view tests/test-bad-extension.t @ 27279:40eb385f798f

tests: add test for Python 3 compatibility

Python 3 is inevitable. There have been incremental movements towards
converting the code base to be Python 3 compatible. Unfortunately, we
don't have any tests that look for Python 3 compatibility. This patch
changes that.

We introduce a check-py3-compat.py script whose role is to verify
Python 3 compatibility of the files passed in. We add a test that
calls this script with all .py files from the source checkout.

The script currently only verifies that absolute_import and
print_function are used. These are the low hanging fruits for Python
compatbility. Over time, we can include more checks, including
verifying we're able to load each Python file with Python 3. You
have to start somewhere.

Accepting this patch means that all new .py files must have
absolute_import and print_function (if "print" is used) to avoid
a new warning about Python 3 incompatibility. We've already
converted several files to use absolute_import and print_function
is in the same boat, so I don't think this is such a radical
proposition.

  $ echo 'raise Exception("bit bucket overflow")' > badext.py
  $ abspath=`pwd`/badext.py

  $ cat <<EOF >> $HGRCPATH
  > [extensions]
  > gpg =
  > hgext.gpg =
  > badext = $abspath
  > badext2 =
  > EOF

  $ hg -q help help 2>&1 |grep extension
  *** failed to import extension badext from $TESTTMP/badext.py: bit bucket overflow
  *** failed to import extension badext2: No module named badext2

show traceback

  $ hg -q help help --traceback 2>&1 | egrep ' extension|^Exception|Traceback|ImportError'
  *** failed to import extension badext from $TESTTMP/badext.py: bit bucket overflow
  Traceback (most recent call last):
  Exception: bit bucket overflow
  *** failed to import extension badext2: No module named badext2
  Traceback (most recent call last):
  ImportError: No module named badext2

show traceback for ImportError of hgext.name if debug is set
(note that --debug option isn't applied yet when loading extensions)

  $ (hg -q help help --traceback --config ui.debug=True 2>&1) \
  > | grep -v '^ ' \
  > | egrep 'extension..[^p]|^Exception|Traceback|ImportError|not import'
  *** failed to import extension badext from $TESTTMP/badext.py: bit bucket overflow
  Traceback (most recent call last):
  Exception: bit bucket overflow
  could not import hgext.badext2 (No module named badext2): trying badext2
  Traceback (most recent call last):
  ImportError: No module named badext2
  *** failed to import extension badext2: No module named badext2
  Traceback (most recent call last):
  ImportError: No module named badext2