Parrot: Fix test cases (#3425)

* Test would spuriously fail when emulating statx with stat due to loss of precision in times.
Fix test by using fixed formmatting strings.

* Fix mistake -- parrot refers to a function in parrot-test.sh
Don't use parrot_run executable directly.

* Fix test to compare actual and expected output of command.
Prior example was failing in a strange way on /bin/dash.

Author: dthain

parrot/test/TR_parrot_execve.sh

@@ -16,6 +16,7 @@ prepare()
 {
 	chirp_start local
 	cp ${exe} ${root}/hello
+	${root}/hello > expected.txt
 
 	echo "$hostport" > config.txt
 
@@ -29,7 +30,7 @@ run()
 
 	parrot --no-chirp-catalog --timeout=5 --work-dir="/chirp/${hostport}/" ./hello > output.txt
 
-	if [ "$(cat output.txt)" == "Hello, world!" ]
+	if diff output.txt expected.txt
 	then
 		return 0
 	else

parrot/test/TR_parrot_stat.sh

@@ -27,7 +27,7 @@ run()
 	set -e
 
 	stat --format "$FORMAT" $file $link 2>/dev/null > $expected
-	parrot_run -- stat --format "$FORMAT" $file $link > $from_parrot
+	parrot -- stat --format "$FORMAT" $file $link > $from_parrot
 
 	diff $expected $from_parrot