Also catch SyntaxErrors from InputTransformers in run_cell()

The run_cell() method is not used in the IPython terminal, so there
are two code paths where the SyntaxError needs to be caught.  Also,
this commit moves the terminal test to IPython/terminal/test/ instead
of IPython/app/test. I've checked that this works in the terminal, the
Qt console, and the html notebook.

IPython/terminal/tests/test_terminal.py

@@ -0,0 +1,58 b''
+# coding: utf-8
+"""Tests for the IPython terminal"""
+
+import os
+import tempfile
+import shutil
+
+import nose.tools as nt
+
+from IPython.testing.tools import make_tempfile, ipexec
+
+
+TEST_SYNTAX_ERROR_CMDS = """
+from IPython.core.inputtransformer import InputTransformer
+
+%cpaste
+class SyntaxErrorTransformer(InputTransformer):
+
+    def push(self, line):
+        pos = line.find('syntaxerror')
+        if pos >= 0:
+            e = SyntaxError('input contains "syntaxerror"')
+            e.text = line
+            e.offset = pos + 1
+            raise e
+        return line
+
+    def reset(self):
+        pass
+--
+
+ip = get_ipython()
+transformer = SyntaxErrorTransformer()
+ip.input_splitter.python_line_transforms.append(transformer)
+ip.input_transformer_manager.python_line_transforms.append(transformer)
+
+# now the actual commands
+1234
+2345  # syntaxerror <- triggered here
+3456
+"""
+
+def test_syntax_error():
+    """Check that the IPython terminal does not abort if a SyntaxError is raised in an InputTransformer"""
+    try:
+        tmp = tempfile.mkdtemp()
+        filename = os.path.join(tmp, 'test_syntax_error.py')
+        with open(filename, 'w') as f:
+            f.write(TEST_SYNTAX_ERROR_CMDS)
+        out, err = ipexec(filename, pipe=True)
+        nt.assert_equal(err, '')
+        nt.assert_in('1234', out)
+        nt.assert_in('    2345  # syntaxerror <- triggered here', out)
+        nt.assert_in('            ^', out)
+        nt.assert_in('SyntaxError: input contains "syntaxerror"', out)
+        nt.assert_in('3456', out)
+    finally:
+        shutil.rmtree(tmp)

IPython/core/inputtransformer.py

@@ -47,6 +47,9 b' class InputTransformer(with_metaclass(abc.ABCMeta, object)):'
         input or None if the transformer is waiting for more input.
         
         Must be overridden by subclasses.
+
+        Implementations may raise ``SyntaxError`` if the input is invalid. No
+        other exceptions may be raised.
         """
         pass
     

IPython/core/interactiveshell.py

@@ -2632,7 +2632,12 b' class InteractiveShell(SingletonConfigurable):'
         if silent:
             store_history = False
 
-        self.input_transformer_manager.push(raw_cell)
+        prefilter_failed = False
+        try:
+            self.input_transformer_manager.push(raw_cell)
+        except SyntaxError:
+            self.showtraceback()
+            prefilter_failed = True
         cell = self.input_transformer_manager.source_reset()
 
         # Our own compiler remembers the __future__ environment. If we want to
@@ -2641,8 +2646,7 b' class InteractiveShell(SingletonConfigurable):'
         compiler = self.compile if shell_futures else CachingCompiler()
 
         with self.builtin_trap:
-            prefilter_failed = False
-            if len(cell.splitlines()) == 1:
+            if not prefilter_failed and len(cell.splitlines()) == 1:
                 try:
                     # use prefilter_lines to handle trailing newlines
                     # restore trailing newline for ast.parse

IPython/core/tests/test_application.py

@@ -3,13 +3,9 b''
 
 import os
 import tempfile
-import shutil
-
-import nose.tools as nt
 
 from IPython.core.application import BaseIPythonApplication
 from IPython.testing import decorators as dec
-from IPython.testing.tools import make_tempfile, ipexec
 from IPython.utils import py3compat
 
 @dec.onlyif_unicode_paths
@@ -52,46 +48,3 b' def test_unicode_ipdir():'
             os.environ["IPYTHONDIR"] = old_ipdir1
         if old_ipdir2:
             os.environ["IPYTHONDIR"] = old_ipdir2
-
-
-
-TEST_SYNTAX_ERROR_CMDS = """
-from IPython.core.inputtransformer import InputTransformer
-
-%cpaste
-class SyntaxErrorTransformer(InputTransformer):
-
-    def push(self, line):
-        if 'syntaxerror' in line:
-            raise SyntaxError('in input '+line)
-        return line
-
-    def reset(self):
-        pass
---
-
-ip = get_ipython()
-transformer = SyntaxErrorTransformer()
-ip.input_splitter.python_line_transforms.append(transformer)
-ip.input_transformer_manager.python_line_transforms.append(transformer)
-
-# now the actual commands
-1234
-2345  # syntaxerror <- triggered here
-3456
-"""
-
-def test_syntax_error():
-    """Check that IPython does not abort if a SyntaxError is raised in an InputTransformer"""
-    try:
-        tmp = tempfile.mkdtemp()
-        filename = os.path.join(tmp, 'test_syntax_error.py')
-        with open(filename, 'w') as f:
-            f.write(TEST_SYNTAX_ERROR_CMDS)
-        out, err = ipexec(filename, pipe=True)
-        nt.assert_equal(err, '')
-        nt.assert_in('1234', out)
-        nt.assert_in('SyntaxError: in input 2345  # syntaxerror <- triggered here', out)
-        nt.assert_in('3456', out)
-    finally:
-        shutil.rmtree(tmp)

IPython/core/tests/test_interactiveshell.py

@@ -33,6 +33,7 b' from os.path import join'
 import nose.tools as nt
 
 # Our own
+from IPython.core.inputtransformer import InputTransformer
 from IPython.testing.decorators import skipif, skip_win32, onlyif_unicode_paths
 from IPython.testing import tools as tt
 from IPython.utils import io
@@ -674,4 +675,41 b' def test_user_expression():'
 
 
 
+class TestSyntaxErrorTransformer(unittest.TestCase):
+    """Check that SyntaxError raised by an input transformer is handled by run_cell()"""
+
+    class SyntaxErrorTransformer(InputTransformer):
+
+        def push(self, line):
+            pos = line.find('syntaxerror')
+            if pos >= 0:
+                e = SyntaxError('input contains "syntaxerror"')
+                e.text = line
+                e.offset = pos + 1
+                raise e
+            return line
+
+        def reset(self):
+            pass
+
+    def setUp(self):
+        self.transformer = TestSyntaxErrorTransformer.SyntaxErrorTransformer()
+        ip.input_splitter.python_line_transforms.append(self.transformer)
+        ip.input_transformer_manager.python_line_transforms.append(self.transformer)
+
+    def tearDown(self):
+        ip.input_splitter.python_line_transforms.remove(self.transformer)
+        ip.input_transformer_manager.python_line_transforms.remove(self.transformer)
+
+    def test_syntaxerror_input_transformer(self):
+        with tt.AssertPrints('1234'):
+            ip.run_cell('1234')
+        with tt.AssertPrints('SyntaxError: invalid syntax'):
+            ip.run_cell('1 2 3')   # plain python syntax error
+        with tt.AssertPrints('SyntaxError: input contains "syntaxerror"'):
+            ip.run_cell('2345  # syntaxerror')  # input transformer syntax error
+        with tt.AssertPrints('3456'):
+            ip.run_cell('3456')
+
+