Sure. In Rust there's a function called [`str::repeat`](https://doc.rust-lang.org/std/primitive.str.html#method.repeat https://doc.rust-lang.org/std/primitive.s

Sure. In Rust there's a function called [`str::repeat`](https://doc.rust-lang.org/std/primitive.str.html#method.repeat https://doc.rust-lang.org/std/primitive.str.html#method.repe...) that takes a string slice and repeats it a number of times, allocating a new String in the process. Do there exist inputs -- either string or repetitions -- for which the following function does not panic owing to allocation issues (as documented) but either 1. cause a SIGBART or similar to be thrown or 2. fail to produce a new string which is the correct multiple size of the original string slice? It's not possible, I contend, to answer this question with tests. The cardinality of input strings and repetitions is bounded but very, very high. You can for sure find _examples_ where `str::repeat` functions as documented but demonstrating that it always will is a different thing.