Function evaluate_current_expression

bpython/simpleeval.py:200–243

Return evaluated expression to the right of the dot of current attribute. Only evaluates builtin objects, and do any attribute lookup.

(
    cursor_offset: int, line: str, namespace: dict[str, Any] | None = None
)

def evaluate_current_expression(
    cursor_offset: int, line: str, namespace: dict[str, Any] | None = None
) -> Any:
    """
    Return evaluated expression to the right of the dot of current attribute.

    Only evaluates builtin objects, and do any attribute lookup.
    """
    # Builds asts from with increasing numbers of characters back from cursor.
    # Find the biggest valid ast.
    # Once our attribute access is found, return its .value subtree

    # in case attribute is blank, e.g. foo.| -> foo.xxx|
    temp_line = line[:cursor_offset] + "xxx" + line[cursor_offset:]
    temp_cursor = cursor_offset + 3
    temp_attribute = line_properties.current_expression_attribute(
        temp_cursor, temp_line
    )
    if temp_attribute is None:
        raise EvaluationError("No current attribute")
    attr_before_cursor = temp_line[temp_attribute.start : temp_cursor]

    def parse_trees(cursor_offset, line):
        for i in range(cursor_offset - 1, -1, -1):
            try:
                tree = ast.parse(line[i:cursor_offset])
                yield tree
            except SyntaxError:
                continue

    largest_ast = None
    for tree in parse_trees(temp_cursor, temp_line):
        attribute_access = find_attribute_with_name(tree, attr_before_cursor)
        if attribute_access:
            largest_ast = attribute_access.value

    if largest_ast is None:
        raise EvaluationError(
            "Corresponding ASTs to right of cursor are invalid"
        )
    try:
        return simple_eval(largest_ast, namespace)
    except ValueError:
        raise EvaluationError("Could not safely evaluate")


def evaluate_current_attribute(cursor_offset, line, namespace=None):