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author | nkozlovskiy <nmk@ydb.tech> | 2023-09-29 12:24:06 +0300 |
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committer | nkozlovskiy <nmk@ydb.tech> | 2023-09-29 12:41:34 +0300 |
commit | e0e3e1717e3d33762ce61950504f9637a6e669ed (patch) | |
tree | bca3ff6939b10ed60c3d5c12439963a1146b9711 /contrib/tools/python3/src/Lib/symtable.py | |
parent | 38f2c5852db84c7b4d83adfcb009eb61541d1ccd (diff) | |
download | ydb-e0e3e1717e3d33762ce61950504f9637a6e669ed.tar.gz |
add ydb deps
Diffstat (limited to 'contrib/tools/python3/src/Lib/symtable.py')
-rw-r--r-- | contrib/tools/python3/src/Lib/symtable.py | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/contrib/tools/python3/src/Lib/symtable.py b/contrib/tools/python3/src/Lib/symtable.py new file mode 100644 index 0000000000..5dd71ffc6b --- /dev/null +++ b/contrib/tools/python3/src/Lib/symtable.py @@ -0,0 +1,326 @@ +"""Interface to the compiler's internal symbol tables""" + +import _symtable +from _symtable import (USE, DEF_GLOBAL, DEF_NONLOCAL, DEF_LOCAL, DEF_PARAM, + DEF_IMPORT, DEF_BOUND, DEF_ANNOT, SCOPE_OFF, SCOPE_MASK, FREE, + LOCAL, GLOBAL_IMPLICIT, GLOBAL_EXPLICIT, CELL) + +import weakref + +__all__ = ["symtable", "SymbolTable", "Class", "Function", "Symbol"] + +def symtable(code, filename, compile_type): + """ Return the toplevel *SymbolTable* for the source code. + + *filename* is the name of the file with the code + and *compile_type* is the *compile()* mode argument. + """ + top = _symtable.symtable(code, filename, compile_type) + return _newSymbolTable(top, filename) + +class SymbolTableFactory: + def __init__(self): + self.__memo = weakref.WeakValueDictionary() + + def new(self, table, filename): + if table.type == _symtable.TYPE_FUNCTION: + return Function(table, filename) + if table.type == _symtable.TYPE_CLASS: + return Class(table, filename) + return SymbolTable(table, filename) + + def __call__(self, table, filename): + key = table, filename + obj = self.__memo.get(key, None) + if obj is None: + obj = self.__memo[key] = self.new(table, filename) + return obj + +_newSymbolTable = SymbolTableFactory() + + +class SymbolTable: + + def __init__(self, raw_table, filename): + self._table = raw_table + self._filename = filename + self._symbols = {} + + def __repr__(self): + if self.__class__ == SymbolTable: + kind = "" + else: + kind = "%s " % self.__class__.__name__ + + if self._table.name == "top": + return "<{0}SymbolTable for module {1}>".format(kind, self._filename) + else: + return "<{0}SymbolTable for {1} in {2}>".format(kind, + self._table.name, + self._filename) + + def get_type(self): + """Return the type of the symbol table. + + The values returned are 'class', 'module' and + 'function'. + """ + if self._table.type == _symtable.TYPE_MODULE: + return "module" + if self._table.type == _symtable.TYPE_FUNCTION: + return "function" + if self._table.type == _symtable.TYPE_CLASS: + return "class" + assert self._table.type in (1, 2, 3), \ + "unexpected type: {0}".format(self._table.type) + + def get_id(self): + """Return an identifier for the table. + """ + return self._table.id + + def get_name(self): + """Return the table's name. + + This corresponds to the name of the class, function + or 'top' if the table is for a class, function or + global respectively. + """ + return self._table.name + + def get_lineno(self): + """Return the number of the first line in the + block for the table. + """ + return self._table.lineno + + def is_optimized(self): + """Return *True* if the locals in the table + are optimizable. + """ + return bool(self._table.type == _symtable.TYPE_FUNCTION) + + def is_nested(self): + """Return *True* if the block is a nested class + or function.""" + return bool(self._table.nested) + + def has_children(self): + """Return *True* if the block has nested namespaces. + """ + return bool(self._table.children) + + def get_identifiers(self): + """Return a view object containing the names of symbols in the table. + """ + return self._table.symbols.keys() + + def lookup(self, name): + """Lookup a *name* in the table. + + Returns a *Symbol* instance. + """ + sym = self._symbols.get(name) + if sym is None: + flags = self._table.symbols[name] + namespaces = self.__check_children(name) + module_scope = (self._table.name == "top") + sym = self._symbols[name] = Symbol(name, flags, namespaces, + module_scope=module_scope) + return sym + + def get_symbols(self): + """Return a list of *Symbol* instances for + names in the table. + """ + return [self.lookup(ident) for ident in self.get_identifiers()] + + def __check_children(self, name): + return [_newSymbolTable(st, self._filename) + for st in self._table.children + if st.name == name] + + def get_children(self): + """Return a list of the nested symbol tables. + """ + return [_newSymbolTable(st, self._filename) + for st in self._table.children] + + +class Function(SymbolTable): + + # Default values for instance variables + __params = None + __locals = None + __frees = None + __globals = None + __nonlocals = None + + def __idents_matching(self, test_func): + return tuple(ident for ident in self.get_identifiers() + if test_func(self._table.symbols[ident])) + + def get_parameters(self): + """Return a tuple of parameters to the function. + """ + if self.__params is None: + self.__params = self.__idents_matching(lambda x:x & DEF_PARAM) + return self.__params + + def get_locals(self): + """Return a tuple of locals in the function. + """ + if self.__locals is None: + locs = (LOCAL, CELL) + test = lambda x: ((x >> SCOPE_OFF) & SCOPE_MASK) in locs + self.__locals = self.__idents_matching(test) + return self.__locals + + def get_globals(self): + """Return a tuple of globals in the function. + """ + if self.__globals is None: + glob = (GLOBAL_IMPLICIT, GLOBAL_EXPLICIT) + test = lambda x:((x >> SCOPE_OFF) & SCOPE_MASK) in glob + self.__globals = self.__idents_matching(test) + return self.__globals + + def get_nonlocals(self): + """Return a tuple of nonlocals in the function. + """ + if self.__nonlocals is None: + self.__nonlocals = self.__idents_matching(lambda x:x & DEF_NONLOCAL) + return self.__nonlocals + + def get_frees(self): + """Return a tuple of free variables in the function. + """ + if self.__frees is None: + is_free = lambda x:((x >> SCOPE_OFF) & SCOPE_MASK) == FREE + self.__frees = self.__idents_matching(is_free) + return self.__frees + + +class Class(SymbolTable): + + __methods = None + + def get_methods(self): + """Return a tuple of methods declared in the class. + """ + if self.__methods is None: + d = {} + for st in self._table.children: + d[st.name] = 1 + self.__methods = tuple(d) + return self.__methods + + +class Symbol: + + def __init__(self, name, flags, namespaces=None, *, module_scope=False): + self.__name = name + self.__flags = flags + self.__scope = (flags >> SCOPE_OFF) & SCOPE_MASK # like PyST_GetScope() + self.__namespaces = namespaces or () + self.__module_scope = module_scope + + def __repr__(self): + return "<symbol {0!r}>".format(self.__name) + + def get_name(self): + """Return a name of a symbol. + """ + return self.__name + + def is_referenced(self): + """Return *True* if the symbol is used in + its block. + """ + return bool(self.__flags & _symtable.USE) + + def is_parameter(self): + """Return *True* if the symbol is a parameter. + """ + return bool(self.__flags & DEF_PARAM) + + def is_global(self): + """Return *True* if the symbol is global. + """ + return bool(self.__scope in (GLOBAL_IMPLICIT, GLOBAL_EXPLICIT) + or (self.__module_scope and self.__flags & DEF_BOUND)) + + def is_nonlocal(self): + """Return *True* if the symbol is nonlocal.""" + return bool(self.__flags & DEF_NONLOCAL) + + def is_declared_global(self): + """Return *True* if the symbol is declared global + with a global statement.""" + return bool(self.__scope == GLOBAL_EXPLICIT) + + def is_local(self): + """Return *True* if the symbol is local. + """ + return bool(self.__scope in (LOCAL, CELL) + or (self.__module_scope and self.__flags & DEF_BOUND)) + + def is_annotated(self): + """Return *True* if the symbol is annotated. + """ + return bool(self.__flags & DEF_ANNOT) + + def is_free(self): + """Return *True* if a referenced symbol is + not assigned to. + """ + return bool(self.__scope == FREE) + + def is_imported(self): + """Return *True* if the symbol is created from + an import statement. + """ + return bool(self.__flags & DEF_IMPORT) + + def is_assigned(self): + """Return *True* if a symbol is assigned to.""" + return bool(self.__flags & DEF_LOCAL) + + def is_namespace(self): + """Returns *True* if name binding introduces new namespace. + + If the name is used as the target of a function or class + statement, this will be true. + + Note that a single name can be bound to multiple objects. If + is_namespace() is true, the name may also be bound to other + objects, like an int or list, that does not introduce a new + namespace. + """ + return bool(self.__namespaces) + + def get_namespaces(self): + """Return a list of namespaces bound to this name""" + return self.__namespaces + + def get_namespace(self): + """Return the single namespace bound to this name. + + Raises ValueError if the name is bound to multiple namespaces + or no namespace. + """ + if len(self.__namespaces) == 0: + raise ValueError("name is not bound to any namespaces") + elif len(self.__namespaces) > 1: + raise ValueError("name is bound to multiple namespaces") + else: + return self.__namespaces[0] + +if __name__ == "__main__": + import os, sys + with open(sys.argv[0]) as f: + src = f.read() + mod = symtable(src, os.path.split(sys.argv[0])[1], "exec") + for ident in mod.get_identifiers(): + info = mod.lookup(ident) + print(info, info.is_local(), info.is_namespace()) |