CustomRoute's transitionsBuilder called every frame

[snackva]

I'm coding a custom transition for a route by passing the transitionsBuilder argument to the CustomRoute constructor.

CustomRoute(
  page: VerificationRoute.page,
  path: "/verification/:planId/:userId",
  guards: [IsAuthenticatedGuard()],
  durationInMilliseconds: slowAnimationDuration.inMilliseconds,
  reverseDurationInMilliseconds: slowAnimationDuration.inMilliseconds,
  transitionsBuilder: verificationTransitionBuilder,
);

The definition of the RouteTransitionsBuilder is the following:

typedef RouteTransitionsBuilder = Widget Function(BuildContext context, Animation<double> animation, Animation<double> secondaryAnimation, Widget child);

The function receives an animation, which can be used for efficient rebuilding of the transition inside the returned Widget. However, by adding a print statement inside the function, I've seen the function gets called on every frame of the animation, defeating the purpose of receiving the Animation object directly (receiving a double with its value ranging from 0 to 1 would do the same).
Can this behaviour be fixed so that the function gets called only once when building the transition?

[snackva]

@Milad-Akarie any info?

[snackva]

@Milad-Akarie no updates?

[snackva]

This issue is addressed by the pull request flutter/flutter#159615.