QML JavaScript debugging does not step over to the last line in a function

step 1: Create a a Qt Quick project, add calling a JavaScript function while clicked a button, just like this:
function test

step 2: Place breakpoints for each line in the function test, then debug this program.
step 3: Debugger hit the first line when clicked the button.
step 4: Click "Step Over" or "Continue" once, debugger hit the second line in test.
step 5: Click "Step Over" or "Continue" again, debugger break the test but not hit the last line.