Better support compiling cells with separate __future__ environments

IPython/core/compilerop.py

@@ -90,7 +90,7 b' class CachingCompiler(codeop.Compile):'
         # Now, we must monkeypatch the linecache directly so that parts of the
         # stdlib that call it outside our control go through our codepath
         # (otherwise we'd lose our tracebacks).
-        linecache.checkcache = self.check_cache
+        linecache.checkcache = check_linecache_ipython
         
     def ast_parse(self, source, filename='<unknown>', symbol='exec'):
         """Parse code to an AST with the current compiler flags active.
@@ -134,7 +134,7 b' class CachingCompiler(codeop.Compile):'
         linecache._ipython_cache[name] = entry
         return name
 
-    def check_cache(self, *args):
+def check_linecache_ipython(*args):
         """Call linecache.checkcache() safely protecting our cached values.
         """
         # First call the orignal checkcache as intended

IPython/core/interactiveshell.py

@@ -41,7 +41,7 b' from IPython.core import ultratb'
 from IPython.core.alias import AliasManager, AliasError
 from IPython.core.autocall import ExitAutocall
 from IPython.core.builtin_trap import BuiltinTrap
-from IPython.core.compilerop import CachingCompiler
+from IPython.core.compilerop import CachingCompiler, check_linecache_ipython
 from IPython.core.display_trap import DisplayTrap
 from IPython.core.displayhook import DisplayHook
 from IPython.core.displaypub import DisplayPublisher
@@ -1532,7 +1532,7 b' class InteractiveShell(SingletonConfigurable):'
         self.InteractiveTB = ultratb.AutoFormattedTB(mode = 'Plain',
                                                      color_scheme='NoColor',
                                                      tb_offset = 1,
-                                   check_cache=self.compile.check_cache)
+                                   check_cache=check_linecache_ipython)
 
         # The instance will store a pointer to the system-wide exception hook,
         # so that runtime code (such as magics) can access it.  This is because
@@ -2587,12 +2587,7 b' class InteractiveShell(SingletonConfigurable):'
         # Our own compiler remembers the __future__ environment. If we want to
         # run code with a separate __future__ environment, use the default
         # compiler
-        if shell_futures:
-            compiler = self.compile
-            ast_parse = self.compile.ast_parse
-        else:
-            compiler = compile
-            ast_parse = ast.parse
+        compiler = self.compile if shell_futures else CachingCompiler()
 
         with self.builtin_trap:
             prefilter_failed = False
@@ -2622,7 +2617,7 b' class InteractiveShell(SingletonConfigurable):'
 
                 with self.display_trap:
                     try:
-                        code_ast = ast_parse(cell, filename=cell_name)
+                        code_ast = compiler.ast_parse(cell, filename=cell_name)
                     except IndentationError:
                         self.showindentationerror()
                         if store_history:

IPython/core/tests/test_compilerop.py

@@ -67,7 +67,7 b' def test_compiler_check_cache():'
     cp = compilerop.CachingCompiler()
     cp.cache('x=1', 99)
     # Ensure now that after clearing the cache, our entries survive
-    cp.check_cache()
+    linecache.checkcache()
     for k in linecache.cache:
         if k.startswith('<ipython-input-99'):
             break