,
-                        omit_prefixes=None):
+                        omit_prefixes=None, include_prefixes=None):
         """Run a reporting function on a number of morfs.
-        
+
         `report_fn` is called for each relative morf in `morfs`.
-        
+
+        `include_prefixes` is a list of filename prefixes. CodeUnits that match
+        those prefixes will be included in the list. CodeUnits that match
+        `omit_prefixes` will be omitted from the list.
+
         """
-        self.find_code_units(morfs, omit_prefixes)
+        self.find_code_units(morfs, omit_prefixes, include_prefixes)
+
+        if not self.code_units:
+            raise CoverageException("No data to report.")
 
         self.directory = directory
         if self.directory and not os.path.exists(self.directory):