Have tests each create a separate tmpdir, and cd into it

tests/entrypoint.sh

@@ -15,31 +15,41 @@ done
 
 # cd into script's directory
 cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null
+root=$(pwd)
 
-tmp="$(mktemp --tmpdir -d isle-tests.XXXXXX)"
-trap 'rm -rf $tmp' EXIT
+TMPDIR="$(mktemp --tmpdir -d isle-tests.XXXXXX)"
+trap 'rm -rf $TMPDIR' EXIT
 
-export TMPDIR="$tmp"
+export TMPDIR
 echo "tmp dir is $TMPDIR"
 
-echo -e '\nrunning all tests...\n'
+test_files=$(
+    find . -type f -name '*.sh' \
+    | sed "s|^\./||" \
+    | grep -v entrypoint.sh \
+    | sort -n\
+)
 
-for file in $(find . -type f -name '*.sh' | grep -v entrypoint.sh | sort -n); do
+echo -e "number of tests: $(echo "$test_files" | wc -l)\n"
+for file in $test_files; do
     echo "$file"
 
-    [ -z "$VERBOSE" ] && output="$tmp/$file.log" || output=/dev/stdout
+    [ -z "$VERBOSE" ] && output="$TMPDIR/$file.log" || output=/dev/stdout
 
-    if ! $SHELL -e -x "$file" >"$output" 2>&1; then
+    tmp="$TMPDIR/$file.tmp"
+    mkdir -p "$tmp"
+
+    if ! (cd "$tmp" && TMPDIR="$tmp" $SHELL -e -x "$root/$file" >"$output" 2>&1); then
         echo "$file FAILED"
         if [ -z "$VERBOSE" ]; then
             echo "output of test is as follows"
             echo "------------------------------"
-            cat "$tmp/$file.log"
+            cat "$TMPDIR/$file.log"
             echo "------------------------------"
         fi
         exit 1
     fi
 done
 
-echo -e '\ntests succeeded!'
+echo -e '\nall tests succeeded!'