Fix update clocks (#151)

* fix update clocks: 1 coord given for master clock

* update + add regression test

* update release notes

Author: benbovy

doc/whats_new.rst

@@ -31,6 +31,8 @@ Bug fixes
   ``_FillValue`` attribute (:issue:`148`).
 - Ensure that classes given in a Model are all process-decorated, even those
   which inherit from process-decorated classes (:issue:`149`).
+- Fix :func:`~xarray.Dataset.xsimlab.update_clocks` when only the master clock is
+  updated implicitly (:issue:`151`).
 
 v0.4.1 (17 April 2020)
 ----------------------

xsimlab/tests/test_xr_accessor.py

@@ -218,42 +218,37 @@ def test_set_input_vars(self, model, in_dataset):
 
     def test_update_clocks(self, model):
         ds = xr.Dataset()
-        with pytest.raises(ValueError) as excinfo:
+        with pytest.raises(ValueError, match="Cannot determine which clock.*"):
             ds.xsimlab.update_clocks(model=model, clocks={})
-        assert "Cannot determine which clock" in str(excinfo.value)
 
         ds = xr.Dataset()
-        with pytest.raises(ValueError) as excinfo:
+        with pytest.raises(ValueError, match="Cannot determine which clock.*"):
             ds.xsimlab.update_clocks(
                 model=model, clocks={"clock": [0, 1, 2], "out": [0, 2]}
             )
-        assert "Cannot determine which clock" in str(excinfo.value)
 
         ds = xr.Dataset()
-        with pytest.raises(KeyError) as excinfo:
+        with pytest.raises(KeyError, match="Master clock dimension name.*"):
             ds.xsimlab.update_clocks(
                 model=model,
                 clocks={"clock": [0, 1, 2]},
                 master_clock="non_existing_clock_dim",
             )
-        assert "Master clock dimension name" in str(excinfo.value)
 
         ds = xr.Dataset()
-        with pytest.raises(ValueError) as excinfo:
+        with pytest.raises(ValueError, match="Invalid dimension.*"):
             ds.xsimlab.update_clocks(
                 model=model,
                 clocks={"clock": ("x", [0, 1, 2])},
             )
-        assert "Invalid dimension" in str(excinfo.value)
 
         ds = xr.Dataset()
-        with pytest.raises(ValueError) as excinfo:
+        with pytest.raises(ValueError, match=".*not synchronized.*"):
             ds.xsimlab.update_clocks(
                 model=model,
                 clocks={"clock": [0, 1, 2], "out": [0, 0.5, 2]},
                 master_clock="clock",
             )
-        assert "not synchronized" in str(excinfo.value)
 
         ds = xr.Dataset()
         ds = ds.xsimlab.update_clocks(model=model, clocks={"clock": [0, 1, 2]})
@@ -285,6 +280,10 @@ def test_update_clocks(self, model):
         new_ds = ds.xsimlab.update_clocks(model=model, clocks={"out2": [0, 2]})
         assert new_ds.xsimlab.master_clock_dim == "clock"
 
+        new_ds = ds.xsimlab.update_clocks(model=model, clocks={"clock": [0, 2, 4]})
+        assert new_ds.xsimlab.master_clock_dim == "clock"
+        np.testing.assert_array_equal(new_ds.clock.values, [0, 2, 4])
+
     def test_update_vars(self, model, in_dataset):
         ds = in_dataset.xsimlab.update_vars(
             model=model,

xsimlab/xr_accessor.py

@@ -509,7 +509,7 @@ def update_clocks(self, model=None, clocks=None, master_clock=None):
             ):
                 master_clock_dict = {"dim": list(clocks.keys())[0]}
             else:
-                master_clock_dict = {}
+                master_clock_dict = {"dim": self.master_clock_dim}
 
         else:
             master_clock_dict = master_clock