qapi/introspect.py: guard against ifcond/comment misuse

_tree_to_qlit is called recursively on dict values (isolated from their
keys); at such a point in generating output it is too late to apply an
ifcond. Similarly, comments do not necessarily have a "tidy" place they
can be printed in such a circumstance.

Forbid this usage by renaming "suppress_first_indent" to "dict_value" to
emphasize that indents are suppressed only for the benefit of dict
values; then add an assertion assuring we do not pass ifcond/comments
in this case.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210216021809.134886-6-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Comment wrapped to conform to PEP 8]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This commit is contained in:
John Snow 2021-02-15 21:17:55 -05:00 committed by Markus Armbruster
parent 84bece7dd4
commit 055569603d

View File

@ -34,7 +34,7 @@ def _make_tree(obj, ifcond, extra=None):
return obj
def _tree_to_qlit(obj, level=0, suppress_first_indent=False):
def _tree_to_qlit(obj, level=0, dict_value=False):
def indent(level):
return level * 4 * ' '
@ -43,6 +43,13 @@ def _tree_to_qlit(obj, level=0, suppress_first_indent=False):
ifobj, extra = obj
ifcond = extra.get('if')
comment = extra.get('comment')
# NB: _tree_to_qlit is called recursively on the values of a
# key:value pair; those values can't be decorated with
# comments or conditionals.
msg = "dict values cannot have attached comments or if-conditionals."
assert not dict_value, msg
ret = ''
if comment:
ret += indent(level) + '/* %s */\n' % comment
@ -54,7 +61,7 @@ def _tree_to_qlit(obj, level=0, suppress_first_indent=False):
return ret
ret = ''
if not suppress_first_indent:
if not dict_value:
ret += indent(level)
if obj is None:
ret += 'QLIT_QNULL'