| 1 | """
|
| 2 | const_pass.py - AST pass that collects constants.
|
| 3 |
|
| 4 | Immutable string constants like 'StrFromC("foo")' are moved to the top level of
|
| 5 | the generated C++ program for efficiency.
|
| 6 | """
|
| 7 | import json
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| 8 |
|
| 9 | from typing import overload, Union, Optional, Dict, List
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| 10 |
|
| 11 | import mypy
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| 12 | from mypy.visitor import ExpressionVisitor, StatementVisitor
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| 13 | from mypy.nodes import (Expression, Statement, ExpressionStmt, StrExpr,
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| 14 | ComparisonExpr, NameExpr, MemberExpr)
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| 15 |
|
| 16 | from mypy.types import Type
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| 17 |
|
| 18 | from mycpp.crash import catch_errors
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| 19 | from mycpp import format_strings
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| 20 | from mycpp.util import log
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| 21 | from mycpp import util
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| 22 |
|
| 23 | T = None # TODO: Make it type check?
|
| 24 |
|
| 25 |
|
| 26 | class UnsupportedException(Exception):
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| 27 | pass
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| 28 |
|
| 29 |
|
| 30 | class Collect(ExpressionVisitor[T], StatementVisitor[None]):
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| 31 |
|
| 32 | def __init__(self, types: Dict[Expression, Type],
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| 33 | const_lookup: Dict[Expression, str], const_code: List[str]):
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| 34 |
|
| 35 | self.types = types
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| 36 | self.const_lookup = const_lookup
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| 37 | self.const_code = const_code
|
| 38 | self.unique_id = 0
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| 39 |
|
| 40 | self.indent = 0
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| 41 |
|
| 42 | def out(self, msg, *args):
|
| 43 | if args:
|
| 44 | msg = msg % args
|
| 45 | self.const_code.append(msg)
|
| 46 |
|
| 47 | #
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| 48 | # COPIED from IRBuilder
|
| 49 | #
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| 50 |
|
| 51 | @overload
|
| 52 | def accept(self, node: Expression) -> T:
|
| 53 | ...
|
| 54 |
|
| 55 | @overload
|
| 56 | def accept(self, node: Statement) -> None:
|
| 57 | ...
|
| 58 |
|
| 59 | def accept(self, node: Union[Statement, Expression]) -> Optional[T]:
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| 60 | with catch_errors(self.module_path, node.line):
|
| 61 | if isinstance(node, Expression):
|
| 62 | try:
|
| 63 | res = node.accept(self)
|
| 64 | #res = self.coerce(res, self.node_type(node), node.line)
|
| 65 |
|
| 66 | # If we hit an error during compilation, we want to
|
| 67 | # keep trying, so we can produce more error
|
| 68 | # messages. Generate a temp of the right type to keep
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| 69 | # from causing more downstream trouble.
|
| 70 | except UnsupportedException:
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| 71 | res = self.alloc_temp(self.node_type(node))
|
| 72 | return res
|
| 73 | else:
|
| 74 | try:
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| 75 | node.accept(self)
|
| 76 | except UnsupportedException:
|
| 77 | pass
|
| 78 | return None
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| 79 |
|
| 80 | def log(self, msg, *args):
|
| 81 | if 0: # quiet
|
| 82 | ind_str = self.indent * ' '
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| 83 | log(ind_str + msg, *args)
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| 84 |
|
| 85 | # Not in superclasses:
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| 86 |
|
| 87 | def visit_mypy_file(self, o: 'mypy.nodes.MypyFile') -> T:
|
| 88 | # Skip some stdlib stuff. A lot of it is brought in by 'import
|
| 89 | # typing'.
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| 90 | if o.fullname in ('__future__', 'sys', 'types', 'typing', 'abc',
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| 91 | '_ast', 'ast', '_weakrefset', 'collections',
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| 92 | 'cStringIO', 're', 'builtins'):
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| 93 |
|
| 94 | # These module are special; their contents are currently all
|
| 95 | # built-in primitives.
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| 96 | return
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| 97 |
|
| 98 | self.module_path = o.path
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| 99 |
|
| 100 | self.indent += 1
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| 101 | for node in o.defs:
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| 102 | # skip module docstring
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| 103 | if isinstance(node, ExpressionStmt) and isinstance(
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| 104 | node.expr, StrExpr):
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| 105 | continue
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| 106 | self.accept(node)
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| 107 | self.indent -= 1
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| 108 |
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| 109 | # LITERALS
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| 110 |
|
| 111 | def visit_int_expr(self, o: 'mypy.nodes.IntExpr') -> T:
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| 112 | self.log('IntExpr %d', o.value)
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| 113 |
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| 114 | def visit_str_expr(self, o: 'mypy.nodes.StrExpr') -> T:
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| 115 | id_ = 'str%d' % self.unique_id
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| 116 | self.unique_id += 1
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| 117 |
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| 118 | raw_string = format_strings.DecodeMyPyString(o.value)
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| 119 |
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| 120 | if util.SMALL_STR:
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| 121 | self.out('GLOBAL_STR2(%s, %s);', id_, json.dumps(raw_string))
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| 122 | else:
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| 123 | self.out('GLOBAL_STR(%s, %s);', id_, json.dumps(raw_string))
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| 124 |
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| 125 | self.const_lookup[o] = id_
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| 126 |
|
| 127 | def visit_bytes_expr(self, o: 'mypy.nodes.BytesExpr') -> T:
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| 128 | pass
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| 129 |
|
| 130 | def visit_unicode_expr(self, o: 'mypy.nodes.UnicodeExpr') -> T:
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| 131 | pass
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| 132 |
|
| 133 | def visit_float_expr(self, o: 'mypy.nodes.FloatExpr') -> T:
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| 134 | pass
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| 135 |
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| 136 | def visit_complex_expr(self, o: 'mypy.nodes.ComplexExpr') -> T:
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| 137 | pass
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| 138 |
|
| 139 | # Expression
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| 140 |
|
| 141 | def visit_ellipsis(self, o: 'mypy.nodes.EllipsisExpr') -> T:
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| 142 | pass
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| 143 |
|
| 144 | def visit_star_expr(self, o: 'mypy.nodes.StarExpr') -> T:
|
| 145 | pass
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| 146 |
|
| 147 | def visit_name_expr(self, o: 'mypy.nodes.NameExpr') -> T:
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| 148 | #self.log('NameExpr %s', o.name)
|
| 149 | pass
|
| 150 |
|
| 151 | def visit_member_expr(self, o: 'mypy.nodes.MemberExpr') -> T:
|
| 152 | if o.expr:
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| 153 | self.accept(o.expr)
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| 154 |
|
| 155 | def visit_yield_from_expr(self, o: 'mypy.nodes.YieldFromExpr') -> T:
|
| 156 | pass
|
| 157 |
|
| 158 | def visit_yield_expr(self, o: 'mypy.nodes.YieldExpr') -> T:
|
| 159 | pass
|
| 160 |
|
| 161 | def visit_call_expr(self, o: 'mypy.nodes.CallExpr') -> T:
|
| 162 | self.log('CallExpr')
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| 163 | self.accept(o.callee) # could be f() or obj.method()
|
| 164 | if o.callee.name == 'probe':
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| 165 | # don't generate constants for probe names
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| 166 | return
|
| 167 |
|
| 168 | self.indent += 1
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| 169 | for arg in o.args:
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| 170 | self.accept(arg)
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| 171 | # The type of each argument
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| 172 | #self.log(':: %s', self.types[arg])
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| 173 | self.indent -= 1
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| 174 | #self.log( 'args %s', o.args)
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| 175 |
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| 176 | #self.log(' arg_kinds %s', o.arg_kinds)
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| 177 | #self.log(' arg_names %s', o.arg_names)
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| 178 |
|
| 179 | def visit_op_expr(self, o: 'mypy.nodes.OpExpr') -> T:
|
| 180 | self.log('OpExpr')
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| 181 | self.indent += 1
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| 182 | self.accept(o.left)
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| 183 | self.accept(o.right)
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| 184 | self.indent -= 1
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| 185 |
|
| 186 | def visit_comparison_expr(self, o: 'mypy.nodes.ComparisonExpr') -> T:
|
| 187 | self.log('ComparisonExpr')
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| 188 | self.log(' operators %s', o.operators)
|
| 189 | self.indent += 1
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| 190 |
|
| 191 | for operand in o.operands:
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| 192 | self.indent += 1
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| 193 | self.accept(operand)
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| 194 | self.indent -= 1
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| 195 |
|
| 196 | self.indent -= 1
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| 197 |
|
| 198 | def visit_cast_expr(self, o: 'mypy.nodes.CastExpr') -> T:
|
| 199 | pass
|
| 200 |
|
| 201 | def visit_reveal_expr(self, o: 'mypy.nodes.RevealExpr') -> T:
|
| 202 | pass
|
| 203 |
|
| 204 | def visit_super_expr(self, o: 'mypy.nodes.SuperExpr') -> T:
|
| 205 | pass
|
| 206 |
|
| 207 | def visit_assignment_expr(self, o: 'mypy.nodes.AssignmentExpr') -> T:
|
| 208 | pass
|
| 209 |
|
| 210 | def visit_unary_expr(self, o: 'mypy.nodes.UnaryExpr') -> T:
|
| 211 | # e.g. a[-1] or 'not x'
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| 212 | self.accept(o.expr)
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| 213 |
|
| 214 | def visit_list_expr(self, o: 'mypy.nodes.ListExpr') -> T:
|
| 215 | # lists are MUTABLE, so we can't generate constants at the top level
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| 216 |
|
| 217 | # but we want to visit the string literals!
|
| 218 | for item in o.items:
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| 219 | self.accept(item)
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| 220 |
|
| 221 | def visit_dict_expr(self, o: 'mypy.nodes.DictExpr') -> T:
|
| 222 | for k, v in o.items:
|
| 223 | self.accept(k)
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| 224 | self.accept(v)
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| 225 |
|
| 226 | def visit_tuple_expr(self, o: 'mypy.nodes.TupleExpr') -> T:
|
| 227 | for item in o.items:
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| 228 | self.accept(item)
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| 229 |
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| 230 | def visit_set_expr(self, o: 'mypy.nodes.SetExpr') -> T:
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| 231 | pass
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| 232 |
|
| 233 | def visit_index_expr(self, o: 'mypy.nodes.IndexExpr') -> T:
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| 234 | self.accept(o.base)
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| 235 | self.accept(o.index)
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| 236 |
|
| 237 | def visit_type_application(self, o: 'mypy.nodes.TypeApplication') -> T:
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| 238 | pass
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| 239 |
|
| 240 | def visit_lambda_expr(self, o: 'mypy.nodes.LambdaExpr') -> T:
|
| 241 | pass
|
| 242 |
|
| 243 | def visit_list_comprehension(self, o: 'mypy.nodes.ListComprehension') -> T:
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| 244 | gen = o.generator # GeneratorExpr
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| 245 | left_expr = gen.left_expr
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| 246 | index_expr = gen.indices[0]
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| 247 | seq = gen.sequences[0]
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| 248 | cond = gen.condlists[0]
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| 249 |
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| 250 | # We might use all of these, so collect constants.
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| 251 | self.accept(left_expr)
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| 252 | self.accept(index_expr)
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| 253 | self.accept(seq)
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| 254 | for c in cond:
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| 255 | self.accept(c)
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| 256 |
|
| 257 | def visit_set_comprehension(self, o: 'mypy.nodes.SetComprehension') -> T:
|
| 258 | pass
|
| 259 |
|
| 260 | def visit_dictionary_comprehension(
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| 261 | self, o: 'mypy.nodes.DictionaryComprehension') -> T:
|
| 262 | pass
|
| 263 |
|
| 264 | def visit_generator_expr(self, o: 'mypy.nodes.GeneratorExpr') -> T:
|
| 265 | pass
|
| 266 |
|
| 267 | def visit_slice_expr(self, o: 'mypy.nodes.SliceExpr') -> T:
|
| 268 | if o.begin_index:
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| 269 | self.accept(o.begin_index)
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| 270 |
|
| 271 | if o.end_index:
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| 272 | self.accept(o.end_index)
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| 273 |
|
| 274 | if o.stride:
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| 275 | self.accept(o.stride)
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| 276 |
|
| 277 | def visit_conditional_expr(self, o: 'mypy.nodes.ConditionalExpr') -> T:
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| 278 | self.accept(o.cond)
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| 279 | self.accept(o.if_expr)
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| 280 | self.accept(o.else_expr)
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| 281 |
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| 282 | def visit_backquote_expr(self, o: 'mypy.nodes.BackquoteExpr') -> T:
|
| 283 | pass
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| 284 |
|
| 285 | def visit_type_var_expr(self, o: 'mypy.nodes.TypeVarExpr') -> T:
|
| 286 | pass
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| 287 |
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| 288 | def visit_type_alias_expr(self, o: 'mypy.nodes.TypeAliasExpr') -> T:
|
| 289 | pass
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| 290 |
|
| 291 | def visit_namedtuple_expr(self, o: 'mypy.nodes.NamedTupleExpr') -> T:
|
| 292 | pass
|
| 293 |
|
| 294 | def visit_enum_call_expr(self, o: 'mypy.nodes.EnumCallExpr') -> T:
|
| 295 | pass
|
| 296 |
|
| 297 | def visit_typeddict_expr(self, o: 'mypy.nodes.TypedDictExpr') -> T:
|
| 298 | pass
|
| 299 |
|
| 300 | def visit_newtype_expr(self, o: 'mypy.nodes.NewTypeExpr') -> T:
|
| 301 | pass
|
| 302 |
|
| 303 | def visit__promote_expr(self, o: 'mypy.nodes.PromoteExpr') -> T:
|
| 304 | pass
|
| 305 |
|
| 306 | def visit_await_expr(self, o: 'mypy.nodes.AwaitExpr') -> T:
|
| 307 | pass
|
| 308 |
|
| 309 | def visit_temp_node(self, o: 'mypy.nodes.TempNode') -> T:
|
| 310 | pass
|
| 311 |
|
| 312 | def visit_assignment_stmt(self, o: 'mypy.nodes.AssignmentStmt') -> T:
|
| 313 | # How does this get reached??
|
| 314 |
|
| 315 | # Ah wtf, why is there no type on here!
|
| 316 | # I thought we did parse_and_typecheck already?
|
| 317 |
|
| 318 | if 1:
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| 319 | self.log('AssignmentStmt')
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| 320 | #self.log(' type %s', o.type)
|
| 321 | #self.log(' unanalyzed_type %s', o.unanalyzed_type)
|
| 322 |
|
| 323 | # NICE! Got the lvalue
|
| 324 | for lval in o.lvalues:
|
| 325 | try:
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| 326 | self.log(' lval %s :: %s', lval, self.types[lval])
|
| 327 | except KeyError: # TODO: handle this
|
| 328 | pass
|
| 329 | self.accept(lval)
|
| 330 |
|
| 331 | try:
|
| 332 | r = self.types[o.rvalue]
|
| 333 | except KeyError:
|
| 334 | # This seems to only happen for Ellipsis, I guess in the abc module
|
| 335 | #log(' NO TYPE FOR RVALUE: %s', o.rvalue)
|
| 336 | pass
|
| 337 | else:
|
| 338 | #self.log(' %s :: %s', o.rvalue, r)
|
| 339 | self.indent += 1
|
| 340 | #self.log(' rvalue :: %s', r)
|
| 341 | self.accept(o.rvalue)
|
| 342 | self.indent -= 1
|
| 343 | #self.log(' o.rvalue %s', o.rvalue)
|
| 344 |
|
| 345 | def visit_for_stmt(self, o: 'mypy.nodes.ForStmt') -> T:
|
| 346 | self.log('ForStmt')
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| 347 | #self.log(' index_type %s', o.index_type)
|
| 348 | #self.log(' inferred_item_type %s', o.inferred_item_type)
|
| 349 | #self.log(' inferred_iterator_type %s', o.inferred_iterator_type)
|
| 350 | self.accept(o.index) # index var expression
|
| 351 | self.accept(o.expr) # the thing being iterated over
|
| 352 | self.accept(o.body)
|
| 353 | if o.else_body:
|
| 354 | raise AssertionError("can't translate for-else")
|
| 355 |
|
| 356 | def visit_with_stmt(self, o: 'mypy.nodes.WithStmt') -> T:
|
| 357 | assert len(o.expr) == 1, o.expr
|
| 358 | self.accept(o.expr[0])
|
| 359 | self.accept(o.body)
|
| 360 |
|
| 361 | def visit_del_stmt(self, o: 'mypy.nodes.DelStmt') -> T:
|
| 362 | self.accept(o.expr)
|
| 363 |
|
| 364 | def visit_func_def(self, o: 'mypy.nodes.FuncDef') -> T:
|
| 365 | # got the type here, nice!
|
| 366 | typ = o.type
|
| 367 | self.log('FuncDef %s :: %s', o.name, typ)
|
| 368 | #self.log('%s', type(typ))
|
| 369 |
|
| 370 | for t, name in zip(typ.arg_types, typ.arg_names):
|
| 371 | self.log(' arg %s %s', t, name)
|
| 372 | self.log(' ret %s', o.type.ret_type)
|
| 373 |
|
| 374 | self.indent += 1
|
| 375 | for arg in o.arguments:
|
| 376 | # e.g. foo=''
|
| 377 | if arg.initializer:
|
| 378 | self.accept(arg.initializer)
|
| 379 |
|
| 380 | # We can't use __str__ on these Argument objects? That seems like an
|
| 381 | # oversight
|
| 382 | #self.log('%r', arg)
|
| 383 |
|
| 384 | self.log('Argument %s', arg.variable)
|
| 385 | self.log(' type_annotation %s', arg.type_annotation)
|
| 386 | # I think these are for default values
|
| 387 | self.log(' initializer %s', arg.initializer)
|
| 388 | self.log(' kind %s', arg.kind)
|
| 389 |
|
| 390 | self.accept(o.body)
|
| 391 | self.indent -= 1
|
| 392 |
|
| 393 | def visit_overloaded_func_def(self,
|
| 394 | o: 'mypy.nodes.OverloadedFuncDef') -> T:
|
| 395 | pass
|
| 396 |
|
| 397 | def visit_class_def(self, o: 'mypy.nodes.ClassDef') -> T:
|
| 398 | self.log('const_pass ClassDef %s', o.name)
|
| 399 | for b in o.base_type_exprs:
|
| 400 | self.log(' base_type_expr %s', b)
|
| 401 | self.indent += 1
|
| 402 | self.accept(o.defs)
|
| 403 | self.indent -= 1
|
| 404 |
|
| 405 | def visit_global_decl(self, o: 'mypy.nodes.GlobalDecl') -> T:
|
| 406 | pass
|
| 407 |
|
| 408 | def visit_nonlocal_decl(self, o: 'mypy.nodes.NonlocalDecl') -> T:
|
| 409 | pass
|
| 410 |
|
| 411 | def visit_decorator(self, o: 'mypy.nodes.Decorator') -> T:
|
| 412 | pass
|
| 413 |
|
| 414 | def visit_var(self, o: 'mypy.nodes.Var') -> T:
|
| 415 | pass
|
| 416 |
|
| 417 | # Module structure
|
| 418 |
|
| 419 | def visit_import(self, o: 'mypy.nodes.Import') -> T:
|
| 420 | pass
|
| 421 |
|
| 422 | def visit_import_from(self, o: 'mypy.nodes.ImportFrom') -> T:
|
| 423 | pass
|
| 424 |
|
| 425 | def visit_import_all(self, o: 'mypy.nodes.ImportAll') -> T:
|
| 426 | pass
|
| 427 |
|
| 428 | # Statements
|
| 429 |
|
| 430 | def visit_block(self, block: 'mypy.nodes.Block') -> T:
|
| 431 | self.log('Block')
|
| 432 | self.indent += 1
|
| 433 | for stmt in block.body:
|
| 434 | # Ignore things that look like docstrings
|
| 435 | if isinstance(stmt, ExpressionStmt) and isinstance(
|
| 436 | stmt.expr, StrExpr):
|
| 437 | continue
|
| 438 | #log('-- %d', self.indent)
|
| 439 | self.accept(stmt)
|
| 440 | self.indent -= 1
|
| 441 |
|
| 442 | def visit_expression_stmt(self, o: 'mypy.nodes.ExpressionStmt') -> T:
|
| 443 | self.log('ExpressionStmt')
|
| 444 | self.indent += 1
|
| 445 | self.accept(o.expr)
|
| 446 | self.indent -= 1
|
| 447 |
|
| 448 | def visit_operator_assignment_stmt(
|
| 449 | self, o: 'mypy.nodes.OperatorAssignmentStmt') -> T:
|
| 450 | self.log('OperatorAssignmentStmt')
|
| 451 |
|
| 452 | def visit_while_stmt(self, o: 'mypy.nodes.WhileStmt') -> T:
|
| 453 | self.log('WhileStmt')
|
| 454 | self.accept(o.expr)
|
| 455 | self.accept(o.body)
|
| 456 |
|
| 457 | def visit_return_stmt(self, o: 'mypy.nodes.ReturnStmt') -> T:
|
| 458 | self.log('ReturnStmt')
|
| 459 | if o.expr:
|
| 460 | self.accept(o.expr)
|
| 461 |
|
| 462 | def visit_assert_stmt(self, o: 'mypy.nodes.AssertStmt') -> T:
|
| 463 | pass
|
| 464 |
|
| 465 | def visit_if_stmt(self, o: 'mypy.nodes.IfStmt') -> T:
|
| 466 | # Copied from cppgen_pass.py
|
| 467 | # Not sure why this wouldn't be true
|
| 468 | assert len(o.expr) == 1, o.expr
|
| 469 |
|
| 470 | # Omit anything that looks like if __name__ == ...
|
| 471 | cond = o.expr[0]
|
| 472 | if (isinstance(cond, ComparisonExpr) and
|
| 473 | isinstance(cond.operands[0], NameExpr) and
|
| 474 | cond.operands[0].name == '__name__'):
|
| 475 | return
|
| 476 |
|
| 477 | # Omit if TYPE_CHECKING blocks. They contain type expressions that
|
| 478 | # don't type check!
|
| 479 | if isinstance(cond, NameExpr) and cond.name == 'TYPE_CHECKING':
|
| 480 | return
|
| 481 | # mylib.CPP
|
| 482 | if isinstance(cond, MemberExpr) and cond.name == 'CPP':
|
| 483 | # just take the if block
|
| 484 | for node in o.body:
|
| 485 | self.accept(node)
|
| 486 | return
|
| 487 | # mylib.PYTHON
|
| 488 | if isinstance(cond, MemberExpr) and cond.name == 'PYTHON':
|
| 489 | if o.else_body:
|
| 490 | self.accept(o.else_body)
|
| 491 | return
|
| 492 |
|
| 493 | self.log('IfStmt')
|
| 494 | self.indent += 1
|
| 495 | for e in o.expr:
|
| 496 | self.accept(e)
|
| 497 |
|
| 498 | for node in o.body:
|
| 499 | self.accept(node)
|
| 500 |
|
| 501 | if o.else_body:
|
| 502 | self.accept(o.else_body)
|
| 503 | self.indent -= 1
|
| 504 |
|
| 505 | def visit_break_stmt(self, o: 'mypy.nodes.BreakStmt') -> T:
|
| 506 | pass
|
| 507 |
|
| 508 | def visit_continue_stmt(self, o: 'mypy.nodes.ContinueStmt') -> T:
|
| 509 | pass
|
| 510 |
|
| 511 | def visit_pass_stmt(self, o: 'mypy.nodes.PassStmt') -> T:
|
| 512 | pass
|
| 513 |
|
| 514 | def visit_raise_stmt(self, o: 'mypy.nodes.RaiseStmt') -> T:
|
| 515 | if o.expr:
|
| 516 | self.accept(o.expr)
|
| 517 |
|
| 518 | def visit_try_stmt(self, o: 'mypy.nodes.TryStmt') -> T:
|
| 519 | self.accept(o.body)
|
| 520 | for t, v, handler in zip(o.types, o.vars, o.handlers):
|
| 521 | self.accept(handler)
|
| 522 |
|
| 523 | #if o.else_body:
|
| 524 | # raise AssertionError('try/else not supported')
|
| 525 | #if o.finally_body:
|
| 526 | # raise AssertionError('try/finally not supported')
|
| 527 |
|
| 528 | def visit_print_stmt(self, o: 'mypy.nodes.PrintStmt') -> T:
|
| 529 | pass
|
| 530 |
|
| 531 | def visit_exec_stmt(self, o: 'mypy.nodes.ExecStmt') -> T:
|
| 532 | pass
|