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

1# mako/pyparser.py 

2# Copyright 2006-2023 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 

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

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

70 # is undeclared) 

71 

72 self.visit(node.value) 

73 in_a = self.in_assign_targets 

74 self.in_assign_targets = True 

75 for n in node.targets: 

76 self.visit(n) 

77 self.in_assign_targets = in_a 

78 

79 def visit_ExceptHandler(self, node): 

80 if node.name is not None: 

81 self._add_declared(node.name) 

82 if node.type is not None: 

83 self.visit(node.type) 

84 for statement in node.body: 

85 self.visit(statement) 

86 

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

88 self._visit_function(node, True) 

89 

90 def visit_FunctionDef(self, node): 

91 self._add_declared(node.name) 

92 self._visit_function(node, False) 

93 

94 def _expand_tuples(self, args): 

95 for arg in args: 

96 if isinstance(arg, _ast.Tuple): 

97 yield from arg.elts 

98 else: 

99 yield arg 

100 

101 def _visit_function(self, node, islambda): 

102 

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

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

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

106 # argument names in each function header so they arent 

107 # counted as "undeclared" 

108 

109 inf = self.in_function 

110 self.in_function = True 

111 

112 local_ident_stack = self.local_ident_stack 

113 self.local_ident_stack = local_ident_stack.union( 

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

115 ) 

116 if islambda: 

117 self.visit(node.body) 

118 else: 

119 for n in node.body: 

120 self.visit(n) 

121 self.in_function = inf 

122 self.local_ident_stack = local_ident_stack 

123 

124 def visit_For(self, node): 

125 

126 # flip around visit 

127 

128 self.visit(node.iter) 

129 self.visit(node.target) 

130 for statement in node.body: 

131 self.visit(statement) 

132 for statement in node.orelse: 

133 self.visit(statement) 

134 

135 def visit_Name(self, node): 

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

137 # this is eqiuvalent to visit_AssName in 

138 # compiler 

139 self._add_declared(node.id) 

140 elif ( 

141 node.id not in reserved 

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

143 and node.id not in self.local_ident_stack 

144 ): 

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

146 

147 def visit_Import(self, node): 

148 for name in node.names: 

149 if name.asname is not None: 

150 self._add_declared(name.asname) 

151 else: 

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

153 

154 def visit_ImportFrom(self, node): 

155 for name in node.names: 

156 if name.asname is not None: 

157 self._add_declared(name.asname) 

158 elif name.name == "*": 

159 raise exceptions.CompileException( 

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

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

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

163 "...' instead.", 

164 **self.exception_kwargs, 

165 ) 

166 else: 

167 self._add_declared(name.name) 

168 

169 

170class FindTuple(_ast_util.NodeVisitor): 

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

172 self.listener = listener 

173 self.exception_kwargs = exception_kwargs 

174 self.code_factory = code_factory 

175 

176 def visit_Tuple(self, node): 

177 for n in node.elts: 

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

179 self.listener.codeargs.append(p) 

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

181 ldi = self.listener.declared_identifiers 

182 self.listener.declared_identifiers = ldi.union( 

183 p.declared_identifiers 

184 ) 

185 lui = self.listener.undeclared_identifiers 

186 self.listener.undeclared_identifiers = lui.union( 

187 p.undeclared_identifiers 

188 ) 

189 

190 

191class ParseFunc(_ast_util.NodeVisitor): 

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

193 self.listener = listener 

194 self.exception_kwargs = exception_kwargs 

195 

196 def visit_FunctionDef(self, node): 

197 self.listener.funcname = node.name 

198 

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

200 if node.args.vararg: 

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

202 

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

204 if node.args.kwarg: 

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

206 self.listener.argnames = argnames 

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

208 self.listener.kwargnames = kwargnames 

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

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

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

212 

213 

214class ExpressionGenerator: 

215 def __init__(self, astnode): 

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

217 self.generator.visit(astnode) 

218 

219 def value(self): 

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