Validate input of Time ctor (#90)

Author: gonzalocasas

CHANGELOG.rst

@@ -18,6 +18,8 @@ Unreleased
 
 **Fixed**
 
+* Ensure input of ``Time`` is always two integers.
+
 **Deprecated**
 
 **Removed**

src/roslibpy/core.py

@@ -2,6 +2,7 @@
 
 import json
 import logging
+from multiprocessing.sharedctypes import Value
 import time
 
 # Python 2/3 compatibility import list
@@ -12,12 +13,16 @@
 
 LOGGER = logging.getLogger('roslibpy')
 
-__all__ = ['Message',
-           'ServiceRequest',
-           'ServiceResponse',
-           'Topic',
-           'Service',
-           'Param']
+__all__ = [
+    'Header',
+    'Message',
+    'Param',
+    'Service',
+    'ServiceRequest',
+    'ServiceResponse',
+    'Time',
+    'Topic'
+]
 
 
 class Message(UserDict):
@@ -44,8 +49,15 @@ class Time(UserDict):
     """Represents ROS time with two integers: seconds since epoch and nanoseconds since seconds."""
     def __init__(self, secs, nsecs):
         self.data = {}
-        self.data['secs'] = secs
-        self.data['nsecs'] = nsecs
+        self.data['secs'] = self._ensure_int(secs)
+        self.data['nsecs'] = self._ensure_int(nsecs)
+
+    def _ensure_int(self, n):
+        if isinstance(n, int):
+            return n
+        if isinstance(n, float) and n.is_integer():
+            return int(n)
+        raise ValueError('argument must be an integer')
 
     @property
     def secs(self):

tests/test_core.py

@@ -1,3 +1,5 @@
+import pytest
+
 from roslibpy import Header
 from roslibpy import Time
 
@@ -37,3 +39,22 @@ def test_header_ctor_supports_dict():
     assert header['stamp']['secs'] == 1610122759
     assert header['stamp']['secs'] == header['stamp'].secs
     assert header['stamp'].to_sec() == REF_FLOAT_SECS_TIME
+
+
+def test_time_accepts_only_ints():
+    with pytest.raises(ValueError):
+        Time(1.3, 1.0)
+    with pytest.raises(ValueError):
+        Time(100.0, 3.1)
+
+    t = Time(110.0, 0.0)
+    assert t.secs == 110
+    assert t.nsecs == 0
+
+
+def test_time_properties_are_readonly():
+    t = Time.now()
+    with pytest.raises(AttributeError):
+        t.secs = 10
+    with pytest.raises(AttributeError):
+        t.nsecs = 10