Fix issue #238: wrong position swap code. (#240)

* Fix issue #238: wrong position swap code.

* Fix test for travisCI: use other supported timezone

Author: NateScarlet

.gitignore

@@ -31,3 +31,7 @@ profile.html
 /wheelhouse
 /docs/site/*
 pyproject.lock
+
+# editor
+
+.vscode

pendulum/_extensions/helpers.py

@@ -282,10 +282,6 @@ def precise_diff(d1, d2):
             hour_diff += 24
             d_diff -= 1
 
-    if d1 > d2:
-        d1, d2 = d2, d1
-        sign = -1
-
     y_diff = d2.year - d1.year
     m_diff = d2.month - d1.month
     d_diff += d2.day - d1.day

tests/test_helpers.py

@@ -115,6 +115,14 @@ def test_precise_diff_timezone():
         days=1, hours=5
     )
 
+    # Issue238
+    dt1 = timezone('UTC').datetime(2018, 6, 20, 1, 30)
+    dt2 = timezone('Europe/Paris').datetime(2018, 6, 20, 3, 40) # UTC+2
+    diff = precise_diff(dt1, dt2)
+    assert_diff(
+        diff,
+        minutes=10
+    )
 
 def test_week_day():
     assert 5 == week_day(2017, 6, 2)