From 191ef1bbb7b3d85c6e76412a2175744068224138 Mon Sep 17 00:00:00 2001
From: Thomas Robitaille <thomas.robitaille@gmail.com>
Date: Fri, 2 Dec 2016 12:44:48 +0000
Subject: [PATCH] Minor fixes to plot_coord function and tests

---
 wcsaxes/core.py              | 11 +++++------
 wcsaxes/tests/test_images.py |  8 ++++----
 2 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/wcsaxes/core.py b/wcsaxes/core.py
index 4d3c07a..a39de2e 100644
--- a/wcsaxes/core.py
+++ b/wcsaxes/core.py
@@ -150,12 +150,11 @@ def plot_coord(self, *args, **kwargs):
         matplotlib.Axes.plot : This method is called from this function with all arguments passed to it.
 
         """
-        args = list(args)
-        coord_instances = (SkyCoord, BaseCoordinateFrame)
-        if isinstance(args[0], coord_instances):
+
+        if isinstance(args[0], (SkyCoord, BaseCoordinateFrame)):
 
             # Extract the frame from the first argument.
-            frame0 = args.pop(0)
+            frame0 = args[0]
             if isinstance(frame0, SkyCoord):
                 frame0 = frame0.frame
 
@@ -174,9 +173,9 @@ def plot_coord(self, *args, **kwargs):
                                 " as it is automatically determined by the input coordinate frame.")
 
             transform = self.get_transform(frame0)
-            kwargs.update({'transform':transform})
+            kwargs.update({'transform': transform})
 
-            args = plot_data + args
+            args = tuple(plot_data) + args[1:]
 
         super(WCSAxes, self).plot(*args, **kwargs)
 
diff --git a/wcsaxes/tests/test_images.py b/wcsaxes/tests/test_images.py
index 122affa..fa73a73 100644
--- a/wcsaxes/tests/test_images.py
+++ b/wcsaxes/tests/test_images.py
@@ -196,7 +196,7 @@ def test_cube_slice_image_lonlat(self):
         return fig
 
     @remote_data
-    @pytest.mark.mpl_image_compare(baseline_dir=baseline_dir, filename='plot_coord.png', tolerance=1.5)
+    @pytest.mark.mpl_image_compare(baseline_dir=baseline_dir, tolerance=1.5)
     def test_plot_coord(self):
         fig = plt.figure(figsize=(6, 6))
         ax = fig.add_axes([0.15, 0.15, 0.8, 0.8],
@@ -205,13 +205,13 @@ def test_plot_coord(self):
         ax.set_xlim(-0.5, 720.5)
         ax.set_ylim(-0.5, 720.5)
 
-        c = SkyCoord(266*u.deg, -29*u.deg)
+        c = SkyCoord(266 * u.deg, -29 * u.deg)
         ax.plot_coord(c, 'o')
 
         return fig
 
     @remote_data
-    @pytest.mark.mpl_image_compare(baseline_dir=baseline_dir, filename='plot_line.png', tolerance=1.5)
+    @pytest.mark.mpl_image_compare(baseline_dir=baseline_dir, tolerance=1.5)
     def test_plot_line(self):
         fig = plt.figure(figsize=(6, 6))
         ax = fig.add_axes([0.15, 0.15, 0.8, 0.8],
@@ -220,7 +220,7 @@ def test_plot_line(self):
         ax.set_xlim(-0.5, 720.5)
         ax.set_ylim(-0.5, 720.5)
 
-        c = SkyCoord([266, 266.8]*u.deg, [-29, -28.9]*u.deg)
+        c = SkyCoord([266, 266.8] * u.deg, [-29, -28.9] * u.deg)
         ax.plot_coord(c)
 
         return fig