Fixing errounous rounding in Duration. Fix docstrings

src/compas_fab/robots/time_.py

@@ -10,16 +10,38 @@
 
 
 class Duration(Data):
-    """Duration consists of two values: seconds (float) and nanoseconds (int).
-    The total number of seconds is the sum of these values.
-    The decimal portion of the secs variable is converted to an integer and added to nsecs.
+    """Duration is used to accurately describe the passage of time.
+    It consists of seconds and nanoseconds, the total duration is the sum of the two values.
 
-    Attributes
+    Parameters
     ----------
-    secs: float
-        Float representing number of seconds.
+    secs: int or float
+        Integer representing number of seconds.
+        If a float is passed, the integer portion is assigned to secs and
+        the decimal portion of the secs variable is converted and added to nsecs.
     nsecs: int
         Integer representing number of nanoseconds.
+
+    Attributes
+    ----------
+    seconds: float, read-only
+        Returns the total duration as floating-point seconds.
+
+    Examples
+    --------
+    >>> d = Duration(2, 5e8)
+    >>> d.seconds
+    2.5
+    >>> d = Duration(2.6, 0)
+    >>> d.seconds
+    2.6
+    >>> d = Duration(2.6, 5e8)
+    >>> d.secs
+    3
+    >>> d.nsecs
+    100000000
+    >>> d.seconds
+    3.1
     """
 
     def __init__(self, secs, nsecs):
@@ -30,6 +52,11 @@ def __init__(self, secs, nsecs):
         self.secs = int(quotient)
         self.nsecs = int(remainder * sec_to_nano_factor) + int(nsecs)
 
+        # If nsecs is greater than 1 second, add the remainder back to secs
+        if self.nsecs >= sec_to_nano_factor:
+            self.secs += 1
+            self.nsecs -= int(sec_to_nano_factor)
+
     def __str__(self):
         return "Duration({!r}, {!r})".format(self.secs, self.nsecs)
 
@@ -47,13 +74,6 @@ def __ne__(self, other):
 
     @property
     def seconds(self):
-        """Returns the duration as floating-point seconds.
-
-        Returns
-        -------
-        float
-            Floating-point seconds
-        """
         return self.secs + 1e-9 * self.nsecs
 
     @property

tests/robots/test_duration.py

@@ -13,6 +13,8 @@ def test_ctor_takes_sec_as_float():
 
 def test_sec_remainder_add_to_nsec():
     d = Duration(2.6, 5e8)
+    assert d.secs == 3
+    assert d.nsecs == 1e8
     assert d.seconds == 3.1