Ensure that we don't damage the __builtins__ object after %run.

This fixes lp:364853.

Also added a standalone set of testing.tools utilities that can be used in
place of nose.tools to get proper test generators in object oriented tests.

IPython/testing/tools.py

@@ -0,0 +1,88 b''
+"""Generic testing tools that do NOT depend on Twisted.
+
+In particular, this module exposes a set of top-level assert* functions that
+can be used in place of nose.tools.assert* in method generators (the ones in
+nose can not, at least as of nose 0.10.4).
+
+Note: our testing package contains testing.util, which does depend on Twisted
+and provides utilities for tests that manage Deferreds.  All testing support
+tools that only depend on nose, IPython or the standard library should go here
+instead.
+
+
+Authors
+-------
+- Fernando Perez <[e-mail]>
+"""
+
+#*****************************************************************************
+#       Copyright (C) 2009 The IPython Development Team
+#
+#  Distributed under the terms of the BSD License.  The full license is in
+#  the file COPYING, distributed as part of this software.
+#*****************************************************************************
+
+#-----------------------------------------------------------------------------
+# Required modules and packages
+#-----------------------------------------------------------------------------
+
+# Standard Python lib
+import os
+import sys
+
+# Third-party
+import nose.tools as nt
+
+# From this project
+from IPython.tools import utils
+
+#-----------------------------------------------------------------------------
+# Globals
+#-----------------------------------------------------------------------------
+
+# Make a bunch of nose.tools assert wrappers that can be used in test
+# generators.  This will expose an assert* function for each one in nose.tools.
+
+_tpl = """
+def %(name)s(*a,**kw):
+    return nt.%(name)s(*a,**kw)
+"""
+
+for _x in [a for a in dir(nt) if a.startswith('assert')]:
+    exec _tpl % dict(name=_x)
+
+#-----------------------------------------------------------------------------
+# Functions and classes
+#-----------------------------------------------------------------------------
+
+def full_path(startPath,files):
+    """Make full paths for all the listed files, based on startPath.
+
+    Only the base part of startPath is kept, since this routine is typically
+    used with a script's __file__ variable as startPath.  The base of startPath
+    is then prepended to all the listed files, forming the output list.
+
+    :Parameters:
+      startPath : string
+        Initial path to use as the base for the results.  This path is split
+      using os.path.split() and only its first component is kept.
+
+      files : string or list
+        One or more files.
+
+    :Examples:
+
+    >>> full_path('/foo/bar.py',['a.txt','b.txt'])
+    ['/foo/a.txt', '/foo/b.txt']
+
+    >>> full_path('/foo',['a.txt','b.txt'])
+    ['/a.txt', '/b.txt']
+
+    If a single file is given, the output is still a list:
+    >>> full_path('/foo','a.txt')
+    ['/a.txt']
+    """
+
+    files = utils.list_strings(files)
+    base = os.path.split(startPath)[0]
+    return [ os.path.join(base,f) for f in files ]

IPython/Magic.py

@@ -1709,6 +1709,16 b' Currently the magic system has the following functions:\\n"""'
                     del prog_ns['__name__']
                     self.shell.user_ns.update(prog_ns)
         finally:
+            # It's a bit of a mystery why, but __builtins__ can change from
+            # being a module to becoming a dict missing some key data after
+            # %run.  As best I can see, this is NOT something IPython is doing
+            # at all, and similar problems have been reported before:
+            # http://coding.derkeiler.com/Archive/Python/comp.lang.python/2004-10/0188.html
+            # Since this seems to be done by the interpreter itself, the best
+            # we can do is to at least restore __builtins__ for the user on
+            # exit.
+            self.shell.user_ns['__builtins__'] = __builtin__
+            
             # Ensure key global structures are restored
             sys.argv = save_argv
             if restore_main:

IPython/testing/plugin/ipdoctest.py

@@ -123,11 +123,20 b' class ipnsdict(dict):'
     def update(self,other):
         self._checkpoint()
         dict.update(self,other)
+
         # If '_' is in the namespace, python won't set it when executing code,
         # and we have examples that test it.  So we ensure that the namespace
         # is always 'clean' of it before it's used for test code execution.
         self.pop('_',None)
         
+        # The builtins namespace must *always* be the real __builtin__ module,
+        # else weird stuff happens.  The main ipython code does have provisions
+        # to ensure this after %run, but since in this class we do some
+        # aggressive low-level cleaning of the execution namespace, we need to
+        # correct for that ourselves, to ensure consitency with the 'real'
+        # ipython.
+        self['__builtins__'] = __builtin__
+        
 
 def start_ipython():
     """Start a global IPython shell, which we need for IPython-specific syntax.

IPython/testing/plugin/test_ipdoctest.py

@@ -18,6 +18,25 b' def doctest_simple():'
     """
 
 
+def doctest_run_builtins():
+    """Check that %run doesn't damage __builtins__ via a doctest.
+
+    This is similar to the test_run_builtins, but I want *both* forms of the
+    test to catch any possible glitches in our testing machinery, since that
+    modifies %run somewhat.  So for this, we have both a normal test (below)
+    and a doctest (this one).
+
+    In [1]: import tempfile
+
+    In [3]: f = tempfile.NamedTemporaryFile()
+
+    In [4]: f.write('pass\\n')
+
+    In [5]: f.flush()
+
+    In [7]: %run $f.name
+    """
+
 def doctest_multiline1():
     """The ipdoctest machinery must handle multiline examples gracefully.
 

IPython/tests/test_magic.py

@@ -6,12 +6,16 b' Needs to be run by nose (to make ipython session available).'
 # Standard library imports
 import os
 import sys
+import tempfile
+import types
 
 # Third-party imports
 import nose.tools as nt
 
 # From our own code
 from IPython.testing import decorators as dec
+from IPython.testing import tools as tt
+
 #-----------------------------------------------------------------------------
 # Test functions begin
 
@@ -33,26 +37,6 b' def test_rehashx():'
     assert len(scoms) > 10
 
 
-def doctest_run_ns():
-    """Classes declared %run scripts must be instantiable afterwards.
-
-    In [11]: run tclass foo
-
-    In [12]: isinstance(f(),foo)
-    Out[12]: True
-    """
-
-    
-def doctest_run_ns2():
-    """Classes declared %run scripts must be instantiable afterwards.
-
-    In [4]: run tclass C-first_pass
-
-    In [5]: run tclass C-second_pass
-    tclass.py: deleting object: C-first_pass
-    """
-
-
 def doctest_hist_f():
     """Test %hist -f with temporary filename.
 
@@ -63,59 +47,6 b' def doctest_hist_f():'
     In [11]: %history -n -f $tfile 3
     """
 
-def doctest_run_builtins():
-    """Check that %run doesn't damage __builtins__ via a doctest.
-
-    This is similar to the test_run_builtins, but I want *both* forms of the
-    test to catch any possible glitches in our testing machinery, since that
-    modifies %run somewhat.  So for this, we have both a normal test (below)
-    and a doctest (this one).
-
-    In [1]: import tempfile
-
-    In [2]: bid1 = id(__builtins__)
-
-    In [3]: f = tempfile.NamedTemporaryFile()
-
-    In [4]: f.write('pass\\n')
-
-    In [5]: f.flush()
-
-    In [6]: print 'B1:',type(__builtins__)
-    B1: <type 'module'>
-
-    In [7]: %run $f.name
-
-    In [8]: bid2 = id(__builtins__)
-
-    In [9]: print 'B2:',type(__builtins__)
-    B2: <type 'module'>
-
-    In [10]: bid1 == bid2
-    Out[10]: True
-    """
-
-def test_run_builtins():
-    """Check that %run doesn't damage __builtins__ """
-    import sys
-    import tempfile
-    import types
-
-    # Make an empty file and put 'pass' in it
-    f = tempfile.NamedTemporaryFile()
-    f.write('pass\n')
-    f.flush()
-
-    # Our first test is that the id of __builtins__ is not modified by %run
-    bid1 = id(__builtins__)
-    _ip.magic('run %s' % f.name)
-    bid2 = id(__builtins__)
-    yield nt.assert_equals,bid1,bid2
-    # However, the above could pass if __builtins__ was already modified to be
-    # a dict (it should be a module) by a previous use of %run.  So we also
-    # check explicitly that it really is a module:
-    yield nt.assert_equals,type(__builtins__),type(sys)
-    
 
 def doctest_hist_r():
     """Test %hist -r
@@ -201,3 +132,104 b' def doctest_refbug():'
     lowercased: hello
     lowercased: hello
     """
+
+#-----------------------------------------------------------------------------
+# Tests for %run
+#-----------------------------------------------------------------------------
+
+# %run is critical enough that it's a good idea to have a solid collection of
+# tests for it, some as doctests and some as normal tests.
+
+def doctest_run_ns():
+    """Classes declared %run scripts must be instantiable afterwards.
+
+    In [11]: run tclass foo
+
+    In [12]: isinstance(f(),foo)
+    Out[12]: True
+    """
+
+    
+def doctest_run_ns2():
+    """Classes declared %run scripts must be instantiable afterwards.
+
+    In [4]: run tclass C-first_pass
+
+    In [5]: run tclass C-second_pass
+    tclass.py: deleting object: C-first_pass
+    """
+
+def doctest_run_builtins():
+    """Check that %run doesn't damage __builtins__ via a doctest.
+
+    This is similar to the test_run_builtins, but I want *both* forms of the
+    test to catch any possible glitches in our testing machinery, since that
+    modifies %run somewhat.  So for this, we have both a normal test (below)
+    and a doctest (this one).
+
+    In [1]: import tempfile
+
+    In [2]: bid1 = id(__builtins__)
+
+    In [3]: f = tempfile.NamedTemporaryFile()
+
+    In [4]: f.write('pass\\n')
+
+    In [5]: f.flush()
+
+    In [6]: print 'B1:',type(__builtins__)
+    B1: <type 'module'>
+
+    In [7]: %run $f.name
+
+    In [8]: bid2 = id(__builtins__)
+
+    In [9]: print 'B2:',type(__builtins__)
+    B2: <type 'module'>
+
+    In [10]: bid1 == bid2
+    Out[10]: True
+    """
+
+# For some tests, it will be handy to organize them in a class with a common
+# setup that makes a temp file
+
+class TestMagicRun(object):
+
+    def setup(self):
+        """Make a valid python temp file."""
+        f = tempfile.NamedTemporaryFile()
+        f.write('pass\n')
+        f.flush()
+        self.tmpfile = f
+
+    def run_tmpfile(self):
+        _ip.magic('run %s' % self.tmpfile.name)
+
+    def test_builtins_id(self):
+        """Check that %run doesn't damage __builtins__ """
+
+        # Test that the id of __builtins__ is not modified by %run
+        bid1 = id(_ip.user_ns['__builtins__'])
+        self.run_tmpfile()
+        bid2 = id(_ip.user_ns['__builtins__'])
+        tt.assert_equals(bid1, bid2)
+
+    def test_builtins_type(self):
+        """Check that the type of __builtins__ doesn't change with %run.
+        
+        However, the above could pass if __builtins__ was already modified to
+        be a dict (it should be a module) by a previous use of %run.  So we
+        also check explicitly that it really is a module:
+        """
+        self.run_tmpfile()
+        tt.assert_equals(type(_ip.user_ns['__builtins__']),type(sys))
+
+    def test_prompts(self):
+        """Test that prompts correctly generate after %run"""
+        self.run_tmpfile()
+        p2 = str(_ip.IP.outputcache.prompt2).strip()
+        nt.assert_equals(p2[:3], '...')
+
+    def teardown(self):
+        self.tmpfile.close()