[hooks/syncschema] only call "ALTER TABLE" once when changing a size constraint
Until now we would:
- remove the old size constraint from the in-memory schema
- call update_rdef_column which removes the size restriction from the
column's type
- add the new constraint object
- call update_rdef_column which adds the size restriction back
This breaks on SQL Server when the column is involved in an index (e.g.
as part of a multi-column unique constraint), because in the
intermediate stage the column's type is "nvarchar(max)", which is not
indexable.
Of course we must still detect the case where a size constraint is
really dropped and update the db schema accordingly.
Closes #5557633.
"""https://pastebin.logilab.fr/show/860/"""
from astroid import MANAGER, InferenceError, nodes, scoped_nodes
from astroid.builder import AstroidBuilder
def turn_function_to_class(node):
"""turn a Function node into a Class node (in-place)"""
node.__class__ = scoped_nodes.Class
node.bases = ()
# remove return nodes so that we don't get warned about 'return outside
# function' by pylint
for rnode in node.nodes_of_class(nodes.Return):
rnode.parent.body.remove(rnode)
# that seems to be enough :)
def cubicweb_transform(module):
# handle objectify_predicate decorator (and its former name until bw compat
# is kept). Only look at module level functions, should be enough.
for assnodes in module.locals.itervalues():
for node in assnodes:
if isinstance(node, scoped_nodes.Function) and node.decorators:
for decorator in node.decorators.nodes:
try:
for infered in decorator.infer():
if infered.name in ('objectify_predicate', 'objectify_selector'):
turn_function_to_class(node)
break
else:
continue
break
except InferenceError:
continue
# add yams base types into 'yams.buildobjs', astng doesn't grasp globals()
# magic in there
if module.name == 'yams.buildobjs':
from yams import BASE_TYPES
for etype in BASE_TYPES:
module.locals[etype] = [scoped_nodes.Class(etype, None)]
# add data() to uiprops module
if module.name.split('.')[-1] == 'uiprops':
fake = AstroidBuilder(MANAGER).string_build('''
def data(string):
return u''
''')
module.locals['data'] = fake.locals['data']
def register(linter):
"""called when loaded by pylint --load-plugins, nothing to do here"""
MANAGER.register_transform(nodes.Module, cubicweb_transform)