Changed hatch density typing to float. Added FutureWarning for cases where conversion would change behaviour

borgesaugusto · borgesaugusto · commit f068c37f090a · 2023-10-08T14:54:08.000+02:00
diff --git a/lib/matplotlib/hatch.py b/lib/matplotlib/hatch.py
@@ -133,15 +133,15 @@ class SmallCircles(Circles):
     size = 0.2
 
     def __init__(self, hatch, density):
-        self.num_rows = (hatch.count('o')) * density
+        self.num_rows = int((hatch.count('o')) * density)
         super().__init__(hatch, density)
 
 
 class LargeCircles(Circles):
     size = 0.35
 
     def __init__(self, hatch, density):
-        self.num_rows = (hatch.count('O')) * density
+        self.num_rows = int((hatch.count('O')) * density)
         super().__init__(hatch, density)
 
 
@@ -150,7 +150,7 @@ class SmallFilledCircles(Circles):
     filled = True
 
     def __init__(self, hatch, density):
-        self.num_rows = (hatch.count('.')) * density
+        self.num_rows = int((hatch.count('.')) * density)
         super().__init__(hatch, density)
 
 
@@ -159,7 +159,7 @@ class Stars(Shapes):
     filled = True
 
     def __init__(self, hatch, density):
-        self.num_rows = (hatch.count('*')) * density
+        self.num_rows = int((hatch.count('*')) * density)
         path = Path.unit_regular_star(5)
         self.shape_vertices = path.vertices
         self.shape_codes = np.full(len(self.shape_vertices), Path.LINETO,
@@ -196,13 +196,18 @@ def _validate_hatch_pattern(hatch):
             )
 
 
-def get_path(hatchpattern, density=6):
+def get_path(hatchpattern, density=6.0):
     """
     Given a hatch specifier, *hatchpattern*, generates Path to render
     the hatch in a unit square.  *density* is the number of lines per
     unit square.
     """
-    density = int(density)
+    if int(density) != density:
+        _api.warn_external("Passing a floating point density will result in "
+                           "a behavior change due to float to int conversion."
+                           f"Value density ({density}) will be used "
+                           f"instead of {int(density)} to calculate lines",
+                           category=FutureWarning)
 
     patterns = [hatch_type(hatchpattern, density)
                 for hatch_type in _hatch_types]
diff --git a/lib/matplotlib/hatch.pyi b/lib/matplotlib/hatch.pyi
@@ -8,61 +8,61 @@ class HatchPatternBase: ...
 class HorizontalHatch(HatchPatternBase):
     num_lines: int
     num_vertices: int
-    def __init__(self, hatch: str, density: int) -> None: ...
+    def __init__(self, hatch: str, density: float) -> None: ...
     def set_vertices_and_codes(self, vertices: ArrayLike, codes: ArrayLike) -> None: ...
 
 class VerticalHatch(HatchPatternBase):
     num_lines: int
     num_vertices: int
-    def __init__(self, hatch: str, density: int) -> None: ...
+    def __init__(self, hatch: str, density: float) -> None: ...
     def set_vertices_and_codes(self, vertices: ArrayLike, codes: ArrayLike) -> None: ...
 
 class NorthEastHatch(HatchPatternBase):
     num_lines: int
     num_vertices: int
-    def __init__(self, hatch: str, density: int) -> None: ...
+    def __init__(self, hatch: str, density: float) -> None: ...
     def set_vertices_and_codes(self, vertices: ArrayLike, codes: ArrayLike) -> None: ...
 
 class SouthEastHatch(HatchPatternBase):
     num_lines: int
     num_vertices: int
-    def __init__(self, hatch: str, density: int) -> None: ...
+    def __init__(self, hatch: str, density: float) -> None: ...
     def set_vertices_and_codes(self, vertices: ArrayLike, codes: ArrayLike) -> None: ...
 
 class Shapes(HatchPatternBase):
     filled: bool
     num_shapes: int
     num_vertices: int
-    def __init__(self, hatch: str, density: int) -> None: ...
+    def __init__(self, hatch: str, density: float) -> None: ...
     def set_vertices_and_codes(self, vertices: ArrayLike, codes: ArrayLike) -> None: ...
 
 class Circles(Shapes):
     shape_vertices: np.ndarray
     shape_codes: np.ndarray
-    def __init__(self, hatch: str, density: int) -> None: ...
+    def __init__(self, hatch: str, density: float) -> None: ...
 
 class SmallCircles(Circles):
     size: float
     num_rows: int
-    def __init__(self, hatch: str, density: int) -> None: ...
+    def __init__(self, hatch: str, density: float) -> None: ...
 
 class LargeCircles(Circles):
     size: float
     num_rows: int
-    def __init__(self, hatch: str, density: int) -> None: ...
+    def __init__(self, hatch: str, density: float) -> None: ...
 
 class SmallFilledCircles(Circles):
     size: float
     filled: bool
     num_rows: int
-    def __init__(self, hatch: str, density: int) -> None: ...
+    def __init__(self, hatch: str, density: float) -> None: ...
 
 class Stars(Shapes):
     size: float
     filled: bool
     num_rows: int
     shape_vertices: np.ndarray
     shape_codes: np.ndarray
-    def __init__(self, hatch: str, density: int) -> None: ...
+    def __init__(self, hatch: str, density: float) -> None: ...
 
-def get_path(hatchpattern: str, density: int = ...) -> Path: ...
+def get_path(hatchpattern: str, density: float = ...) -> Path: ...
diff --git a/lib/matplotlib/path.py b/lib/matplotlib/path.py
@@ -1024,7 +1024,7 @@ def wedge(cls, theta1, theta2, n=None):
 
     @staticmethod
     @lru_cache(8)
-    def hatch(hatchpattern, density=6):
+    def hatch(hatchpattern, density=6.0):
         """
         Given a hatch specifier, *hatchpattern*, generates a `Path` that
         can be used in a repeated hatching pattern.  *density* is the
diff --git a/lib/matplotlib/tests/test_path.py b/lib/matplotlib/tests/test_path.py
@@ -539,3 +539,13 @@ def test_cleanup_closepoly():
         cleaned = p.cleaned(remove_nans=True)
         assert len(cleaned) == 1
         assert cleaned.codes[0] == Path.STOP
+
+
+def test_hatch_density_integer_to_float():
+    with pytest.warns(FutureWarning,
+                      match="behavior change due to float to int conversion."):
+        Path.hatch("x", 6.6)
+
+
+def test_hatch_density_integer():
+    Path.hatch("x", 2.0)
