diff --git a/lib/ctt/report.py b/lib/ctt/report.py
index 6418cb0..0c1608e 100755
--- a/lib/ctt/report.py
+++ b/lib/ctt/report.py
@@ -113,16 +113,16 @@ class Report(object):
             summary_report = {}
         for project in reports:
             report, report_data = reports[project]
-            for time in report_data:
-                if summary:
+            if summary:
+                for time in report_data:
                     if not time in summary_report:
                         summary_report[time] = report_data[time]
                     else:
                         summary_report[time].extend(report_data[time])
-                else:
-                    report.header()
-                    Report.print_report_time_entries(report_data,
-                            output_format, summary)
+            else:
+                report.header()
+                Report.print_report_time_entries(report_data,
+                        output_format, summary)
         if summary:
             Report.print_report_time_entries(summary_report,
                     output_format, summary)
diff --git a/lib/ctt/test/__init__.py b/lib/ctt/test/__init__.py
new file mode 100644
index 0000000..c638736
--- /dev/null
+++ b/lib/ctt/test/__init__.py
@@ -0,0 +1,29 @@
+# -*- coding: utf-8 -*-
+#
+# 2016 Darko Poljak (darko.poljak at gmail.com))
+#
+# This file is part of ctt.
+#
+# cdist is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# cdist is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with ctt. If not, see <http://www.gnu.org/licenses/>.
+#
+#
+
+import os
+import unittest
+
+fixtures_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), "fixtures"))
+
+class CttTestCase(unittest.TestCase):
+    def setUp(self):
+        os.environ['HOME'] = fixtures_dir
diff --git a/lib/ctt/test/__main__.py b/lib/ctt/test/__main__.py
new file mode 100644
index 0000000..c257ef9
--- /dev/null
+++ b/lib/ctt/test/__main__.py
@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+#
+# 2016 Darko Poljak (darko.poljak at gmail.com)
+#
+# This file is part of ctt.
+#
+# cdist is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# cdist is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with ctt. If not, see <http://www.gnu.org/licenses/>.
+#
+#
+
+import imp
+import os
+import os.path
+import sys
+import unittest
+
+base_dir = os.path.dirname(os.path.realpath(__file__))
+
+test_modules = []
+for possible_test in os.listdir(base_dir):
+    if possible_test.startswith('test_'):
+        mod_path = os.path.join(base_dir, possible_test)
+        if os.path.isfile(mod_path):
+            module = os.path.splitext(os.path.basename(possible_test))[0]
+            test_modules.append(module)
+
+suites = []
+for test_module in test_modules:
+    module_parameters = imp.find_module(test_module, [base_dir])
+    module = imp.load_module("ctt.test." + test_module, *module_parameters)
+
+    suite = unittest.defaultTestLoader.loadTestsFromModule(module)
+    suites.append(suite)
+
+all_suites = unittest.TestSuite(suites)
+unittest.TextTestRunner(verbosity=2).run(all_suites)
diff --git a/lib/ctt/test/fixtures/.ctt/foo1/2016-04-07-0826/comment b/lib/ctt/test/fixtures/.ctt/foo1/2016-04-07-0826/comment
new file mode 100644
index 0000000..1715acd
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/foo1/2016-04-07-0826/comment
@@ -0,0 +1 @@
+foo1
diff --git a/lib/ctt/test/fixtures/.ctt/foo1/2016-04-07-0826/delta b/lib/ctt/test/fixtures/.ctt/foo1/2016-04-07-0826/delta
new file mode 100644
index 0000000..ee0c264
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/foo1/2016-04-07-0826/delta
@@ -0,0 +1 @@
+6.248274
diff --git a/lib/ctt/test/fixtures/.ctt/foo1/2016-04-08-1200/comment b/lib/ctt/test/fixtures/.ctt/foo1/2016-04-08-1200/comment
new file mode 100644
index 0000000..d8c668a
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/foo1/2016-04-08-1200/comment
@@ -0,0 +1 @@
+foo1 12
diff --git a/lib/ctt/test/fixtures/.ctt/foo1/2016-04-08-1200/delta b/lib/ctt/test/fixtures/.ctt/foo1/2016-04-08-1200/delta
new file mode 100644
index 0000000..e9c02da
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/foo1/2016-04-08-1200/delta
@@ -0,0 +1 @@
+5000
diff --git a/lib/ctt/test/fixtures/.ctt/foo2/2016-04-07-0810/comment b/lib/ctt/test/fixtures/.ctt/foo2/2016-04-07-0810/comment
new file mode 100644
index 0000000..54b060e
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/foo2/2016-04-07-0810/comment
@@ -0,0 +1 @@
+foo2
diff --git a/lib/ctt/test/fixtures/.ctt/foo2/2016-04-07-0810/delta b/lib/ctt/test/fixtures/.ctt/foo2/2016-04-07-0810/delta
new file mode 100644
index 0000000..f599e28
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/foo2/2016-04-07-0810/delta
@@ -0,0 +1 @@
+10
diff --git a/lib/ctt/test/fixtures/.ctt/foo3/2016-04-02-2110/comment b/lib/ctt/test/fixtures/.ctt/foo3/2016-04-02-2110/comment
new file mode 100644
index 0000000..c1ec6c6
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/foo3/2016-04-02-2110/comment
@@ -0,0 +1 @@
+foo3
diff --git a/lib/ctt/test/fixtures/.ctt/foo3/2016-04-02-2110/delta b/lib/ctt/test/fixtures/.ctt/foo3/2016-04-02-2110/delta
new file mode 100644
index 0000000..98330a4
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/foo3/2016-04-02-2110/delta
@@ -0,0 +1 @@
+4.744116
diff --git a/lib/ctt/test/fixtures/.ctt/spam-eggs/2016-04-07-1229/comment b/lib/ctt/test/fixtures/.ctt/spam-eggs/2016-04-07-1229/comment
new file mode 100644
index 0000000..36c95ea
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/spam-eggs/2016-04-07-1229/comment
@@ -0,0 +1 @@
+spam-eggs
diff --git a/lib/ctt/test/fixtures/.ctt/spam-eggs/2016-04-07-1229/delta b/lib/ctt/test/fixtures/.ctt/spam-eggs/2016-04-07-1229/delta
new file mode 100644
index 0000000..4b20c52
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/spam-eggs/2016-04-07-1229/delta
@@ -0,0 +1 @@
+3.307185
diff --git a/lib/ctt/test/fixtures/.ctt/test-1/2016-04-02-2109/comment b/lib/ctt/test/fixtures/.ctt/test-1/2016-04-02-2109/comment
new file mode 100644
index 0000000..8e2baef
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/test-1/2016-04-02-2109/comment
@@ -0,0 +1 @@
+test-1
diff --git a/lib/ctt/test/fixtures/.ctt/test-1/2016-04-02-2109/delta b/lib/ctt/test/fixtures/.ctt/test-1/2016-04-02-2109/delta
new file mode 100644
index 0000000..bbec04c
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/test-1/2016-04-02-2109/delta
@@ -0,0 +1 @@
+2.972467
diff --git a/lib/ctt/test/fixtures/.ctt/test-2/2016-04-02-2109/comment b/lib/ctt/test/fixtures/.ctt/test-2/2016-04-02-2109/comment
new file mode 100644
index 0000000..38c98d9
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/test-2/2016-04-02-2109/comment
@@ -0,0 +1 @@
+test-2
diff --git a/lib/ctt/test/fixtures/.ctt/test-2/2016-04-02-2109/delta b/lib/ctt/test/fixtures/.ctt/test-2/2016-04-02-2109/delta
new file mode 100644
index 0000000..d1bf127
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/test-2/2016-04-02-2109/delta
@@ -0,0 +1 @@
+2.558247
diff --git a/lib/ctt/test/fixtures/.ctt/test-3/2016-04-02-2109/comment b/lib/ctt/test/fixtures/.ctt/test-3/2016-04-02-2109/comment
new file mode 100644
index 0000000..1be6ab6
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/test-3/2016-04-02-2109/comment
@@ -0,0 +1 @@
+test-3
diff --git a/lib/ctt/test/fixtures/.ctt/test-3/2016-04-02-2109/delta b/lib/ctt/test/fixtures/.ctt/test-3/2016-04-02-2109/delta
new file mode 100644
index 0000000..6a2731f
--- /dev/null
+++ b/lib/ctt/test/fixtures/.ctt/test-3/2016-04-02-2109/delta
@@ -0,0 +1 @@
+1.821598
diff --git a/lib/ctt/test/test_listprojects.py b/lib/ctt/test/test_listprojects.py
new file mode 100755
index 0000000..17ddfe7
--- /dev/null
+++ b/lib/ctt/test/test_listprojects.py
@@ -0,0 +1,38 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+#
+# 2016 Darko Poljak (darko.poljak at gmail.com)
+#
+# This file is part of ctt.
+#
+# ctt is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# ctt is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with ctt. If not, see <http://www.gnu.org/licenses/>.
+#
+#
+
+import unittest
+import ctt
+import ctt.listprojects as cttls
+import ctt.test
+
+class ListProjectsTestCase(ctt.test.CttTestCase):
+
+    def test_list_projects(self):
+        projects = cttls.ListProjects.list_projects()
+        expected_projects = [ 'foo1', 'foo2', 'foo3', 'spam-eggs',
+                'test-1', 'test-2', 'test-3', ]
+        gotten_projects = sorted(projects)
+        self.assertEqual(gotten_projects, expected_projects)
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/lib/ctt/test/test_report.py b/lib/ctt/test/test_report.py
new file mode 100755
index 0000000..c715a1d
--- /dev/null
+++ b/lib/ctt/test/test_report.py
@@ -0,0 +1,225 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+#
+# 2016 Darko Poljak (darko.poljak at gmail.com)
+#
+# This file is part of ctt.
+#
+# ctt is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# ctt is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with ctt. If not, see <http://www.gnu.org/licenses/>.
+#
+#
+
+import unittest
+import ctt
+import ctt.test
+import ctt.report as report
+import sys
+from io import StringIO
+import datetime
+import collections
+
+
+class ReportTestCase(ctt.test.CttTestCase):
+    def setUp(self):
+        super(ReportTestCase, self).setUp()
+        self.sys_stdout = sys.stdout
+        out = StringIO()
+        sys.stdout = out
+        self.maxDiff = None
+
+    def _get_output(self):
+        sys.stdout.flush()
+        output = sys.stdout.getvalue().strip()
+        return output
+
+    def tearDown(self):
+        sys.stdout = self.sys_stdout
+        super(ReportTestCase, self).tearDown()
+
+    def test_print_report_time_entries(self):
+        report_data = {
+            '2016-04-07-0826': [
+                {
+                'start_datetime': '2016-04-07-0826',
+                'end_datetime': '2016-04-07-2359',
+                'comment': 'foo1',
+                'delta': '6',
+                'delta_seconds': '6',
+                'delta_minutes': '0',
+                },
+            ],
+        }
+        report.Report.print_report_time_entries(report_data, ctt.REPORTFORMAT,
+                False)
+        output = self._get_output()
+        expected_output = "2016-04-07-0826 (6): foo1"
+        self.assertEqual(output, expected_output)
+
+    def test_print_report_time_entries_summary(self):
+        report_data = {
+            '2016-04-07-0826': [
+                {
+                'start_datetime': '2016-04-07-0826',
+                'end_datetime': '2016-04-07-2359',
+                'comment': 'foo1',
+                'delta': '6',
+                'delta_seconds': '6',
+                'delta_minutes': '0',
+                },
+            ],
+            '2016-04-07-0926': [
+                {
+                'start_datetime': '2016-04-07-0926',
+                'end_datetime': '2016-04-07-2359',
+                'comment': 'foo12',
+                'delta': '10',
+                'delta_seconds': '10',
+                'delta_minutes': '0',
+                },
+            ],
+        }
+        report.Report.print_report_time_entries(report_data, ctt.REPORTFORMAT,
+                True)
+        output = self._get_output()
+        expected_output = ("2016-04-07-0826 (6): foo1\n"
+                "2016-04-07-0926 (10): foo12")
+        self.assertEqual(output, expected_output)
+
+    def test_print_reports(self):
+        reports = collections.OrderedDict()
+        for project in ('foo1', 'foo2'):
+            rep = report.Report(project, ('2016-04-07',), ('2016-04-08',), 
+                    ctt.REPORTFORMAT, None, None)
+            report_data = rep.report()
+            reports[project] = (rep, report_data)
+        expected_output = (
+            "Report for foo1 between 2016-04-07 00:00:00 and 2016-04-08 23:59:59\n"
+            "2016-04-07-0826 (0:00:06): foo1\n"
+            "2016-04-08-1200 (1:23:20): foo1 12\n"
+            "Report for foo2 between 2016-04-07 00:00:00 and 2016-04-08 23:59:59\n"
+            "2016-04-07-0810 (0:00:10): foo2"
+        )
+        rep.print_reports(reports, ctt.REPORTFORMAT, summary=False)
+        output = self._get_output()
+        self.assertEqual(output, expected_output)
+
+    def test_print_reports_summary(self):
+        reports = collections.OrderedDict()
+        for project in ('foo1', 'foo2'):
+            rep = report.Report(project, ('2016-04-07',), ('2016-04-08',), 
+                    ctt.REPORTFORMAT, None, None)
+            report_data = rep.report()
+            reports[project] = (rep, report_data)
+        expected_output = (
+            "2016-04-07-0810 (0:00:10): foo2\n"
+            "2016-04-07-0826 (0:00:06): foo1\n"
+            "2016-04-08-1200 (1:23:20): foo1 12"
+        )
+        rep.print_reports(reports, ctt.REPORTFORMAT, summary=True)
+        output = self._get_output()
+        self.assertEqual(output, expected_output)
+
+
+    def test__init_date(self):
+        rep = report.Report('foo1', ('2016-04-07',), ('2016-04-07',), 
+                ctt.REPORTFORMAT, None, None)
+        expected_start_date = datetime.datetime(2016, 4, 7)
+        expected_end_date = datetime.datetime(2016, 4, 7, 23, 59, 59)
+        self.assertEqual(rep.start_date, expected_start_date)
+        self.assertEqual(rep.end_date, expected_end_date)
+
+    @unittest.expectedFailure
+    def test__init_date_fail(self):
+        rep = report.Report('foo1', ('2016-04-08',), ('2016-04-07',), 
+                ctt.REPORTFORMAT, None, None)
+
+    def test__init_date_defaults(self):
+        rep = report.Report('foo1', None, None,
+                ctt.REPORTFORMAT, None, None)
+        now = datetime.datetime.now()
+        expected_start_date = now.replace(day=1, hour=0, minute=0, second=0,
+                microsecond=0)
+        next_month = expected_start_date.replace(day=28) + datetime.timedelta(days=4)
+        first_day_next_month = next_month.replace(day=1)
+        expected_end_date = first_day_next_month - datetime.timedelta(seconds=1)
+        self.assertEqual(rep.start_date, expected_start_date)
+        self.assertEqual(rep.end_date, expected_end_date)
+
+    @unittest.expectedFailure
+    def test__init_report_db_fail(self):
+        rep = report.Report('unexisting', ('2016-04-07',), ('2016-04-07',), 
+                ctt.REPORTFORMAT, None, None)
+
+    def test__init_report_db(self):
+        rep = report.Report('foo1', ('2016-04-07',), ('2016-04-07',), 
+                ctt.REPORTFORMAT, None, None)
+        expected_db =  {
+                '2016-04-07-0826': {
+                    'comment': 'foo1',
+                    'delta': '6.248274'
+                },
+        }
+        self.assertEqual(rep._report_db, expected_db)
+
+    def test_header(self):
+        rep = report.Report('foo1', ('2016-04-07',), ('2016-04-07',), 
+                ctt.REPORTFORMAT, None, None)
+        rep.header()
+        output = self._get_output()
+        self.assertEqual(output, ("Report for foo1 between 2016-04-07 00:00:00"
+            " and 2016-04-07 23:59:59"))
+
+    def test_summary(self):
+        report.Report.summary(10)
+        output = self._get_output()
+        self.assertEqual(output, "Total time tracked: 0h 0m 10s.")
+
+    def test_total_time(self):
+        rep = report.Report('foo1', ('2016-04-07',), ('2016-04-07',), 
+                ctt.REPORTFORMAT, None, None)
+        total_time = rep.total_time
+        expected_total_time =  6.248274
+        self.assertEqual(total_time, expected_total_time)
+
+    def test_report(self):
+        rep = report.Report('foo1', ('2016-04-07',), ('2016-04-08',), 
+                ctt.REPORTFORMAT, None, None)
+        expected_entries = {
+                '2016-04-07-0826': [
+                    {
+                    'start_datetime': '2016-04-07-0826',
+                    'end_datetime': '2016-04-07-0826',
+                    'comment': 'foo1',
+                    'delta': datetime.timedelta(seconds=6),
+                    'delta_seconds': 6,
+                    'delta_minutes': 0,
+                    },
+                ],
+                '2016-04-08-1200': [
+                    {
+                    'start_datetime': '2016-04-08-1200',
+                    'end_datetime': '2016-04-08-1323',
+                    'comment': 'foo1 12',
+                    'delta': datetime.timedelta(seconds=5000),
+                    'delta_seconds': 5000,
+                    'delta_minutes': 83,
+                    },
+                ],
+        }
+        entries = rep.report()
+        self.assertEqual(entries, expected_entries)
+
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/lib/ctt/test/test_tracker.py b/lib/ctt/test/test_tracker.py
new file mode 100755
index 0000000..c7c6caf
--- /dev/null
+++ b/lib/ctt/test/test_tracker.py
@@ -0,0 +1,145 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+#
+# 2016 Darko Poljak (darko.poljak at gmail.com)
+#
+# This file is part of ctt.
+#
+# ctt is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# ctt is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with ctt. If not, see <http://www.gnu.org/licenses/>.
+#
+#
+
+import unittest
+import ctt
+import ctt.test
+import ctt.tracker as tr
+import os
+import datetime
+import shutil
+
+class TrackerTestCase(ctt.test.CttTestCase):
+
+    def setUp(self):
+        super(TrackerTestCase, self).setUp()
+        self.rm_dirs = []
+
+    def tearDown(self):
+        for d in self.rm_dirs:
+            if os.path.exists(d):
+                shutil.rmtree(d)
+        super(TrackerTestCase, self).tearDown()
+
+    def test___init__(self):
+        project = 'foo1'
+        expected_project_dir = os.path.join(ctt.test.fixtures_dir,
+                os.path.join('.ctt', project))
+        tracker = tr.Tracker(project)
+        self.assertEqual(tracker.project, project)
+        self.assertEqual(tracker.project_dir, expected_project_dir)
+        self.assertIsNone(tracker.start_datetime)
+        self.assertIsNone(tracker.end_datetime)
+        self.assertIsNone(tracker.comment)
+        self.assertFalse(tracker._tracked_time)
+
+        tracker = tr.Tracker(project, start_datetime=('2016-04-09-0900',))
+        self.assertEqual(tracker.start_datetime,
+                datetime.datetime(2016, 4, 9, 9, 0))
+        self.assertIsNone(tracker.end_datetime)
+        self.assertFalse(tracker._tracked_time)
+
+        tracker = tr.Tracker(project, start_datetime=('2016-04-04-0900',),
+                end_datetime=('2016-04-09-2000',))
+        self.assertEqual(tracker.start_datetime,
+                datetime.datetime(2016, 4, 4, 9, 0))
+        self.assertEqual(tracker.end_datetime,
+                datetime.datetime(2016, 4, 9, 20, 0))
+        self.assertTrue(tracker._tracked_time)
+
+    @unittest.expectedFailure
+    def test__init__fail(self):
+        project = 'foo1'
+        tracker = tr.Tracker(project, start_datetime=('2016-04-090900',))
+
+    def test_delta(self):
+        project = 'foo1'
+        start_dt = datetime.datetime(2016, 4, 4, 9, 0)
+        end_dt = datetime.datetime(2016, 4, 9, 20, 0)
+        tracker = tr.Tracker(project, start_datetime=('2016-04-04-0900',),
+                end_datetime=('2016-04-09-2000',))
+        expected_delta = end_dt - start_dt
+        tracker._tracked_time = True
+        delta = tracker.delta(True)
+        self.assertEqual(delta, expected_delta.total_seconds())
+        delta = tracker.delta(False)
+        self.assertEqual(delta, expected_delta)
+        tracker._tracked_time = False
+        delta = tracker.delta(True)
+        self.assertEqual(delta, 0)
+        delta = tracker.delta(False)
+        self.assertEqual(delta, datetime.timedelta())
+
+    def test_write_time(self):
+        project = 'foo1'
+        start_dt = '2016-04-09-1730'
+        tracker = tr.Tracker(project, start_datetime=(start_dt,),
+                comment=True)
+        end_dt = datetime.datetime(2016, 4, 9, hour=17, minute=45)
+        expected_delta = str(15 * 60) + '.0\n'  # seconds
+        tracker.end_datetime = end_dt
+        tracker._tracked_time = True
+        expected_comment = "test"
+        tracker.comment = expected_comment
+        expected_comment += "\n"
+        timedir = os.path.join(ctt.test.fixtures_dir, '.ctt', project,
+            '2016-04-09-1730')
+        self.rm_dirs.append(timedir)
+        if os.path.exists(timedir):
+            shutil.rmtree(timedir)
+        tracker.write_time()
+        timefile = os.path.join(timedir, ctt.FILE_DELTA)
+        self.assertTrue(os.path.exists(timefile))
+        with open(timefile, "r") as f:
+            delta = f.read()
+        self.assertEqual(delta, expected_delta)
+        commentfile = os.path.join(timedir, ctt.FILE_COMMENT)
+        self.assertTrue(os.path.exists(commentfile))
+        with open(commentfile, "r") as f:
+            comment = f.read()
+        self.assertEqual(comment, expected_comment)
+        print("timedir: ", timedir)
+
+    @unittest.expectedFailure
+    def test_write_time_fail(self):
+        project = 'foo1'
+        start_dt = '2016-04-09-1730'
+        tracker = tr.Tracker(project, start_datetime=(start_dt,),
+                comment=True)
+        end_dt = datetime.datetime(2016, 4, 9, hour=17, minute=45)
+        expected_delta = 15 * 60  # seconds
+        tracker.end_datetime = end_dt
+        tracker._tracked_time = True
+        expected_comment = "test"
+        tracker.comment = expected_comment
+        timedir = os.path.join(ctt.test.fixtures_dir, '.ctt', project,
+            '2016-04-09-1730')
+        self.rm_dirs.append(timedir)
+        if os.path.exists(timedir):
+            shutil.rmtree(timedir)
+        os.makedirs(timedir, mode=0o700)
+        tracker.write_time()
+        print("timedir: ", timedir)
+
+
+if __name__ == '__main__':
+    unittest.main()