refactor: issue2551289. invalid REST Accept header stops request Sending a POST, PUT (maybe PATCH) with an accept header that is not application/json or xml (if enabled) used to complete the request before throwing a 406 error. This was wrong. Now it reports an error without dispatching/processing the requested transaction. This is the first of a series of refactors of the dispatch method to make it faster and more readable by using return early pattern and extracting methods from the code. changes: The following now return 406 errors not 400 errors invalid version specified with @apiver in URL. invalid version specified with @apiver in payload body invalid version specified in accept headers as application/vnd.roundup.test-vz+json or version property Parsing the accept header returns a 400 when presented with a parameter without an = sign or other parse error. They used to return a 406 which is wrong since the header is malformed rather than having a value I can't respond to. Some error messages were made clearer. Results in the case of an error are proper json error object rather than text/plain strings. New test added for testdetermine_output_formatBadAccept that test the new method using the same test cases as for testDispatchBadAccept. I intend to extend the test coverage for determine_output_format to cover more cases. This should be a faster unit test than for dispatch. Removed .lower() calls for accept_mime_type as the input values are taken from the values in the __accepted_content_type dict which only has lower case values.

"""
In Python 3, sometimes TAL "python:" expressions that refer to
variables but not all variables are recognized. That is in Python 2.7
all variables used in a TAL "python:" expression are recognized as
references. In Python 3.5 (perhaps earlier), some TAL "python:"
expressions refer to variables but the reference generates an error
like this:

<class 'NameError'>: name 'some_tal_variable' is not defined

even when the variable is defined. Output after this message lists the
variable and its value.
"""

import unittest

from roundup.cgi.PageTemplates.PythonExpr import PythonExpr as PythonExprClass

class ExprTest(unittest.TestCase):
    def testExpr(self):
        expr = '[x for x in context.assignedto ' \
               'if x.realname not in user_realnames]'
        pe = PythonExprClass('test', expr, None)
        # Looking at the expression, only context and user_realnames are
        # external variables. The names assignedto and realname are members,
        # and x is local.
        required_names = ['context', 'user_realnames']
        got_names = pe._f_varnames
        for required_name in required_names:
            self.assertIn(required_name, got_names)