unittest.sh: add support for on-device testing

This allows running unit tests on an ESP32 device connected to the USB serial port.
It uses mpremote.py for this.

tests/unittest.sh

@@ -6,6 +6,7 @@ testdir="$mydir"
 scriptdir=$(readlink -f "$mydir"/../scripts/)
 fs="$mydir"/../internal_filesystem/
 onetest="$1"
+ondevice="$2"
 
 
 # print os and set binary
@@ -26,10 +27,25 @@ one_test() {
 	file="$1"
 	pushd "$fs"
 	echo "Testing $file"
-	"$binary" -X heapsize=8M -c "import sys ; sys.path.append('lib') 
+	if [ -z "$ondevice" ]; then
+		"$binary" -X heapsize=8M -c "import sys ; sys.path.append('lib')
 $(cat $file)
 result = unittest.main() ; sys.exit(0 if result.wasSuccessful() else 1) "
-	result=$?
+		result=$?
+	else
+		cleanname=$(echo "$file" | sed "s#/#_#g")
+		testlog=/tmp/"$cleanname".log
+		mpremote.py exec "import sys ; sys.path.append('lib')
+$(cat $file)
+result = unittest.main()
+if result.wasSuccessful():
+    print('TEST WAS A SUCCESS')
+else:
+    print('TEST WAS A FAILURE')
+" > "$testlog"
+		grep "TEST WAS A SUCCESS" "$testlog"
+		result=$?
+	fi
 	popd
 	return "$result"
 }
@@ -37,10 +53,13 @@ result = unittest.main() ; sys.exit(0 if result.wasSuccessful() else 1) "
 failed=0
 
 if [ -z "$onetest" ]; then
-	echo "Usage: $0 [one_test_to_run.py]"
+	echo "Usage: $0 [one_test_to_run.py] [ondevice]"
 	echo "Example: $0 tests/simple.py"
+	echo "Example: $0 tests/simple.py ondevice"
 	echo
-	echo "If no test is specified: run all tests from $testdir"
+	echo "If no test is specified: run all tests from $testdir on local machine."
+	echo
+	echo "The 'ondevice' argument will try to run the test on a connected device using mpremote.py (should be on the PATH) over a serial connection."
 	while read file; do
 		one_test "$file"
 		result=$?