Use datetime.timedelta for extract_duration_en.

This is in support of issues-1959.

mycroft/util/lang/parse_en.py

@@ -14,7 +14,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
-from datetime import datetime
+from datetime import datetime, timedelta
 
 from dateutil.relativedelta import relativedelta
 
@@ -656,29 +656,30 @@ def extract_duration_en(text):
     if not text:
         return None
 
-    time_unit_to_seconds_map = {
-        'second': 1,
-        'minute': 60,
-        'hour': 3600,
-        'day': 86400,
-        'week': 604800
+    time_units = {
+        'microseconds': None,
+        'milliseconds': None,
+        'seconds': None,
+        'minutes': None,
+        'hours': None,
+        'days': None,
+        'weeks': None
     }
 
     pattern = r"(?P<value>\d+(?:\.?\d+)?)\s+{unit}s?"
     text = _convert_words_to_numbers(text)
 
-    pieces = []
-    for unit, value in time_unit_to_seconds_map.items():
-        unit_pattern = pattern.format(unit=unit)
+    for unit in time_units:
+        unit_pattern = pattern.format(unit=unit[:-1])  # remove 's' from unit
         matches = re.findall(unit_pattern, text)
-        matches = map(lambda s: float(s) * value, matches)
-        pieces += matches
+        value = sum(map(float, matches))
+        time_units[unit] = value
         text = re.sub(unit_pattern, '', text)
 
     text = text.strip()
-    duration = sum(pieces)
+    duration = timedelta(**time_units) if any(time_units.values()) else None
 
-    return (duration, text) if pieces else (None, text)
+    return (duration, text)
 
 
 def extract_datetime_en(string, dateNow, default_time):

test/unittests/util/test_parse.py

@@ -15,7 +15,7 @@
 # limitations under the License.
 #
 import unittest
-from datetime import datetime
+from datetime import datetime, timedelta
 
 from mycroft.util.parse import extract_datetime
 from mycroft.util.parse import extract_duration
@@ -142,28 +142,39 @@ class TestNormalize(unittest.TestCase):
         self.assertEqual(extract_number("a couple thousand beers"), 2000)
 
     def test_extract_duration_en(self):
-        self.assertEqual(extract_duration("10 seconds"), (10.0, ""))
-        self.assertEqual(extract_duration("5 minutes"), (300.0, ""))
-        self.assertEqual(extract_duration("2 hours"), (7200.0, ""))
-        self.assertEqual(extract_duration("3 days"), (259200.0, ""))
-        self.assertEqual(extract_duration("25 weeks"), (15120000.0, ""))
-        self.assertEqual(extract_duration("seven hours"), (25200.0, ""))
-        self.assertEqual(extract_duration("7.5 seconds"), (7.5, ""))
+        self.assertEqual(extract_duration("10 seconds"),
+                         (timedelta(seconds=10.0), ""))
+        self.assertEqual(extract_duration("5 minutes"),
+                         (timedelta(minutes=5), ""))
+        self.assertEqual(extract_duration("2 hours"),
+                         (timedelta(hours=2), ""))
+        self.assertEqual(extract_duration("3 days"),
+                         (timedelta(days=3), ""))
+        self.assertEqual(extract_duration("25 weeks"),
+                         (timedelta(weeks=25), ""))
+        self.assertEqual(extract_duration("seven hours"),
+                         (timedelta(hours=7), ""))
+        self.assertEqual(extract_duration("7.5 seconds"),
+                         (timedelta(seconds=7.5), ""))
         self.assertEqual(extract_duration("eight and a half days thirty"
-                                          " nine seconds"), (734439.0, ""))
+                         " nine seconds"),
+                         (timedelta(days=8.5, seconds=39), ""))
         self.assertEqual(extract_duration("Set a timer for 30 minutes"),
-                         (1800.0, "set a timer for"))
+                         (timedelta(minutes=30), "set a timer for"))
         self.assertEqual(extract_duration("Four and a half minutes until"
-                                          " sunset"), (270.0, "until sunset"))
+                         " sunset"),
+                         (timedelta(minutes=4.5), "until sunset"))
         self.assertEqual(extract_duration("Nineteen minutes past the hour"),
-                         (1140.0, "past the hour"))
+                         (timedelta(minutes=19), "past the hour"))
         self.assertEqual(extract_duration("wake me up in three weeks, four"
                                           " hundred ninety seven days, and"
                                           " three hundred 91.6 seconds"),
-                         (44755591.6, "wake me up in , , and"))
+                         (timedelta(weeks=3, days=497, seconds=391.6),
+                             "wake me up in , , and"))
         self.assertEqual(extract_duration("The movie is one hour, fifty seven"
                                           " and a half minutes long"),
-                         (7050.0, "the movie is ,  long"))
+                         (timedelta(hours=1, minutes=57.5),
+                             "the movie is ,  long"))
 
     def test_extractdatetime_en(self):
         def extractWithFormat(text):