A test of status.json having the wrong format

1 files changed, 22 insertions, 0 deletions

diff --git a/tests/test_html.py b/tests/test_html.py
index 1df602f2..d89d92c7 100644
--- a/tests/test_html.py
+++ b/tests/test_html.py
@@ -6,6 +6,7 @@
 
 import datetime
 import glob
+import json
 import os
 import os.path
 import re
@@ -208,6 +209,27 @@ class HtmlDeltaTest(HtmlTestHelpers, CoverageTest):
         fixed_index2 = index2.replace("XYZZY", self.real_coverage_version)
         self.assertMultiLineEqual(index1, fixed_index2)
 
+    def test_status_format_change(self):
+        self.create_initial_files()
+        self.run_coverage()
+        self.remove_html_files()
+
+        with open("htmlcov/status.json") as status_json:
+            status_data = json.load(status_json)
+
+        self.assertEqual(status_data['format'], 1)
+        status_data['format'] = 2
+        with open("htmlcov/status.json", "w") as status_json:
+            json.dump(status_data, status_json)
+
+        self.run_coverage()
+
+        # All the files have been reported again.
+        self.assert_exists("htmlcov/index.html")
+        self.assert_exists("htmlcov/helper1_py.html")
+        self.assert_exists("htmlcov/main_file_py.html")
+        self.assert_exists("htmlcov/helper2_py.html")
+
 
 class HtmlTitleTest(HtmlTestHelpers, CoverageTest):
     """Tests of the HTML title support."""