mirror of
https://github.com/python/cpython.git
synced 2025-11-03 23:21:29 +00:00
126 lines
3.4 KiB
Python
126 lines
3.4 KiB
Python
"""An Python re-implementation of hierarchical module import.
|
|
|
|
This code is intended to be read, not executed. However, it does work
|
|
-- all you need to do to enable it is "import knee".
|
|
|
|
(The name is a pun on the klunkier predecessor of this module, "ni".)
|
|
|
|
"""
|
|
|
|
import sys, imp, __builtin__, string
|
|
|
|
|
|
# Replacement for __import__()
|
|
def import_hook(name, globals=None, locals=None, fromlist=None):
|
|
parent = determine_parent(globals)
|
|
q, tail = find_head_package(parent, name)
|
|
m = load_tail(q, tail)
|
|
if not fromlist:
|
|
return q
|
|
if hasattr(m, "__path__"):
|
|
ensure_fromlist(m, fromlist)
|
|
return m
|
|
|
|
def determine_parent(globals):
|
|
if not globals or not globals.has_key("__name__"):
|
|
return None
|
|
pname = globals['__name__']
|
|
if globals.has_key("__path__"):
|
|
parent = sys.modules[pname]
|
|
assert globals is parent.__dict__
|
|
return parent
|
|
if '.' in pname:
|
|
i = string.rfind(pname, '.')
|
|
pname = pname[:i]
|
|
parent = sys.modules[pname]
|
|
assert parent.__name__ == pname
|
|
return parent
|
|
return None
|
|
|
|
def find_head_package(parent, name):
|
|
if '.' in name:
|
|
i = string.find(name, '.')
|
|
head = name[:i]
|
|
tail = name[i+1:]
|
|
else:
|
|
head = name
|
|
tail = ""
|
|
if parent:
|
|
qname = "%s.%s" % (parent.__name__, head)
|
|
else:
|
|
qname = head
|
|
q = import_module(head, qname, parent)
|
|
if q: return q, tail
|
|
if parent:
|
|
qname = head
|
|
parent = None
|
|
q = import_module(head, qname, parent)
|
|
if q: return q, tail
|
|
raise ImportError, "No module named " + qname
|
|
|
|
def load_tail(q, tail):
|
|
m = q
|
|
while tail:
|
|
i = string.find(tail, '.')
|
|
if i < 0: i = len(tail)
|
|
head, tail = tail[:i], tail[i+1:]
|
|
mname = "%s.%s" % (m.__name__, head)
|
|
m = import_module(head, mname, m)
|
|
if not m:
|
|
raise ImportError, "No module named " + mname
|
|
return m
|
|
|
|
def ensure_fromlist(m, fromlist, recursive=0):
|
|
for sub in fromlist:
|
|
if sub == "*":
|
|
if not recursive:
|
|
try:
|
|
all = m.__all__
|
|
except AttributeError:
|
|
pass
|
|
else:
|
|
ensure_fromlist(m, all, 1)
|
|
continue
|
|
if sub != "*" and not hasattr(m, sub):
|
|
subname = "%s.%s" % (m.__name__, sub)
|
|
submod = import_module(sub, subname, m)
|
|
if not submod:
|
|
raise ImportError, "No module named " + subname
|
|
|
|
def import_module(partname, fqname, parent):
|
|
try:
|
|
return sys.modules[fqname]
|
|
except KeyError:
|
|
pass
|
|
try:
|
|
fp, pathname, stuff = imp.find_module(partname,
|
|
parent and parent.__path__)
|
|
except ImportError:
|
|
return None
|
|
try:
|
|
m = imp.load_module(fqname, fp, pathname, stuff)
|
|
finally:
|
|
if fp: fp.close()
|
|
if parent:
|
|
setattr(parent, partname, m)
|
|
return m
|
|
|
|
|
|
# Replacement for reload()
|
|
def reload_hook(module):
|
|
name = module.__name__
|
|
if '.' not in name:
|
|
return import_module(name, name, None)
|
|
i = string.rfind(name, '.')
|
|
pname = name[:i]
|
|
parent = sys.modules[pname]
|
|
return import_module(name[i+1:], name, parent)
|
|
|
|
|
|
# Save the original hooks
|
|
original_import = __builtin__.__import__
|
|
original_reload = __builtin__.reload
|
|
|
|
# Now install our hooks
|
|
__builtin__.__import__ = import_hook
|
|
__builtin__.reload = reload_hook
|