AlkantarClanX12
Current Path : /opt/hc_python/lib/python3.8/site-packages/mako/ |
Current File : //opt/hc_python/lib/python3.8/site-packages/mako/ast.py |
# mako/ast.py # Copyright 2006-2024 the Mako authors and contributors <see AUTHORS file> # # This module is part of Mako and is released under # the MIT License: http://www.opensource.org/licenses/mit-license.php """utilities for analyzing expressions and blocks of Python code, as well as generating Python from AST nodes""" import re from mako import exceptions from mako import pyparser class PythonCode: """represents information about a string containing Python code""" def __init__(self, code, **exception_kwargs): self.code = code # represents all identifiers which are assigned to at some point in # the code self.declared_identifiers = set() # represents all identifiers which are referenced before their # assignment, if any self.undeclared_identifiers = set() # note that an identifier can be in both the undeclared and declared # lists. # using AST to parse instead of using code.co_varnames, # code.co_names has several advantages: # - we can locate an identifier as "undeclared" even if # its declared later in the same block of code # - AST is less likely to break with version changes # (for example, the behavior of co_names changed a little bit # in python version 2.5) if isinstance(code, str): expr = pyparser.parse(code.lstrip(), "exec", **exception_kwargs) else: expr = code f = pyparser.FindIdentifiers(self, **exception_kwargs) f.visit(expr) class ArgumentList: """parses a fragment of code as a comma-separated list of expressions""" def __init__(self, code, **exception_kwargs): self.codeargs = [] self.args = [] self.declared_identifiers = set() self.undeclared_identifiers = set() if isinstance(code, str): if re.match(r"\S", code) and not re.match(r",\s*$", code): # if theres text and no trailing comma, insure its parsed # as a tuple by adding a trailing comma code += "," expr = pyparser.parse(code, "exec", **exception_kwargs) else: expr = code f = pyparser.FindTuple(self, PythonCode, **exception_kwargs) f.visit(expr) class PythonFragment(PythonCode): """extends PythonCode to provide identifier lookups in partial control statements e.g.:: for x in 5: elif y==9: except (MyException, e): """ def __init__(self, code, **exception_kwargs): m = re.match(r"^(\w+)(?:\s+(.*?))?:\s*(#|$)", code.strip(), re.S) if not m: raise exceptions.CompileException( "Fragment '%s' is not a partial control statement" % code, **exception_kwargs, ) if m.group(3): code = code[: m.start(3)] (keyword, expr) = m.group(1, 2) if keyword in ["for", "if", "while"]: code = code + "pass" elif keyword == "try": code = code + "pass\nexcept:pass" elif keyword in ["elif", "else"]: code = "if False:pass\n" + code + "pass" elif keyword == "except": code = "try:pass\n" + code + "pass" elif keyword == "with": code = code + "pass" else: raise exceptions.CompileException( "Unsupported control keyword: '%s'" % keyword, **exception_kwargs, ) super().__init__(code, **exception_kwargs) class FunctionDecl: """function declaration""" def __init__(self, code, allow_kwargs=True, **exception_kwargs): self.code = code expr = pyparser.parse(code, "exec", **exception_kwargs) f = pyparser.ParseFunc(self, **exception_kwargs) f.visit(expr) if not hasattr(self, "funcname"): raise exceptions.CompileException( "Code '%s' is not a function declaration" % code, **exception_kwargs, ) if not allow_kwargs and self.kwargs: raise exceptions.CompileException( "'**%s' keyword argument not allowed here" % self.kwargnames[-1], **exception_kwargs, ) def get_argument_expressions(self, as_call=False): """Return the argument declarations of this FunctionDecl as a printable list. By default the return value is appropriate for writing in a ``def``; set `as_call` to true to build arguments to be passed to the function instead (assuming locals with the same names as the arguments exist). """ namedecls = [] # Build in reverse order, since defaults and slurpy args come last argnames = self.argnames[::-1] kwargnames = self.kwargnames[::-1] defaults = self.defaults[::-1] kwdefaults = self.kwdefaults[::-1] # Named arguments if self.kwargs: namedecls.append("**" + kwargnames.pop(0)) for name in kwargnames: # Keyword-only arguments must always be used by name, so even if # this is a call, print out `foo=foo` if as_call: namedecls.append("%s=%s" % (name, name)) elif kwdefaults: default = kwdefaults.pop(0) if default is None: # The AST always gives kwargs a default, since you can do # `def foo(*, a=1, b, c=3)` namedecls.append(name) else: namedecls.append( "%s=%s" % (name, pyparser.ExpressionGenerator(default).value()) ) else: namedecls.append(name) # Positional arguments if self.varargs: namedecls.append("*" + argnames.pop(0)) for name in argnames: if as_call or not defaults: namedecls.append(name) else: default = defaults.pop(0) namedecls.append( "%s=%s" % (name, pyparser.ExpressionGenerator(default).value()) ) namedecls.reverse() return namedecls @property def allargnames(self): return tuple(self.argnames) + tuple(self.kwargnames) class FunctionArgs(FunctionDecl): """the argument portion of a function declaration""" def __init__(self, code, **kwargs): super().__init__("def ANON(%s):pass" % code, **kwargs)