Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/mako/pyparser.py: 82%

1# mako/pyparser.py 

2# Copyright 2006-2024 the Mako authors and contributors <see AUTHORS file> 

3# 

4# This module is part of Mako and is released under 

5# the MIT License: http://www.opensource.org/licenses/mit-license.php 

6 

7"""Handles parsing of Python code. 

8 

9Parsing to AST is done via _ast on Python > 2.5, otherwise the compiler 

10module is used. 

11""" 

12 

13import operator 

14 

15import _ast 

16 

17from mako import _ast_util 

18from mako import compat 

19from mako import exceptions 

20from mako import util 

21 

22# words that cannot be assigned to (notably 

23# smaller than the total keys in __builtins__) 

24reserved = {"True", "False", "None", "print"} 

25 

26# the "id" attribute on a function node 

27arg_id = operator.attrgetter("arg") 

28 

29util.restore__ast(_ast) 

30 

31 

32def parse(code, mode="exec", **exception_kwargs): 

33 """Parse an expression into AST""" 

34 

35 try: 

36 return _ast_util.parse(code, "<unknown>", mode) 

37 except Exception as e: 

38 raise exceptions.SyntaxException( 

39 "(%s) %s (%r)" 

40 % ( 

41 compat.exception_as().__class__.__name__, 

42 compat.exception_as(), 

43 code[0:50], 

44 ), 

45 **exception_kwargs, 

46 ) from e 

47 

48 

49class FindIdentifiers(_ast_util.NodeVisitor): 

50 def __init__(self, listener, **exception_kwargs): 

51 self.in_function = False 

52 self.in_assign_targets = False 

53 self.local_ident_stack = set() 

54 self.listener = listener 

55 self.exception_kwargs = exception_kwargs 

56 

57 def _add_declared(self, name): 

58 if not self.in_function: 

59 self.listener.declared_identifiers.add(name) 

60 else: 

61 self.local_ident_stack.add(name) 

62 

63 def visit_ClassDef(self, node): 

64 self._add_declared(node.name) 

65 

66 def visit_Assign(self, node): 

67 # flip around the visiting of Assign so the expression gets 

68 # evaluated first, in the case of a clause like "x=x+5" (x 

69 # is undeclared) 

70 

71 self.visit(node.value) 

72 in_a = self.in_assign_targets 

73 self.in_assign_targets = True 

74 for n in node.targets: 

75 self.visit(n) 

76 self.in_assign_targets = in_a 

77 

78 def visit_ExceptHandler(self, node): 

79 if node.name is not None: 

80 self._add_declared(node.name) 

81 if node.type is not None: 

82 self.visit(node.type) 

83 for statement in node.body: 

84 self.visit(statement) 

85 

86 def visit_Lambda(self, node, *args): 

87 self._visit_function(node, True) 

88 

89 def visit_FunctionDef(self, node): 

90 self._add_declared(node.name) 

91 self._visit_function(node, False) 

92 

93 def _expand_tuples(self, args): 

94 for arg in args: 

95 if isinstance(arg, _ast.Tuple): 

96 yield from arg.elts 

97 else: 

98 yield arg 

99 

100 def _visit_function(self, node, islambda): 

101 # push function state onto stack. dont log any more 

102 # identifiers as "declared" until outside of the function, 

103 # but keep logging identifiers as "undeclared". track 

104 # argument names in each function header so they arent 

105 # counted as "undeclared" 

106 

107 inf = self.in_function 

108 self.in_function = True 

109 

110 local_ident_stack = self.local_ident_stack 

111 self.local_ident_stack = local_ident_stack.union( 

112 [arg_id(arg) for arg in self._expand_tuples(node.args.args)] 

113 ) 

114 if islambda: 

115 self.visit(node.body) 

116 else: 

117 for n in node.body: 

118 self.visit(n) 

119 self.in_function = inf 

120 self.local_ident_stack = local_ident_stack 

121 

122 def visit_For(self, node): 

123 # flip around visit 

124 

125 self.visit(node.iter) 

126 self.visit(node.target) 

127 for statement in node.body: 

128 self.visit(statement) 

129 for statement in node.orelse: 

130 self.visit(statement) 

131 

132 def visit_Name(self, node): 

133 if isinstance(node.ctx, _ast.Store): 

134 # this is eqiuvalent to visit_AssName in 

135 # compiler 

136 self._add_declared(node.id) 

137 elif ( 

138 node.id not in reserved 

139 and node.id not in self.listener.declared_identifiers 

140 and node.id not in self.local_ident_stack 

141 ): 

142 self.listener.undeclared_identifiers.add(node.id) 

143 

144 def visit_Import(self, node): 

145 for name in node.names: 

146 if name.asname is not None: 

147 self._add_declared(name.asname) 

148 else: 

149 self._add_declared(name.name.split(".")[0]) 

150 

151 def visit_ImportFrom(self, node): 

152 for name in node.names: 

153 if name.asname is not None: 

154 self._add_declared(name.asname) 

155 elif name.name == "*": 

156 raise exceptions.CompileException( 

157 "'import *' is not supported, since all identifier " 

158 "names must be explicitly declared. Please use the " 

159 "form 'from <modulename> import <name1>, <name2>, " 

160 "...' instead.", 

161 **self.exception_kwargs, 

162 ) 

163 else: 

164 self._add_declared(name.name) 

165 

166 

167class FindTuple(_ast_util.NodeVisitor): 

168 def __init__(self, listener, code_factory, **exception_kwargs): 

169 self.listener = listener 

170 self.exception_kwargs = exception_kwargs 

171 self.code_factory = code_factory 

172 

173 def visit_Tuple(self, node): 

174 for n in node.elts: 

175 p = self.code_factory(n, **self.exception_kwargs) 

176 self.listener.codeargs.append(p) 

177 self.listener.args.append(ExpressionGenerator(n).value()) 

178 ldi = self.listener.declared_identifiers 

179 self.listener.declared_identifiers = ldi.union( 

180 p.declared_identifiers 

181 ) 

182 lui = self.listener.undeclared_identifiers 

183 self.listener.undeclared_identifiers = lui.union( 

184 p.undeclared_identifiers 

185 ) 

186 

187 

188class ParseFunc(_ast_util.NodeVisitor): 

189 def __init__(self, listener, **exception_kwargs): 

190 self.listener = listener 

191 self.exception_kwargs = exception_kwargs 

192 

193 def visit_FunctionDef(self, node): 

194 self.listener.funcname = node.name 

195 

196 argnames = [arg_id(arg) for arg in node.args.args] 

197 if node.args.vararg: 

198 argnames.append(node.args.vararg.arg) 

199 

200 kwargnames = [arg_id(arg) for arg in node.args.kwonlyargs] 

201 if node.args.kwarg: 

202 kwargnames.append(node.args.kwarg.arg) 

203 self.listener.argnames = argnames 

204 self.listener.defaults = node.args.defaults # ast 

205 self.listener.kwargnames = kwargnames 

206 self.listener.kwdefaults = node.args.kw_defaults 

207 self.listener.varargs = node.args.vararg 

208 self.listener.kwargs = node.args.kwarg 

209 

210 

211class ExpressionGenerator: 

212 def __init__(self, astnode): 

213 self.generator = _ast_util.SourceGenerator(" " * 4) 

214 self.generator.visit(astnode) 

215 

216 def value(self): 

217 return "".join(self.generator.result)