tests/micropython: Add tests for micropython.schedule().

tests/micropython/schedule.py

+# test micropython.schedule() function
+
+import micropython
+
+try:
+    micropython.schedule
+except AttributeError:
+    print('SKIP')
+    import sys
+    sys.exit()
+
+# Basic test of scheduling a function.
+
+def callback(arg):
+    global done
+    print(arg)
+    done = True
+
+done = False
+micropython.schedule(callback, 1)
+while not done:
+    pass
+
+# Test that callbacks can be scheduled from within a callback, but
+# that they don't execute until the outer callback is finished.
+
+def callback_inner(arg):
+    global done
+    print('inner')
+    done += 1
+
+def callback_outer(arg):
+    global done
+    micropython.schedule(callback_inner, 0)
+    # need a loop so that the VM can check for pending events
+    for i in range(2):
+        pass
+    print('outer')
+    done += 1
+
+done = 0
+micropython.schedule(callback_outer, 0)
+while done != 2:
+    pass
+
+# Test that scheduling too many callbacks leads to an exception.  To do this we
+# must schedule from within a callback to guarantee that the scheduler is locked.
+
+def callback(arg):
+    global done
+    try:
+        for i in range(100):
+            micropython.schedule(lambda x:x, None)
+    except RuntimeError:
+        print('RuntimeError')
+    done = True
+
+done = False
+micropython.schedule(callback, None)
+while not done:
+    pass

tests/micropython/schedule.py.exp

+1
+outer
+inner
+RuntimeError

tests/run-tests

@@ -319,6 +319,7 @@ def run_tests(pyb, tests, args):
         skip_tests.add('misc/sys_exc_info.py') # sys.exc_info() is not supported for native
         skip_tests.add('micropython/heapalloc_traceback.py') # because native doesn't have proper traceback info
         skip_tests.add('micropython/heapalloc_iter.py') # requires generators
+        skip_tests.add('micropython/schedule.py') # native code doesn't check pending events
 
     for test_file in tests:
         test_file = test_file.replace('\\', '/')