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MLC122: ApplyMethod receives a call result, not the bound method

qual reports MLC122 when the first positional argument of ApplyMethod(...) is the result of calling a fluent mobject method, as in ApplyMethod(mob.shift(RIGHT)).

ApplyMethod(method, *args) expects an uncalled bound mobject method; it invokes the method itself during interpolation. Passing the call result mutates the mobject before the play starts and fails at animation build time, because the returned mobject is not the callable ApplyMethod requires.

  • Default severity: error
  • Minimum confidence: high
  • Implementation phase: 1
  • Fix: splitting into ApplyMethod(mob.method, args...) is offered as an UNSAFE suggestion for simple calls

The inner call must conclusively resolve to a curated returns_self mobject method; unknown callees stay silent.

Wrong

class Demo(Scene):
    def construct(self):
        square = Square()
        self.play(ApplyMethod(square.shift(RIGHT)))

class Demo(Scene):
    def construct(self):
        square = Square()
        self.play(ApplyMethod(square.shift, RIGHT))
        # or, in current Manim style:
        self.play(square.animate.shift(RIGHT))