tests/test-bad-extension.t

extdiff: prepare sections of dodiff() for conditionalizing

This is purely indenting under an unconditional branch, so that the actual
changes in the next patch are clear.  Feel free to fold them if desired.

  $ 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
  *** failed to import extension badext from $TESTTMP/badext.py: bit bucket overflow
  *** failed to import extension badext2: No module named badext2
  hg help [-ec] [TOPIC]
  
  show help for a given topic or a help overview

show traceback

  $ hg -q help help --traceback 2>&1 | grep -v '^  '
  *** 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
  hg help [-ec] [TOPIC]
  
  show help for a given topic or a help overview

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

  $ hg help help --traceback --config ui.debug=True 2>&1 \
  > | grep -v '^  ' | head -n10
  *** 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
  hg help [-ec] [TOPIC]