Warnings from cyclocomp_linter

[MichaelChirico]

As part of #653, I ran lintr::lint_package():

lintr::lint_package()

A ton of warnings were thrown:

#Warning messages:
#1: In parent == parent[before_operator_idx] :
#   longer object length is not a multiple of shorter object length
# ...
#653 50: In parent == parent[before_operator_idx] :
#  longer object length is not a multiple of shorter object length

At a glance, I suspect that cyclocomp_linter is getting tripped up by the with() expression:

with(
  source_file$parsed_content,
  token == "expr" & parent == parent[before_operator_idx]
)

But needs more investigation

[AshesITR]

Apparently before_operator_idx can have more than one TRUE entry.
At first glance, == should be %in% to fix the warnings.