fix: Improve mergeStructs: Safely Combine Refiners and Prevent Runtime Errors

[ekuboo100]

Description

Fix refactors the mergeStructs function in packages/snaps-utils/src/structs.ts to improve its robustness and prevent potential runtime errors. Previously, the function assumed that every struct in the merge would have a valid refiner function. In practice, this is not always guaranteed and could lead to errors if a struct does not implement a refiner.

With this update, the function now explicitly checks whether struct.refiner is a function before calling it. This ensures that only valid refiners are invoked, making the code more reliable and easier to maintain.

Changes

• Updated the mergeStructs function to safely combine refiners from multiple structs.
• Added a type check to ensure struct.refiner is a function before invoking it.

References

Regular expression
WikipediaReDoS
WikipediaTime complexity
Static Analysis for Regular Expression

[Mrtenz]

struct.refiner is required to be set by TypeScript. Do you have any way to actually reproduce a runtime error caused by this function?