Experimental
A function used to compute the location of the snapshot file.
The function receives the path of the test file as its only argument. If the
test is not associated with a file (for example in the REPL), the input is
undefined. fn()
must return a string specifying the location of the snapshot file.
This function is used to set a custom resolver for the location of the snapshot file used for snapshot testing. By default, the snapshot filename is the same as the entry point filename with
.snapshot
appended.