Fix #9: Add time to previous task for status cmd

This commit updates the `status` command to include the time spent on
the previous command. It also adds some unit tests for the old
`get_previous_task()` and the new `get_previous_task_and_time()`
functions.

ttrack/bin/ttrack

@@ -75,8 +75,7 @@ def format_duration(secs):
 
 
 def format_duration_since_datetime(dt):
-    now = datetime.datetime.now()
-    delta = now - dt
+    delta = datetime.datetime.now() - dt
     return format_duration(delta.days * 86400 + delta.seconds)
 
 
@@ -659,11 +658,12 @@ class CommandHandler(cmd.Cmd):
         """
 
         try:
-            prev = self.db.get_previous_task()
+            prev = self.db.get_previous_task_and_time()
             if prev is None:
                 print "No previous task."
             else:
-                print "Previous task: %s" % (prev,)
+                dur_str = format_duration(prev[1])
+                print "Previous task: %s (for %s)" % (prev[0], dur_str)
             task = self.db.get_current_task()
             if task is None:
                 print "No current task."

ttrack/lib/tracklib.py

@@ -444,20 +444,21 @@ def _get_current_task_with_id(self):
             return row
 
 
-    def _get_previous_task_with_id(self):
+    def _get_previous_task_and_time_with_id(self):
         """Return tuple of (log entry id, task name) or None."""
 
         task = self._get_current_task_with_id()
         cur = self.conn.cursor()
         if task is None:
-            cur.execute("SELECT L.id, T.name FROM tasklog AS L"
+            cur.execute("SELECT L.id, T.name, L.start, L.end FROM tasklog AS L"
                         " INNER JOIN tasks AS T ON L.task=T.id"
+                        " WHERE L.end is NOT NULL"
                         " ORDER BY L.end DESC LIMIT 1")
         else:
             cur_task_id = self.tasks.get_id(task[1])
-            cur.execute("SELECT L.id, T.name FROM tasklog AS L"
+            cur.execute("SELECT L.id, T.name, L.start, L.end FROM tasklog AS L"
                         " INNER JOIN tasks AS T ON L.task=T.id"
-                        " WHERE end IS NOT NULL AND L.task!=?"
+                        " WHERE L.end IS NOT NULL AND L.task!=?"
                         " ORDER BY L.end DESC LIMIT 1", (cur_task_id,))
         row = cur.fetchone()
         if row is None:
@@ -479,11 +480,18 @@ def get_current_task(self):
     def get_previous_task(self):
         """Returns the name of the highest completed task."""
 
-        task = self._get_previous_task_with_id()
-        if task is None:
+        task_and_time = self.get_previous_task_and_time()
+        return task_and_time[0] if task_and_time is not None else None
+
+
+    def get_previous_task_and_time(self):
+        """As get_previous_task() but returns a tuple: (task, start, end)."""
+
+        task_and_time = self._get_previous_task_and_time_with_id()
+        if task_and_time is None:
             return None
         else:
-            return task[1]
+            return (task_and_time[1], task_and_time[3] - task_and_time[2])
 
 
     def get_last_created_task(self):

ttrack/test/test_tracklib.py

@@ -446,6 +446,17 @@ def test_current_task(self):
         self.assertEqual(self.db.get_current_task(), None)
 
 
+    def test_previous_task(self):
+        self.db.tasks.add("task1")
+        self.db.tasks.add("task2")
+        self.db.start_task("task1", datetime.datetime(2013, 3, 26, 10, 0))
+        self.db.stop_task(datetime.datetime(2013, 3, 26, 10, 30))
+        self.db.start_task("task2", datetime.datetime(2013, 3, 26, 11, 0))
+        self.assertEqual(self.db.get_current_task(), "task2")
+        self.assertEqual(self.db.get_previous_task(), "task1")
+        self.assertEqual(self.db.get_previous_task_and_time(), ("task1", 1800))
+
+
     def test_add_task_tags(self):
         self.db.tasks.add("task1")
         self.db.tasks.add("task2")