tests: use more POSIX shell features our test scripts

Since commit 'v1.12-36-g2d68fd9' of 2012-05-07, "configure: search a
sturdy POSIX shell to be used in the testsuite", the shell running
our test script is assured to be a POSIX-conforming shell, so we can
use the more modern and flexible idioms and features that we couldn't
use when we also aimed at compatibility with non-POSIX Bourne shells,
like Solaris /bin/sh.

* t/README: Suggest to use POSIX shell features liberally in test cases,
with possible exception of Makefile recipes and configure shell code.
* Several tests: Adjust to use more POSIX shell features; e.g., $(...)
rather than `...`, $((...)) rather than `expr ...`, "if ! CMD; then ..."
instead of "if CMD; then :; else ...", and so on.
In several places, when using the 'test' built-in, prefer '-eq' over
'=' for numeric comparisons, and prefer "grep -c PATTERN FILE" over
"grep PATTERN FILE | wc -l".
Throw in other low-hanging easy improvements and fixlets while we are
at it.
* t/ax/depcomp.sh, t/ax/tap-summary-aux.sh, t/ax/tap-functions.sh,
defs, defs-static.in: Likewise.

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

1 files changed, 5 insertions, 8 deletions

diff --git a/t/ext.sh b/t/ext.sh
index c62dbd3ac..8d1d23870 100755
--- a/t/ext.sh
+++ b/t/ext.sh
@@ -39,13 +39,10 @@ END
 $ACLOCAL
 $AUTOMAKE
 
-for ext in f for f90 f95 F F90 F95 r m mm upc
-do
-   # Some versions of the BSD shell wrongly exit when 'set -e' is active
-   # if the last command within a compound statement fails and is guarded
-   # by an && only.  So we play safe and use the following idiom, instead
-   # of the apparently simpler 'grep ... && Exit 1'.
-   if grep "^$ext\.o:" Makefile.in; then Exit 1; else :; fi
+for ext in f for f90 f95 F F90 F95 r m mm upc; do
    grep "^\.$ext\.o:" Makefile.in
+   grep "^$ext\.o:" Makefile.in && Exit 1
+   : For shells with busted 'set -e'.
 done
-Exit 0
+
+: