test: create test_plotdesc

tests/test_plotdesc.py

@@ -0,0 +1,32 @@
+from grum.plotdesc import PlotDescription
+import pytest
+
+@pytest.mark.parametrize(
+    "plot_name, plot_title, plot_xlabel, plot_ylabel, xs,ys", [('plot_name', 
+    'plot_title', 
+    'plot_xlabel', 
+    'plot_ylabel', 
+    [1, 2], 
+    [3, 4]), 
+    ('plot_name', 
+    None, 
+    None, 
+    None, 
+    [], 
+    [])]
+)
+def test_plot_derscription_init(plot_name, plot_title, plot_xlabel, plot_ylabel, xs, ys):
+
+    if plot_title:
+        pd = PlotDescription(plot_name, plot_title,
+                         plot_xlabel, plot_ylabel, xs, ys)
+    else: 
+        pd = PlotDescription(plot_name)
+    
+    assert pd.name == plot_name
+    assert pd.title == plot_title
+    assert pd.xlabel == plot_xlabel
+    assert pd.ylabel == plot_ylabel
+    assert pd.xs == xs
+    assert pd.ys == ys
+