test for autocall regression

Without the fix in  #14513, this test would fail with

>           assert ip.prefilter("foo") == "foo"
E           AssertionError: assert 'foo()' == 'foo'

IPython/core/tests/test_prefilter.py

@@ -1,139 +1,149
 """Tests for input manipulation machinery."""
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 import pytest
 
 from IPython.core.prefilter import AutocallChecker
 
 #-----------------------------------------------------------------------------
 # Tests
 #-----------------------------------------------------------------------------
 
 def test_prefilter():
     """Test user input conversions"""
 
     # pairs of (raw, expected correct) input
     pairs = [ ('2+2','2+2'),
              ]
 
     for raw, correct in pairs:
         assert ip.prefilter(raw) == correct
 
 def test_prefilter_shadowed():
     def dummy_magic(line): pass
 
     prev_automagic_state = ip.automagic
     ip.automagic = True
     ip.autocall = 0
 
     try:
         # These should not be transformed - they are shadowed by other names
         for name in ['if', 'zip', 'get_ipython']: # keyword, builtin, global
             ip.register_magic_function(dummy_magic, magic_name=name)
             res = ip.prefilter(name + " foo")
             assert res == name + " foo"
             del ip.magics_manager.magics["line"][name]
 
         # These should be transformed
         for name in ['fi', 'piz', 'nohtypi_teg']:
             ip.register_magic_function(dummy_magic, magic_name=name)
             res = ip.prefilter(name + " foo")
             assert res != name + " foo"
             del ip.magics_manager.magics["line"][name]
 
     finally:
         ip.automagic = prev_automagic_state
 
 def test_autocall_binops():
     """See https://github.com/ipython/ipython/issues/81"""
     ip.run_line_magic("autocall", "2")
     f = lambda x: x
     ip.user_ns['f'] = f
     try:
         assert ip.prefilter("f 1") == "f(1)"
         for t in ["f +1", "f -1"]:
             assert ip.prefilter(t) == t
 
         # Run tests again with a more permissive exclude_regexp, which will
         # allow transformation of binary operations ('f -1' -> 'f(-1)').
         pm = ip.prefilter_manager
         ac = AutocallChecker(shell=pm.shell, prefilter_manager=pm,
                              config=pm.config)
         try:
             ac.priority = 1
             ac.exclude_regexp = r'^[,&^\|\*/]|^is |^not |^in |^and |^or '
             pm.sort_checkers()
 
             assert ip.prefilter("f -1") == "f(-1)"
             assert ip.prefilter("f +1") == "f(+1)"
         finally:
             pm.unregister_checker(ac)
     finally:
         ip.run_line_magic("autocall", "0")
         del ip.user_ns["f"]
 
 
 def test_issue_114():
     """Check that multiline string literals don't expand as magic
     see http://github.com/ipython/ipython/issues/114"""
 
     template = '"""\n%s\n"""'
     # Store the current value of multi_line_specials and turn it off before
     # running test, since it could be true (case in which the test doesn't make
     # sense, as multiline string literals *will* expand as magic in that case).
     msp = ip.prefilter_manager.multi_line_specials
     ip.prefilter_manager.multi_line_specials = False
     try:
         for mgk in ip.magics_manager.lsmagic()['line']:
             raw = template % mgk
             assert ip.prefilter(raw) == raw
     finally:
         ip.prefilter_manager.multi_line_specials = msp
 
 
 def test_prefilter_attribute_errors():
     """Capture exceptions thrown by user objects on attribute access.
 
     See http://github.com/ipython/ipython/issues/988."""
 
     class X(object):
         def __getattr__(self, k):
             raise ValueError('broken object')
         def __call__(self, x):
             return x
 
     # Create a callable broken object
     ip.user_ns["x"] = X()
     ip.run_line_magic("autocall", "2")
     try:
         # Even if x throws an attribute error when looking at its rewrite
         # attribute, we should not crash.  So the test here is simply making
         # the prefilter call and not having an exception.
         ip.prefilter('x 1')
     finally:
         del ip.user_ns["x"]
         ip.run_line_magic("autocall", "0")
 
 
 def test_autocall_type_ann():
     ip.run_cell("import collections.abc")
     ip.run_line_magic("autocall", "1")
     try:
         assert (
             ip.prefilter("collections.abc.Callable[[int], None]")
             == "collections.abc.Callable[[int], None]"
         )
     finally:
         ip.run_line_magic("autocall", "0")
 
 
 def test_autocall_should_support_unicode():
     ip.run_line_magic("autocall", "2")
     ip.user_ns["π"] = lambda x: x
     try:
         assert ip.prefilter("π 3") == "π(3)"
     finally:
         ip.run_line_magic("autocall", "0")
         del ip.user_ns["π"]
+
+
+def test_autocall_regression_gh_14513():
+    ip.run_line_magic("autocall", "2")
+    ip.user_ns["foo"] = dict()
+    try:
+        assert ip.prefilter("foo") == "foo"
+    finally:
+        ip.run_line_magic("autocall", "0")
+        del ip.user_ns["foo"]