Class SemanticAnalyzer

mypy/semanal.py:375–8202

Semantically analyze parsed mypy files. The analyzer binds names and does various consistency checks for an AST. Note that type checking is performed as a separate pass.

class SemanticAnalyzer(
    NodeVisitor[None], SemanticAnalyzerInterface, SemanticAnalyzerPluginInterface, SplittingVisitor
):
    """Semantically analyze parsed mypy files.

    The analyzer binds names and does various consistency checks for an
    AST. Note that type checking is performed as a separate pass.
    """

    __deletable__ = ["patches", "options", "cur_mod_node"]

    # Module name space
    modules: dict[str, MypyFile]
    # Global name space for current module
    globals: SymbolTable
    # Names declared using "global" (separate set for each scope)
    global_decls: list[set[str]]
    # Names declared using "nonlocal" (separate set for each scope)
    nonlocal_decls: list[set[str]]
    # Local names of function scopes; None for non-function scopes.
    locals: list[SymbolTable | None]
    # Type of each scope (SCOPE_*, indexes match locals)
    scope_stack: list[int]
    # Nested block depths of scopes
    block_depth: list[int]
    # TypeInfo of directly enclosing class (or None)
    _type: TypeInfo | None = None
    # Stack of outer classes (the second tuple item contains tvars).
    type_stack: list[TypeInfo | None]
    # Type variables bound by the current scope, be it class or function
    tvar_scope: TypeVarLikeScope
    # Per-module options
    options: Options

    # Stack of functions being analyzed
    function_stack: list[FuncItem]

    # Set to True if semantic analysis defines a name, or replaces a
    # placeholder definition. If some iteration makes no progress,
    # there can be at most one additional final iteration (see below).
    progress = False
    deferred = False  # Set to true if another analysis pass is needed
    incomplete = False  # Set to true if current module namespace is missing things
    # Is this the final iteration of semantic analysis (where we report
    # unbound names due to cyclic definitions and should not defer)?
    _final_iteration = False
    # These names couldn't be added to the symbol table due to incomplete deps.
    # Note that missing names are per module, _not_ per namespace. This means that e.g.
    # a missing name at global scope will block adding same name at a class scope.
    # This should not affect correctness and is purely a performance issue,
    # since it can cause unnecessary deferrals. These are represented as
    # PlaceholderNodes in the symbol table. We use this to ensure that the first
    # definition takes precedence even if it's incomplete.
    #
    # Note that a star import adds a special name '*' to the set, this blocks
    # adding _any_ names in the current file.
    missing_names: list[set[str]]
    # Callbacks that will be called after semantic analysis to tweak things.