Fixes for Cartopy 0.18

.travis.yml

@@ -62,10 +62,12 @@ matrix:
       env:
         - TASK="coverage"
         - VERSIONS="git+git://github.com/hgrecco/pint@master#egg=pint git+git://github.com/pydata/xarray@master#egg=xarray"
+        - EXTRA_PACKAGES="$EXTRA_PACKAGES setuptools_scm[toml]"
     - python: "3.8-dev"
       env:
         - TASK="docs"
         - VERSIONS="git+git://github.com/hgrecco/pint@master#egg=pint git+git://github.com/pydata/xarray@master#egg=xarray"
+        - EXTRA_PACKAGES="$EXTRA_PACKAGES setuptools_scm[toml]"
   allow_failures:
     - python: "3.8-dev"
     - python: nightly

docs/index.rst

@@ -143,4 +143,4 @@ Related Projects
 .. _netCDF: https://www.unidata.ucar.edu/software/netcdf/
 .. _siphon: https://unidata.github.io/siphon/
 .. _Unidata Python Gallery: https://unidata.github.io/python-training/gallery/gallery-home
-__ https://www.unidata.ucar.edu/software/thredds/current/tds/
+__ https://www.unidata.ucar.edu/software/tds/current/

docs/references.rst

@@ -78,8 +78,8 @@ References
            doi:`10.1175/1520-0426(1987)004%3C0239:DOTPCO%3E2.0.CO;2
            <https://doi.org/10.1175/1520-0426(1987)004%3C0239:DOTPCO%3E2.0.CO;2>`_.
 
-.. [FCMR192003] Federal Coordinator for Meteorological Services and Supporting Research: Report on
-           Wind Chill Temperature and Extreme Heat Indices: Evaluation and Improvement
+.. [FCMR192003] Federal Coordinator for Meteorological Services and Supporting Research: Report
+           on Wind Chill Temperature and Extreme Heat Indices: Evaluation and Improvement
            Projects. Washington, DC: Office of the Federal Coordinator for Meteorological
            Services and Supporting Research, 2003.
            `FCM-R19-2003 <_static/FCM-R19-2003-WindchillReport.pdf>`_, 75 pp.
@@ -92,7 +92,8 @@ References
 .. [Garratt1994] Garratt, J.R., 1994: *The Atmospheric Boundary Layer*. Cambridge
            University Press, 316 pp.
 
-.. [Holton2004] Holton, J. R., 2004: *An Introduction to Dynamic Meteorology*. 4th ed. Academic Press, 535 pp.
+.. [Holton2004] Holton, J. R., 2004: *An Introduction to Dynamic Meteorology*. 4th ed.
+           Academic Press, 535 pp.
 
 .. [Koch1983] Koch, S. E., M. DesJardins, and P. J. Kocin, 1983: An interactive Barnes
            objective map analysis scheme for use with satellite and conventional data.
@@ -122,8 +123,8 @@ References
 .. [Rochette2006] Rochette, Scott M., and Patrick S. Market. "A primer on the
                   ageostrophic wind." Natl. Weather Dig. 30 (2006): 17-28.
 
-.. [Rothfusz1990] Rothfusz, L.P.: *The Heat Index "Equation"*. Fort Worth, TX: Scientific Services
-           Division, NWS Southern Region Headquarters, 1990.
+.. [Rothfusz1990] Rothfusz, L.P.: *The Heat Index "Equation"*. Fort Worth, TX: Scientific
+           Services Division, NWS Southern Region Headquarters, 1990.
            `SR90-23 <_static/rothfusz-1990-heat-index-equation.pdf>`_, 2 pp.
 
 .. [Salby1996] Salby, M. L., 1996: *Fundamentals of Atmospheric Physics*.

examples/meteogram_metpy.py

@@ -80,10 +80,10 @@ def plot_winds(self, ws, wd, wsmax, plot_range=None):
         ax7.set_ylabel('Wind\nDirection\n(degrees)', multialignment='center')
         ax7.set_ylim(0, 360)
         ax7.set_yticks(np.arange(45, 405, 90), ['NE', 'SE', 'SW', 'NW'])
-        lns = ln1 + ln2 + ln3
-        labs = [l.get_label() for l in lns]
+        lines = ln1 + ln2 + ln3
+        labs = [line.get_label() for line in lines]
         ax7.xaxis.set_major_formatter(mpl.dates.DateFormatter('%d/%H UTC'))
-        ax7.legend(lns, labs, loc='upper center',
+        ax7.legend(lines, labs, loc='upper center',
                    bbox_to_anchor=(0.5, 1.2), ncol=3, prop={'size': 12})
 
     def plot_thermo(self, t, td, plot_range=None):
@@ -111,11 +111,11 @@ def plot_thermo(self, t, td, plot_range=None):
 
         ax_twin = self.ax2.twinx()
         ax_twin.set_ylim(plot_range[0], plot_range[1], plot_range[2])
-        lns = ln4 + ln5
-        labs = [l.get_label() for l in lns]
+        lines = ln4 + ln5
+        labs = [line.get_label() for line in lines]
         ax_twin.xaxis.set_major_formatter(mpl.dates.DateFormatter('%d/%H UTC'))
 
-        self.ax2.legend(lns, labs, loc='upper center',
+        self.ax2.legend(lines, labs, loc='upper center',
                         bbox_to_anchor=(0.5, 1.2), ncol=2, prop={'size': 12})
 
     def plot_rh(self, rh, plot_range=None):

src/metpy/__init__.py

@@ -32,6 +32,6 @@
 os.environ['PINT_ARRAY_PROTOCOL_FALLBACK'] = '0'
 
 from ._version import get_version  # noqa: E402
-from .xarray import *  # noqa: F401, F403
+from .xarray import *  # noqa: F401, F403, E402
 __version__ = get_version()
 del get_version

src/metpy/calc/basic.py

@@ -136,8 +136,7 @@ def wind_components(speed, wind_direction):
     --------
     >>> from metpy.units import units
     >>> metpy.calc.wind_components(10. * units('m/s'), 225. * units.deg)
-    (<Quantity(7.071067811865475, 'meter / second')>,
-     <Quantity(7.071067811865477, 'meter / second')>)
+     (<Quantity(7.07106781, 'meter / second')>, <Quantity(7.07106781, 'meter / second')>)
 
     """
     wind_direction = _check_radians(wind_direction, max_radians=4 * np.pi)

src/metpy/calc/thermo.py

@@ -124,7 +124,7 @@ def potential_temperature(pressure, temperature):
     --------
     >>> from metpy.units import units
     >>> metpy.calc.potential_temperature(800. * units.mbar, 273. * units.kelvin)
-    <Quantity(290.9665329591884, 'kelvin')>
+    <Quantity(290.966533, 'kelvin')>
 
     """
     return temperature / exner_function(pressure)

src/metpy/plots/_mpl.py

@@ -100,6 +100,12 @@ def scattertext(self, x, y, texts, loc=(0, 0), **kw):
 
         # Add it to the axes and update range
         self.add_artist(text_obj)
+
+        # Matplotlib at least up to 3.2.2 does not properly clip text with paths, so
+        # work-around by setting to the bounding box of the Axes
+        # TODO: Remove when fixed in our minimum supported version of matplotlib
+        text_obj.clipbox = self.bbox
+
         self.update_datalim(text_obj.get_datalim(self.transData))
         self.autoscale_view()
         return text_obj
@@ -219,8 +225,9 @@ def draw(self, renderer):
                     if renderer.flipy():
                         y = canvash - y
 
-                    # Can simplify next two lines once support for matplotlib<3.1 is dropped
-                    check_line = getattr(self, '_preprocess_math', self.is_math_text)
+                    # Can simplify next three lines once support for matplotlib<3.1 is dropped
+                    is_math_text = getattr(self, 'is_math_text', False)
+                    check_line = getattr(self, '_preprocess_math', is_math_text)
                     clean_line, ismath = check_line(line)
 
                     if self.get_path_effects():

src/metpy/plots/cartopy_utils.py

@@ -3,28 +3,39 @@
 # SPDX-License-Identifier: BSD-3-Clause
 """Cartopy specific mapping utilities."""
 
+import cartopy.crs as ccrs
 import cartopy.feature as cfeature
 
 from ..cbook import get_test_data
 
 
-class MetPyMapFeature(cfeature.NaturalEarthFeature):
-    """A simple interface to US County shapefiles."""
+class MetPyMapFeature(cfeature.Feature):
+    """A simple interface to MetPy-included shapefiles."""
 
     def __init__(self, name, scale, **kwargs):
-        """Create USCountiesFeature instance."""
-        super().__init__('', name, scale, **kwargs)
+        """Create MetPyMapFeature instance."""
+        super().__init__(ccrs.PlateCarree(), **kwargs)
+        self.name = name
+
+        if isinstance(scale, str):
+            scale = cfeature.Scaler(scale)
+        self.scaler = scale
 
     def geometries(self):
         """Return an iterator of (shapely) geometries for this feature."""
         import cartopy.io.shapereader as shapereader
         # Ensure that the associated files are in the cache
-        fname = '{}_{}'.format(self.name, self.scale)
+        fname = '{}_{}'.format(self.name, self.scaler.scale)
         for extension in ['.dbf', '.shx']:
             get_test_data(fname + extension)
         path = get_test_data(fname + '.shp', as_file_obj=False)
         return iter(tuple(shapereader.Reader(path).geometries()))
 
+    def intersecting_geometries(self, extent):
+        """Return geometries that intersect the extent."""
+        self.scaler.scale_from_extent(extent)
+        return super().intersecting_geometries(extent)
+
     def with_scale(self, new_scale):
         """
         Return a copy of the feature with a new scale.

src/metpy/plots/skewt.py

@@ -8,6 +8,7 @@
 """
 
 from contextlib import ExitStack
+import warnings
 
 import matplotlib
 from matplotlib.axes import Axes
@@ -126,7 +127,11 @@ class SkewXAxis(maxis.XAxis):
     """
 
     def _get_tick(self, major):
-        return SkewXTick(self.axes, None, '', major=major)
+        # Warning stuff can go away when we only support Matplotlib >=3.3
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', getattr(
+                matplotlib, 'MatplotlibDeprecationWarning', DeprecationWarning))
+            return SkewXTick(self.axes, None, label=None, major=major)
 
     # Needed to properly handle tight bbox
     def _get_tick_bboxes(self, ticks, renderer):

src/metpy/plots/wx_symbols.py

@@ -106,13 +106,13 @@ def __init__(self, num, font_start, font_jumps=None, char_jumps=None):
                 font_point += 1
 
     @staticmethod
-    def _safe_pop(l):
+    def _safe_pop(lst):
         """Safely pop from a list.
 
         Returns None if list empty.
 
         """
-        return l.pop(0) if l else None
+        return lst.pop(0) if lst else None
 
     def __call__(self, code):
         """Return the Unicode code point corresponding to `code`."""

src/metpy/testing.py

@@ -199,17 +199,6 @@ def set_agg_backend():
         plt.switch_backend(prev_backend)
 
 
-@pytest.fixture(autouse=True)
-def patch_round(monkeypatch):
-    """Fixture to patch builtin round using numpy's.
-
-    This works around the fact that built-in round changed between Python 2 and 3. This
-    is probably not needed once we're testing on matplotlib 2.0, which has been updated
-    to use numpy's throughout.
-    """
-    monkeypatch.setitem(__builtins__, 'round', np.round)
-
-
 def check_and_silence_warning(warn_type):
     """Decorate a function to swallow some warning type, making sure they are present.
 

tests/calc/test_thermo.py

@@ -808,6 +808,7 @@ def test_most_unstable_parcel():
     assert_almost_equal(ret[2], 19.0 * units.degC, 6)
 
 
+@pytest.mark.filterwarnings('ignore:invalid value:RuntimeWarning')
 def test_isentropic_pressure():
     """Test calculation of isentropic pressure function."""
     lev = [100000., 95000., 90000., 85000.] * units.Pa
@@ -819,8 +820,7 @@ def test_isentropic_pressure():
     tmp[:, :, -1] = np.nan
     tmpk = tmp * units.kelvin
     isentlev = [296.] * units.kelvin
-    with pytest.warns(RuntimeWarning, match='invalid value'):
-        isentprs = isentropic_interpolation(isentlev, lev, tmpk)
+    isentprs = isentropic_interpolation(isentlev, lev, tmpk)
     trueprs = np.ones((1, 5, 5)) * (1000. * units.hPa)
     trueprs[:, :, -1] = np.nan
     assert isentprs[0].shape == (1, 5, 5)

tests/plots/test_cartopy_utils.py

@@ -10,7 +10,7 @@
 
 from metpy.plots import USCOUNTIES, USSTATES
 # Fixtures to make sure we have the right backend and consistent round
-from metpy.testing import patch_round, set_agg_backend  # noqa: F401, I202
+from metpy.testing import set_agg_backend  # noqa: F401, I202
 
 MPL_VERSION = matplotlib.__version__[:3]
 

tests/plots/test_declarative.py

@@ -10,6 +10,7 @@
 import cartopy.crs as ccrs
 import cartopy.feature as cfeature
 import matplotlib
+import numpy as np
 import pandas as pd
 import pytest
 from traitlets import TraitError
@@ -77,8 +78,22 @@ def test_declarative_contour():
     return pc.figure
 
 
+@pytest.fixture
+def fix_is_closed_polygon(monkeypatch):
+    """Fix matplotlib.contour._is_closed_polygons for tests.
+
+    Needed because for Matplotlib<3.3, the internal matplotlib.contour._is_closed_polygon
+    uses strict floating point equality. This causes the test below to yield different
+    results for macOS vs. Linux/Windows.
+
+    """
+    monkeypatch.setattr(matplotlib.contour, '_is_closed_polygon',
+                        lambda X: np.allclose(X[0], X[-1], rtol=1e-10, atol=1e-13),
+                        raising=False)
+
+
 @pytest.mark.mpl_image_compare(remove_text=True, tolerance=0.035)
-def test_declarative_contour_options():
+def test_declarative_contour_options(fix_is_closed_polygon):
     """Test making a contour plot."""
     data = xr.open_dataset(get_test_data('narr_example.nc', as_file_obj=False))
 
@@ -107,7 +122,7 @@ def test_declarative_contour_options():
 
 
 @pytest.mark.mpl_image_compare(remove_text=True, tolerance=0.035)
-def test_declarative_contour_convert_units():
+def test_declarative_contour_convert_units(fix_is_closed_polygon):
     """Test making a contour plot."""
     data = xr.open_dataset(get_test_data('narr_example.nc', as_file_obj=False))
 
@@ -419,7 +434,7 @@ def test_declarative_barb_earth_relative():
     return pc.figure
 
 
-@pytest.mark.mpl_image_compare(remove_text=True, tolerance=0.346)
+@pytest.mark.mpl_image_compare(remove_text=True, tolerance=0.347)
 def test_declarative_barb_gfs():
     """Test making a contour plot."""
     data = xr.open_dataset(get_test_data('GFS_test.nc', as_file_obj=False))
@@ -542,7 +557,7 @@ def test_declarative_sfc_obs_changes():
     return pc.figure
 
 
-@pytest.mark.mpl_image_compare(remove_text=True, tolerance=0)
+@pytest.mark.mpl_image_compare(remove_text=True, tolerance=0.00586)
 def test_declarative_colored_barbs():
     """Test making a surface plot with a colored barb (gh-1274)."""
     data = pd.read_csv(get_test_data('SFC_obs.csv', as_file_obj=False),
@@ -575,7 +590,8 @@ def test_declarative_colored_barbs():
 
 
 @pytest.mark.mpl_image_compare(remove_text=True,
-                               tolerance={'3.1': 9.771, '2.1': 9.771}.get(MPL_VERSION, 0.))
+                               tolerance={'3.1': 9.771,
+                                          '2.1': 9.771}.get(MPL_VERSION, 0.00651))
 def test_declarative_sfc_obs_full():
     """Test making a full surface observation plot."""
     data = pd.read_csv(get_test_data('SFC_obs.csv', as_file_obj=False),

tests/plots/test_skewt.py

@@ -11,7 +11,7 @@
 
 from metpy.plots import Hodograph, SkewT
 # Fixtures to make sure we have the right backend and consistent round
-from metpy.testing import patch_round, set_agg_backend  # noqa: F401, I202
+from metpy.testing import set_agg_backend  # noqa: F401, I202
 from metpy.units import units
 
 

tests/plots/test_station_plot.py

@@ -13,7 +13,7 @@
 from metpy.plots import (current_weather, high_clouds, nws_layout, simple_layout,
                          sky_cover, StationPlot, StationPlotLayout)
 # Fixtures to make sure we have the right backend and consistent round
-from metpy.testing import patch_round, set_agg_backend  # noqa: F401, I202
+from metpy.testing import set_agg_backend  # noqa: F401, I202
 from metpy.units import units
 
 
@@ -279,30 +279,30 @@ def wind_plot():
     return u, v, x, y
 
 
-@pytest.mark.mpl_image_compare(tolerance=0.00323, remove_text=True)
+@pytest.mark.mpl_image_compare(tolerance=0.00434, remove_text=True)
 def test_barb_projection(wind_plot):
     """Test that barbs are properly projected (#598)."""
     u, v, x, y = wind_plot
 
     # Plot and check barbs (they should align with grid lines)
     fig = plt.figure()
     ax = fig.add_subplot(1, 1, 1, projection=ccrs.LambertConformal())
-    ax.gridlines(xlocs=[-135, -120, -105, -90, -75, -60, -45])
+    ax.gridlines(xlocs=[-120, -105, -90, -75, -60], ylocs=np.arange(24, 55, 6))
     sp = StationPlot(ax, x, y, transform=ccrs.PlateCarree())
     sp.plot_barb(u, v)
 
     return fig
 
 
-@pytest.mark.mpl_image_compare(tolerance=0.00205, remove_text=True)
+@pytest.mark.mpl_image_compare(tolerance=0.00382, remove_text=True)
 def test_arrow_projection(wind_plot):
     """Test that arrows are properly projected."""
     u, v, x, y = wind_plot
 
     # Plot and check barbs (they should align with grid lines)
     fig = plt.figure()
     ax = fig.add_subplot(1, 1, 1, projection=ccrs.LambertConformal())
-    ax.gridlines(xlocs=[-135, -120, -105, -90, -75, -60, -45])
+    ax.gridlines(xlocs=[-120, -105, -90, -75, -60], ylocs=np.arange(24, 55, 6))
     sp = StationPlot(ax, x, y, transform=ccrs.PlateCarree())
     sp.plot_arrow(u, v)
     sp.plot_arrow(u, v)  # plot_arrow used twice to hit removal if statement