Don't assume test case for %time will finish in 0 time.

Closes gh-2899

IPython/core/tests/test_magic.py

@@ -1,837 +1,837 b''
 # -*- coding: utf-8 -*-
 """Tests for various magic functions.
 
 Needs to be run by nose (to make ipython session available).
 """
 from __future__ import absolute_import
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 import io
 import os
 import sys
 from StringIO import StringIO
 from unittest import TestCase
 
 try:
     from importlib import invalidate_caches   # Required from Python 3.3
 except ImportError:
     def invalidate_caches():
         pass
 
 import nose.tools as nt
 
 from IPython.core import magic
 from IPython.core.magic import (Magics, magics_class, line_magic,
                                 cell_magic, line_cell_magic,
                                 register_line_magic, register_cell_magic,
                                 register_line_cell_magic)
 from IPython.core.magics import execution, script, code
 from IPython.nbformat.v3.tests.nbexamples import nb0
 from IPython.nbformat import current
 from IPython.testing import decorators as dec
 from IPython.testing import tools as tt
 from IPython.utils import py3compat
 from IPython.utils.tempdir import TemporaryDirectory
 from IPython.utils.process import find_cmd
 
 #-----------------------------------------------------------------------------
 # Test functions begin
 #-----------------------------------------------------------------------------
 
 @magic.magics_class
 class DummyMagics(magic.Magics): pass
 
 def test_rehashx():
     # clear up everything
     _ip = get_ipython()
     _ip.alias_manager.alias_table.clear()
     del _ip.db['syscmdlist']
     
     _ip.magic('rehashx')
     # Practically ALL ipython development systems will have more than 10 aliases
 
     yield (nt.assert_true, len(_ip.alias_manager.alias_table) > 10)
     for key, val in _ip.alias_manager.alias_table.iteritems():
         # we must strip dots from alias names
         nt.assert_true('.' not in key)
 
     # rehashx must fill up syscmdlist
     scoms = _ip.db['syscmdlist']
     yield (nt.assert_true, len(scoms) > 10)
 
 
 def test_magic_parse_options():
     """Test that we don't mangle paths when parsing magic options."""
     ip = get_ipython()
     path = 'c:\\x'
     m = DummyMagics(ip)
     opts = m.parse_options('-f %s' % path,'f:')[0]
     # argv splitting is os-dependent
     if os.name == 'posix':
         expected = 'c:x'
     else:
         expected = path
     nt.assert_equal(opts['f'], expected)
 
 def test_magic_parse_long_options():
     """Magic.parse_options can handle --foo=bar long options"""
     ip = get_ipython()
     m = DummyMagics(ip)
     opts, _ = m.parse_options('--foo --bar=bubble', 'a', 'foo', 'bar=')
     nt.assert_true('foo' in opts)
     nt.assert_true('bar' in opts)
     nt.assert_true(opts['bar'], "bubble")
 
 
 @dec.skip_without('sqlite3')
 def doctest_hist_f():
     """Test %hist -f with temporary filename.
 
     In [9]: import tempfile
 
     In [10]: tfile = tempfile.mktemp('.py','tmp-ipython-')
 
     In [11]: %hist -nl -f $tfile 3
 
     In [13]: import os; os.unlink(tfile)
     """
 
 
 @dec.skip_without('sqlite3')
 def doctest_hist_r():
     """Test %hist -r
 
     XXX - This test is not recording the output correctly.  For some reason, in
     testing mode the raw history isn't getting populated.  No idea why.
     Disabling the output checking for now, though at least we do run it.
 
     In [1]: 'hist' in _ip.lsmagic()
     Out[1]: True
 
     In [2]: x=1
 
     In [3]: %hist -rl 2
     x=1 # random
     %hist -r 2
     """
 
 
 @dec.skip_without('sqlite3')
 def doctest_hist_op():
     """Test %hist -op
 
     In [1]: class b(float):
        ...:     pass
        ...: 
 
     In [2]: class s(object):
        ...:     def __str__(self):
        ...:         return 's'
        ...: 
 
     In [3]: 
 
     In [4]: class r(b):
        ...:     def __repr__(self):
        ...:         return 'r'
        ...: 
 
     In [5]: class sr(s,r): pass
        ...: 
 
     In [6]: 
 
     In [7]: bb=b()
 
     In [8]: ss=s()
 
     In [9]: rr=r()
 
     In [10]: ssrr=sr()
 
     In [11]: 4.5
     Out[11]: 4.5
 
     In [12]: str(ss)
     Out[12]: 's'
 
     In [13]: 
 
     In [14]: %hist -op
     >>> class b:
     ...     pass
     ... 
     >>> class s(b):
     ...     def __str__(self):
     ...         return 's'
     ... 
     >>> 
     >>> class r(b):
     ...     def __repr__(self):
     ...         return 'r'
     ... 
     >>> class sr(s,r): pass
     >>> 
     >>> bb=b()
     >>> ss=s()
     >>> rr=r()
     >>> ssrr=sr()
     >>> 4.5
     4.5
     >>> str(ss)
     's'
     >>> 
     """
 
 
 @dec.skip_without('sqlite3')
 def test_macro():
     ip = get_ipython()
     ip.history_manager.reset()   # Clear any existing history.
     cmds = ["a=1", "def b():\n  return a**2", "print(a,b())"]
     for i, cmd in enumerate(cmds, start=1):
         ip.history_manager.store_inputs(i, cmd)
     ip.magic("macro test 1-3")
     nt.assert_equal(ip.user_ns["test"].value, "\n".join(cmds)+"\n")
     
     # List macros.
     assert "test" in ip.magic("macro")
 
 
 @dec.skip_without('sqlite3')
 def test_macro_run():
     """Test that we can run a multi-line macro successfully."""
     ip = get_ipython()
     ip.history_manager.reset()
     cmds = ["a=10", "a+=1", py3compat.doctest_refactor_print("print a"),
                                                             "%macro test 2-3"]
     for cmd in cmds:
         ip.run_cell(cmd, store_history=True)
     nt.assert_equal(ip.user_ns["test"].value,
                             py3compat.doctest_refactor_print("a+=1\nprint a\n"))
     with tt.AssertPrints("12"):
         ip.run_cell("test")
     with tt.AssertPrints("13"):
         ip.run_cell("test")
 
 
 @dec.skipif_not_numpy
 def test_numpy_reset_array_undec():
     "Test '%reset array' functionality"
     _ip.ex('import numpy as np')
     _ip.ex('a = np.empty(2)')
     yield (nt.assert_true, 'a' in _ip.user_ns)
     _ip.magic('reset -f array')
     yield (nt.assert_false, 'a' in _ip.user_ns)
 
 def test_reset_out():
     "Test '%reset out' magic"
     _ip.run_cell("parrot = 'dead'", store_history=True)
     # test '%reset -f out', make an Out prompt
     _ip.run_cell("parrot", store_history=True)
     nt.assert_true('dead' in [_ip.user_ns[x] for x in '_','__','___'])
     _ip.magic('reset -f out')
     nt.assert_false('dead' in [_ip.user_ns[x] for x in '_','__','___'])
     nt.assert_true(len(_ip.user_ns['Out']) == 0)
 
 def test_reset_in():
     "Test '%reset in' magic"
     # test '%reset -f in'
     _ip.run_cell("parrot", store_history=True)
     nt.assert_true('parrot' in [_ip.user_ns[x] for x in '_i','_ii','_iii'])
     _ip.magic('%reset -f in')
     nt.assert_false('parrot' in [_ip.user_ns[x] for x in '_i','_ii','_iii'])
     nt.assert_true(len(set(_ip.user_ns['In'])) == 1)
 
 def test_reset_dhist():
     "Test '%reset dhist' magic"
     _ip.run_cell("tmp = [d for d in _dh]") # copy before clearing
     _ip.magic('cd ' + os.path.dirname(nt.__file__))
     _ip.magic('cd -')
     nt.assert_true(len(_ip.user_ns['_dh']) > 0)
     _ip.magic('reset -f dhist')
     nt.assert_true(len(_ip.user_ns['_dh']) == 0)
     _ip.run_cell("_dh = [d for d in tmp]") #restore
 
 def test_reset_in_length():
     "Test that '%reset in' preserves In[] length"
     _ip.run_cell("print 'foo'")
     _ip.run_cell("reset -f in")
     nt.assert_true(len(_ip.user_ns['In']) == _ip.displayhook.prompt_count+1)
 
 def test_tb_syntaxerror():
     """test %tb after a SyntaxError"""
     ip = get_ipython()
     ip.run_cell("for")
     
     # trap and validate stdout
     save_stdout = sys.stdout
     try:
         sys.stdout = StringIO()
         ip.run_cell("%tb")
         out = sys.stdout.getvalue()
     finally:
         sys.stdout = save_stdout
     # trim output, and only check the last line
     last_line = out.rstrip().splitlines()[-1].strip()
     nt.assert_equal(last_line, "SyntaxError: invalid syntax")
 
 
 def test_time():
     ip = get_ipython()
     
-    with tt.AssertPrints("CPU times: user 0 ns, sys: 0 ns, total: 0 ns"):
+    with tt.AssertPrints("CPU times: user "):
         ip.run_cell("%time None")
     
     ip.run_cell("def f(kmjy):\n"
                 "    %time print (2*kmjy)")
     
-    with tt.AssertPrints("CPU times: user 0 ns, sys: 0 ns, total: 0 ns"):
+    with tt.AssertPrints("CPU times: user "):
         with tt.AssertPrints("hihi", suppress=False):
             ip.run_cell("f('hi')")
 
 def test_doctest_mode():
     "Toggle doctest_mode twice, it should be a no-op and run without error"
     _ip.magic('doctest_mode')
     _ip.magic('doctest_mode')
 
 
 def test_parse_options():
     """Tests for basic options parsing in magics."""
     # These are only the most minimal of tests, more should be added later.  At
     # the very least we check that basic text/unicode calls work OK.
     m = DummyMagics(_ip)
     nt.assert_equal(m.parse_options('foo', '')[1], 'foo')
     nt.assert_equal(m.parse_options(u'foo', '')[1], u'foo')
 
     
 def test_dirops():
     """Test various directory handling operations."""
     # curpath = lambda :os.path.splitdrive(os.getcwdu())[1].replace('\\','/')
     curpath = os.getcwdu
     startdir = os.getcwdu()
     ipdir = os.path.realpath(_ip.ipython_dir)
     try:
         _ip.magic('cd "%s"' % ipdir)
         nt.assert_equal(curpath(), ipdir)
         _ip.magic('cd -')
         nt.assert_equal(curpath(), startdir)
         _ip.magic('pushd "%s"' % ipdir)
         nt.assert_equal(curpath(), ipdir)
         _ip.magic('popd')
         nt.assert_equal(curpath(), startdir)
     finally:
         os.chdir(startdir)
 
 
 def test_xmode():
     # Calling xmode three times should be a no-op
     xmode = _ip.InteractiveTB.mode
     for i in range(3):
         _ip.magic("xmode")
     nt.assert_equal(_ip.InteractiveTB.mode, xmode)
     
 def test_reset_hard():
     monitor = []
     class A(object):
         def __del__(self):
             monitor.append(1)
         def __repr__(self):
             return "<A instance>"
             
     _ip.user_ns["a"] = A()
     _ip.run_cell("a")
     
     nt.assert_equal(monitor, [])
     _ip.magic("reset -f")
     nt.assert_equal(monitor, [1])
     
 class TestXdel(tt.TempFileMixin):
     def test_xdel(self):
         """Test that references from %run are cleared by xdel."""
         src = ("class A(object):\n"
                "    monitor = []\n"
                "    def __del__(self):\n"
                "        self.monitor.append(1)\n"
                "a = A()\n")
         self.mktmp(src)
         # %run creates some hidden references...
         _ip.magic("run %s" % self.fname)
         # ... as does the displayhook.
         _ip.run_cell("a")
         
         monitor = _ip.user_ns["A"].monitor
         nt.assert_equal(monitor, [])
         
         _ip.magic("xdel a")
         
         # Check that a's __del__ method has been called.
         nt.assert_equal(monitor, [1])
 
 def doctest_who():
     """doctest for %who
     
     In [1]: %reset -f
     
     In [2]: alpha = 123
     
     In [3]: beta = 'beta'
     
     In [4]: %who int
     alpha
     
     In [5]: %who str
     beta
     
     In [6]: %whos
     Variable   Type    Data/Info
     ----------------------------
     alpha      int     123
     beta       str     beta
     
     In [7]: %who_ls
     Out[7]: ['alpha', 'beta']
     """
 
 def test_whos():
     """Check that whos is protected against objects where repr() fails."""
     class A(object):
         def __repr__(self):
             raise Exception()
     _ip.user_ns['a'] = A()
     _ip.magic("whos")
 
 @py3compat.u_format
 def doctest_precision():
     """doctest for %precision
     
     In [1]: f = get_ipython().display_formatter.formatters['text/plain']
     
     In [2]: %precision 5
     Out[2]: {u}'%.5f'
     
     In [3]: f.float_format
     Out[3]: {u}'%.5f'
     
     In [4]: %precision %e
     Out[4]: {u}'%e'
     
     In [5]: f(3.1415927)
     Out[5]: {u}'3.141593e+00'
     """
 
 def test_psearch():
     with tt.AssertPrints("dict.fromkeys"):
         _ip.run_cell("dict.fr*?")
 
 def test_timeit_shlex():
     """test shlex issues with timeit (#1109)"""
     _ip.ex("def f(*a,**kw): pass")
     _ip.magic('timeit -n1 "this is a bug".count(" ")')
     _ip.magic('timeit -r1 -n1 f(" ", 1)')
     _ip.magic('timeit -r1 -n1 f(" ", 1, " ", 2, " ")')
     _ip.magic('timeit -r1 -n1 ("a " + "b")')
     _ip.magic('timeit -r1 -n1 f("a " + "b")')
     _ip.magic('timeit -r1 -n1 f("a " + "b ")')
 
 
 def test_timeit_arguments():
     "Test valid timeit arguments, should not cause SyntaxError (GH #1269)"
     _ip.magic("timeit ('#')")
 
 
 def test_timeit_special_syntax():
     "Test %%timeit with IPython special syntax"
     from IPython.core.magic import register_line_magic
 
     @register_line_magic
     def lmagic(line):
         ip = get_ipython()
         ip.user_ns['lmagic_out'] = line
 
     # line mode test
     _ip.run_line_magic('timeit', '-n1 -r1 %lmagic my line')
     nt.assert_equal(_ip.user_ns['lmagic_out'], 'my line')
     # cell mode test
     _ip.run_cell_magic('timeit', '-n1 -r1', '%lmagic my line2')
     nt.assert_equal(_ip.user_ns['lmagic_out'], 'my line2')
     
 
 @dec.skipif(execution.profile is None)
 def test_prun_quotes():
     "Test that prun does not clobber string escapes (GH #1302)"
     _ip.magic(r"prun -q x = '\t'")
     nt.assert_equal(_ip.user_ns['x'], '\t')
 
 def test_extension():
     tmpdir = TemporaryDirectory()
     orig_ipython_dir = _ip.ipython_dir
     try:
         _ip.ipython_dir = tmpdir.name
         nt.assert_raises(ImportError, _ip.magic, "load_ext daft_extension")
         url = os.path.join(os.path.dirname(__file__), "daft_extension.py")
         _ip.magic("install_ext %s" % url)
         _ip.user_ns.pop('arq', None)
         invalidate_caches()   # Clear import caches
         _ip.magic("load_ext daft_extension")
         nt.assert_equal(_ip.user_ns['arq'], 185)
         _ip.magic("unload_ext daft_extension")
         assert 'arq' not in _ip.user_ns
     finally:
         _ip.ipython_dir = orig_ipython_dir
         tmpdir.cleanup()
         
 def test_notebook_export_json():
     with TemporaryDirectory() as td:
         outfile = os.path.join(td, "nb.ipynb")
         _ip.ex(py3compat.u_format(u"u = {u}'héllo'"))
         _ip.magic("notebook -e %s" % outfile)
 
 def test_notebook_export_py():
     with TemporaryDirectory() as td:
         outfile = os.path.join(td, "nb.py")
         _ip.ex(py3compat.u_format(u"u = {u}'héllo'"))
         _ip.magic("notebook -e %s" % outfile)
 
 def test_notebook_reformat_py():
     with TemporaryDirectory() as td:
         infile = os.path.join(td, "nb.ipynb")
         with io.open(infile, 'w', encoding='utf-8') as f:
             current.write(nb0, f, 'json')
             
         _ip.ex(py3compat.u_format(u"u = {u}'héllo'"))
         _ip.magic("notebook -f py %s" % infile)
 
 def test_notebook_reformat_json():
     with TemporaryDirectory() as td:
         infile = os.path.join(td, "nb.py")
         with io.open(infile, 'w', encoding='utf-8') as f:
             current.write(nb0, f, 'py')
             
         _ip.ex(py3compat.u_format(u"u = {u}'héllo'"))
         _ip.magic("notebook -f ipynb %s" % infile)
         _ip.magic("notebook -f json %s" % infile)
 
 def test_env():
     env = _ip.magic("env")
     assert isinstance(env, dict), type(env)
 
 
 class CellMagicTestCase(TestCase):
 
     def check_ident(self, magic):
         # Manually called, we get the result
         out = _ip.run_cell_magic(magic, 'a', 'b')
         nt.assert_equal(out, ('a','b'))
         # Via run_cell, it goes into the user's namespace via displayhook
         _ip.run_cell('%%' + magic +' c\nd')
         nt.assert_equal(_ip.user_ns['_'], ('c','d'))
 
     def test_cell_magic_func_deco(self):
         "Cell magic using simple decorator"
         @register_cell_magic
         def cellm(line, cell):
             return line, cell
 
         self.check_ident('cellm')
 
     def test_cell_magic_reg(self):
         "Cell magic manually registered"
         def cellm(line, cell):
             return line, cell
 
         _ip.register_magic_function(cellm, 'cell', 'cellm2')
         self.check_ident('cellm2')
 
     def test_cell_magic_class(self):
         "Cell magics declared via a class"
         @magics_class
         class MyMagics(Magics):
 
             @cell_magic
             def cellm3(self, line, cell):
                 return line, cell
 
         _ip.register_magics(MyMagics)
         self.check_ident('cellm3')
 
     def test_cell_magic_class2(self):
         "Cell magics declared via a class, #2"
         @magics_class
         class MyMagics2(Magics):
 
             @cell_magic('cellm4')
             def cellm33(self, line, cell):
                 return line, cell
             
         _ip.register_magics(MyMagics2)
         self.check_ident('cellm4')
         # Check that nothing is registered as 'cellm33'
         c33 = _ip.find_cell_magic('cellm33')
         nt.assert_equal(c33, None)
 
 def test_file():
     """Basic %%file"""
     ip = get_ipython()
     with TemporaryDirectory() as td:
         fname = os.path.join(td, 'file1')
         ip.run_cell_magic("file", fname, u'\n'.join([
             'line1',
             'line2',
         ]))
         with open(fname) as f:
             s = f.read()
         nt.assert_in('line1\n', s)
         nt.assert_in('line2', s)
 
 def test_file_var_expand():
     """%%file $filename"""
     ip = get_ipython()
     with TemporaryDirectory() as td:
         fname = os.path.join(td, 'file1')
         ip.user_ns['filename'] = fname
         ip.run_cell_magic("file", '$filename', u'\n'.join([
             'line1',
             'line2',
         ]))
         with open(fname) as f:
             s = f.read()
         nt.assert_in('line1\n', s)
         nt.assert_in('line2', s)
 
 def test_file_unicode():
     """%%file with unicode cell"""
     ip = get_ipython()
     with TemporaryDirectory() as td:
         fname = os.path.join(td, 'file1')
         ip.run_cell_magic("file", fname, u'\n'.join([
             u'liné1',
             u'liné2',
         ]))
         with io.open(fname, encoding='utf-8') as f:
             s = f.read()
         nt.assert_in(u'liné1\n', s)
         nt.assert_in(u'liné2', s)
 
 def test_file_amend():
     """%%file -a amends files"""
     ip = get_ipython()
     with TemporaryDirectory() as td:
         fname = os.path.join(td, 'file2')
         ip.run_cell_magic("file", fname, u'\n'.join([
             'line1',
             'line2',
         ]))
         ip.run_cell_magic("file", "-a %s" % fname, u'\n'.join([
             'line3',
             'line4',
         ]))
         with open(fname) as f:
             s = f.read()
         nt.assert_in('line1\n', s)
         nt.assert_in('line3\n', s)
         
     
 def test_script_config():
     ip = get_ipython()
     ip.config.ScriptMagics.script_magics = ['whoda']
     sm = script.ScriptMagics(shell=ip)
     nt.assert_in('whoda', sm.magics['cell'])
 
 @dec.skip_win32
 def test_script_out():
     ip = get_ipython()
     ip.run_cell_magic("script", "--out output sh", "echo 'hi'")
     nt.assert_equal(ip.user_ns['output'], 'hi\n')
 
 @dec.skip_win32
 def test_script_err():
     ip = get_ipython()
     ip.run_cell_magic("script", "--err error sh", "echo 'hello' >&2")
     nt.assert_equal(ip.user_ns['error'], 'hello\n')
 
 @dec.skip_win32
 def test_script_out_err():
     ip = get_ipython()
     ip.run_cell_magic("script", "--out output --err error sh", "echo 'hi'\necho 'hello' >&2")
     nt.assert_equal(ip.user_ns['output'], 'hi\n')
     nt.assert_equal(ip.user_ns['error'], 'hello\n')
 
 @dec.skip_win32
 def test_script_bg_out():
     ip = get_ipython()
     ip.run_cell_magic("script", "--bg --out output sh", "echo 'hi'")
     nt.assert_equal(ip.user_ns['output'].read(), b'hi\n')
 
 @dec.skip_win32
 def test_script_bg_err():
     ip = get_ipython()
     ip.run_cell_magic("script", "--bg --err error sh", "echo 'hello' >&2")
     nt.assert_equal(ip.user_ns['error'].read(), b'hello\n')
 
 @dec.skip_win32
 def test_script_bg_out_err():
     ip = get_ipython()
     ip.run_cell_magic("script", "--bg --out output --err error sh", "echo 'hi'\necho 'hello' >&2")
     nt.assert_equal(ip.user_ns['output'].read(), b'hi\n')
     nt.assert_equal(ip.user_ns['error'].read(), b'hello\n')
 
 def test_script_defaults():
     ip = get_ipython()
     for cmd in ['sh', 'bash', 'perl', 'ruby']:
         try:
             find_cmd(cmd)
         except Exception:
             pass
         else:
             nt.assert_in(cmd, ip.magics_manager.magics['cell'])
 
 
 @magics_class
 class FooFoo(Magics):
     """class with both %foo and %%foo magics"""
     @line_magic('foo')
     def line_foo(self, line):
         "I am line foo"
         pass
 
     @cell_magic("foo")
     def cell_foo(self, line, cell):
         "I am cell foo, not line foo"
         pass
 
 def test_line_cell_info():
     """%%foo and %foo magics are distinguishable to inspect"""
     ip = get_ipython()
     ip.magics_manager.register(FooFoo)
     oinfo = ip.object_inspect('foo')
     nt.assert_true(oinfo['found'])
     nt.assert_true(oinfo['ismagic'])
     
     oinfo = ip.object_inspect('%%foo')
     nt.assert_true(oinfo['found'])
     nt.assert_true(oinfo['ismagic'])
     nt.assert_equal(oinfo['docstring'], FooFoo.cell_foo.__doc__)
 
     oinfo = ip.object_inspect('%foo')
     nt.assert_true(oinfo['found'])
     nt.assert_true(oinfo['ismagic'])
     nt.assert_equal(oinfo['docstring'], FooFoo.line_foo.__doc__)
 
 def test_multiple_magics():
     ip = get_ipython()
     foo1 = FooFoo(ip)
     foo2 = FooFoo(ip)
     mm = ip.magics_manager
     mm.register(foo1)
     nt.assert_true(mm.magics['line']['foo'].im_self is foo1)
     mm.register(foo2)
     nt.assert_true(mm.magics['line']['foo'].im_self is foo2)
 
 def test_alias_magic():
     """Test %alias_magic."""
     ip = get_ipython()
     mm = ip.magics_manager
 
     # Basic operation: both cell and line magics are created, if possible.
     ip.run_line_magic('alias_magic', 'timeit_alias timeit')
     nt.assert_true('timeit_alias' in mm.magics['line'])
     nt.assert_true('timeit_alias' in mm.magics['cell'])
 
     # --cell is specified, line magic not created.
     ip.run_line_magic('alias_magic', '--cell timeit_cell_alias timeit')
     nt.assert_false('timeit_cell_alias' in mm.magics['line'])
     nt.assert_true('timeit_cell_alias' in mm.magics['cell'])
 
     # Test that line alias is created successfully.
     ip.run_line_magic('alias_magic', '--line env_alias env')
     nt.assert_equal(ip.run_line_magic('env', ''),
                     ip.run_line_magic('env_alias', ''))
 
 def test_save():
     """Test %save."""
     ip = get_ipython()
     ip.history_manager.reset()   # Clear any existing history.
     cmds = [u"a=1", u"def b():\n  return a**2", u"print(a, b())"]
     for i, cmd in enumerate(cmds, start=1):
         ip.history_manager.store_inputs(i, cmd)
     with TemporaryDirectory() as tmpdir:
         file = os.path.join(tmpdir, "testsave.py")
         ip.run_line_magic("save", "%s 1-10" % file)
         with open(file) as f:
             content = f.read()
             nt.assert_equal(content.count(cmds[0]), 1)
             nt.assert_true('coding: utf-8' in content)
         ip.run_line_magic("save", "-a %s 1-10" % file)
         with open(file) as f:
             content = f.read()
             nt.assert_equal(content.count(cmds[0]), 2)
             nt.assert_true('coding: utf-8' in content)
 
 
 def test_store():
     """Test %store."""
     ip = get_ipython()
     ip.run_line_magic('load_ext', 'storemagic')
     
     # make sure the storage is empty
     ip.run_line_magic('store', '-z')
     ip.user_ns['var'] = 42
     ip.run_line_magic('store', 'var')
     ip.user_ns['var'] = 39
     ip.run_line_magic('store', '-r')
     nt.assert_equal(ip.user_ns['var'], 42)
 
     ip.run_line_magic('store', '-d var')
     ip.user_ns['var'] = 39
     ip.run_line_magic('store' , '-r')
     nt.assert_equal(ip.user_ns['var'], 39)
 
 
 def _run_edit_test(arg_s, exp_filename=None,
                         exp_lineno=-1,
                         exp_contents=None,
                         exp_is_temp=None):
     ip = get_ipython()
     M = code.CodeMagics(ip)
     last_call = ['','']
     opts,args = M.parse_options(arg_s,'prxn:')
     filename, lineno, is_temp = M._find_edit_target(ip, args, opts, last_call)
         
     if exp_filename is not None:
         nt.assert_equal(exp_filename, filename)
     if exp_contents is not None:
         with io.open(filename, 'r') as f:
             contents = f.read()
         nt.assert_equal(exp_contents, contents)
     if exp_lineno != -1:
         nt.assert_equal(exp_lineno, lineno)
     if exp_is_temp is not None:
         nt.assert_equal(exp_is_temp, is_temp)
 
 
 def test_edit_interactive():
     """%edit on interactively defined objects"""
     ip = get_ipython()
     n = ip.execution_count
     ip.run_cell(u"def foo(): return 1", store_history=True)
     
     try:
         _run_edit_test("foo")
     except code.InteractivelyDefined as e:
         nt.assert_equal(e.index, n)
     else:
         raise AssertionError("Should have raised InteractivelyDefined")
 
 
 def test_edit_cell():
     """%edit [cell id]"""
     ip = get_ipython()
     
     ip.run_cell(u"def foo(): return 1", store_history=True)
     
     # test
     _run_edit_test("1", exp_contents=ip.user_ns['In'][1], exp_is_temp=True)