Expose IPython machinery for testing code completeness

IPython/core/inputsplitter.py

@@ -1,638 +1,654 b''
 """Input handling and transformation machinery.
 
 The first class in this module, :class:`InputSplitter`, is designed to tell when
 input from a line-oriented frontend is complete and should be executed, and when
 the user should be prompted for another line of code instead. The name 'input
 splitter' is largely for historical reasons.
 
 A companion, :class:`IPythonInputSplitter`, provides the same functionality but
 with full support for the extended IPython syntax (magics, system calls, etc).
 The code to actually do these transformations is in :mod:`IPython.core.inputtransformer`.
 :class:`IPythonInputSplitter` feeds the raw code to the transformers in order
 and stores the results.
 
 For more details, see the class docstrings below.
 
 Authors
 -------
 
 * Fernando Perez
 * Brian Granger
 * Thomas Kluyver
 """
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2010  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.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 # stdlib
 import ast
 import codeop
 import re
 import sys
 
 # IPython modules
 from IPython.utils.py3compat import cast_unicode
 from IPython.core.inputtransformer import (leading_indent,
                                            classic_prompt,
                                            ipy_prompt,
                                            strip_encoding_cookie,
                                            cellmagic,
                                            assemble_logical_lines,
                                            help_end,
                                            escaped_commands,
                                            assign_from_magic,
                                            assign_from_system,
                                            assemble_python_lines,
                                            )
 
 # These are available in this module for backwards compatibility.
 from IPython.core.inputtransformer import (ESC_SHELL, ESC_SH_CAP, ESC_HELP,
                                         ESC_HELP2, ESC_MAGIC, ESC_MAGIC2,
                                         ESC_QUOTE, ESC_QUOTE2, ESC_PAREN, ESC_SEQUENCES)
 
 #-----------------------------------------------------------------------------
 # Utilities
 #-----------------------------------------------------------------------------
 
 # FIXME: These are general-purpose utilities that later can be moved to the
 # general ward.  Kept here for now because we're being very strict about test
 # coverage with this code, and this lets us ensure that we keep 100% coverage
 # while developing.
 
 # compiled regexps for autoindent management
 dedent_re = re.compile('|'.join([
     r'^\s+raise(\s.*)?$', # raise statement (+ space + other stuff, maybe)
     r'^\s+raise\([^\)]*\).*$', # wacky raise with immediate open paren
     r'^\s+return(\s.*)?$', # normal return (+ space + other stuff, maybe)
     r'^\s+return\([^\)]*\).*$', # wacky return with immediate open paren
     r'^\s+pass\s*$', # pass (optionally followed by trailing spaces)
     r'^\s+break\s*$', # break (optionally followed by trailing spaces)
     r'^\s+continue\s*$', # continue (optionally followed by trailing spaces)
 ]))
 ini_spaces_re = re.compile(r'^([ \t\r\f\v]+)')
 
 # regexp to match pure comment lines so we don't accidentally insert 'if 1:'
 # before pure comments
 comment_line_re = re.compile('^\s*\#')
 
 
 def num_ini_spaces(s):
     """Return the number of initial spaces in a string.
 
     Note that tabs are counted as a single space.  For now, we do *not* support
     mixing of tabs and spaces in the user's input.
 
     Parameters
     ----------
     s : string
 
     Returns
     -------
     n : int
     """
 
     ini_spaces = ini_spaces_re.match(s)
     if ini_spaces:
         return ini_spaces.end()
     else:
         return 0
 
 def last_blank(src):
     """Determine if the input source ends in a blank.
 
     A blank is either a newline or a line consisting of whitespace.
 
     Parameters
     ----------
     src : string
       A single or multiline string.
     """
     if not src: return False
     ll  = src.splitlines()[-1]
     return (ll == '') or ll.isspace()
 
 
 last_two_blanks_re = re.compile(r'\n\s*\n\s*$', re.MULTILINE)
 last_two_blanks_re2 = re.compile(r'.+\n\s*\n\s+$', re.MULTILINE)
 
 def last_two_blanks(src):
     """Determine if the input source ends in two blanks.
 
     A blank is either a newline or a line consisting of whitespace.
 
     Parameters
     ----------
     src : string
       A single or multiline string.
     """
     if not src: return False
     # The logic here is tricky: I couldn't get a regexp to work and pass all
     # the tests, so I took a different approach: split the source by lines,
     # grab the last two and prepend '###\n' as a stand-in for whatever was in
     # the body before the last two lines.  Then, with that structure, it's
     # possible to analyze with two regexps.  Not the most elegant solution, but
     # it works.  If anyone tries to change this logic, make sure to validate
     # the whole test suite first!
     new_src = '\n'.join(['###\n'] + src.splitlines()[-2:])
     return (bool(last_two_blanks_re.match(new_src)) or
             bool(last_two_blanks_re2.match(new_src)) )
 
 
 def remove_comments(src):
     """Remove all comments from input source.
 
     Note: comments are NOT recognized inside of strings!
 
     Parameters
     ----------
     src : string
       A single or multiline input string.
 
     Returns
     -------
     String with all Python comments removed.
     """
 
     return re.sub('#.*', '', src)
 
 
 def get_input_encoding():
     """Return the default standard input encoding.
 
     If sys.stdin has no encoding, 'ascii' is returned."""
     # There are strange environments for which sys.stdin.encoding is None. We
     # ensure that a valid encoding is returned.
     encoding = getattr(sys.stdin, 'encoding', None)
     if encoding is None:
         encoding = 'ascii'
     return encoding
 
 #-----------------------------------------------------------------------------
 # Classes and functions for normal Python syntax handling
 #-----------------------------------------------------------------------------
 
 class InputSplitter(object):
     r"""An object that can accumulate lines of Python source before execution.
 
     This object is designed to be fed python source line-by-line, using
     :meth:`push`. It will return on each push whether the currently pushed
     code could be executed already. In addition, it provides a method called
     :meth:`push_accepts_more` that can be used to query whether more input
     can be pushed into a single interactive block.
 
     This is a simple example of how an interactive terminal-based client can use
     this tool::
 
         isp = InputSplitter()
         while isp.push_accepts_more():
             indent = ' '*isp.indent_spaces
             prompt = '>>> ' + indent
             line = indent + raw_input(prompt)
             isp.push(line)
         print 'Input source was:\n', isp.source_reset(),
     """
     # Number of spaces of indentation computed from input that has been pushed
     # so far.  This is the attributes callers should query to get the current
     # indentation level, in order to provide auto-indent facilities.
     indent_spaces = 0
     # String, indicating the default input encoding.  It is computed by default
     # at initialization time via get_input_encoding(), but it can be reset by a
     # client with specific knowledge of the encoding.
     encoding = ''
     # String where the current full source input is stored, properly encoded.
     # Reading this attribute is the normal way of querying the currently pushed
     # source code, that has been properly encoded.
     source = ''
     # Code object corresponding to the current source.  It is automatically
     # synced to the source, so it can be queried at any time to obtain the code
     # object; it will be None if the source doesn't compile to valid Python.
     code = None
 
     # Private attributes
 
     # List with lines of input accumulated so far
     _buffer = None
     # Command compiler
     _compile = None
     # Mark when input has changed indentation all the way back to flush-left
     _full_dedent = False
     # Boolean indicating whether the current block is complete
     _is_complete = None
 
     def __init__(self):
         """Create a new InputSplitter instance.
         """
         self._buffer = []
         self._compile = codeop.CommandCompiler()
         self.encoding = get_input_encoding()
 
     def reset(self):
         """Reset the input buffer and associated state."""
         self.indent_spaces = 0
         self._buffer[:] = []
         self.source = ''
         self.code = None
         self._is_complete = False
         self._full_dedent = False
 
     def source_reset(self):
         """Return the input source and perform a full reset.
         """
         out = self.source
         self.reset()
         return out
 
+    def is_complete(self, source):
+        """Return whether a block of code is ready to execute, or should be continued
+        
+        This is a non-stateful API, and will reset the state of this InputSplitter.
+        """
+        self.reset()
+        try:
+            self.push(source)
+            return not self.push_accepts_more()
+        except SyntaxError:
+            # Transformers in IPythonInputSplitter can raise SyntaxError,
+            # which push() will not catch.
+            return True
+        finally:
+            self.reset()
+
     def push(self, lines):
         """Push one or more lines of input.
 
         This stores the given lines and returns a status code indicating
         whether the code forms a complete Python block or not.
 
         Any exceptions generated in compilation are swallowed, but if an
         exception was produced, the method returns True.
 
         Parameters
         ----------
         lines : string
           One or more lines of Python input.
 
         Returns
         -------
         is_complete : boolean
           True if the current input source (the result of the current input
           plus prior inputs) forms a complete Python execution block.  Note that
           this value is also stored as a private attribute (``_is_complete``), so it
           can be queried at any time.
         """
         self._store(lines)
         source = self.source
 
         # Before calling _compile(), reset the code object to None so that if an
         # exception is raised in compilation, we don't mislead by having
         # inconsistent code/source attributes.
         self.code, self._is_complete = None, None
 
         # Honor termination lines properly
         if source.endswith('\\\n'):
             return False
 
         self._update_indent(lines)
         try:
             self.code = self._compile(source, symbol="exec")
         # Invalid syntax can produce any of a number of different errors from
         # inside the compiler, so we have to catch them all.  Syntax errors
         # immediately produce a 'ready' block, so the invalid Python can be
         # sent to the kernel for evaluation with possible ipython
         # special-syntax conversion.
         except (SyntaxError, OverflowError, ValueError, TypeError,
                 MemoryError):
             self._is_complete = True
         else:
             # Compilation didn't produce any exceptions (though it may not have
             # given a complete code object)
             self._is_complete = self.code is not None
 
         return self._is_complete
 
     def push_accepts_more(self):
         """Return whether a block of interactive input can accept more input.
 
         This method is meant to be used by line-oriented frontends, who need to
         guess whether a block is complete or not based solely on prior and
         current input lines.  The InputSplitter considers it has a complete
         interactive block and will not accept more input when either:
         
         * A SyntaxError is raised
 
         * The code is complete and consists of a single line or a single
           non-compound statement
 
         * The code is complete and has a blank line at the end
 
         If the current input produces a syntax error, this method immediately
         returns False but does *not* raise the syntax error exception, as
         typically clients will want to send invalid syntax to an execution
         backend which might convert the invalid syntax into valid Python via
         one of the dynamic IPython mechanisms.
         """
 
         # With incomplete input, unconditionally accept more
         # A syntax error also sets _is_complete to True - see push()
         if not self._is_complete:
             #print("Not complete")  # debug
             return True
         
         # The user can make any (complete) input execute by leaving a blank line
         last_line = self.source.splitlines()[-1]
         if (not last_line) or last_line.isspace():
             #print("Blank line")  # debug
             return False
         
         # If there's just a single line or AST node, and we're flush left, as is
         # the case after a simple statement such as 'a=1', we want to execute it
         # straight away.
         if self.indent_spaces==0:
             if len(self.source.splitlines()) <= 1:
                 return False
             
             try:
                 code_ast = ast.parse(u''.join(self._buffer))
             except Exception:
                 #print("Can't parse AST")  # debug
                 return False
             else:
                 if len(code_ast.body) == 1 and \
                                     not hasattr(code_ast.body[0], 'body'):
                     #print("Simple statement")  # debug
                     return False
 
         # General fallback - accept more code
         return True
 
     #------------------------------------------------------------------------
     # Private interface
     #------------------------------------------------------------------------
 
     def _find_indent(self, line):
         """Compute the new indentation level for a single line.
 
         Parameters
         ----------
         line : str
           A single new line of non-whitespace, non-comment Python input.
 
         Returns
         -------
         indent_spaces : int
           New value for the indent level (it may be equal to self.indent_spaces
         if indentation doesn't change.
 
         full_dedent : boolean
           Whether the new line causes a full flush-left dedent.
         """
         indent_spaces = self.indent_spaces
         full_dedent = self._full_dedent
 
         inisp = num_ini_spaces(line)
         if inisp < indent_spaces:
             indent_spaces = inisp
             if indent_spaces <= 0:
                 #print 'Full dedent in text',self.source # dbg
                 full_dedent = True
 
         if line.rstrip()[-1] == ':':
             indent_spaces += 4
         elif dedent_re.match(line):
             indent_spaces -= 4
             if indent_spaces <= 0:
                 full_dedent = True
 
         # Safety
         if indent_spaces < 0:
             indent_spaces = 0
             #print 'safety' # dbg
 
         return indent_spaces, full_dedent
 
     def _update_indent(self, lines):
         for line in remove_comments(lines).splitlines():
             if line and not line.isspace():
                 self.indent_spaces, self._full_dedent = self._find_indent(line)
 
     def _store(self, lines, buffer=None, store='source'):
         """Store one or more lines of input.
 
         If input lines are not newline-terminated, a newline is automatically
         appended."""
 
         if buffer is None:
             buffer = self._buffer
 
         if lines.endswith('\n'):
             buffer.append(lines)
         else:
             buffer.append(lines+'\n')
         setattr(self, store, self._set_source(buffer))
 
     def _set_source(self, buffer):
         return u''.join(buffer)
 
 
 class IPythonInputSplitter(InputSplitter):
     """An input splitter that recognizes all of IPython's special syntax."""
 
     # String with raw, untransformed input.
     source_raw = ''
     
     # Flag to track when a transformer has stored input that it hasn't given
     # back yet.
     transformer_accumulating = False
     
     # Flag to track when assemble_python_lines has stored input that it hasn't
     # given back yet.
     within_python_line = False
 
     # Private attributes
 
     # List with lines of raw input accumulated so far.
     _buffer_raw = None
 
     def __init__(self, line_input_checker=True, physical_line_transforms=None,
                     logical_line_transforms=None, python_line_transforms=None):
         super(IPythonInputSplitter, self).__init__()
         self._buffer_raw = []
         self._validate = True
         
         if physical_line_transforms is not None:
             self.physical_line_transforms = physical_line_transforms
         else:
             self.physical_line_transforms = [
                                              leading_indent(),
                                              classic_prompt(),
                                              ipy_prompt(),
                                              strip_encoding_cookie(),
                                              cellmagic(end_on_blank_line=line_input_checker),
                                             ]
         
         self.assemble_logical_lines = assemble_logical_lines()
         if logical_line_transforms is not None:
             self.logical_line_transforms = logical_line_transforms
         else:
             self.logical_line_transforms = [
                                             help_end(),
                                             escaped_commands(),
                                             assign_from_magic(),
                                             assign_from_system(),
                                            ]
         
         self.assemble_python_lines = assemble_python_lines()
         if python_line_transforms is not None:
             self.python_line_transforms = python_line_transforms
         else:
             # We don't use any of these at present
             self.python_line_transforms = []
     
     @property
     def transforms(self):
         "Quick access to all transformers."
         return self.physical_line_transforms + \
             [self.assemble_logical_lines] + self.logical_line_transforms + \
             [self.assemble_python_lines]  + self.python_line_transforms
     
     @property
     def transforms_in_use(self):
         """Transformers, excluding logical line transformers if we're in a
         Python line."""
         t = self.physical_line_transforms[:]
         if not self.within_python_line:
             t += [self.assemble_logical_lines] + self.logical_line_transforms
         return t + [self.assemble_python_lines] + self.python_line_transforms
 
     def reset(self):
         """Reset the input buffer and associated state."""
         super(IPythonInputSplitter, self).reset()
         self._buffer_raw[:] = []
         self.source_raw = ''
         self.transformer_accumulating = False
         self.within_python_line = False
 
         for t in self.transforms:
             try:
                 t.reset()
             except SyntaxError:
                 # Nothing that calls reset() expects to handle transformer
                 # errors
                 pass
     
     def flush_transformers(self):
         def _flush(transform, out):
             if out is not None:
                 tmp = transform.push(out)
                 return tmp or transform.reset() or None
             else:
                 return transform.reset() or None
         
         out = None
         for t in self.transforms_in_use:
             out = _flush(t, out)
         
         if out is not None:
             self._store(out)
 
     def raw_reset(self):
         """Return raw input only and perform a full reset.
         """
         out = self.source_raw
         self.reset()
         return out
     
     def source_reset(self):
         try:
             self.flush_transformers()
             return self.source
         finally:
             self.reset()
 
     def push_accepts_more(self):
         if self.transformer_accumulating:
             return True
         else:
             return super(IPythonInputSplitter, self).push_accepts_more()
 
     def transform_cell(self, cell):
         """Process and translate a cell of input.
         """
         self.reset()
         try:
             self.push(cell)
             self.flush_transformers()
             return self.source
         finally:
             self.reset()
 
     def push(self, lines):
         """Push one or more lines of IPython input.
 
         This stores the given lines and returns a status code indicating
         whether the code forms a complete Python block or not, after processing
         all input lines for special IPython syntax.
 
         Any exceptions generated in compilation are swallowed, but if an
         exception was produced, the method returns True.
 
         Parameters
         ----------
         lines : string
           One or more lines of Python input.
 
         Returns
         -------
         is_complete : boolean
           True if the current input source (the result of the current input
           plus prior inputs) forms a complete Python execution block.  Note that
           this value is also stored as a private attribute (_is_complete), so it
           can be queried at any time.
         """
 
         # We must ensure all input is pure unicode
         lines = cast_unicode(lines, self.encoding)
         
         # ''.splitlines() --> [], but we need to push the empty line to transformers
         lines_list = lines.splitlines()
         if not lines_list:
             lines_list = ['']
 
         # Store raw source before applying any transformations to it.  Note
         # that this must be done *after* the reset() call that would otherwise
         # flush the buffer.
         self._store(lines, self._buffer_raw, 'source_raw')
 
         for line in lines_list:
             out = self.push_line(line)
 
         return out
     
     def push_line(self, line):
         buf = self._buffer
         
         def _accumulating(dbg):
             #print(dbg)
             self.transformer_accumulating = True
             return False
         
         for transformer in self.physical_line_transforms:
             line = transformer.push(line)
             if line is None:
                 return _accumulating(transformer)
         
         if not self.within_python_line:
             line = self.assemble_logical_lines.push(line)
             if line is None:
                 return _accumulating('acc logical line')        
         
             for transformer in self.logical_line_transforms:
                 line = transformer.push(line)
                 if line is None:
                     return _accumulating(transformer)
         
         line = self.assemble_python_lines.push(line)
         if line is None:
             self.within_python_line = True
             return _accumulating('acc python line')
         else:
             self.within_python_line = False
         
         for transformer in self.python_line_transforms:
             line = transformer.push(line)
             if line is None:
                 return _accumulating(transformer)
 
         #print("transformers clear") #debug
         self.transformer_accumulating = False
         return super(IPythonInputSplitter, self).push(line)

IPython/core/tests/test_inputsplitter.py

@@ -1,585 +1,592 b''
 # -*- coding: utf-8 -*-
 """Tests for the inputsplitter module.
 
 Authors
 -------
 * Fernando Perez
 * Robert Kern
 """
 from __future__ import print_function
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2010-2011  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.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 # stdlib
 import unittest
 import sys
 
 # Third party
 import nose.tools as nt
 
 # Our own
 from IPython.core import inputsplitter as isp
 from IPython.core.tests.test_inputtransformer import syntax, syntax_ml
 from IPython.testing import tools as tt
 from IPython.utils import py3compat
 from IPython.utils.py3compat import string_types, input
 
 #-----------------------------------------------------------------------------
 # Semi-complete examples (also used as tests)
 #-----------------------------------------------------------------------------
 
 # Note: at the bottom, there's a slightly more complete version of this that
 # can be useful during development of code here.
 
 def mini_interactive_loop(input_func):
     """Minimal example of the logic of an interactive interpreter loop.
 
     This serves as an example, and it is used by the test system with a fake
     raw_input that simulates interactive input."""
 
     from IPython.core.inputsplitter import InputSplitter
 
     isp = InputSplitter()
     # In practice, this input loop would be wrapped in an outside loop to read
     # input indefinitely, until some exit/quit command was issued.  Here we
     # only illustrate the basic inner loop.
     while isp.push_accepts_more():
         indent = ' '*isp.indent_spaces
         prompt = '>>> ' + indent
         line = indent + input_func(prompt)
         isp.push(line)
 
     # Here we just return input so we can use it in a test suite, but a real
     # interpreter would instead send it for execution somewhere.
     src = isp.source_reset()
     #print 'Input source was:\n', src  # dbg
     return src
 
 #-----------------------------------------------------------------------------
 # Test utilities, just for local use
 #-----------------------------------------------------------------------------
 
 def assemble(block):
     """Assemble a block into multi-line sub-blocks."""
     return ['\n'.join(sub_block)+'\n' for sub_block in block]
 
 
 def pseudo_input(lines):
     """Return a function that acts like raw_input but feeds the input list."""
     ilines = iter(lines)
     def raw_in(prompt):
         try:
             return next(ilines)
         except StopIteration:
             return ''
     return raw_in
 
 #-----------------------------------------------------------------------------
 # Tests
 #-----------------------------------------------------------------------------
 def test_spaces():
     tests = [('', 0),
              (' ', 1),
              ('\n', 0),
              (' \n', 1),
              ('x', 0),
              (' x', 1),
              ('  x',2),
              ('    x',4),
              # Note: tabs are counted as a single whitespace!
              ('\tx', 1),
              ('\t x', 2),
              ]
     tt.check_pairs(isp.num_ini_spaces, tests)
 
 
 def test_remove_comments():
     tests = [('text', 'text'),
              ('text # comment', 'text '),
              ('text # comment\n', 'text \n'),
              ('text # comment \n', 'text \n'),
              ('line # c \nline\n','line \nline\n'),
              ('line # c \nline#c2  \nline\nline #c\n\n',
               'line \nline\nline\nline \n\n'),
              ]
     tt.check_pairs(isp.remove_comments, tests)
 
 
 def test_get_input_encoding():
     encoding = isp.get_input_encoding()
     nt.assert_true(isinstance(encoding, string_types))
     # simple-minded check that at least encoding a simple string works with the
     # encoding we got.
     nt.assert_equal(u'test'.encode(encoding), b'test')
 
 
 class NoInputEncodingTestCase(unittest.TestCase):
     def setUp(self):
         self.old_stdin = sys.stdin
         class X: pass
         fake_stdin = X()
         sys.stdin = fake_stdin
 
     def test(self):
         # Verify that if sys.stdin has no 'encoding' attribute we do the right
         # thing
         enc = isp.get_input_encoding()
         self.assertEqual(enc, 'ascii')
 
     def tearDown(self):
         sys.stdin = self.old_stdin
 
 
 class InputSplitterTestCase(unittest.TestCase):
     def setUp(self):
         self.isp = isp.InputSplitter()
 
     def test_reset(self):
         isp = self.isp
         isp.push('x=1')
         isp.reset()
         self.assertEqual(isp._buffer, [])
         self.assertEqual(isp.indent_spaces, 0)
         self.assertEqual(isp.source, '')
         self.assertEqual(isp.code, None)
         self.assertEqual(isp._is_complete, False)
 
     def test_source(self):
         self.isp._store('1')
         self.isp._store('2')
         self.assertEqual(self.isp.source, '1\n2\n')
         self.assertTrue(len(self.isp._buffer)>0)
         self.assertEqual(self.isp.source_reset(), '1\n2\n')
         self.assertEqual(self.isp._buffer, [])
         self.assertEqual(self.isp.source, '')
 
     def test_indent(self):
         isp = self.isp # shorthand
         isp.push('x=1')
         self.assertEqual(isp.indent_spaces, 0)
         isp.push('if 1:\n    x=1')
         self.assertEqual(isp.indent_spaces, 4)
         isp.push('y=2\n')
         self.assertEqual(isp.indent_spaces, 0)
 
     def test_indent2(self):
         isp = self.isp
         isp.push('if 1:')
         self.assertEqual(isp.indent_spaces, 4)
         isp.push('    x=1')
         self.assertEqual(isp.indent_spaces, 4)
         # Blank lines shouldn't change the indent level
         isp.push(' '*2)
         self.assertEqual(isp.indent_spaces, 4)
 
     def test_indent3(self):
         isp = self.isp
         # When a multiline statement contains parens or multiline strings, we
         # shouldn't get confused.
         isp.push("if 1:")
         isp.push("    x = (1+\n    2)")
         self.assertEqual(isp.indent_spaces, 4)
 
     def test_indent4(self):
         isp = self.isp
         # whitespace after ':' should not screw up indent level
         isp.push('if 1: \n    x=1')
         self.assertEqual(isp.indent_spaces, 4)
         isp.push('y=2\n')
         self.assertEqual(isp.indent_spaces, 0)
         isp.push('if 1:\t\n    x=1')
         self.assertEqual(isp.indent_spaces, 4)
         isp.push('y=2\n')
         self.assertEqual(isp.indent_spaces, 0)
 
     def test_dedent_pass(self):
         isp = self.isp # shorthand
         # should NOT cause dedent
         isp.push('if 1:\n    passes = 5')
         self.assertEqual(isp.indent_spaces, 4)
         isp.push('if 1:\n     pass')
         self.assertEqual(isp.indent_spaces, 0)
         isp.push('if 1:\n     pass   ')
         self.assertEqual(isp.indent_spaces, 0)
 
     def test_dedent_break(self):
         isp = self.isp # shorthand
         # should NOT cause dedent
         isp.push('while 1:\n    breaks = 5')
         self.assertEqual(isp.indent_spaces, 4)
         isp.push('while 1:\n     break')
         self.assertEqual(isp.indent_spaces, 0)
         isp.push('while 1:\n     break   ')
         self.assertEqual(isp.indent_spaces, 0)
 
     def test_dedent_continue(self):
         isp = self.isp # shorthand
         # should NOT cause dedent
         isp.push('while 1:\n    continues = 5')
         self.assertEqual(isp.indent_spaces, 4)
         isp.push('while 1:\n     continue')
         self.assertEqual(isp.indent_spaces, 0)
         isp.push('while 1:\n     continue   ')
         self.assertEqual(isp.indent_spaces, 0)
 
     def test_dedent_raise(self):
         isp = self.isp # shorthand
         # should NOT cause dedent
         isp.push('if 1:\n    raised = 4')
         self.assertEqual(isp.indent_spaces, 4)
         isp.push('if 1:\n     raise TypeError()')
         self.assertEqual(isp.indent_spaces, 0)
         isp.push('if 1:\n     raise')
         self.assertEqual(isp.indent_spaces, 0)
         isp.push('if 1:\n     raise      ')
         self.assertEqual(isp.indent_spaces, 0)
 
     def test_dedent_return(self):
         isp = self.isp # shorthand
         # should NOT cause dedent
         isp.push('if 1:\n    returning = 4')
         self.assertEqual(isp.indent_spaces, 4)
         isp.push('if 1:\n     return 5 + 493')
         self.assertEqual(isp.indent_spaces, 0)
         isp.push('if 1:\n     return')
         self.assertEqual(isp.indent_spaces, 0)
         isp.push('if 1:\n     return      ')
         self.assertEqual(isp.indent_spaces, 0)
         isp.push('if 1:\n     return(0)')
         self.assertEqual(isp.indent_spaces, 0)
 
     def test_push(self):
         isp = self.isp
         self.assertTrue(isp.push('x=1'))
 
     def test_push2(self):
         isp = self.isp
         self.assertFalse(isp.push('if 1:'))
         for line in ['  x=1', '# a comment', '  y=2']:
             print(line)
             self.assertTrue(isp.push(line))
 
     def test_push3(self):
         isp = self.isp
         isp.push('if True:')
         isp.push('  a = 1')
         self.assertFalse(isp.push('b = [1,'))
 
     def test_push_accepts_more(self):
         isp = self.isp
         isp.push('x=1')
         self.assertFalse(isp.push_accepts_more())
 
     def test_push_accepts_more2(self):
         isp = self.isp
         isp.push('if 1:')
         self.assertTrue(isp.push_accepts_more())
         isp.push('  x=1')
         self.assertTrue(isp.push_accepts_more())
         isp.push('')
         self.assertFalse(isp.push_accepts_more())
 
     def test_push_accepts_more3(self):
         isp = self.isp
         isp.push("x = (2+\n3)")
         self.assertFalse(isp.push_accepts_more())
 
     def test_push_accepts_more4(self):
         isp = self.isp
         # When a multiline statement contains parens or multiline strings, we
         # shouldn't get confused.
         # FIXME: we should be able to better handle de-dents in statements like
         # multiline strings and multiline expressions (continued with \ or
         # parens).  Right now we aren't handling the indentation tracking quite
         # correctly with this, though in practice it may not be too much of a
         # problem.  We'll need to see.
         isp.push("if 1:")
         isp.push("    x = (2+")
         isp.push("    3)")
         self.assertTrue(isp.push_accepts_more())
         isp.push("    y = 3")
         self.assertTrue(isp.push_accepts_more())
         isp.push('')
         self.assertFalse(isp.push_accepts_more())
 
     def test_push_accepts_more5(self):
         isp = self.isp
         isp.push('try:')
         isp.push('    a = 5')
         isp.push('except:')
         isp.push('    raise')
         # We want to be able to add an else: block at this point, so it should
         # wait for a blank line.
         self.assertTrue(isp.push_accepts_more())
 
     def test_continuation(self):
         isp = self.isp
         isp.push("import os, \\")
         self.assertTrue(isp.push_accepts_more())
         isp.push("sys")
         self.assertFalse(isp.push_accepts_more())
 
     def test_syntax_error(self):
         isp = self.isp
         # Syntax errors immediately produce a 'ready' block, so the invalid
         # Python can be sent to the kernel for evaluation with possible ipython
         # special-syntax conversion.
         isp.push('run foo')
         self.assertFalse(isp.push_accepts_more())
 
     def test_unicode(self):
         self.isp.push(u"Pérez")
         self.isp.push(u'\xc3\xa9')
         self.isp.push(u"u'\xc3\xa9'")
 
     def test_line_continuation(self):
         """ Test issue #2108."""
         isp = self.isp
         # A blank line after a line continuation should not accept more
         isp.push("1 \\\n\n")
         self.assertFalse(isp.push_accepts_more())
         # Whitespace after a \ is a SyntaxError.  The only way to test that
         # here is to test that push doesn't accept more (as with
         # test_syntax_error() above).
         isp.push(r"1 \ ")
         self.assertFalse(isp.push_accepts_more())
         # Even if the line is continuable (c.f. the regular Python
         # interpreter)
         isp.push(r"(1 \ ")
         self.assertFalse(isp.push_accepts_more())
 
+    def test_is_complete(self):
+        isp = self.isp
+        assert isp.is_complete("a = 1")
+        assert not isp.is_complete("for a in range(5):")
+        assert isp.is_complete("raise = 2")  # SyntaxError should mean complete
+        assert not isp.is_complete("a = [1,\n2,")
+
 class InteractiveLoopTestCase(unittest.TestCase):
     """Tests for an interactive loop like a python shell.
     """
     def check_ns(self, lines, ns):
         """Validate that the given input lines produce the resulting namespace.
 
         Note: the input lines are given exactly as they would be typed in an
         auto-indenting environment, as mini_interactive_loop above already does
         auto-indenting and prepends spaces to the input.
         """
         src = mini_interactive_loop(pseudo_input(lines))
         test_ns = {}
         exec(src, test_ns)
         # We can't check that the provided ns is identical to the test_ns,
         # because Python fills test_ns with extra keys (copyright, etc).  But
         # we can check that the given dict is *contained* in test_ns
         for k,v in ns.items():
             self.assertEqual(test_ns[k], v)
 
     def test_simple(self):
         self.check_ns(['x=1'], dict(x=1))
 
     def test_simple2(self):
         self.check_ns(['if 1:', 'x=2'], dict(x=2))
 
     def test_xy(self):
         self.check_ns(['x=1; y=2'], dict(x=1, y=2))
 
     def test_abc(self):
         self.check_ns(['if 1:','a=1','b=2','c=3'], dict(a=1, b=2, c=3))
 
     def test_multi(self):
         self.check_ns(['x =(1+','1+','2)'], dict(x=4))
 
 
 class IPythonInputTestCase(InputSplitterTestCase):
     """By just creating a new class whose .isp is a different instance, we
     re-run the same test battery on the new input splitter.
 
     In addition, this runs the tests over the syntax and syntax_ml dicts that
     were tested by individual functions, as part of the OO interface.
 
     It also makes some checks on the raw buffer storage.
     """
 
     def setUp(self):
         self.isp = isp.IPythonInputSplitter()
 
     def test_syntax(self):
         """Call all single-line syntax tests from the main object"""
         isp = self.isp
         for example in syntax.values():
             for raw, out_t in example:
                 if raw.startswith(' '):
                     continue
 
                 isp.push(raw+'\n')
                 out_raw = isp.source_raw
                 out = isp.source_reset()
                 self.assertEqual(out.rstrip(), out_t,
                         tt.pair_fail_msg.format("inputsplitter",raw, out_t, out))
                 self.assertEqual(out_raw.rstrip(), raw.rstrip())
 
     def test_syntax_multiline(self):
         isp = self.isp
         for example in syntax_ml.values():
             for line_pairs in example:
                 out_t_parts = []
                 raw_parts = []
                 for lraw, out_t_part in line_pairs:
                     if out_t_part is not None:
                         out_t_parts.append(out_t_part)
                     
                     if lraw is not None:
                         isp.push(lraw)
                         raw_parts.append(lraw)
 
                 out_raw = isp.source_raw
                 out = isp.source_reset()
                 out_t = '\n'.join(out_t_parts).rstrip()
                 raw = '\n'.join(raw_parts).rstrip()
                 self.assertEqual(out.rstrip(), out_t)
                 self.assertEqual(out_raw.rstrip(), raw)
 
     def test_syntax_multiline_cell(self):
         isp = self.isp
         for example in syntax_ml.values():
 
             out_t_parts = []
             for line_pairs in example:
                 raw = '\n'.join(r for r, _ in line_pairs if r is not None)
                 out_t = '\n'.join(t for _,t in line_pairs if t is not None)
                 out = isp.transform_cell(raw)
                 # Match ignoring trailing whitespace
                 self.assertEqual(out.rstrip(), out_t.rstrip())
     
     def test_cellmagic_preempt(self):
         isp = self.isp
         for raw, name, line, cell in [
             ("%%cellm a\nIn[1]:", u'cellm', u'a', u'In[1]:'),
             ("%%cellm \nline\n>>> hi", u'cellm', u'', u'line\n>>> hi'),
             (">>> %%cellm \nline\n>>> hi", u'cellm', u'', u'line\nhi'),
             ("%%cellm \n>>> hi", u'cellm', u'', u'hi'),
             ("%%cellm \nline1\nline2", u'cellm', u'', u'line1\nline2'),
             ("%%cellm \nline1\\\\\nline2", u'cellm', u'', u'line1\\\\\nline2'),
         ]:
             expected = "get_ipython().run_cell_magic(%r, %r, %r)" % (
                 name, line, cell
             )
             out = isp.transform_cell(raw)
             self.assertEqual(out.rstrip(), expected.rstrip())
         
         
 
 #-----------------------------------------------------------------------------
 # Main - use as a script, mostly for developer experiments
 #-----------------------------------------------------------------------------
 
 if __name__ == '__main__':
     # A simple demo for interactive experimentation.  This code will not get
     # picked up by any test suite.
     from IPython.core.inputsplitter import InputSplitter, IPythonInputSplitter
 
     # configure here the syntax to use, prompt and whether to autoindent
     #isp, start_prompt = InputSplitter(), '>>> '
     isp, start_prompt = IPythonInputSplitter(), 'In> '
 
     autoindent = True
     #autoindent = False
 
     try:
         while True:
             prompt = start_prompt
             while isp.push_accepts_more():
                 indent = ' '*isp.indent_spaces
                 if autoindent:
                     line = indent + input(prompt+indent)
                 else:
                     line = input(prompt)
                 isp.push(line)
                 prompt = '... '
 
             # Here we just return input so we can use it in a test suite, but a
             # real interpreter would instead send it for execution somewhere.
             #src = isp.source; raise EOFError # dbg
             raw = isp.source_raw
             src = isp.source_reset()
             print('Input source was:\n', src)
             print('Raw source was:\n', raw)
     except EOFError:
         print('Bye')
 
 # Tests for cell magics support
 
 def test_last_blank():
     nt.assert_false(isp.last_blank(''))
     nt.assert_false(isp.last_blank('abc'))
     nt.assert_false(isp.last_blank('abc\n'))
     nt.assert_false(isp.last_blank('abc\na'))
 
     nt.assert_true(isp.last_blank('\n'))
     nt.assert_true(isp.last_blank('\n '))
     nt.assert_true(isp.last_blank('abc\n '))
     nt.assert_true(isp.last_blank('abc\n\n'))
     nt.assert_true(isp.last_blank('abc\nd\n\n'))
     nt.assert_true(isp.last_blank('abc\nd\ne\n\n'))
     nt.assert_true(isp.last_blank('abc \n \n \n\n'))
 
 
 def test_last_two_blanks():
     nt.assert_false(isp.last_two_blanks(''))
     nt.assert_false(isp.last_two_blanks('abc'))
     nt.assert_false(isp.last_two_blanks('abc\n'))
     nt.assert_false(isp.last_two_blanks('abc\n\na'))
     nt.assert_false(isp.last_two_blanks('abc\n \n'))
     nt.assert_false(isp.last_two_blanks('abc\n\n'))
 
     nt.assert_true(isp.last_two_blanks('\n\n'))
     nt.assert_true(isp.last_two_blanks('\n\n '))
     nt.assert_true(isp.last_two_blanks('\n \n'))
     nt.assert_true(isp.last_two_blanks('abc\n\n '))
     nt.assert_true(isp.last_two_blanks('abc\n\n\n'))
     nt.assert_true(isp.last_two_blanks('abc\n\n \n'))
     nt.assert_true(isp.last_two_blanks('abc\n\n \n '))
     nt.assert_true(isp.last_two_blanks('abc\n\n \n \n'))
     nt.assert_true(isp.last_two_blanks('abc\nd\n\n\n'))
     nt.assert_true(isp.last_two_blanks('abc\nd\ne\nf\n\n\n'))
 
 
 class CellMagicsCommon(object):
 
     def test_whole_cell(self):
         src = "%%cellm line\nbody\n"
         out = self.sp.transform_cell(src)
         ref = u"get_ipython().run_cell_magic({u}'cellm', {u}'line', {u}'body')\n"
         nt.assert_equal(out, py3compat.u_format(ref))
     
     def test_cellmagic_help(self):
         self.sp.push('%%cellm?')
         nt.assert_false(self.sp.push_accepts_more())
 
     def tearDown(self):
         self.sp.reset()
 
 
 class CellModeCellMagics(CellMagicsCommon, unittest.TestCase):
     sp = isp.IPythonInputSplitter(line_input_checker=False)
 
     def test_incremental(self):
         sp = self.sp
         sp.push('%%cellm firstline\n')
         nt.assert_true(sp.push_accepts_more()) #1
         sp.push('line2\n')
         nt.assert_true(sp.push_accepts_more()) #2
         sp.push('\n')
         # This should accept a blank line and carry on until the cell is reset
         nt.assert_true(sp.push_accepts_more()) #3
 
 class LineModeCellMagics(CellMagicsCommon, unittest.TestCase):
     sp = isp.IPythonInputSplitter(line_input_checker=True)
 
     def test_incremental(self):
         sp = self.sp
         sp.push('%%cellm line2\n')
         nt.assert_true(sp.push_accepts_more()) #1
         sp.push('\n')
         # In this case, a blank line should end the cell magic
         nt.assert_false(sp.push_accepts_more()) #2

IPython/kernel/tests/test_kernel.py

@@ -1,207 +1,223 b''
 # coding: utf-8
 """test the IPython Kernel"""
 
 #-------------------------------------------------------------------------------
 #  Copyright (C) 2013  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.
 #-------------------------------------------------------------------------------
 
 #-------------------------------------------------------------------------------
 # Imports
 #-------------------------------------------------------------------------------
 
 import io
 import os.path
 import sys
 
 import nose.tools as nt
 
 from IPython.testing import decorators as dec, tools as tt
 from IPython.utils import py3compat
 from IPython.utils.path import locate_profile
 from IPython.utils.tempdir import TemporaryDirectory
 
 from .utils import (new_kernel, kernel, TIMEOUT, assemble_output, execute,
                     flush_channels, wait_for_idle)
 
 #-------------------------------------------------------------------------------
 # Tests
 #-------------------------------------------------------------------------------
 
 
 def _check_mp_mode(kc, expected=False, stream="stdout"):
     execute(kc=kc, code="import sys")
     flush_channels(kc)
     msg_id, content = execute(kc=kc, code="print (sys.%s._check_mp_mode())" % stream)
     stdout, stderr = assemble_output(kc.iopub_channel)
     nt.assert_equal(eval(stdout.strip()), expected)
 
 
 # printing tests
 
 def test_simple_print():
     """simple print statement in kernel"""
     with kernel() as kc:
         iopub = kc.iopub_channel
         msg_id, content = execute(kc=kc, code="print ('hi')")
         stdout, stderr = assemble_output(iopub)
         nt.assert_equal(stdout, 'hi\n')
         nt.assert_equal(stderr, '')
         _check_mp_mode(kc, expected=False)
 
 
 def test_sys_path():
     """test that sys.path doesn't get messed up by default"""
     with kernel() as kc:
         msg_id, content = execute(kc=kc, code="import sys; print (repr(sys.path[0]))")
         stdout, stderr = assemble_output(kc.iopub_channel)
         nt.assert_equal(stdout, "''\n")
 
 def test_sys_path_profile_dir():
     """test that sys.path doesn't get messed up when `--profile-dir` is specified"""
     
     with new_kernel(['--profile-dir', locate_profile('default')]) as kc:
         msg_id, content = execute(kc=kc, code="import sys; print (repr(sys.path[0]))")
         stdout, stderr = assemble_output(kc.iopub_channel)
         nt.assert_equal(stdout, "''\n")
 
 @dec.knownfailureif(sys.platform == 'win32', "subprocess prints fail on Windows")
 def test_subprocess_print():
     """printing from forked mp.Process"""
     with new_kernel() as kc:
         iopub = kc.iopub_channel
         
         _check_mp_mode(kc, expected=False)
         flush_channels(kc)
         np = 5
         code = '\n'.join([
             "from __future__ import print_function",
             "import multiprocessing as mp",
             "pool = [mp.Process(target=print, args=('hello', i,)) for i in range(%i)]" % np,
             "for p in pool: p.start()",
             "for p in pool: p.join()"
         ])
         
         expected = '\n'.join([
             "hello %s" % i for i in range(np)
         ]) + '\n'
         
         msg_id, content = execute(kc=kc, code=code)
         stdout, stderr = assemble_output(iopub)
         nt.assert_equal(stdout.count("hello"), np, stdout)
         for n in range(np):
             nt.assert_equal(stdout.count(str(n)), 1, stdout)
         nt.assert_equal(stderr, '')
         _check_mp_mode(kc, expected=False)
         _check_mp_mode(kc, expected=False, stream="stderr")
 
 
 def test_subprocess_noprint():
     """mp.Process without print doesn't trigger iostream mp_mode"""
     with kernel() as kc:
         iopub = kc.iopub_channel
         
         np = 5
         code = '\n'.join([
             "import multiprocessing as mp",
             "pool = [mp.Process(target=range, args=(i,)) for i in range(%i)]" % np,
             "for p in pool: p.start()",
             "for p in pool: p.join()"
         ])
         
         msg_id, content = execute(kc=kc, code=code)
         stdout, stderr = assemble_output(iopub)
         nt.assert_equal(stdout, '')
         nt.assert_equal(stderr, '')
 
         _check_mp_mode(kc, expected=False)
         _check_mp_mode(kc, expected=False, stream="stderr")
 
 
 @dec.knownfailureif(sys.platform == 'win32', "subprocess prints fail on Windows")
 def test_subprocess_error():
     """error in mp.Process doesn't crash"""
     with new_kernel() as kc:
         iopub = kc.iopub_channel
         
         code = '\n'.join([
             "import multiprocessing as mp",
             "p = mp.Process(target=int, args=('hi',))",
             "p.start()",
             "p.join()",
         ])
         
         msg_id, content = execute(kc=kc, code=code)
         stdout, stderr = assemble_output(iopub)
         nt.assert_equal(stdout, '')
         nt.assert_true("ValueError" in stderr, stderr)
 
         _check_mp_mode(kc, expected=False)
         _check_mp_mode(kc, expected=False, stream="stderr")
 
 # raw_input tests
 
 def test_raw_input():
     """test [raw_]input"""
     with kernel() as kc:
         iopub = kc.iopub_channel
         
         input_f = "input" if py3compat.PY3 else "raw_input"
         theprompt = "prompt> "
         code = 'print({input_f}("{theprompt}"))'.format(**locals())
         msg_id = kc.execute(code, allow_stdin=True)
         msg = kc.get_stdin_msg(block=True, timeout=TIMEOUT)
         nt.assert_equal(msg['header']['msg_type'], u'input_request')
         content = msg['content']
         nt.assert_equal(content['prompt'], theprompt)
         text = "some text"
         kc.input(text)
         reply = kc.get_shell_msg(block=True, timeout=TIMEOUT)
         nt.assert_equal(reply['content']['status'], 'ok')
         stdout, stderr = assemble_output(iopub)
         nt.assert_equal(stdout, text + "\n")
 
 
 @dec.skipif(py3compat.PY3)
 def test_eval_input():
     """test input() on Python 2"""
     with kernel() as kc:
         iopub = kc.iopub_channel
         
         input_f = "input" if py3compat.PY3 else "raw_input"
         theprompt = "prompt> "
         code = 'print(input("{theprompt}"))'.format(**locals())
         msg_id = kc.execute(code, allow_stdin=True)
         msg = kc.get_stdin_msg(block=True, timeout=TIMEOUT)
         nt.assert_equal(msg['header']['msg_type'], u'input_request')
         content = msg['content']
         nt.assert_equal(content['prompt'], theprompt)
         kc.input("1+1")
         reply = kc.get_shell_msg(block=True, timeout=TIMEOUT)
         nt.assert_equal(reply['content']['status'], 'ok')
         stdout, stderr = assemble_output(iopub)
         nt.assert_equal(stdout, "2\n")
 
 
 def test_save_history():
     # Saving history from the kernel with %hist -f was failing because of
     # unicode problems on Python 2.
     with kernel() as kc, TemporaryDirectory() as td:
         file = os.path.join(td, 'hist.out')
         execute(u'a=1', kc=kc)
         wait_for_idle(kc)
         execute(u'b=u"abcþ"', kc=kc)
         wait_for_idle(kc)
         _, reply = execute("%hist -f " + file, kc=kc)
         nt.assert_equal(reply['status'], 'ok')
         with io.open(file, encoding='utf-8') as f:
             content = f.read()
         nt.assert_in(u'a=1', content)
         nt.assert_in(u'b=u"abcþ"', content)
 
 def test_help_output():
     """ipython kernel --help-all works"""
     tt.help_all_output_test('kernel')
 
+def test_is_complete():
+    with kernel() as kc:
+        # There are more test cases for this in core - here we just check
+        # that the kernel exposes the interface correctly.
+        kc.is_complete('2+2')
+        reply = kc.get_shell_msg(block=True, timeout=TIMEOUT)
+        assert reply['content']['complete']
+
+        # SyntaxError should mean it's complete        
+        kc.is_complete('raise = 2')
+        reply = kc.get_shell_msg(block=True, timeout=TIMEOUT)
+        assert reply['content']['complete']
+        
+        kc.is_complete('a = [1,\n2,')
+        reply = kc.get_shell_msg(block=True, timeout=TIMEOUT)
+        assert not reply['content']['complete']

IPython/kernel/zmq/ipkernel.py

@@ -1,302 +1,306 b''
 """The IPython kernel implementation"""
 
 import getpass
 import sys
 import traceback
 
 from IPython.core import release
 from IPython.utils.py3compat import builtin_mod, PY3
 from IPython.utils.tokenutil import token_at_cursor
 from IPython.utils.traitlets import Instance, Type, Any
 from IPython.utils.decorators import undoc
 
 from .kernelbase import Kernel as KernelBase
 from .serialize import serialize_object, unpack_apply_message
 from .zmqshell import ZMQInteractiveShell
 
 class IPythonKernel(KernelBase):
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC')
     shell_class = Type(ZMQInteractiveShell)
 
     user_module = Any()
     def _user_module_changed(self, name, old, new):
         if self.shell is not None:
             self.shell.user_module = new
 
     user_ns = Instance(dict, args=None, allow_none=True)
     def _user_ns_changed(self, name, old, new):
         if self.shell is not None:
             self.shell.user_ns = new
             self.shell.init_user_ns()
 
     # A reference to the Python builtin 'raw_input' function.
     # (i.e., __builtin__.raw_input for Python 2.7, builtins.input for Python 3)
     _sys_raw_input = Any()
     _sys_eval_input = Any()
 
     def __init__(self, **kwargs):
         super(IPythonKernel, self).__init__(**kwargs)
 
         # Initialize the InteractiveShell subclass
         self.shell = self.shell_class.instance(parent=self,
             profile_dir = self.profile_dir,
             user_module = self.user_module,
             user_ns     = self.user_ns,
             kernel      = self,
         )
         self.shell.displayhook.session = self.session
         self.shell.displayhook.pub_socket = self.iopub_socket
         self.shell.displayhook.topic = self._topic('execute_result')
         self.shell.display_pub.session = self.session
         self.shell.display_pub.pub_socket = self.iopub_socket
         self.shell.data_pub.session = self.session
         self.shell.data_pub.pub_socket = self.iopub_socket
 
         # TMP - hack while developing
         self.shell._reply_content = None
 
         comm_msg_types = [ 'comm_open', 'comm_msg', 'comm_close' ]
         comm_manager = self.shell.comm_manager
         for msg_type in comm_msg_types:
             self.shell_handlers[msg_type] = getattr(comm_manager, msg_type)
 
     # Kernel info fields
     implementation = 'ipython'
     implementation_version = release.version
     language = 'python'
     language_version = sys.version.split()[0]
     @property
     def banner(self):
         return self.shell.banner
 
     def start(self):
         self.shell.exit_now = False
         super(IPythonKernel, self).start()
 
     def set_parent(self, ident, parent):
         """Overridden from parent to tell the display hook and output streams
         about the parent message.
         """
         super(IPythonKernel, self).set_parent(ident, parent)
         self.shell.set_parent(parent)
 
     def _forward_input(self, allow_stdin=False):
         """Forward raw_input and getpass to the current frontend.
 
         via input_request
         """
         self._allow_stdin = allow_stdin
 
         if PY3:
             self._sys_raw_input = builtin_mod.input
             builtin_mod.input = self.raw_input
         else:
             self._sys_raw_input = builtin_mod.raw_input
             self._sys_eval_input = builtin_mod.input
             builtin_mod.raw_input = self.raw_input
             builtin_mod.input = lambda prompt='': eval(self.raw_input(prompt))
         self._save_getpass = getpass.getpass
         getpass.getpass = self.getpass
 
     def _restore_input(self):
         """Restore raw_input, getpass"""
         if PY3:
             builtin_mod.input = self._sys_raw_input
         else:
             builtin_mod.raw_input = self._sys_raw_input
             builtin_mod.input = self._sys_eval_input
 
         getpass.getpass = self._save_getpass
 
     @property
     def execution_count(self):
         return self.shell.execution_count
 
     @execution_count.setter
     def execution_count(self, value):
         # Ignore the incrememnting done by KernelBase, in favour of our shell's
         # execution counter.
         pass
 
     def do_execute(self, code, silent, store_history=True,
                    user_expressions=None, allow_stdin=False):
         shell = self.shell # we'll need this a lot here
 
         self._forward_input(allow_stdin)
 
         reply_content = {}
         # FIXME: the shell calls the exception handler itself.
         shell._reply_content = None
         try:
             shell.run_cell(code, store_history=store_history, silent=silent)
         except:
             status = u'error'
             # FIXME: this code right now isn't being used yet by default,
             # because the run_cell() call above directly fires off exception
             # reporting.  This code, therefore, is only active in the scenario
             # where runlines itself has an unhandled exception.  We need to
             # uniformize this, for all exception construction to come from a
             # single location in the codbase.
             etype, evalue, tb = sys.exc_info()
             tb_list = traceback.format_exception(etype, evalue, tb)
             reply_content.update(shell._showtraceback(etype, evalue, tb_list))
         else:
             status = u'ok'
         finally:
             self._restore_input()
 
         reply_content[u'status'] = status
 
         # Return the execution counter so clients can display prompts
         reply_content['execution_count'] = shell.execution_count - 1
 
         # FIXME - fish exception info out of shell, possibly left there by
         # runlines.  We'll need to clean up this logic later.
         if shell._reply_content is not None:
             reply_content.update(shell._reply_content)
             e_info = dict(engine_uuid=self.ident, engine_id=self.int_id, method='execute')
             reply_content['engine_info'] = e_info
             # reset after use
             shell._reply_content = None
 
         if 'traceback' in reply_content:
             self.log.info("Exception in execute request:\n%s", '\n'.join(reply_content['traceback']))
 
 
         # At this point, we can tell whether the main code execution succeeded
         # or not.  If it did, we proceed to evaluate user_expressions
         if reply_content['status'] == 'ok':
             reply_content[u'user_expressions'] = \
                          shell.user_expressions(user_expressions or {})
         else:
             # If there was an error, don't even try to compute expressions
             reply_content[u'user_expressions'] = {}
 
         # Payloads should be retrieved regardless of outcome, so we can both
         # recover partial output (that could have been generated early in a
         # block, before an error) and clear the payload system always.
         reply_content[u'payload'] = shell.payload_manager.read_payload()
         # Be agressive about clearing the payload because we don't want
         # it to sit in memory until the next execute_request comes in.
         shell.payload_manager.clear_payload()
 
         return reply_content
 
     def do_complete(self, code, cursor_pos):
         txt, matches = self.shell.complete('', code, cursor_pos)
         return {'matches' : matches,
                 'cursor_end' : cursor_pos,
                 'cursor_start' : cursor_pos - len(txt),
                 'metadata' : {},
                 'status' : 'ok'}
 
     def do_inspect(self, code, cursor_pos, detail_level=0):
         name = token_at_cursor(code, cursor_pos)
         info = self.shell.object_inspect(name)
 
         reply_content = {'status' : 'ok'}
         reply_content['data'] = data = {}
         reply_content['metadata'] = {}
         reply_content['found'] = info['found']
         if info['found']:
             info_text = self.shell.object_inspect_text(
                 name,
                 detail_level=detail_level,
             )
             data['text/plain'] = info_text
 
         return reply_content
 
     def do_history(self, hist_access_type, output, raw, session=None, start=None,
                    stop=None, n=None, pattern=None, unique=False):
         if hist_access_type == 'tail':
             hist = self.shell.history_manager.get_tail(n, raw=raw, output=output,
                                                             include_latest=True)
 
         elif hist_access_type == 'range':
             hist = self.shell.history_manager.get_range(session, start, stop,
                                                         raw=raw, output=output)
 
         elif hist_access_type == 'search':
             hist = self.shell.history_manager.search(
                 pattern, raw=raw, output=output, n=n, unique=unique)
         else:
             hist = []
 
         return {'history' : list(hist)}
 
     def do_shutdown(self, restart):
         self.shell.exit_now = True
         return dict(status='ok', restart=restart)
 
+    def do_is_complete(self, code):
+        complete = self.shell.input_transformer_manager.is_complete(code)
+        return {'complete': complete}
+
     def do_apply(self, content, bufs, msg_id, reply_metadata):
         shell = self.shell
         try:
             working = shell.user_ns
 
             prefix = "_"+str(msg_id).replace("-","")+"_"
 
             f,args,kwargs = unpack_apply_message(bufs, working, copy=False)
 
             fname = getattr(f, '__name__', 'f')
 
             fname = prefix+"f"
             argname = prefix+"args"
             kwargname = prefix+"kwargs"
             resultname = prefix+"result"
 
             ns = { fname : f, argname : args, kwargname : kwargs , resultname : None }
             # print ns
             working.update(ns)
             code = "%s = %s(*%s,**%s)" % (resultname, fname, argname, kwargname)
             try:
                 exec(code, shell.user_global_ns, shell.user_ns)
                 result = working.get(resultname)
             finally:
                 for key in ns:
                     working.pop(key)
 
             result_buf = serialize_object(result,
                 buffer_threshold=self.session.buffer_threshold,
                 item_threshold=self.session.item_threshold,
             )
 
         except:
             # invoke IPython traceback formatting
             shell.showtraceback()
             # FIXME - fish exception info out of shell, possibly left there by
             # run_code.  We'll need to clean up this logic later.
             reply_content = {}
             if shell._reply_content is not None:
                 reply_content.update(shell._reply_content)
                 e_info = dict(engine_uuid=self.ident, engine_id=self.int_id, method='apply')
                 reply_content['engine_info'] = e_info
                 # reset after use
                 shell._reply_content = None
 
             self.send_response(self.iopub_socket, u'error', reply_content,
                                 ident=self._topic('error'))
             self.log.info("Exception in apply request:\n%s", '\n'.join(reply_content['traceback']))
             result_buf = []
 
             if reply_content['ename'] == 'UnmetDependency':
                 reply_metadata['dependencies_met'] = False
         else:
             reply_content = {'status' : 'ok'}
 
         return reply_content, result_buf
 
     def do_clear(self):
         self.shell.reset(False)
         return dict(status='ok')
 
 
 # This exists only for backwards compatibility - use IPythonKernel instead
 
 @undoc
 class Kernel(IPythonKernel):
     def __init__(self, *args, **kwargs):
         import warnings
         warnings.warn('Kernel is a deprecated alias of IPython.kernel.zmq.ipkernel.IPythonKernel',
                       DeprecationWarning)
         super(Kernel, self).__init__(*args, **kwargs)
  No newline at end of file