Spaces:
Running
Running
File size: 10,704 Bytes
122d3ff |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 |
import typing as t
from . import nodes
from .visitor import NodeVisitor
VAR_LOAD_PARAMETER = "param"
VAR_LOAD_RESOLVE = "resolve"
VAR_LOAD_ALIAS = "alias"
VAR_LOAD_UNDEFINED = "undefined"
def find_symbols(
nodes: t.Iterable[nodes.Node], parent_symbols: t.Optional["Symbols"] = None
) -> "Symbols":
sym = Symbols(parent=parent_symbols)
visitor = FrameSymbolVisitor(sym)
for node in nodes:
visitor.visit(node)
return sym
def symbols_for_node(
node: nodes.Node, parent_symbols: t.Optional["Symbols"] = None
) -> "Symbols":
sym = Symbols(parent=parent_symbols)
sym.analyze_node(node)
return sym
class Symbols:
def __init__(
self, parent: t.Optional["Symbols"] = None, level: t.Optional[int] = None
) -> None:
if level is None:
if parent is None:
level = 0
else:
level = parent.level + 1
self.level: int = level
self.parent = parent
self.refs: t.Dict[str, str] = {}
self.loads: t.Dict[str, t.Any] = {}
self.stores: t.Set[str] = set()
def analyze_node(self, node: nodes.Node, **kwargs: t.Any) -> None:
visitor = RootVisitor(self)
visitor.visit(node, **kwargs)
def _define_ref(
self, name: str, load: t.Optional[t.Tuple[str, t.Optional[str]]] = None
) -> str:
ident = f"l_{self.level}_{name}"
self.refs[name] = ident
if load is not None:
self.loads[ident] = load
return ident
def find_load(self, target: str) -> t.Optional[t.Any]:
if target in self.loads:
return self.loads[target]
if self.parent is not None:
return self.parent.find_load(target)
return None
def find_ref(self, name: str) -> t.Optional[str]:
if name in self.refs:
return self.refs[name]
if self.parent is not None:
return self.parent.find_ref(name)
return None
def ref(self, name: str) -> str:
rv = self.find_ref(name)
if rv is None:
raise AssertionError(
"Tried to resolve a name to a reference that was"
f" unknown to the frame ({name!r})"
)
return rv
def copy(self) -> "Symbols":
rv = object.__new__(self.__class__)
rv.__dict__.update(self.__dict__)
rv.refs = self.refs.copy()
rv.loads = self.loads.copy()
rv.stores = self.stores.copy()
return rv
def store(self, name: str) -> None:
self.stores.add(name)
# If we have not see the name referenced yet, we need to figure
# out what to set it to.
if name not in self.refs:
# If there is a parent scope we check if the name has a
# reference there. If it does it means we might have to alias
# to a variable there.
if self.parent is not None:
outer_ref = self.parent.find_ref(name)
if outer_ref is not None:
self._define_ref(name, load=(VAR_LOAD_ALIAS, outer_ref))
return
# Otherwise we can just set it to undefined.
self._define_ref(name, load=(VAR_LOAD_UNDEFINED, None))
def declare_parameter(self, name: str) -> str:
self.stores.add(name)
return self._define_ref(name, load=(VAR_LOAD_PARAMETER, None))
def load(self, name: str) -> None:
if self.find_ref(name) is None:
self._define_ref(name, load=(VAR_LOAD_RESOLVE, name))
def branch_update(self, branch_symbols: t.Sequence["Symbols"]) -> None:
stores: t.Dict[str, int] = {}
for branch in branch_symbols:
for target in branch.stores:
if target in self.stores:
continue
stores[target] = stores.get(target, 0) + 1
for sym in branch_symbols:
self.refs.update(sym.refs)
self.loads.update(sym.loads)
self.stores.update(sym.stores)
for name, branch_count in stores.items():
if branch_count == len(branch_symbols):
continue
target = self.find_ref(name) # type: ignore
assert target is not None, "should not happen"
if self.parent is not None:
outer_target = self.parent.find_ref(name)
if outer_target is not None:
self.loads[target] = (VAR_LOAD_ALIAS, outer_target)
continue
self.loads[target] = (VAR_LOAD_RESOLVE, name)
def dump_stores(self) -> t.Dict[str, str]:
rv: t.Dict[str, str] = {}
node: t.Optional["Symbols"] = self
while node is not None:
for name in sorted(node.stores):
if name not in rv:
rv[name] = self.find_ref(name) # type: ignore
node = node.parent
return rv
def dump_param_targets(self) -> t.Set[str]:
rv = set()
node: t.Optional["Symbols"] = self
while node is not None:
for target, (instr, _) in self.loads.items():
if instr == VAR_LOAD_PARAMETER:
rv.add(target)
node = node.parent
return rv
class RootVisitor(NodeVisitor):
def __init__(self, symbols: "Symbols") -> None:
self.sym_visitor = FrameSymbolVisitor(symbols)
def _simple_visit(self, node: nodes.Node, **kwargs: t.Any) -> None:
for child in node.iter_child_nodes():
self.sym_visitor.visit(child)
visit_Template = _simple_visit
visit_Block = _simple_visit
visit_Macro = _simple_visit
visit_FilterBlock = _simple_visit
visit_Scope = _simple_visit
visit_If = _simple_visit
visit_ScopedEvalContextModifier = _simple_visit
def visit_AssignBlock(self, node: nodes.AssignBlock, **kwargs: t.Any) -> None:
for child in node.body:
self.sym_visitor.visit(child)
def visit_CallBlock(self, node: nodes.CallBlock, **kwargs: t.Any) -> None:
for child in node.iter_child_nodes(exclude=("call",)):
self.sym_visitor.visit(child)
def visit_OverlayScope(self, node: nodes.OverlayScope, **kwargs: t.Any) -> None:
for child in node.body:
self.sym_visitor.visit(child)
def visit_For(
self, node: nodes.For, for_branch: str = "body", **kwargs: t.Any
) -> None:
if for_branch == "body":
self.sym_visitor.visit(node.target, store_as_param=True)
branch = node.body
elif for_branch == "else":
branch = node.else_
elif for_branch == "test":
self.sym_visitor.visit(node.target, store_as_param=True)
if node.test is not None:
self.sym_visitor.visit(node.test)
return
else:
raise RuntimeError("Unknown for branch")
if branch:
for item in branch:
self.sym_visitor.visit(item)
def visit_With(self, node: nodes.With, **kwargs: t.Any) -> None:
for target in node.targets:
self.sym_visitor.visit(target)
for child in node.body:
self.sym_visitor.visit(child)
def generic_visit(self, node: nodes.Node, *args: t.Any, **kwargs: t.Any) -> None:
raise NotImplementedError(f"Cannot find symbols for {type(node).__name__!r}")
class FrameSymbolVisitor(NodeVisitor):
"""A visitor for `Frame.inspect`."""
def __init__(self, symbols: "Symbols") -> None:
self.symbols = symbols
def visit_Name(
self, node: nodes.Name, store_as_param: bool = False, **kwargs: t.Any
) -> None:
"""All assignments to names go through this function."""
if store_as_param or node.ctx == "param":
self.symbols.declare_parameter(node.name)
elif node.ctx == "store":
self.symbols.store(node.name)
elif node.ctx == "load":
self.symbols.load(node.name)
def visit_NSRef(self, node: nodes.NSRef, **kwargs: t.Any) -> None:
self.symbols.load(node.name)
def visit_If(self, node: nodes.If, **kwargs: t.Any) -> None:
self.visit(node.test, **kwargs)
original_symbols = self.symbols
def inner_visit(nodes: t.Iterable[nodes.Node]) -> "Symbols":
self.symbols = rv = original_symbols.copy()
for subnode in nodes:
self.visit(subnode, **kwargs)
self.symbols = original_symbols
return rv
body_symbols = inner_visit(node.body)
elif_symbols = inner_visit(node.elif_)
else_symbols = inner_visit(node.else_ or ())
self.symbols.branch_update([body_symbols, elif_symbols, else_symbols])
def visit_Macro(self, node: nodes.Macro, **kwargs: t.Any) -> None:
self.symbols.store(node.name)
def visit_Import(self, node: nodes.Import, **kwargs: t.Any) -> None:
self.generic_visit(node, **kwargs)
self.symbols.store(node.target)
def visit_FromImport(self, node: nodes.FromImport, **kwargs: t.Any) -> None:
self.generic_visit(node, **kwargs)
for name in node.names:
if isinstance(name, tuple):
self.symbols.store(name[1])
else:
self.symbols.store(name)
def visit_Assign(self, node: nodes.Assign, **kwargs: t.Any) -> None:
"""Visit assignments in the correct order."""
self.visit(node.node, **kwargs)
self.visit(node.target, **kwargs)
def visit_For(self, node: nodes.For, **kwargs: t.Any) -> None:
"""Visiting stops at for blocks. However the block sequence
is visited as part of the outer scope.
"""
self.visit(node.iter, **kwargs)
def visit_CallBlock(self, node: nodes.CallBlock, **kwargs: t.Any) -> None:
self.visit(node.call, **kwargs)
def visit_FilterBlock(self, node: nodes.FilterBlock, **kwargs: t.Any) -> None:
self.visit(node.filter, **kwargs)
def visit_With(self, node: nodes.With, **kwargs: t.Any) -> None:
for target in node.values:
self.visit(target)
def visit_AssignBlock(self, node: nodes.AssignBlock, **kwargs: t.Any) -> None:
"""Stop visiting at block assigns."""
self.visit(node.target, **kwargs)
def visit_Scope(self, node: nodes.Scope, **kwargs: t.Any) -> None:
"""Stop visiting at scopes."""
def visit_Block(self, node: nodes.Block, **kwargs: t.Any) -> None:
"""Stop visiting at blocks."""
def visit_OverlayScope(self, node: nodes.OverlayScope, **kwargs: t.Any) -> None:
"""Do not visit into overlay scopes."""
|