code: def test_at_boundary(self):
      # Check that a polygon is split and recombined correctly
      # as a result of being on the boundary, determined by tolerance.
  
      exterior = np.array(
          [
              [177.5, -79.912],
              [178.333, -79.946],
              [181.666, -83.494],
              [180.833, -83.570],
              [180.0, -83.620],
              [178.438, -83.333],
              [178.333, -83.312],
              [177.956, -83.888],
              [180.0, -84.086],
              [180.833, -84.318],
              [183.0, -86.0],
              [183.0, -78.0],
              [177.5, -79.912],
          ]
      )
      tring = sgeom.LinearRing(exterior)
  
      tcrs = ccrs.PlateCarree()
      scrs = ccrs.PlateCarree()
  
      rings, mlinestr = tcrs._project_linear_ring(tring, scrs)
  
      # Number of linearstrings
      assert len(mlinestr.geoms) == 4
      assert not rings
  
      # Test area of smallest Polygon that contains all the points in the
      # geometry.
      assert round(abs(mlinestr.convex_hull.area - 2347.7562), 4) == 0
  
file_path: cartopy/lib/cartopy/tests/test_linear_ring.py
imports: import numpy
  import pytest
  import shapely.geometry
  import cartopy.crs
label_desc: Use image node_id 4 for calling the TestMisc obj's underlying member method code with example usage: obj.test_at_boundary() without return types