py3: don't run source transformer on hgext3rd (extensions)
authorMartin von Zweigbergk <martinvonz@google.com>
Sun, 07 Jul 2019 23:04:55 -0700
changeset 42574 d28d91f9f35a
parent 42573 9ac1a5a4a64f
child 42575 eec65b706caf
py3: don't run source transformer on hgext3rd (extensions) It's unclear why the source transformer runs on hgext3rd. It's been like that since it was introduced in 1c22400db72d (mercurial: implement a source transforming module loader on Python 3, 2016-07-04), and that commit didn't say anything about it (but it says that it doesn't have "support [...] for extensions"). I find that the current handling of hgext3rd just makes it harder to convert extensions to Python 3. It makes you convert a bunch of strings passed to getattr() and kwargs[] to r'' that could otherwise have been left alone. It's also really confusing that the source transformer runs when you import the extension as "extensions.foo=", but not as "extension.foo=/some/path". I suppose there is small number of (very simple) extensions that would have worked without this patch that would now be broken. It seems okay to me to break those. Differential Revision: https://phab.mercurial-scm.org/D6614
mercurial/__init__.py
relnotes/next
--- a/mercurial/__init__.py	Mon Jul 08 13:10:34 2019 -0700
+++ b/mercurial/__init__.py	Sun Jul 07 23:04:55 2019 -0700
@@ -29,7 +29,7 @@
         """A sys.meta_path finder that uses a custom module loader."""
         def find_spec(self, fullname, path, target=None):
             # Only handle Mercurial-related modules.
-            if not fullname.startswith(('mercurial.', 'hgext.', 'hgext3rd.')):
+            if not fullname.startswith(('mercurial.', 'hgext.')):
                 return None
             # don't try to parse binary
             if fullname.startswith('mercurial.cext.'):
--- a/relnotes/next	Mon Jul 08 13:10:34 2019 -0700
+++ b/relnotes/next	Sun Jul 07 23:04:55 2019 -0700
@@ -73,3 +73,7 @@
    `addunfinished()` in `state` module.
 
  * `cmdutil.checkunfinished()` now includes detection for merge too.
+
+ * We used to automatically attempt to make extensions compatible with
+   Python 3 (by translating their source code while loading it). We no
+   longer do that.