# Mutants that NO test can kill, with the reason each one is unreachable by any
# test that could be written.
#
# THE BAR IS IMPOSSIBILITY, NOT COST. A mutant that a test could kill, where
# nobody has written that test, does not belong here however unappealing the
# test looks. It stays a visible survivor with a GoingsOn task against it. The
# two classes are easy to conflate and the difference is the whole value of the
# number: an exclusion list that also absorbs "not worth it" reports zero while
# real coverage gaps sit underneath it.
#
# The evidence for that bar is in the sibling files. Of docengine's nine
# survivors, four were coverage gaps; of custom-pages' six, five looked
# equivalent at a glance and were not. So: try to kill it first, and add an
# entry only with the reason written out.
#
# The patterns are regexes, so `+`, `*` and `|` need escaping. A bare `||` is an
# empty alternation and silently excludes every mutant in the crate.

exclude_re = [
    # The two oracle wrappers in `mod oracle`. An oracle asserts what must hold
    # independently of the code under test, so it only speaks when that code is
    # wrong; replacing its body with `()` is invisible to every test that passes.
    # Killing it would mean shipping a broken planner for a test to catch, which
    # is not a test that can exist alongside a correct one.
    #
    # The evidence these two work is the other half of the same run rather than
    # a mutant: all 34 mutants in `MultipartPlan::{new,auto,part_len,part_range}`
    # were caught, and they were caught AT THESE ASSERTIONS.
    "replace oracle::check_plan with \\(\\)",
    "replace oracle::check_auto with \\(\\)",
]