Improve test script performance, note issues with slow machines

src/tests/README.md

@@ -159,3 +159,9 @@ extension unavailable in BSD implementations
 It's fairly simple to test each of these scripts independently, but
 the entire chain is a bit prone to behaving oddly in hard-to-debug
 ways.  `set -x` is your friend here.
+
+The test scripts are a bit fragile about timeouts.  They will
+generally run correctly on an unloaded machine without the `make -j`
+flag.  Using `make -j` is obviously very convenient for development,
+and it works fine on faster machines, but I don't recommend it for
+automated testing.

src/tests/e2e-test-subrs

@@ -15,7 +15,7 @@ sleepf()
     (sleep .1 || sleep 1) > /dev/null 2>&1
 }
 
-seq()
+seq_function()
 {
     if [ $# -lt 1 -o $# -gt 3 ]; then
 	echo "bad args" >&2
@@ -36,13 +36,20 @@ seq()
     esac
     while :; do
 	printf '%d\n' $first
-	first=$(expr $first + $incr)
+	first=$(( first + incr ))
 	if [ $first -gt $last ]; then
 	    break
 	fi
     done
 }
 
+if ! seq 1 > /dev/null 2>&1; then
+    seq()
+    {
+	seq_function "$@"
+    }
+fi
+
 chr()
 {
     printf "\\$(printf %03o $1)"

src/tests/emulation-ascii-iso-8859.test

@@ -23,7 +23,9 @@ baseline()
 
     # ASCII, then ISO-8859-1.
     for char in $(seq 32 126) $(seq 160 255) ; do
-	printf '%02x %s ' $char "$(utf8cp $char)"
+	printf '%02x ' $char
+	utf8cp $char
+	printf ' '
     done
     printf '\n'
 }