Issue2418

This is most likely truncation of the command line passed to the sub-process. The subprocess resource must be enable in regrtest to evoke the relevant test cases.

>dist\bin\jython -m test.regrtest -u subprocess -v test_chdir
test_chdir
 ... 
test_popen (test.test_chdir.SubprocessTestCase) ...   File "<string>", line 1
    import
         ^
SyntaxError: mismatched input '\n\n' expecting NAME
ERROR
test_subprocess (test.test_chdir.SubprocessTestCase) ...   File "<string>", line 1
    import
         ^
SyntaxError: mismatched input '\n\n' expecting NAME
FAIL
test_system (test.test_chdir.SubprocessTestCase) ...   File "<string>", line 1
    import
         ^
SyntaxError: mismatched input '\n\n' expecting NAME
FAIL

...
----------------------------------------------------------------------
Ran 45 tests in 12.215s

FAILED (failures=2, errors=1)

The extra quotes added here:
https://hg.python.org/jython/file/tip/Lib/test/test_chdir.py#l444
are the problem, presumably since subprocess became more conformant on Windows.