adding unit tests to the fix

CHANGES.txt

@@ -8,6 +8,9 @@ NOTE: The 4.0.0 Release of SCons dropped Python 2.7 Support
 NOTE: 4.3.0 now requires Python 3.6.0 and above. Python 3.5.x is no longer supported
 
 RELEASE  VERSION/DATE TO BE FILLED IN LATER
+  From Sten Grüner:
+    - Fix of --debug=sconscript option to return exist statements when using return
+      statement with stop flag enabled
 
   From Michał Górny:
     - Remove unecessary dependencies on pypi packages from setup.cfg

test/option/debug-sconscript.py

@@ -51,6 +51,18 @@
     'scons: Exiting %s%sSConstruct' % (wpath, os.sep)
 ]
 test.must_contain_all_lines(test.stdout(), expect)
+
+# Ensure that reutrns with stop are handled properly
+
+test.write('SConstruct', """\
+foo = "bar"
+Return("foo", stop=True)
+print("SConstruct")
+""")
+
+test.run(arguments="--debug=sconscript .")
+test.must_contain_all_lines(test.stdout(), expect)
+
 test.pass_test()
 
 # Local Variables: