Fix calling plot with keyword arguments

src/py4vasp/_third_party/graph/plot.py

@@ -37,12 +37,19 @@ def plot(*args, **kwargs):
 
 
 def _parse_series(*args, **kwargs):
+    if series := _parse_multiple_series(*args, **kwargs):
+        return series
+    else:
+        return _parse_single_series(*args, **kwargs)
+
+
+def _parse_multiple_series(*args, **kwargs):
     try:
         return [Series(*arg) for arg in args]
     except TypeError:
-        # A TypeError is raised, if plot(x, y) is called instead of plot((x, y)).
-        # Because we creating the Series may raise another error, we leave the
-        # exception handling first to avoid reraising the TypeError.
-        pass
+        return []
+
+
+def _parse_single_series(*args, **kwargs):
     for_series = {key: val for key, val in kwargs.items() if key in Series._fields}
     return Series(*args, **for_series)

tests/third_party/graph/test_plot.py

@@ -19,6 +19,8 @@ def test_plot():
     assert plot((x1, y1)) == Graph([series0])
     assert plot((x1, y1), (x2, y2, "label2")) == Graph([series0, series2])
     assert plot((x1, y1), xlabel="xaxis") == Graph([series0], xlabel="xaxis")
+    assert plot(x1, y=y1) == Graph(series0)
+    assert plot(x=x1, y=y1) == Graph(series0)
 
 
 def test_plot_small_dataset():