Make sure mutability of dict arguments won't cause problems

One could argue that a pattern of "arg: dict | None = None" followed by "self.param = arg or dict()" is better, but that would make for an inconsistent pattern in cases where the default argument is not None.

manimlib/animation/transform_matching_parts.py

@@ -35,13 +35,14 @@ class TransformMatchingParts(AnimationGroup):
         target_mobject: Mobject,
         transform_mismatches: bool = False,
         fade_transform_mismatches: bool = False,
-        key_map: dict = dict(),
+        key_map: dict | None = None,
         **kwargs
     ):
         assert(isinstance(mobject, self.mobject_type))
         assert(isinstance(target_mobject, self.mobject_type))
         source_map = self.get_shape_map(mobject)
         target_map = self.get_shape_map(target_mobject)
+        key_map = key_map or dict()
 
         # Create two mobjects whose submobjects all match each other
         # according to whatever keys are used for source_map and

manimlib/mobject/coordinate_systems.py

@@ -399,6 +399,7 @@ class CoordinateSystem(ABC):
 
 
 class Axes(VGroup, CoordinateSystem):
+    default_x_axis_config: dict = dict()
     default_y_axis_config: dict = dict(line_to_number_direction=LEFT)
 
     def __init__(
@@ -418,7 +419,9 @@ class Axes(VGroup, CoordinateSystem):
         self.x_axis = self.create_axis(
             self.x_range,
             axis_config=merge_dicts_recursively(
-                axis_config, x_axis_config
+                self.default_x_axis_config,
+                axis_config,
+                x_axis_config
             ),
             length=width,
         )
@@ -503,7 +506,10 @@ class ThreeDAxes(Axes):
         self.z_range = z_range
         self.z_axis = self.create_axis(
             self.z_range,
-            axis_config=merge_dicts_recursively(kwargs.get("axes_config", {}), z_axis_config),
+            axis_config=merge_dicts_recursively(
+                kwargs.get("axes_config", {}),
+                z_axis_config
+            ),
             length=depth,
         )
         self.z_axis.rotate(-PI / 2, UP, about_point=ORIGIN)
@@ -584,8 +590,8 @@ class NumberPlane(Axes):
             y_axis_config=y_axis_config,
             **kwargs
         )
-        self.background_line_style = background_line_style
+        self.background_line_style = dict(background_line_style)
-        self.faded_line_style = faded_line_style
+        self.faded_line_style = dict(faded_line_style)
         self.faded_line_ratio = faded_line_ratio
         self.make_smooth_after_applying_functions = make_smooth_after_applying_functions
         self.init_background_lines()

manimlib/mobject/number_line.py

@@ -54,12 +54,12 @@ class NumberLine(Line):
         self.tick_size = tick_size
         self.longer_tick_multiple = longer_tick_multiple
         self.tick_offset = tick_offset
-        self.numbers_with_elongated_ticks = numbers_with_elongated_ticks
+        self.numbers_with_elongated_ticks = list(numbers_with_elongated_ticks)
         self.line_to_number_direction = line_to_number_direction
         self.line_to_number_buff = line_to_number_buff
         self.include_tip = include_tip
-        self.tip_config = tip_config
+        self.tip_config = dict(tip_config)
-        self.decimal_number_config = decimal_number_config
+        self.decimal_number_config = dict(decimal_number_config)
         self.numbers_to_exclude = numbers_to_exclude
 
         self.x_min, self.x_max = x_range[:2]
@@ -217,5 +217,5 @@ class UnitInterval(NumberLine):
             x_range=x_range,
             unit_size=unit_size,
             numbers_with_elongated_ticks=numbers_with_elongated_ticks,
-            decimal_number_config   =decimal_number_config,
+            decimal_number_config=decimal_number_config,
         )

manimlib/mobject/numbers.py

@@ -45,7 +45,7 @@ class DecimalNumber(VMobject):
         self.include_background_rectangle = include_background_rectangle
         self.edge_to_fix = edge_to_fix
         self.font_size = font_size
-        self.text_config = text_config
+        self.text_config = dict(text_config)
 
         super().__init__(
             color=color,

manimlib/mobject/svg/mtex_mobject.py

@@ -51,7 +51,7 @@ class MTex(StringMobject):
         self.alignment = alignment
         self.template = template
         self.additional_preamble = additional_preamble
-        self.tex_to_color_map = tex_to_color_map
+        self.tex_to_color_map = dict(tex_to_color_map)
 
         super().__init__(
             tex_string,

manimlib/mobject/svg/string_mobject.py

@@ -68,7 +68,7 @@ class StringMobject(SVGMobject, ABC):
         **kwargs
     ):
         self.string = string
-        self.path_string_config = path_string_config
+        self.path_string_config = dict(path_string_config)
         self.base_color = base_color or WHITE
         self.isolate = isolate
         self.protect = protect

manimlib/mobject/svg/svg_mobject.py

@@ -64,8 +64,8 @@ class SVGMobject(VMobject):
         **kwargs
     ):
         self.file_name = file_name or self.file_name
-        self.svg_default = svg_default
+        self.svg_default = dict(svg_default)
-        self.path_string_config = path_string_config
+        self.path_string_config = dict(path_string_config)
         self.height = height
 
         super().__init__(**kwargs )

manimlib/mobject/svg/tex_mobject.py

@@ -7,7 +7,7 @@ import re
 from manimlib.constants import BLACK, WHITE, GREY_C
 from manimlib.constants import DOWN, LEFT, RIGHT, UP
 from manimlib.constants import FRAME_WIDTH
-from manimlib.constants import MED_LARGE_BUFF, MED_SMALL_BUFF, SMALL_BUFF
+from manimlib.constants import MED_LARGE_BUFF, SMALL_BUFF
 from manimlib.mobject.geometry import Line
 from manimlib.mobject.svg.svg_mobject import SVGMobject
 from manimlib.mobject.types.vectorized_mobject import VGroup
@@ -46,8 +46,8 @@ class SingleStringTex(SVGMobject):
         **kwargs
     ):
         self.tex_string = tex_string
-        self.svg_default = svg_default
+        self.svg_default = dict(svg_default)
-        self.path_string_config = path_string_config
+        self.path_string_config = dict(path_string_config)
         self.font_size = font_size
         self.alignment = alignment
         self.math_mode = math_mode

manimlib/mobject/vector_field.py

@@ -140,7 +140,7 @@ class VectorField(VGroup):
         self.color_map = color_map
         self.length_func = length_func
         self.opacity = opacity
-        self.vector_config = vector_config
+        self.vector_config = dict(vector_config)
 
         self.value_to_rgb = get_rgb_gradient_function(
             *self.magnitude_range, self.color_map,

manimlib/scene/scene.py

@@ -82,7 +82,7 @@ class Scene(object):
         if self.preview:
             from manimlib.window import Window
             self.window = Window(scene=self, **window_config)
-            self.camera_config.update(camera_config)
+            self.camera_config= {**self.camera_config, **camera_config}
             self.camera_config["ctx"] = self.window.ctx
             self.camera_config["fps"] = 30  # Where's that 30 from?
             self.undo_stack = []