Prepare some test for pytest in completers.

swap the context manager and the function definition.
It is undefined wither the test are collected and then run at once; or
ran while they are being yielded.

In the fist case (what pytest does) the function was called outside the
context manager, in the later case (node) it was working as expected.

IPython/core/tests/test_completer.py

@@ -1,1050 +1,1051 b''
 # encoding: utf-8
 """Tests for the IPython tab-completion machinery."""
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 import os
 import sys
 import textwrap
 import unittest
 
 from contextlib import contextmanager
 
 import nose.tools as nt
 
 from traitlets.config.loader import Config
 from IPython import get_ipython
 from IPython.core import completer
 from IPython.external import decorators
 from IPython.utils.tempdir import TemporaryDirectory, TemporaryWorkingDirectory
 from IPython.utils.generics import complete_object
 from IPython.testing import decorators as dec
 
 from IPython.core.completer import (
     Completion, provisionalcompleter, match_dict_keys, _deduplicate_completions)
 from nose.tools import assert_in, assert_not_in
 
 #-----------------------------------------------------------------------------
 # Test functions
 #-----------------------------------------------------------------------------
 
 @contextmanager
 def greedy_completion():
     ip = get_ipython()
     greedy_original = ip.Completer.greedy
     try:
         ip.Completer.greedy = True
         yield
     finally:
         ip.Completer.greedy = greedy_original
 
 def test_protect_filename():
     if sys.platform == 'win32':
         pairs = [('abc','abc'),
                  (' abc','" abc"'),
                  ('a bc','"a bc"'),
                  ('a  bc','"a  bc"'),
                  ('  bc','"  bc"'),
                  ]
     else:
         pairs = [('abc','abc'),
                  (' abc',r'\ abc'),
                  ('a bc',r'a\ bc'),
                  ('a  bc',r'a\ \ bc'),
                  ('  bc',r'\ \ bc'),
                  # On posix, we also protect parens and other special characters.
                  ('a(bc',r'a\(bc'),
                  ('a)bc',r'a\)bc'),
                  ('a( )bc',r'a\(\ \)bc'),
                  ('a[1]bc', r'a\[1\]bc'),
                  ('a{1}bc', r'a\{1\}bc'),
                  ('a#bc', r'a\#bc'),
                  ('a?bc', r'a\?bc'),
                  ('a=bc', r'a\=bc'),
                  ('a\\bc', r'a\\bc'),
                  ('a|bc', r'a\|bc'),
                  ('a;bc', r'a\;bc'),
                  ('a:bc', r'a\:bc'),
                  ("a'bc", r"a\'bc"),
                  ('a*bc', r'a\*bc'),
                  ('a"bc', r'a\"bc'),
                  ('a^bc', r'a\^bc'),
                  ('a&bc', r'a\&bc'),
                  ]
     # run the actual tests
     for s1, s2 in pairs:
         s1p = completer.protect_filename(s1)
         nt.assert_equal(s1p, s2)
 
 
 def check_line_split(splitter, test_specs):
     for part1, part2, split in test_specs:
         cursor_pos = len(part1)
         line = part1+part2
         out = splitter.split_line(line, cursor_pos)
         nt.assert_equal(out, split)
 
 
 def test_line_split():
     """Basic line splitter test with default specs."""
     sp = completer.CompletionSplitter()
     # The format of the test specs is: part1, part2, expected answer.  Parts 1
     # and 2 are joined into the 'line' sent to the splitter, as if the cursor
     # was at the end of part1.  So an empty part2 represents someone hitting
     # tab at the end of the line, the most common case.
     t = [('run some/scrip', '', 'some/scrip'),
          ('run scripts/er', 'ror.py foo', 'scripts/er'),
          ('echo $HOM', '', 'HOM'),
          ('print sys.pa', '', 'sys.pa'),
          ('print(sys.pa', '', 'sys.pa'),
          ("execfile('scripts/er", '', 'scripts/er'),
          ('a[x.', '', 'x.'),
          ('a[x.', 'y', 'x.'),
          ('cd "some_file/', '', 'some_file/'),
          ]
     check_line_split(sp, t)
     # Ensure splitting works OK with unicode by re-running the tests with
     # all inputs turned into unicode
     check_line_split(sp, [ map(str, p) for p in t] )
 
 
 def test_custom_completion_error():
     """Test that errors from custom attribute completers are silenced."""
     ip = get_ipython()
     class A(object): pass
     ip.user_ns['a'] = A()
     
     @complete_object.register(A)
     def complete_A(a, existing_completions):
         raise TypeError("this should be silenced")
     
     ip.complete("a.")
 
 
 def test_unicode_completions():
     ip = get_ipython()
     # Some strings that trigger different types of completion.  Check them both
     # in str and unicode forms
     s = ['ru', '%ru', 'cd /', 'floa', 'float(x)/']
     for t in s + list(map(str, s)):
         # We don't need to check exact completion values (they may change
         # depending on the state of the namespace, but at least no exceptions
         # should be thrown and the return value should be a pair of text, list
         # values.
         text, matches = ip.complete(t)
         nt.assert_true(isinstance(text, str))
         nt.assert_true(isinstance(matches, list))
 
 def test_latex_completions():
     from IPython.core.latex_symbols import latex_symbols
     import random
     ip = get_ipython()
     # Test some random unicode symbols
     keys = random.sample(latex_symbols.keys(), 10)
     for k in keys:
         text, matches = ip.complete(k)
         nt.assert_equal(len(matches),1)
         nt.assert_equal(text, k)
         nt.assert_equal(matches[0], latex_symbols[k])
     # Test a more complex line
     text, matches = ip.complete(u'print(\\alpha')
     nt.assert_equal(text, u'\\alpha')
     nt.assert_equal(matches[0], latex_symbols['\\alpha'])
     # Test multiple matching latex symbols
     text, matches = ip.complete(u'\\al')
     nt.assert_in('\\alpha', matches)
     nt.assert_in('\\aleph', matches)
 
 
 
 
 def test_back_latex_completion():
     ip = get_ipython()
 
     # do not return more than 1 matches fro \beta, only the latex one.
     name, matches = ip.complete('\\β')
     nt.assert_equal(len(matches), 1)
     nt.assert_equal(matches[0], '\\beta')
 
 def test_back_unicode_completion():
     ip = get_ipython()
     
     name, matches = ip.complete('\\Ⅴ')
     nt.assert_equal(len(matches), 1)
     nt.assert_equal(matches[0], '\\ROMAN NUMERAL FIVE')
 
 
 def test_forward_unicode_completion():
     ip = get_ipython()
     
     name, matches = ip.complete('\\ROMAN NUMERAL FIVE')
     nt.assert_equal(len(matches), 1)
     nt.assert_equal(matches[0], 'Ⅴ')
 
 @nt.nottest # now we have a completion for \jmath
 @decorators.knownfailureif(sys.platform == 'win32', 'Fails if there is a C:\\j... path')
 def test_no_ascii_back_completion():
     ip = get_ipython()
     with TemporaryWorkingDirectory():  # Avoid any filename completions
         # single ascii letter that don't have yet completions
         for letter in 'jJ' :
             name, matches = ip.complete('\\'+letter)
             nt.assert_equal(matches, [])
 
 
 
 
 class CompletionSplitterTestCase(unittest.TestCase):
     def setUp(self):
         self.sp = completer.CompletionSplitter()
 
     def test_delim_setting(self):
         self.sp.delims = ' '
         nt.assert_equal(self.sp.delims, ' ')
         nt.assert_equal(self.sp._delim_expr, r'[\ ]')
 
     def test_spaces(self):
         """Test with only spaces as split chars."""
         self.sp.delims = ' '
         t = [('foo', '', 'foo'),
              ('run foo', '', 'foo'),
              ('run foo', 'bar', 'foo'),
              ]
         check_line_split(self.sp, t)
 
 
 def test_has_open_quotes1():
     for s in ["'", "'''", "'hi' '"]:
         nt.assert_equal(completer.has_open_quotes(s), "'")
 
 
 def test_has_open_quotes2():
     for s in ['"', '"""', '"hi" "']:
         nt.assert_equal(completer.has_open_quotes(s), '"')
 
 
 def test_has_open_quotes3():
     for s in ["''", "''' '''", "'hi' 'ipython'"]:
         nt.assert_false(completer.has_open_quotes(s))
 
 
 def test_has_open_quotes4():
     for s in ['""', '""" """', '"hi" "ipython"']:
         nt.assert_false(completer.has_open_quotes(s))
 
 
 @decorators.knownfailureif(sys.platform == 'win32', "abspath completions fail on Windows")
 def test_abspath_file_completions():
     ip = get_ipython()
     with TemporaryDirectory() as tmpdir:
         prefix = os.path.join(tmpdir, 'foo')
         suffixes = ['1', '2']
         names = [prefix+s for s in suffixes]
         for n in names:
             open(n, 'w').close()
 
         # Check simple completion
         c = ip.complete(prefix)[1]
         nt.assert_equal(c, names)
 
         # Now check with a function call
         cmd = 'a = f("%s' % prefix
         c = ip.complete(prefix, cmd)[1]
         comp = [prefix+s for s in suffixes]
         nt.assert_equal(c, comp)
 
 
 def test_local_file_completions():
     ip = get_ipython()
     with TemporaryWorkingDirectory():
         prefix = './foo'
         suffixes = ['1', '2']
         names = [prefix+s for s in suffixes]
         for n in names:
             open(n, 'w').close()
 
         # Check simple completion
         c = ip.complete(prefix)[1]
         nt.assert_equal(c, names)
 
         # Now check with a function call
         cmd = 'a = f("%s' % prefix
         c = ip.complete(prefix, cmd)[1]
         comp = set(prefix+s for s in suffixes)
         nt.assert_true(comp.issubset(set(c)))
 
 
 def test_quoted_file_completions():
     ip = get_ipython()
     with TemporaryWorkingDirectory():
         name = "foo'bar"
         open(name, 'w').close()
 
         # Don't escape Windows
         escaped = name if sys.platform == "win32" else "foo\\'bar"
 
         # Single quote matches embedded single quote
         text = "open('foo"
         c = ip.Completer._complete(cursor_line=0,
                                    cursor_pos=len(text),
                                    full_text=text)[1]
         nt.assert_equal(c, [escaped])
 
         # Double quote requires no escape
         text = 'open("foo'
         c = ip.Completer._complete(cursor_line=0,
                                    cursor_pos=len(text),
                                    full_text=text)[1]
         nt.assert_equal(c, [name])
 
         # No quote requires an escape
         text = '%ls foo'
         c = ip.Completer._complete(cursor_line=0,
                                    cursor_pos=len(text),
                                    full_text=text)[1]
         nt.assert_equal(c, [escaped])
 
 
 def test_jedi():
     """
     A couple of issue we had with Jedi
     """
     ip = get_ipython()
 
     def _test_complete(reason, s, comp, start=None, end=None):
         l = len(s)
         start = start if start is not None else l
         end = end if end is not None else l
         with provisionalcompleter():
             ip.Completer.use_jedi = True
             completions = set(ip.Completer.completions(s, l))
             ip.Completer.use_jedi = False
             assert_in(Completion(start, end, comp), completions, reason)
 
     def _test_not_complete(reason, s, comp):
         l = len(s)
         with provisionalcompleter():
             ip.Completer.use_jedi = True
             completions = set(ip.Completer.completions(s, l))
             ip.Completer.use_jedi = False
             assert_not_in(Completion(l, l, comp), completions, reason)
 
     import jedi
     jedi_version = tuple(int(i) for i in jedi.__version__.split('.')[:3])
     if jedi_version > (0, 10):
         yield _test_complete, 'jedi >0.9 should complete and not crash', 'a=1;a.', 'real'
     yield _test_complete, 'can infer first argument', 'a=(1,"foo");a[0].', 'real'
     yield _test_complete, 'can infer second argument', 'a=(1,"foo");a[1].', 'capitalize'
     yield _test_complete, 'cover duplicate completions', 'im', 'import', 0, 2
 
     yield _test_not_complete, 'does not mix types', 'a=(1,"foo");a[0].', 'capitalize'
 
 def test_completion_have_signature():
     """
     Lets make sure jedi is capable of pulling out the signature of the function we are completing.
     """
     ip = get_ipython()
     with provisionalcompleter():
         ip.Completer.use_jedi = True
         completions = ip.Completer.completions('ope', 3)
         c = next(completions)  # should be `open`
         ip.Completer.use_jedi = False
     assert 'file' in c.signature, "Signature of function was not found by completer"
     assert 'encoding' in c.signature, "Signature of function was not found by completer"
 
 
 def test_deduplicate_completions():
     """
     Test that completions are correctly deduplicated (even if ranges are not the same)
     """
     ip = get_ipython()
     ip.ex(textwrap.dedent('''
     class Z:
         zoo = 1
     '''))
     with provisionalcompleter():
         ip.Completer.use_jedi = True
         l = list(_deduplicate_completions('Z.z', ip.Completer.completions('Z.z', 3)))
         ip.Completer.use_jedi = False
 
     assert len(l) == 1, 'Completions (Z.z<tab>) correctly deduplicate: %s ' % l
     assert l[0].text == 'zoo'  # and not `it.accumulate`
 
 
 def test_greedy_completions():
     """
     Test the capability of the Greedy completer. 
 
     Most of the test here does not really show off the greedy completer, for proof
     each of the text below now pass with Jedi. The greedy completer is capable of more. 
 
     See the :any:`test_dict_key_completion_contexts`
 
     """
     ip = get_ipython()
     ip.ex('a=list(range(5))')
     _,c = ip.complete('.',line='a[0].')
     nt.assert_false('.real' in c,
                     "Shouldn't have completed on a[0]: %s"%c)
-    with greedy_completion(), provisionalcompleter():
-        def _(line, cursor_pos, expect, message, completion):
+    def _(line, cursor_pos, expect, message, completion):
+        with greedy_completion(), provisionalcompleter():
             ip.Completer.use_jedi = False
             _,c = ip.complete('.', line=line, cursor_pos=cursor_pos)
             nt.assert_in(expect, c, message % c)
 
             ip.Completer.use_jedi = True
             with provisionalcompleter():
                 completions = ip.Completer.completions(line, cursor_pos)
             nt.assert_in(completion, completions)
 
+    with provisionalcompleter():
         yield _, 'a[0].', 5, 'a[0].real', "Should have completed on a[0].: %s", Completion(5,5, 'real')
         yield _, 'a[0].r', 6, 'a[0].real', "Should have completed on a[0].r: %s", Completion(5,6, 'real')
 
         if sys.version_info > (3, 4):
             yield _, 'a[0].from_', 10, 'a[0].from_bytes', "Should have completed on a[0].from_: %s", Completion(5, 10, 'from_bytes')
 
 
 def test_omit__names():
     # also happens to test IPCompleter as a configurable
     ip = get_ipython()
     ip._hidden_attr = 1
     ip._x = {}
     c = ip.Completer
     ip.ex('ip=get_ipython()')
     cfg = Config()
     cfg.IPCompleter.omit__names = 0
     c.update_config(cfg)
     with provisionalcompleter():
         c.use_jedi = False
         s,matches = c.complete('ip.')
         nt.assert_in('ip.__str__', matches)
         nt.assert_in('ip._hidden_attr', matches)
 
         # c.use_jedi = True
         # completions = set(c.completions('ip.', 3))
         # nt.assert_in(Completion(3, 3, '__str__'), completions)
         # nt.assert_in(Completion(3,3, "_hidden_attr"), completions)
 
 
     cfg = Config()
     cfg.IPCompleter.omit__names = 1
     c.update_config(cfg)
     with provisionalcompleter():
         c.use_jedi = False
         s,matches = c.complete('ip.')
         nt.assert_not_in('ip.__str__', matches)
         # nt.assert_in('ip._hidden_attr', matches)
 
         # c.use_jedi = True
         # completions = set(c.completions('ip.', 3))
         # nt.assert_not_in(Completion(3,3,'__str__'), completions)
         # nt.assert_in(Completion(3,3, "_hidden_attr"), completions)
 
     cfg = Config()
     cfg.IPCompleter.omit__names = 2
     c.update_config(cfg)
     with provisionalcompleter():
         c.use_jedi = False
         s,matches = c.complete('ip.')
         nt.assert_not_in('ip.__str__', matches)
         nt.assert_not_in('ip._hidden_attr', matches)
 
         # c.use_jedi = True
         # completions = set(c.completions('ip.', 3))
         # nt.assert_not_in(Completion(3,3,'__str__'), completions)
         # nt.assert_not_in(Completion(3,3, "_hidden_attr"), completions)
 
     with provisionalcompleter():
         c.use_jedi = False
         s,matches = c.complete('ip._x.')
         nt.assert_in('ip._x.keys', matches)
 
         # c.use_jedi = True
         # completions = set(c.completions('ip._x.', 6))
         # nt.assert_in(Completion(6,6, "keys"), completions)
 
     del ip._hidden_attr
     del ip._x
 
 
 def test_limit_to__all__False_ok():
     """
     Limit to all is deprecated, once we remove it this test can go away. 
     """
     ip = get_ipython()
     c = ip.Completer
     c.use_jedi = False
     ip.ex('class D: x=24')
     ip.ex('d=D()')
     cfg = Config()
     cfg.IPCompleter.limit_to__all__ = False
     c.update_config(cfg)
     s, matches = c.complete('d.')
     nt.assert_in('d.x', matches)
 
 
 def test_get__all__entries_ok():
     class A(object):
         __all__ = ['x', 1]
     words = completer.get__all__entries(A())
     nt.assert_equal(words, ['x'])
 
 
 def test_get__all__entries_no__all__ok():
     class A(object):
         pass
     words = completer.get__all__entries(A())
     nt.assert_equal(words, [])
 
 
 def test_func_kw_completions():
     ip = get_ipython()
     c = ip.Completer
     c.use_jedi = False
     ip.ex('def myfunc(a=1,b=2): return a+b')
     s, matches = c.complete(None, 'myfunc(1,b')
     nt.assert_in('b=', matches)
     # Simulate completing with cursor right after b (pos==10):
     s, matches = c.complete(None, 'myfunc(1,b)', 10)
     nt.assert_in('b=', matches)
     s, matches = c.complete(None, 'myfunc(a="escaped\\")string",b')
     nt.assert_in('b=', matches)
     #builtin function
     s, matches = c.complete(None, 'min(k, k')
     nt.assert_in('key=', matches)
 
 
 def test_default_arguments_from_docstring():
     ip = get_ipython()
     c = ip.Completer
     kwd = c._default_arguments_from_docstring(
         'min(iterable[, key=func]) -> value')
     nt.assert_equal(kwd, ['key'])
     #with cython type etc
     kwd = c._default_arguments_from_docstring(
         'Minuit.migrad(self, int ncall=10000, resume=True, int nsplit=1)\n')
     nt.assert_equal(kwd, ['ncall', 'resume', 'nsplit'])
     #white spaces
     kwd = c._default_arguments_from_docstring(
         '\n Minuit.migrad(self, int ncall=10000, resume=True, int nsplit=1)\n')
     nt.assert_equal(kwd, ['ncall', 'resume', 'nsplit'])
 
 def test_line_magics():
     ip = get_ipython()
     c = ip.Completer
     s, matches = c.complete(None, 'lsmag')
     nt.assert_in('%lsmagic', matches)
     s, matches = c.complete(None, '%lsmag')
     nt.assert_in('%lsmagic', matches)
 
 
 def test_cell_magics():
     from IPython.core.magic import register_cell_magic
 
     @register_cell_magic
     def _foo_cellm(line, cell):
         pass
     
     ip = get_ipython()
     c = ip.Completer
 
     s, matches = c.complete(None, '_foo_ce')
     nt.assert_in('%%_foo_cellm', matches)
     s, matches = c.complete(None, '%%_foo_ce')
     nt.assert_in('%%_foo_cellm', matches)
 
 
 def test_line_cell_magics():
     from IPython.core.magic import register_line_cell_magic
 
     @register_line_cell_magic
     def _bar_cellm(line, cell):
         pass
     
     ip = get_ipython()
     c = ip.Completer
 
     # The policy here is trickier, see comments in completion code.  The
     # returned values depend on whether the user passes %% or not explicitly,
     # and this will show a difference if the same name is both a line and cell
     # magic.
     s, matches = c.complete(None, '_bar_ce')
     nt.assert_in('%_bar_cellm', matches)
     nt.assert_in('%%_bar_cellm', matches)
     s, matches = c.complete(None, '%_bar_ce')
     nt.assert_in('%_bar_cellm', matches)
     nt.assert_in('%%_bar_cellm', matches)
     s, matches = c.complete(None, '%%_bar_ce')
     nt.assert_not_in('%_bar_cellm', matches)
     nt.assert_in('%%_bar_cellm', matches)
 
 
 def test_magic_completion_order():
     ip = get_ipython()
     c = ip.Completer
 
     # Test ordering of line and cell magics.
     text, matches = c.complete("timeit")
     nt.assert_equal(matches, ["%timeit", "%%timeit"])
 
 
 def test_magic_completion_shadowing():
     ip = get_ipython()
     c = ip.Completer
     c.use_jedi = False
 
     # Before importing matplotlib, %matplotlib magic should be the only option.
     text, matches = c.complete("mat")
     nt.assert_equal(matches, ["%matplotlib"])
 
     # The newly introduced name should shadow the magic.
     ip.run_cell("matplotlib = 1")
     text, matches = c.complete("mat")
     nt.assert_equal(matches, ["matplotlib"])
 
     # After removing matplotlib from namespace, the magic should again be
     # the only option.
     del ip.user_ns["matplotlib"]
     text, matches = c.complete("mat")
     nt.assert_equal(matches, ["%matplotlib"])
 
 def test_magic_completion_shadowing_explicit():
     """
     If the user try to complete a shadowed magic, and explicit % start should
     still return the completions.
     """
     ip = get_ipython()
     c = ip.Completer
 
     # Before importing matplotlib, %matplotlib magic should be the only option.
     text, matches = c.complete("%mat")
     nt.assert_equal(matches, ["%matplotlib"])
 
     ip.run_cell("matplotlib = 1")
 
     # After removing matplotlib from namespace, the magic should still be
     # the only option.
     text, matches = c.complete("%mat")
     nt.assert_equal(matches, ["%matplotlib"])
 
 def test_magic_config():
     ip = get_ipython()
     c = ip.Completer
 
     s, matches = c.complete(None, 'conf')
     nt.assert_in('%config', matches)
     s, matches = c.complete(None, 'conf')
     nt.assert_not_in('AliasManager', matches)
     s, matches = c.complete(None, 'config ')
     nt.assert_in('AliasManager', matches)
     s, matches = c.complete(None, '%config ')
     nt.assert_in('AliasManager', matches)
     s, matches = c.complete(None, 'config Ali')
     nt.assert_list_equal(['AliasManager'], matches)
     s, matches = c.complete(None, '%config Ali')
     nt.assert_list_equal(['AliasManager'], matches)
     s, matches = c.complete(None, 'config AliasManager')
     nt.assert_list_equal(['AliasManager'], matches)
     s, matches = c.complete(None, '%config AliasManager')
     nt.assert_list_equal(['AliasManager'], matches)
     s, matches = c.complete(None, 'config AliasManager.')
     nt.assert_in('AliasManager.default_aliases', matches)
     s, matches = c.complete(None, '%config AliasManager.')
     nt.assert_in('AliasManager.default_aliases', matches)
     s, matches = c.complete(None, 'config AliasManager.de')
     nt.assert_list_equal(['AliasManager.default_aliases'], matches)
     s, matches = c.complete(None, 'config AliasManager.de')
     nt.assert_list_equal(['AliasManager.default_aliases'], matches)
 
 
 def test_magic_color():
     ip = get_ipython()
     c = ip.Completer
 
     s, matches = c.complete(None, 'colo')
     nt.assert_in('%colors', matches)
     s, matches = c.complete(None, 'colo')
     nt.assert_not_in('NoColor', matches)
     s, matches = c.complete(None, '%colors')  # No trailing space
     nt.assert_not_in('NoColor', matches)
     s, matches = c.complete(None, 'colors ')
     nt.assert_in('NoColor', matches)
     s, matches = c.complete(None, '%colors ')
     nt.assert_in('NoColor', matches)
     s, matches = c.complete(None, 'colors NoCo')
     nt.assert_list_equal(['NoColor'], matches)
     s, matches = c.complete(None, '%colors NoCo')
     nt.assert_list_equal(['NoColor'], matches)
 
 
 def test_match_dict_keys():
     """
     Test that match_dict_keys works on a couple of use case does return what
     expected, and does not crash
     """
     delims = ' \t\n`!@#$^&*()=+[{]}\\|;:\'",<>?'
 
 
     keys = ['foo', b'far']
     assert match_dict_keys(keys, "b'", delims=delims)  == ("'", 2 ,['far'])
     assert match_dict_keys(keys, "b'f", delims=delims) == ("'", 2 ,['far'])
     assert match_dict_keys(keys, 'b"', delims=delims)  == ('"', 2 ,['far'])
     assert match_dict_keys(keys, 'b"f', delims=delims) == ('"', 2 ,['far'])
 
     assert match_dict_keys(keys, "'", delims=delims)  == ("'", 1 ,['foo'])
     assert match_dict_keys(keys, "'f", delims=delims) == ("'", 1 ,['foo'])
     assert match_dict_keys(keys, '"', delims=delims)  == ('"', 1 ,['foo'])
     assert match_dict_keys(keys, '"f', delims=delims) == ('"', 1 ,['foo'])
     
     match_dict_keys
 
 
 def test_dict_key_completion_string():
     """Test dictionary key completion for string keys"""
     ip = get_ipython()
     complete = ip.Completer.complete
 
     ip.user_ns['d'] = {'abc': None}
 
     # check completion at different stages
     _, matches = complete(line_buffer="d[")
     nt.assert_in("'abc'", matches)
     nt.assert_not_in("'abc']", matches)
 
     _, matches = complete(line_buffer="d['")
     nt.assert_in("abc", matches)
     nt.assert_not_in("abc']", matches)
 
     _, matches = complete(line_buffer="d['a")
     nt.assert_in("abc", matches)
     nt.assert_not_in("abc']", matches)
 
     # check use of different quoting
     _, matches = complete(line_buffer="d[\"")
     nt.assert_in("abc", matches)
     nt.assert_not_in('abc\"]', matches)
 
     _, matches = complete(line_buffer="d[\"a")
     nt.assert_in("abc", matches)
     nt.assert_not_in('abc\"]', matches)
 
     # check sensitivity to following context
     _, matches = complete(line_buffer="d[]", cursor_pos=2)
     nt.assert_in("'abc'", matches)
 
     _, matches = complete(line_buffer="d['']", cursor_pos=3)
     nt.assert_in("abc", matches)
     nt.assert_not_in("abc'", matches)
     nt.assert_not_in("abc']", matches)
 
     # check multiple solutions are correctly returned and that noise is not
     ip.user_ns['d'] = {'abc': None, 'abd': None, 'bad': None, object(): None,
                        5: None}
 
     _, matches = complete(line_buffer="d['a")
     nt.assert_in("abc", matches)
     nt.assert_in("abd", matches)
     nt.assert_not_in("bad", matches)
     assert not any(m.endswith((']', '"', "'")) for m in matches), matches
 
     # check escaping and whitespace
     ip.user_ns['d'] = {'a\nb': None, 'a\'b': None, 'a"b': None, 'a word': None}
     _, matches = complete(line_buffer="d['a")
     nt.assert_in("a\\nb", matches)
     nt.assert_in("a\\'b", matches)
     nt.assert_in("a\"b", matches)
     nt.assert_in("a word", matches)
     assert not any(m.endswith((']', '"', "'")) for m in matches), matches
 
     # - can complete on non-initial word of the string
     _, matches = complete(line_buffer="d['a w")
     nt.assert_in("word", matches)
 
     # - understands quote escaping
     _, matches = complete(line_buffer="d['a\\'")
     nt.assert_in("b", matches)
 
     # - default quoting should work like repr
     _, matches = complete(line_buffer="d[")
     nt.assert_in("\"a'b\"", matches)
 
     # - when opening quote with ", possible to match with unescaped apostrophe
     _, matches = complete(line_buffer="d[\"a'")
     nt.assert_in("b", matches)
 
     # need to not split at delims that readline won't split at
     if '-' not in ip.Completer.splitter.delims:
         ip.user_ns['d'] = {'before-after': None}
         _, matches = complete(line_buffer="d['before-af")
         nt.assert_in('before-after', matches)
 
 def test_dict_key_completion_contexts():
     """Test expression contexts in which dict key completion occurs"""
     ip = get_ipython()
     complete = ip.Completer.complete
     d = {'abc': None}
     ip.user_ns['d'] = d
 
     class C:
         data = d
     ip.user_ns['C'] = C
     ip.user_ns['get'] = lambda: d
 
     def assert_no_completion(**kwargs):
         _, matches = complete(**kwargs)
         nt.assert_not_in('abc', matches)
         nt.assert_not_in('abc\'', matches)
         nt.assert_not_in('abc\']', matches)
         nt.assert_not_in('\'abc\'', matches)
         nt.assert_not_in('\'abc\']', matches)
 
     def assert_completion(**kwargs):
         _, matches = complete(**kwargs)
         nt.assert_in("'abc'", matches)
         nt.assert_not_in("'abc']", matches)
 
     # no completion after string closed, even if reopened
     assert_no_completion(line_buffer="d['a'")
     assert_no_completion(line_buffer="d[\"a\"")
     assert_no_completion(line_buffer="d['a' + ")
     assert_no_completion(line_buffer="d['a' + '")
 
     # completion in non-trivial expressions
     assert_completion(line_buffer="+ d[")
     assert_completion(line_buffer="(d[")
     assert_completion(line_buffer="C.data[")
 
     # greedy flag
     def assert_completion(**kwargs):
         _, matches = complete(**kwargs)
         nt.assert_in("get()['abc']", matches)
     
     assert_no_completion(line_buffer="get()[")
     with greedy_completion():
         assert_completion(line_buffer="get()[")
         assert_completion(line_buffer="get()['")
         assert_completion(line_buffer="get()['a")
         assert_completion(line_buffer="get()['ab")
         assert_completion(line_buffer="get()['abc")
 
 
 
 def test_dict_key_completion_bytes():
     """Test handling of bytes in dict key completion"""
     ip = get_ipython()
     complete = ip.Completer.complete
 
     ip.user_ns['d'] = {'abc': None, b'abd': None}
 
     _, matches = complete(line_buffer="d[")
     nt.assert_in("'abc'", matches)
     nt.assert_in("b'abd'", matches)
 
     if False:  # not currently implemented
         _, matches = complete(line_buffer="d[b")
         nt.assert_in("b'abd'", matches)
         nt.assert_not_in("b'abc'", matches)
 
         _, matches = complete(line_buffer="d[b'")
         nt.assert_in("abd", matches)
         nt.assert_not_in("abc", matches)
 
         _, matches = complete(line_buffer="d[B'")
         nt.assert_in("abd", matches)
         nt.assert_not_in("abc", matches)
 
         _, matches = complete(line_buffer="d['")
         nt.assert_in("abc", matches)
         nt.assert_not_in("abd", matches)
 
 
 def test_dict_key_completion_unicode_py3():
     """Test handling of unicode in dict key completion"""
     ip = get_ipython()
     complete = ip.Completer.complete
 
     ip.user_ns['d'] = {u'a\u05d0': None}
 
     # query using escape
     if sys.platform != 'win32':
         # Known failure on Windows
         _, matches = complete(line_buffer="d['a\\u05d0")
         nt.assert_in("u05d0", matches)  # tokenized after \\
 
     # query using character
     _, matches = complete(line_buffer="d['a\u05d0")
     nt.assert_in(u"a\u05d0", matches)
     
     with greedy_completion():
         # query using escape
         _, matches = complete(line_buffer="d['a\\u05d0")
         nt.assert_in("d['a\\u05d0']", matches)  # tokenized after \\
 
         # query using character
         _, matches = complete(line_buffer="d['a\u05d0")
         nt.assert_in(u"d['a\u05d0']", matches)
         
 
 
 @dec.skip_without('numpy')
 def test_struct_array_key_completion():
     """Test dict key completion applies to numpy struct arrays"""
     import numpy
     ip = get_ipython()
     complete = ip.Completer.complete
     ip.user_ns['d'] = numpy.array([], dtype=[('hello', 'f'), ('world', 'f')])
     _, matches = complete(line_buffer="d['")
     nt.assert_in("hello", matches)
     nt.assert_in("world", matches)
     # complete on the numpy struct itself
     dt = numpy.dtype([('my_head', [('my_dt', '>u4'), ('my_df', '>u4')]),
                       ('my_data', '>f4', 5)])
     x = numpy.zeros(2, dtype=dt)
     ip.user_ns['d'] = x[1]
     _, matches = complete(line_buffer="d['")
     nt.assert_in("my_head", matches)
     nt.assert_in("my_data", matches)
     # complete on a nested level
     with greedy_completion():
         ip.user_ns['d'] = numpy.zeros(2, dtype=dt)
         _, matches = complete(line_buffer="d[1]['my_head']['")
         nt.assert_true(any(["my_dt" in m for m in matches]))
         nt.assert_true(any(["my_df" in m for m in matches]))
 
 
 @dec.skip_without('pandas')
 def test_dataframe_key_completion():
     """Test dict key completion applies to pandas DataFrames"""
     import pandas
     ip = get_ipython()
     complete = ip.Completer.complete
     ip.user_ns['d'] = pandas.DataFrame({'hello': [1], 'world': [2]})
     _, matches = complete(line_buffer="d['")
     nt.assert_in("hello", matches)
     nt.assert_in("world", matches)
 
 
 def test_dict_key_completion_invalids():
     """Smoke test cases dict key completion can't handle"""
     ip = get_ipython()
     complete = ip.Completer.complete
 
     ip.user_ns['no_getitem'] = None
     ip.user_ns['no_keys'] = []
     ip.user_ns['cant_call_keys'] = dict
     ip.user_ns['empty'] = {}
     ip.user_ns['d'] = {'abc': 5}
 
     _, matches = complete(line_buffer="no_getitem['")
     _, matches = complete(line_buffer="no_keys['")
     _, matches = complete(line_buffer="cant_call_keys['")
     _, matches = complete(line_buffer="empty['")
     _, matches = complete(line_buffer="name_error['")
     _, matches = complete(line_buffer="d['\\")  # incomplete escape
 
 class KeyCompletable(object):
     def __init__(self, things=()):
         self.things = things
 
     def _ipython_key_completions_(self):
         return list(self.things)
 
 def test_object_key_completion():
     ip = get_ipython()
     ip.user_ns['key_completable'] = KeyCompletable(['qwerty', 'qwick'])
 
     _, matches = ip.Completer.complete(line_buffer="key_completable['qw")
     nt.assert_in('qwerty', matches)
     nt.assert_in('qwick', matches)
 
 
 class NamedInstanceMetaclass(type):
     def __getitem__(cls, item):
         return cls.get_instance(item)
 
 class NamedInstanceClass(object, metaclass=NamedInstanceMetaclass):
     def __init__(self, name):
         if not hasattr(self.__class__, 'instances'):
             self.__class__.instances = {}
         self.__class__.instances[name] = self
 
     @classmethod
     def _ipython_key_completions_(cls):
         return cls.instances.keys()
 
     @classmethod
     def get_instance(cls, name):
         return cls.instances[name]
 
 def test_class_key_completion():
     ip = get_ipython()
     NamedInstanceClass('qwerty')
     NamedInstanceClass('qwick')
     ip.user_ns['named_instance_class'] = NamedInstanceClass
 
     _, matches = ip.Completer.complete(line_buffer="named_instance_class['qw")
     nt.assert_in('qwerty', matches)
     nt.assert_in('qwick', matches)
 
 def test_tryimport():
     """
     Test that try-import don't crash on trailing dot, and import modules before
     """
     from IPython.core.completerlib import try_import
     assert(try_import("IPython."))
 
 
 def test_aimport_module_completer():
     ip = get_ipython()
     _, matches = ip.complete('i', '%aimport i')
     nt.assert_in('io', matches)
     nt.assert_not_in('int', matches)
 
 def test_nested_import_module_completer():
     ip = get_ipython()
     _, matches = ip.complete(None, 'import IPython.co', 17)
     nt.assert_in('IPython.core', matches)
     nt.assert_not_in('import IPython.core', matches)
     nt.assert_not_in('IPython.display', matches)
 
 def test_import_module_completer():
     ip = get_ipython()
     _, matches = ip.complete('i', 'import i')
     nt.assert_in('io', matches)
     nt.assert_not_in('int', matches)
 
 def test_from_module_completer():
     ip = get_ipython()
     _, matches = ip.complete('B', 'from io import B', 16)
     nt.assert_in('BytesIO', matches)
     nt.assert_not_in('BaseException', matches)
 
 def test_snake_case_completion():
     ip = get_ipython()
     ip.Completer.use_jedi = False
     ip.user_ns['some_three'] = 3
     ip.user_ns['some_four'] = 4
     _, matches = ip.complete("s_", "print(s_f")
     nt.assert_in('some_three', matches)
     nt.assert_in('some_four', matches)
 
 def test_mix_terms():
     ip = get_ipython()
     from textwrap import dedent
     ip.Completer.use_jedi = False
     ip.ex(dedent("""
         class Test:
             def meth(self, meth_arg1):
                 print("meth")
 
             def meth_1(self, meth1_arg1, meth1_arg2):
                 print("meth1")
 
             def meth_2(self, meth2_arg1, meth2_arg2):
                 print("meth2")
         test = Test()
         """))
     _, matches = ip.complete(None, "test.meth(")
     nt.assert_in('meth_arg1=', matches)
     nt.assert_not_in('meth2_arg1=', matches)