tests: simpler workaround for shells losing the exit status in exit trap

Now that we can assume our tests are run by a decent POSIX shell, we
can simplify our workaround aimed at having the exit status propagated
correctly to the code in the exit trap.  Unfortunately, we cannot
dispense with such a workaround altogether, because it's still required
by some shells we need to support (at least Solaris 10 /bin/ksh and
/usr/xpg4/bin/sh).

For more information about the need of that workaround, see the entry
about 'trap' in the section "Limitations of Shell Builtins" in the
Autoconf manual:
<http://www.gnu.org/software/autoconf/manual/autoconf.html#trap>

The new workaround has been tested successfully with the following
shells:

  - Bash 4.1
  - Bash 3.2
  - Bash 3.0
  - Bash 2.05b
  - dash 0.5.5.1
  - dash 0.5.2
  - AT&T Ksh 93u (from official Debian package)
  - MirBSD Korn Shell 40.2 (from official Debian package)
  - Solaris 9, 10 and 11 /bin/ksh
  - Solaris 9, 10 and 11 /usr/xpg4/bin/sh
  - NetBSD 5.1 /bin/sh
  - NetBSD 5.1 /bin/ksh

* t/ax/test-init.sh (Exit): Rename ...
(_am_exit): ... like this.
(exit): New alias for '_am_exit'.  We cannot simply redefine 'exit'
as a shell function, because some shells (dash 0.5.5.1, Solaris 10
/bin/ksh and /usr/xpg4/bin/sh) do not allow it.
(_am_exit, trap): Add extra escaping for 'exit' calls, to ensure we
really invoke the 'exit' builtin and not our alias with the same
name.
* configure.ac: Check that the shell selected to run our testsuite
supports aliases named like shell builtins.
* t/REAMDE: Adjust.
* All tests: Adjust, by simply using 'exit' instead of 'Exit'.
* t/self-check-explicit-skips.sh: Adjust: the first usage of 'exit'
after it has been redefined as an alias must be on a new line w.r.t.
that where the alias is defined, in order for the redefinition to be
honored.
* syntax-checks.mk (sc_tests_Exit_not_exit): Delete.
(sc_tests_exit_not_Exit): New.
(syntax_check_rules): Adjust.
(sc_tests_automake_fails): Simplify the recipe a little.
* Several tests: Remove now useless spurious quoting once required
to placate the 'sc_tests_Exit_not_exit' maintainer check.
* gen-testsuite-part: Likewise.  Also, avoid uses of 'Exit' in the
generated scripts.

Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>

1 files changed, 13 insertions, 10 deletions

diff --git a/t/self-check-explicit-skips.sh b/t/self-check-explicit-skips.sh
index ffab44d81..95ed31329 100755
--- a/t/self-check-explicit-skips.sh
+++ b/t/self-check-explicit-skips.sh
@@ -19,7 +19,7 @@
 # an early exit due to some command exiting unexpectedly with status 77.
 
 am_create_testdir=no
-. ./defs || Exit 1
+. ./defs || exit 1
 
 set +e
 
@@ -30,26 +30,29 @@ AM_TESTS_REEXEC=no; export AM_TESTS_REEXEC
 # testsuite shell to ensure it supports "VAR=val shell_func" correctly.
 run_dummy_test ()
 {
-  env $2 $AM_TEST_RUNNER_SHELL -c "am_create_testdir=no; . ./defs; $1" \
-                                  dummy.sh
+  env $2 $AM_TEST_RUNNER_SHELL -c "
+    am_create_testdir=no
+    . ./defs
+    $1
+  " dummy.sh
 }
 
 run_dummy_test '(exit 77); exit 77'
-test $? -eq 77 || Exit 1
+test $? -eq 77 || exit 1
 
 run_dummy_test 'sh -c "exit 77"' am_explicit_skips=no
-test $? -eq 77 || Exit 1
+test $? -eq 77 || exit 1
 
 run_dummy_test '(exit 77); exit 77' am_explicit_skips=yes 
-test $? -eq 78 || Exit 1
+test $? -eq 78 || exit 1
 
 run_dummy_test 'sh -c "exit 77"' am_explicit_skips=y
-test $? -eq 78 || Exit 1
+test $? -eq 78 || exit 1
 
-run_dummy_test 'Exit 77' am_explicit_skips=yes
-test $? -eq 77 || Exit 1
+run_dummy_test 'exit 77' am_explicit_skips=yes
+test $? -eq 77 || exit 1
 
 run_dummy_test 'skip_ "foo"' am_explicit_skips=y
-test $? -eq 77 || Exit 1
+test $? -eq 77 || exit 1
 
 :