Simpler code path

Author: scottshambaugh

labellines/core.py

@@ -185,14 +185,13 @@ def labelLines(
             xvals = (xvals[0] + shrinkage, xvals[1] - shrinkage)
 
     if isinstance(xvals, tuple) and len(xvals) == 2:
-        xmin, xmax = xvals
-        xscale = ax.get_xscale()
-
         # Convert datetime objects to numeric values for linspace/geomspace
-        x_is_datetime = isinstance(xmin, datetime) or isinstance(xmax, datetime)
+        x_is_datetime = isinstance(xvals[0], datetime)
         if x_is_datetime:
-            xmin = plt.matplotlib.dates.date2num(xmin)
-            xmax = plt.matplotlib.dates.date2num(xmax)
+            xvals = plt.matplotlib.dates.date2num(xvals)
+
+        xmin, xmax = xvals
+        xscale = ax.get_xscale()
 
         if xscale == "log":
             xvals = np.geomspace(xmin, xmax, len(all_lines) + 2)[1:-1]