Merge pull request #1544 from Carreau/fix-importhook

Fix importhook

news/imphook.rst

@@ -0,0 +1,21 @@
+**Added:** None
+
+**Changed:**
+
+* ``xonsh.imphooks`` does not install the import hooks automatically, you now
+  need to explicitly call the  `install_hook()` method defined in this module.
+  For example: ``from xonsh.imphooks import install_hook; install_hook()``. The
+  ``install_hook`` method can safely be called several times. If you need
+  compatibility with previous versions of Xonsh you can use the following::
+
+    from xonsh import imphooks
+    getattr(imphooks, 'install_hook', lambda:None)()
+
+
+**Deprecated:** None
+
+**Removed:** None
+
+**Fixed:** None
+
+**Security:** None

tests/test_imphooks.py

@@ -2,13 +2,13 @@
 """Testing xonsh import hooks"""
 import pytest
 
-from xonsh import imphooks  # noqa
-from xonsh import built_ins
+from xonsh import imphooks
 from xonsh.environ import Env
-from xonsh.execer import Execer
 from xonsh.built_ins import load_builtins, unload_builtins
 import builtins
 
+imphooks.install_hook()
+
 
 @pytest.yield_fixture(autouse=True)
 def imp_env(xonsh_execer):

tests/test_xontribs.py

@@ -53,4 +53,16 @@ _foobar = 3
 """)
 
     ctx = xontrib_context('spameggs')
-    assert ctx == {'spam': 1, '_foobar': 3}
+    assert ctx == {'spam': 1, '_foobar': 3}
+
+def test_xshxontrib(tmpmod):
+    """
+    Test that .xsh xontribs are loadable
+    """
+    with tmpmod.mkdir("xontrib").join("script.xsh").open('w') as x:
+        x.write("""
+hello = 'world'
+""")
+
+    ctx = xontrib_context('script')
+    assert ctx == {'hello': 'world'}

xonsh/imphooks.py

@@ -84,4 +84,14 @@ class XonshImportHook(MetaPathFinder, SourceLoader):
         return code
 
 
-sys.meta_path.append(XonshImportHook())
+def install_hook():
+    """
+    Install Xonsh import hook in `sys.metapath` in order for `.xsh` files to be
+    importable.
+
+    Can safely be called many times, will be no-op if a xonsh import hook is
+    already present.
+    """
+
+    if XonshImportHook not in {type(hook) for hook in sys.meta_path}:
+        sys.meta_path.append(XonshImportHook())

xonsh/main.py

@@ -18,6 +18,7 @@ from xonsh.platform import HAS_PYGMENTS, ON_WINDOWS
 from xonsh.codecache import run_script_with_cache, run_code_with_cache
 from xonsh.xonfig import xonfig_main
 from xonsh.lazyimps import pygments, pyghooks
+from xonsh.imphooks import install_hook
 
 
 def get_setproctitle():
@@ -188,6 +189,7 @@ def premain(argv=None):
         args.mode = XonshMode.interactive
         shell_kwargs['completer'] = True
         shell_kwargs['login'] = True
+    install_hook()
     builtins.__xonsh_shell__ = Shell(**shell_kwargs)
     env = builtins.__xonsh_env__
     env['XONSH_LOGIN'] = shell_kwargs['login']