1 files changed, 66 insertions, 2 deletions
diff --git a/test/test_data.py b/test/test_data.py
index 6e3d13f0..04dd9f28 100644
--- a/test/test_data.py
+++ b/test/test_data.py
@@ -3,8 +3,72 @@
 from coverage.data import CoverageData
 from coveragetest import CoverageTest
 
+try:
+    set()
+except:
+    from sets import Set as set
+
+DATA_1 = [ ('a.py',1), ('a.py',2), ('b.py',3) ]
+SUMMARY_1 = { 'a.py':2, 'b.py':1 }
+EXECED_FILES_1 = [ 'a.py', 'b.py' ]
+
+DATA_2 = [ ('a.py',1), ('a.py',5), ('c.py',17) ]
+SUMMARY_1_2 = { 'a.py':3, 'b.py':1, 'c.py':1 }
+EXECED_FILES_1_2 = [ 'a.py', 'b.py', 'c.py' ]
+
 class DataTest(CoverageTest):
-    def test_reading(self):
+    
+    def assert_summary(self, covdata, summary):
+        self.assertEqual(covdata.summary(), summary)
+        
+    def assert_executed_files(self, covdata, execed):
+        e1 = set(covdata.executed_files())
+        e2 = set(execed)
+        self.assertEqual(e1, e2)
+    
+    def test_reading_empty(self):
         covdata = CoverageData()
         covdata.read()
-        self.assertEqual(covdata.summary(), {})
+        self.assert_summary(covdata, {})
+
+    def test_adding_data(self):
+        covdata = CoverageData()
+        covdata.add_line_data(DATA_1)
+        self.assert_summary(covdata, SUMMARY_1)
+        self.assert_executed_files(covdata, EXECED_FILES_1)
+        
+    def test_writing_and_reading(self):
+        covdata1 = CoverageData()
+        covdata1.add_line_data(DATA_1)
+        covdata1.write()
+        
+        covdata2 = CoverageData()
+        covdata2.read()
+        self.assert_summary(covdata2, SUMMARY_1)
+
+    def test_combining(self):
+        covdata1 = CoverageData()
+        covdata1.set_suffix('1')
+        covdata1.add_line_data(DATA_1)
+        covdata1.write()
+        
+        covdata2 = CoverageData()
+        covdata2.set_suffix('2')
+        covdata2.add_line_data(DATA_2)
+        covdata2.write()
+        
+        covdata3 = CoverageData()
+        covdata3.combine_parallel_data()
+        self.assert_summary(covdata3, SUMMARY_1_2)
+        self.assert_executed_files(covdata3, EXECED_FILES_1_2)
+
+    def test_erasing(self):
+        covdata1 = CoverageData()
+        covdata1.add_line_data(DATA_1)
+        covdata1.write()
+        covdata1.erase()
+        self.assert_summary(covdata1, {})
+        
+        covdata2 = CoverageData()
+        covdata2.read()
+        self.assert_summary(covdata2, {})