[bug-patch] patch 2.7.1 tests fail when $(SHELL) is not bash or bash-like

[Harald van Dijk]

Hi,

patch 2.7.1 appears to build fine here, but several tests report bogus
errors due to nonportable shell script constructs in the testsuite.
These may also have been present in older versions, but I have only
tested 2.7.1. On my system, /bin/sh is dash, and that is what runs the
tests. Firstly, a major problem:

--- patch-2.7.1/tests/test-lib.sh
+++ patch-2.7.1/tests/test-lib.sh
@@ -118,7 +118,7 @@
 }
 
 if test -z "`echo -n`"; then
-    if eval 'test -n "${BASH_LINENO[0]}" 2>/dev/null'; then
+    if (eval 'test -n "${BASH_LINENO[0]}"') 2>/dev/null; then
     eval '
         _start_test() {
         echo -n "[${BASH_LINENO[2]}] $* -- "

This needs to run in a subshell to prevent it from terminating the
currently executing shell. dash reports a syntax error on
${BASH_LINENO[0]} and just exits, and no tests run at all.

Secondly, echo -e is nonportable (see `man 1p echo` on most Linux
systems), and doesn't behave on dash as it does on bash, causing a test
failure in crlf-handling.

--- patch-2.7.1/tests/crlf-handling
+++ patch-2.7.1/tests/crlf-handling
@@ -14,7 +14,7 @@
 use_tmpdir
 
 lf2crlf() {
-    while read l; do echo -e "$l\r"; done
+    while read l; do printf "%s\r\n" "$l"; done
 }
 
 echo 1 > a

printf is valid POSIX sh, which is what I've replaced it with, but I
don't know how portable it is to not-quite-POSIX shells that you may
wish to support.

Thirdly, test a == b is specific to bash, the standard syntax is test a
= b. Fourthly, shift may report an error when shifting more than the
remaining arguments (bash -c 'set --; shift' reports no error, dash -c
'set --; shift' reports "dash: 1: shift: can't shift that many"). These
both appear in tests/merge:

--- patch-2.7.1/tests/merge
+++ patch-2.7.1/tests/merge
@@ -32,18 +32,20 @@
     shift
     done > a.sed
     echo "$body" | sed -f a.sed > b
-    shift
-    while test $# -gt 0 ; do
-    echo "$1"
+    if test $# -gt 0 ; then
     shift
-    done > b.sed
+    while test $# -gt 0 ; do
+        echo "$1"
+        shift
+    done
+    fi > b.sed
     echo "$body" | sed -f b.sed > c
     rm -f a.sed b.sed
     output=`diff -u a b | patch $ARGS -f c`
     status=$?
     echo "$output" | sed -e '/^$/d' -e '/^patching file c$/d'
     cat c
-    test $status == 0 || echo "Status: $status"
+    test $status = 0 || echo "Status: $status"
 }
 
 x() {

The change for shift could alternatively be solved by making sure
there's always at least one argument (the "--"), if you like.

With those changes in the testsuite, all tests pass, so patch does
appear to be running correctly.

Cheers,
Harald