Modernize code (#218)

* Use f-strings

* Use integers where appropriate

* Refactor generate_random

geojson/base.py

@@ -107,15 +107,15 @@ def to_instance(cls, ob, default=None, strict=False):
                 except UnicodeEncodeError:
                     # If the type contains non-ascii characters, we can assume
                     # it's not a valid GeoJSON type
-                    raise AttributeError(
-                        "{0} is not a GeoJSON type").format(type_)
+                    raise AttributeError(f"{type_} is not a GeoJSON type")
                 geojson_factory = getattr(geojson.factory, type_)
                 instance = geojson_factory(**d)
             except (AttributeError, KeyError) as invalid:
                 if strict:
-                    msg = "Cannot coerce %r into a valid GeoJSON structure: %s"
-                    msg %= (ob, invalid)
-                    raise ValueError(msg)
+                    raise ValueError(
+                        f"Cannot coerce {ob!r} into "
+                        f"a valid GeoJSON structure: {invalid}"
+                    )
                 instance = ob
         return instance
 

geojson/codec.py

@@ -19,7 +19,7 @@ def default(self, obj):
 # Here the defaults are set to only permit valid JSON as per RFC 4267
 
 def _enforce_strict_numbers(obj):
-    raise ValueError("Number %r is not JSON compliant" % obj)
+    raise ValueError(f"Number {obj!r} is not JSON compliant")
 
 
 def dump(obj, fp, cls=GeoJSONEncoder, allow_nan=False, **kwargs):

geojson/geometry.py

@@ -50,7 +50,7 @@ def clean_coordinates(cls, coords, precision):
             elif isinstance(coord, (Real, Decimal)):
                 new_coords.append(round(coord, precision))
             else:
-                raise ValueError("%r is not a JSON compliant number" % coord)
+                raise ValueError(f"{coord!r} is not a JSON compliant number")
         return new_coords
 
 

geojson/utils.py

@@ -87,7 +87,7 @@ def map_tuples(func, obj):
     elif obj['type'] in ['Feature', 'FeatureCollection', 'GeometryCollection']:
         return map_geometries(lambda g: map_tuples(func, g), obj)
     else:
-        raise ValueError("Invalid geometry object %s" % repr(obj))
+        raise ValueError(f"Invalid geometry object {obj!r}")
     return {'type': obj['type'], 'coordinates': coordinates}
 
 
@@ -125,11 +125,11 @@ def map_geometries(func, obj):
         feats = [map_geometries(func, feat) for feat in obj['features']]
         return {'type': obj['type'], 'features': feats}
     else:
-        raise ValueError("Invalid GeoJSON object %s" % repr(obj))
+        raise ValueError(f"Invalid GeoJSON object {obj!r}")
 
 
 def generate_random(featureType, numberVertices=3,
-                    boundingBox=[-180.0, -90.0, 180.0, 90.0]):
+                    boundingBox=[-180, -90, 180, 90]):
     """
     Generates random geojson features depending on the parameters
     passed through.
@@ -152,79 +152,67 @@ def generate_random(featureType, numberVertices=3,
     import random
     import math
 
-    lonMin = boundingBox[0]
-    lonMax = boundingBox[2]
+    lon_min, lat_min, lon_max, lat_max = boundingBox
 
-    def randomLon():
-        return random.uniform(lonMin, lonMax)
+    def random_lon():
+        return random.uniform(lon_min, lon_max)
 
-    latMin = boundingBox[1]
-    latMax = boundingBox[3]
+    def random_lat():
+        return random.uniform(lat_min, lat_max)
 
-    def randomLat():
-        return random.uniform(latMin, latMax)
+    def create_point():
+        return Point((random_lon(), random_lat()))
 
-    def createPoint():
-        return Point((randomLon(), randomLat()))
+    def create_line():
+        return LineString([create_point() for _ in range(numberVertices)])
 
-    def createLine():
-        return LineString([createPoint() for unused in range(numberVertices)])
+    def create_poly():
+        ave_radius = 60
+        ctr_x = 0.1
+        ctr_y = 0.2
+        irregularity = clip(0.1, 0, 1) * math.tau / numberVertices
+        spikeyness = clip(0.5, 0, 1) * ave_radius
 
-    def createPoly():
-        aveRadius = 60
-        ctrX = 0.1
-        ctrY = 0.2
-        irregularity = clip(0.1, 0, 1) * 2 * math.pi / numberVertices
-        spikeyness = clip(0.5, 0, 1) * aveRadius
+        lower = (math.tau / numberVertices) - irregularity
+        upper = (math.tau / numberVertices) + irregularity
+        angle_steps = []
+        for _ in range(numberVertices):
+            angle_steps.append(random.uniform(lower, upper))
+        sum_angle = sum(angle_steps)
 
-        angleSteps = []
-        lower = (2 * math.pi / numberVertices) - irregularity
-        upper = (2 * math.pi / numberVertices) + irregularity
-        sum = 0
-        for i in range(numberVertices):
-            tmp = random.uniform(lower, upper)
-            angleSteps.append(tmp)
-            sum = sum + tmp
-
-        k = sum / (2 * math.pi)
-        for i in range(numberVertices):
-            angleSteps[i] = angleSteps[i] / k
+        k = sum_angle / math.tau
+        angle_steps = [x / k for x in angle_steps]
 
         points = []
-        angle = random.uniform(0, 2 * math.pi)
-
-        for i in range(numberVertices):
-            r_i = clip(random.gauss(aveRadius, spikeyness), 0, 2 * aveRadius)
-            x = ctrX + r_i * math.cos(angle)
-            y = ctrY + r_i * math.sin(angle)
-            x = (x + 180.0) * (abs(lonMin-lonMax) / 360.0) + lonMin
-            y = (y + 90.0) * (abs(latMin-latMax) / 180.0) + latMin
-            x = clip(x, lonMin, lonMax)
-            y = clip(y, latMin, latMax)
+        angle = random.uniform(0, math.tau)
+
+        for angle_step in angle_steps:
+            r_i = clip(random.gauss(ave_radius, spikeyness), 0, 2 * ave_radius)
+            x = ctr_x + r_i * math.cos(angle)
+            y = ctr_y + r_i * math.sin(angle)
+            x = (x + 180) * (abs(lon_min - lon_max) / 360) + lon_min
+            y = (y + 90) * (abs(lat_min - lat_max) / 180) + lat_min
+            x = clip(x, lon_min, lon_max)
+            y = clip(y, lat_min, lat_max)
             points.append((x, y))
-            angle = angle + angleSteps[i]
+            angle += angle_step
 
-        firstVal = points[0]
-        points.append(firstVal)
+        points.append(points[0])  # append first point to the end
         return Polygon([points])
 
-    def clip(x, min, max):
-        if min > max:
+    def clip(x, min_val, max_val):
+        if min_val > max_val:
             return x
-        elif x < min:
-            return min
-        elif x > max:
-            return max
         else:
-            return x
+            return min(max(min_val, x), max_val)
 
     if featureType == 'Point':
-        return createPoint()
+        return create_point()
 
     if featureType == 'LineString':
-        return createLine()
+        return create_line()
 
     if featureType == 'Polygon':
-        return createPoly()
+        return create_poly()
 
     raise ValueError(f"featureType: {featureType} is not supported.")

tests/__init__.py

@@ -7,6 +7,6 @@
                doctest.ELLIPSIS)
 
 _basedir = os.path.dirname(__file__)
-paths = glob.glob("%s/*.txt" % _basedir)
+paths = glob.glob(f"{_basedir}/*.txt")
 test_suite = doctest.DocFileSuite(*paths, **dict(module_relative=False,
                                                  optionflags=optionflags))

tests/test_utils.py

@@ -10,12 +10,12 @@
 
 
 def generate_bbox():
-    min_lat = random.random() * 180.0 - 90.0
-    max_lat = random.random() * 180.0 - 90.0
+    min_lat = random.random() * 180 - 90
+    max_lat = random.random() * 180 - 90
     if min_lat > max_lat:
         min_lat, max_lat = max_lat, min_lat
-    min_lon = random.random() * 360.0 - 180.0
-    max_lon = random.random() * 360.0 - 180.0
+    min_lon = random.random() * 360 - 180
+    max_lon = random.random() * 360 - 180
     if min_lon > max_lon:
         min_lon, max_lon = max_lon, min_lon
     return [min_lon, min_lat, max_lon, max_lat]
@@ -46,7 +46,7 @@ def check_point_bbox(point, bbox):
 class TestGenerateRandom(unittest.TestCase):
     def test_simple_polygon(self):
         for _ in range(5000):
-            bbox = [-180.0, -90.0, 180.0, 90.0]
+            bbox = [-180, -90, 180, 90]
             result = generate_random('Polygon')
             self.assertIsInstance(result, geojson.geometry.Polygon)
             self.assertTrue(geojson.geometry.check_polygon(result))