mirror of
https://github.com/thegeeklab/ansible-later.git
synced 2024-11-16 10:00:39 +00:00
339 lines
10 KiB
Python
339 lines
10 KiB
Python
|
#-----------------------------------------------------------------
|
||
|
# _ast_gen.py
|
||
|
#
|
||
|
# Generates the AST Node classes from a specification given in
|
||
|
# a configuration file
|
||
|
#
|
||
|
# The design of this module was inspired by astgen.py from the
|
||
|
# Python 2.5 code-base.
|
||
|
#
|
||
|
# Eli Bendersky [https://eli.thegreenplace.net/]
|
||
|
# License: BSD
|
||
|
#-----------------------------------------------------------------
|
||
|
import pprint
|
||
|
from string import Template
|
||
|
|
||
|
|
||
|
class ASTCodeGenerator(object):
|
||
|
def __init__(self, cfg_filename='_c_ast.cfg'):
|
||
|
""" Initialize the code generator from a configuration
|
||
|
file.
|
||
|
"""
|
||
|
self.cfg_filename = cfg_filename
|
||
|
self.node_cfg = [NodeCfg(name, contents)
|
||
|
for (name, contents) in self.parse_cfgfile(cfg_filename)]
|
||
|
|
||
|
def generate(self, file=None):
|
||
|
""" Generates the code into file, an open file buffer.
|
||
|
"""
|
||
|
src = Template(_PROLOGUE_COMMENT).substitute(
|
||
|
cfg_filename=self.cfg_filename)
|
||
|
|
||
|
src += _PROLOGUE_CODE
|
||
|
for node_cfg in self.node_cfg:
|
||
|
src += node_cfg.generate_source() + '\n\n'
|
||
|
|
||
|
file.write(src)
|
||
|
|
||
|
def parse_cfgfile(self, filename):
|
||
|
""" Parse the configuration file and yield pairs of
|
||
|
(name, contents) for each node.
|
||
|
"""
|
||
|
with open(filename, "r") as f:
|
||
|
for line in f:
|
||
|
line = line.strip()
|
||
|
if not line or line.startswith('#'):
|
||
|
continue
|
||
|
colon_i = line.find(':')
|
||
|
lbracket_i = line.find('[')
|
||
|
rbracket_i = line.find(']')
|
||
|
if colon_i < 1 or lbracket_i <= colon_i or rbracket_i <= lbracket_i:
|
||
|
raise RuntimeError("Invalid line in %s:\n%s\n" % (filename, line))
|
||
|
|
||
|
name = line[:colon_i]
|
||
|
val = line[lbracket_i + 1:rbracket_i]
|
||
|
vallist = [v.strip() for v in val.split(',')] if val else []
|
||
|
yield name, vallist
|
||
|
|
||
|
|
||
|
class NodeCfg(object):
|
||
|
""" Node configuration.
|
||
|
|
||
|
name: node name
|
||
|
contents: a list of contents - attributes and child nodes
|
||
|
See comment at the top of the configuration file for details.
|
||
|
"""
|
||
|
|
||
|
def __init__(self, name, contents):
|
||
|
self.name = name
|
||
|
self.all_entries = []
|
||
|
self.attr = []
|
||
|
self.child = []
|
||
|
self.seq_child = []
|
||
|
|
||
|
for entry in contents:
|
||
|
clean_entry = entry.rstrip('*')
|
||
|
self.all_entries.append(clean_entry)
|
||
|
|
||
|
if entry.endswith('**'):
|
||
|
self.seq_child.append(clean_entry)
|
||
|
elif entry.endswith('*'):
|
||
|
self.child.append(clean_entry)
|
||
|
else:
|
||
|
self.attr.append(entry)
|
||
|
|
||
|
def generate_source(self):
|
||
|
src = self._gen_init()
|
||
|
src += '\n' + self._gen_children()
|
||
|
src += '\n' + self._gen_iter()
|
||
|
|
||
|
src += '\n' + self._gen_attr_names()
|
||
|
return src
|
||
|
|
||
|
def _gen_init(self):
|
||
|
src = "class %s(Node):\n" % self.name
|
||
|
|
||
|
if self.all_entries:
|
||
|
args = ', '.join(self.all_entries)
|
||
|
slots = ', '.join("'{0}'".format(e) for e in self.all_entries)
|
||
|
slots += ", 'coord', '__weakref__'"
|
||
|
arglist = '(self, %s, coord=None)' % args
|
||
|
else:
|
||
|
slots = "'coord', '__weakref__'"
|
||
|
arglist = '(self, coord=None)'
|
||
|
|
||
|
src += " __slots__ = (%s)\n" % slots
|
||
|
src += " def __init__%s:\n" % arglist
|
||
|
|
||
|
for name in self.all_entries + ['coord']:
|
||
|
src += " self.%s = %s\n" % (name, name)
|
||
|
|
||
|
return src
|
||
|
|
||
|
def _gen_children(self):
|
||
|
src = ' def children(self):\n'
|
||
|
|
||
|
if self.all_entries:
|
||
|
src += ' nodelist = []\n'
|
||
|
|
||
|
for child in self.child:
|
||
|
src += (
|
||
|
' if self.%(child)s is not None:' +
|
||
|
' nodelist.append(("%(child)s", self.%(child)s))\n') % (
|
||
|
dict(child=child))
|
||
|
|
||
|
for seq_child in self.seq_child:
|
||
|
src += (
|
||
|
' for i, child in enumerate(self.%(child)s or []):\n'
|
||
|
' nodelist.append(("%(child)s[%%d]" %% i, child))\n') % (
|
||
|
dict(child=seq_child))
|
||
|
|
||
|
src += ' return tuple(nodelist)\n'
|
||
|
else:
|
||
|
src += ' return ()\n'
|
||
|
|
||
|
return src
|
||
|
|
||
|
def _gen_iter(self):
|
||
|
src = ' def __iter__(self):\n'
|
||
|
|
||
|
if self.all_entries:
|
||
|
for child in self.child:
|
||
|
src += (
|
||
|
' if self.%(child)s is not None:\n' +
|
||
|
' yield self.%(child)s\n') % (dict(child=child))
|
||
|
|
||
|
for seq_child in self.seq_child:
|
||
|
src += (
|
||
|
' for child in (self.%(child)s or []):\n'
|
||
|
' yield child\n') % (dict(child=seq_child))
|
||
|
|
||
|
if not (self.child or self.seq_child):
|
||
|
# Empty generator
|
||
|
src += (
|
||
|
' return\n' +
|
||
|
' yield\n')
|
||
|
else:
|
||
|
# Empty generator
|
||
|
src += (
|
||
|
' return\n' +
|
||
|
' yield\n')
|
||
|
|
||
|
return src
|
||
|
|
||
|
def _gen_attr_names(self):
|
||
|
src = " attr_names = (" + ''.join("%r, " % nm for nm in self.attr) + ')'
|
||
|
return src
|
||
|
|
||
|
|
||
|
_PROLOGUE_COMMENT = \
|
||
|
r'''#-----------------------------------------------------------------
|
||
|
# ** ATTENTION **
|
||
|
# This code was automatically generated from the file:
|
||
|
# $cfg_filename
|
||
|
#
|
||
|
# Do not modify it directly. Modify the configuration file and
|
||
|
# run the generator again.
|
||
|
# ** ** *** ** **
|
||
|
#
|
||
|
# pycparser: c_ast.py
|
||
|
#
|
||
|
# AST Node classes.
|
||
|
#
|
||
|
# Eli Bendersky [https://eli.thegreenplace.net/]
|
||
|
# License: BSD
|
||
|
#-----------------------------------------------------------------
|
||
|
|
||
|
'''
|
||
|
|
||
|
_PROLOGUE_CODE = r'''
|
||
|
import sys
|
||
|
|
||
|
def _repr(obj):
|
||
|
"""
|
||
|
Get the representation of an object, with dedicated pprint-like format for lists.
|
||
|
"""
|
||
|
if isinstance(obj, list):
|
||
|
return '[' + (',\n '.join((_repr(e).replace('\n', '\n ') for e in obj))) + '\n]'
|
||
|
else:
|
||
|
return repr(obj)
|
||
|
|
||
|
class Node(object):
|
||
|
__slots__ = ()
|
||
|
""" Abstract base class for AST nodes.
|
||
|
"""
|
||
|
def __repr__(self):
|
||
|
""" Generates a python representation of the current node
|
||
|
"""
|
||
|
result = self.__class__.__name__ + '('
|
||
|
|
||
|
indent = ''
|
||
|
separator = ''
|
||
|
for name in self.__slots__[:-2]:
|
||
|
result += separator
|
||
|
result += indent
|
||
|
result += name + '=' + (_repr(getattr(self, name)).replace('\n', '\n ' + (' ' * (len(name) + len(self.__class__.__name__)))))
|
||
|
|
||
|
separator = ','
|
||
|
indent = '\n ' + (' ' * len(self.__class__.__name__))
|
||
|
|
||
|
result += indent + ')'
|
||
|
|
||
|
return result
|
||
|
|
||
|
def children(self):
|
||
|
""" A sequence of all children that are Nodes
|
||
|
"""
|
||
|
pass
|
||
|
|
||
|
def show(self, buf=sys.stdout, offset=0, attrnames=False, nodenames=False, showcoord=False, _my_node_name=None):
|
||
|
""" Pretty print the Node and all its attributes and
|
||
|
children (recursively) to a buffer.
|
||
|
|
||
|
buf:
|
||
|
Open IO buffer into which the Node is printed.
|
||
|
|
||
|
offset:
|
||
|
Initial offset (amount of leading spaces)
|
||
|
|
||
|
attrnames:
|
||
|
True if you want to see the attribute names in
|
||
|
name=value pairs. False to only see the values.
|
||
|
|
||
|
nodenames:
|
||
|
True if you want to see the actual node names
|
||
|
within their parents.
|
||
|
|
||
|
showcoord:
|
||
|
Do you want the coordinates of each Node to be
|
||
|
displayed.
|
||
|
"""
|
||
|
lead = ' ' * offset
|
||
|
if nodenames and _my_node_name is not None:
|
||
|
buf.write(lead + self.__class__.__name__+ ' <' + _my_node_name + '>: ')
|
||
|
else:
|
||
|
buf.write(lead + self.__class__.__name__+ ': ')
|
||
|
|
||
|
if self.attr_names:
|
||
|
if attrnames:
|
||
|
nvlist = [(n, getattr(self,n)) for n in self.attr_names]
|
||
|
attrstr = ', '.join('%s=%s' % nv for nv in nvlist)
|
||
|
else:
|
||
|
vlist = [getattr(self, n) for n in self.attr_names]
|
||
|
attrstr = ', '.join('%s' % v for v in vlist)
|
||
|
buf.write(attrstr)
|
||
|
|
||
|
if showcoord:
|
||
|
buf.write(' (at %s)' % self.coord)
|
||
|
buf.write('\n')
|
||
|
|
||
|
for (child_name, child) in self.children():
|
||
|
child.show(
|
||
|
buf,
|
||
|
offset=offset + 2,
|
||
|
attrnames=attrnames,
|
||
|
nodenames=nodenames,
|
||
|
showcoord=showcoord,
|
||
|
_my_node_name=child_name)
|
||
|
|
||
|
|
||
|
class NodeVisitor(object):
|
||
|
""" A base NodeVisitor class for visiting c_ast nodes.
|
||
|
Subclass it and define your own visit_XXX methods, where
|
||
|
XXX is the class name you want to visit with these
|
||
|
methods.
|
||
|
|
||
|
For example:
|
||
|
|
||
|
class ConstantVisitor(NodeVisitor):
|
||
|
def __init__(self):
|
||
|
self.values = []
|
||
|
|
||
|
def visit_Constant(self, node):
|
||
|
self.values.append(node.value)
|
||
|
|
||
|
Creates a list of values of all the constant nodes
|
||
|
encountered below the given node. To use it:
|
||
|
|
||
|
cv = ConstantVisitor()
|
||
|
cv.visit(node)
|
||
|
|
||
|
Notes:
|
||
|
|
||
|
* generic_visit() will be called for AST nodes for which
|
||
|
no visit_XXX method was defined.
|
||
|
* The children of nodes for which a visit_XXX was
|
||
|
defined will not be visited - if you need this, call
|
||
|
generic_visit() on the node.
|
||
|
You can use:
|
||
|
NodeVisitor.generic_visit(self, node)
|
||
|
* Modeled after Python's own AST visiting facilities
|
||
|
(the ast module of Python 3.0)
|
||
|
"""
|
||
|
|
||
|
_method_cache = None
|
||
|
|
||
|
def visit(self, node):
|
||
|
""" Visit a node.
|
||
|
"""
|
||
|
|
||
|
if self._method_cache is None:
|
||
|
self._method_cache = {}
|
||
|
|
||
|
visitor = self._method_cache.get(node.__class__.__name__, None)
|
||
|
if visitor is None:
|
||
|
method = 'visit_' + node.__class__.__name__
|
||
|
visitor = getattr(self, method, self.generic_visit)
|
||
|
self._method_cache[node.__class__.__name__] = visitor
|
||
|
|
||
|
return visitor(node)
|
||
|
|
||
|
def generic_visit(self, node):
|
||
|
""" Called if no explicit visitor function exists for a
|
||
|
node. Implements preorder visiting of the node.
|
||
|
"""
|
||
|
for c in node:
|
||
|
self.visit(c)
|
||
|
|
||
|
'''
|