tests/test-fuzz-targets.t

tests: unset environment variable P in test-revset2.t (issue6109)

The test tests/test-revset2.t fails the test case

"Test repo.anyrevs with customized revset overrides" (line 1609)

if the environment variable P is set. The test implicitly expects that the
environment, in which it is started, does not export the variable 'P'.

To solve this issue, unset 'P' right before the test commands are run.

Differential Revision: https://phab.mercurial-scm.org/D6195

#require test-repo

  $ cd $TESTDIR/../contrib/fuzz

which(1) could exit nonzero, but that's fine because we'll still end
up without a valid executable, so we don't need to check $? here.

  $ if which gmake >/dev/null 2>&1; then
  >     MAKE=gmake
  > else
  >     MAKE=make
  > fi

  $ havefuzz() {
  >     cat > $TESTTMP/dummy.cc <<EOF
  > #include <stdlib.h>
  > #include <stdint.h>
  > int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) { return 0; }
  > int main(int argc, char **argv) {
  >     const char data[] = "asdf";
  >     return LLVMFuzzerTestOneInput((const uint8_t *)data, 4);
  > }
  > EOF
  >     $CXX $TESTTMP/dummy.cc -o $TESTTMP/dummy \
  >        -fsanitize=fuzzer-no-link,address || return 1
  > }

#if clang-libfuzzer
  $ CXX=clang++ havefuzz || exit 80
  $ $MAKE -s clean all
#endif
#if no-clang-libfuzzer clang-6.0
  $ CXX=clang++-6.0 havefuzz || exit 80
  $ $MAKE -s clean all CC=clang-6.0 CXX=clang++-6.0
#endif
#if no-clang-libfuzzer no-clang-6.0
  $ exit 80
#endif

Just run the fuzzers for five seconds each to verify it works at all.
  $ ./bdiff -max_total_time 5
  $ ./mpatch -max_total_time 5
  $ ./xdiff -max_total_time 5