Files
RustPython/vm/src/vm.rs
2021-01-08 18:08:21 -06:00

1874 lines
64 KiB
Rust

//! Implement virtual machine to run instructions.
//!
//! See also:
//! https://github.com/ProgVal/pythonvm-rust/blob/master/src/processor/mod.rs
//!
use std::cell::{Cell, Ref, RefCell};
use std::collections::HashMap;
use std::collections::HashSet;
use std::fmt;
use crossbeam_utils::atomic::AtomicCell;
use num_traits::{Signed, ToPrimitive};
use crate::builtins::code::{self, PyCode, PyCodeRef};
use crate::builtins::dict::PyDictRef;
use crate::builtins::int::{PyInt, PyIntRef};
use crate::builtins::list::PyList;
use crate::builtins::module::{self, PyModule};
use crate::builtins::object;
use crate::builtins::pybool;
use crate::builtins::pystr::{PyStr, PyStrRef};
use crate::builtins::pytype::PyTypeRef;
use crate::builtins::tuple::{PyTuple, PyTupleTyped};
use crate::common::{hash::HashSecret, lock::PyMutex, rc::PyRc};
#[cfg(feature = "rustpython-compiler")]
use crate::compile::{self, CompileError, CompileErrorType, CompileOpts};
use crate::exceptions::{self, PyBaseException, PyBaseExceptionRef};
use crate::frame::{ExecutionResult, Frame, FrameRef};
use crate::function::{FuncArgs, IntoFuncArgs};
use crate::pyobject::{
BorrowValue, Either, IdProtocol, IntoPyObject, ItemProtocol, PyArithmaticValue, PyContext,
PyObject, PyObjectRef, PyRef, PyRefExact, PyResult, PyValue, TryFromObject, TryIntoRef,
TypeProtocol,
};
use crate::scope::Scope;
use crate::slots::PyComparisonOp;
use crate::{builtins, bytecode, frozen, import, iterator, stdlib, sysmodule};
// use objects::ects;
// Objects are live when they are on stack, or referenced by a name (for now)
/// Top level container of a python virtual machine. In theory you could
/// create more instances of this struct and have them operate fully isolated.
pub struct VirtualMachine {
pub builtins: PyObjectRef,
pub sys_module: PyObjectRef,
pub ctx: PyRc<PyContext>,
pub frames: RefCell<Vec<FrameRef>>,
pub wasm_id: Option<String>,
pub exceptions: RefCell<Vec<PyBaseExceptionRef>>,
pub import_func: PyObjectRef,
pub profile_func: RefCell<PyObjectRef>,
pub trace_func: RefCell<PyObjectRef>,
pub use_tracing: Cell<bool>,
pub recursion_limit: Cell<usize>,
pub signal_handlers: Option<Box<RefCell<[Option<PyObjectRef>; NSIG]>>>,
pub repr_guards: RefCell<HashSet<usize>>,
pub state: PyRc<PyGlobalState>,
pub initialized: bool,
}
pub(crate) mod thread {
use super::{PyObjectRef, TypeProtocol, VirtualMachine};
use itertools::Itertools;
use std::cell::RefCell;
use std::ptr::NonNull;
use std::thread_local;
thread_local! {
pub(super) static VM_STACK: RefCell<Vec<NonNull<VirtualMachine>>> = Vec::with_capacity(1).into();
}
pub fn enter_vm<R>(vm: &VirtualMachine, f: impl FnOnce() -> R) -> R {
VM_STACK.with(|vms| {
vms.borrow_mut().push(vm.into());
let ret = std::panic::catch_unwind(std::panic::AssertUnwindSafe(f));
vms.borrow_mut().pop();
ret.unwrap_or_else(|e| std::panic::resume_unwind(e))
})
}
pub fn with_vm<F, R>(obj: &PyObjectRef, f: F) -> R
where
F: Fn(&VirtualMachine) -> R,
{
let vm_owns_obj = |intp: NonNull<VirtualMachine>| {
// SAFETY: all references in VM_STACK should be valid
let vm = unsafe { intp.as_ref() };
obj.isinstance(&vm.ctx.types.object_type)
};
VM_STACK.with(|vms| {
let intp = match vms.borrow().iter().copied().exactly_one() {
Ok(x) => {
debug_assert!(vm_owns_obj(x));
x
}
Err(mut others) => others
.find(|x| vm_owns_obj(*x))
.unwrap_or_else(|| panic!("can't get a vm for {:?}; none on stack", obj)),
};
// SAFETY: all references in VM_STACK should be valid, and should not be changed or moved
// at least until this function returns and the stack unwinds to an enter_vm() call
let vm = unsafe { intp.as_ref() };
f(vm)
})
}
}
pub struct PyGlobalState {
pub settings: PySettings,
pub stdlib_inits: HashMap<String, stdlib::StdlibInitFunc, ahash::RandomState>,
pub frozen: HashMap<String, code::FrozenModule, ahash::RandomState>,
pub stacksize: AtomicCell<usize>,
pub thread_count: AtomicCell<usize>,
pub hash_secret: HashSecret,
pub atexit_funcs: PyMutex<Vec<(PyObjectRef, FuncArgs)>>,
}
pub const NSIG: usize = 64;
#[derive(Copy, Clone, PartialEq, Eq)]
pub enum InitParameter {
Internal,
External,
}
/// Struct containing all kind of settings for the python vm.
pub struct PySettings {
/// -d command line switch
pub debug: bool,
/// -i
pub inspect: bool,
/// -i, with no script
pub interactive: bool,
/// -O optimization switch counter
pub optimize: u8,
/// -s
pub no_user_site: bool,
/// -S
pub no_site: bool,
/// -E
pub ignore_environment: bool,
/// verbosity level (-v switch)
pub verbose: u8,
/// -q
pub quiet: bool,
/// -B
pub dont_write_bytecode: bool,
/// -b
pub bytes_warning: u64,
/// -Xfoo[=bar]
pub xopts: Vec<(String, Option<String>)>,
/// -I
pub isolated: bool,
/// -Xdev
pub dev_mode: bool,
/// -Wfoo
pub warnopts: Vec<String>,
/// Environment PYTHONPATH and RUSTPYTHONPATH:
pub path_list: Vec<String>,
/// sys.argv
pub argv: Vec<String>,
/// PYTHONHASHSEED=x
pub hash_seed: Option<u32>,
}
/// Trace events for sys.settrace and sys.setprofile.
enum TraceEvent {
Call,
Return,
}
impl fmt::Display for TraceEvent {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
use TraceEvent::*;
match self {
Call => write!(f, "call"),
Return => write!(f, "return"),
}
}
}
/// Sensible default settings.
impl Default for PySettings {
fn default() -> Self {
PySettings {
debug: false,
inspect: false,
interactive: false,
optimize: 0,
no_user_site: false,
no_site: false,
ignore_environment: false,
verbose: 0,
quiet: false,
dont_write_bytecode: false,
bytes_warning: 0,
xopts: vec![],
isolated: false,
dev_mode: false,
warnopts: vec![],
path_list: vec![],
argv: vec![],
hash_seed: None,
}
}
}
impl VirtualMachine {
/// Create a new `VirtualMachine` structure.
fn new(settings: PySettings) -> VirtualMachine {
flame_guard!("new VirtualMachine");
let ctx = PyContext::new();
// make a new module without access to the vm; doesn't
// set __spec__, __loader__, etc. attributes
let new_module =
|dict| PyObject::new(PyModule {}, ctx.types.module_type.clone(), Some(dict));
// Hard-core modules:
let builtins_dict = ctx.new_dict();
let builtins = new_module(builtins_dict.clone());
let sysmod_dict = ctx.new_dict();
let sysmod = new_module(sysmod_dict.clone());
let import_func = ctx.none();
let profile_func = RefCell::new(ctx.none());
let trace_func = RefCell::new(ctx.none());
// hack to get around const array repeat expressions, rust issue #79270
const NONE: Option<PyObjectRef> = None;
let signal_handlers = RefCell::new([NONE; NSIG]);
let stdlib_inits = stdlib::get_module_inits();
let hash_secret = match settings.hash_seed {
Some(seed) => HashSecret::new(seed),
None => rand::random(),
};
let mut vm = VirtualMachine {
builtins,
sys_module: sysmod,
ctx: PyRc::new(ctx),
frames: RefCell::new(vec![]),
wasm_id: None,
exceptions: RefCell::new(vec![]),
import_func,
profile_func,
trace_func,
use_tracing: Cell::new(false),
recursion_limit: Cell::new(if cfg!(debug_assertions) { 256 } else { 512 }),
signal_handlers: Some(Box::new(signal_handlers)),
repr_guards: RefCell::default(),
state: PyRc::new(PyGlobalState {
settings,
stdlib_inits,
frozen: HashMap::default(),
stacksize: AtomicCell::new(0),
thread_count: AtomicCell::new(0),
hash_secret,
atexit_funcs: PyMutex::default(),
}),
initialized: false,
};
let frozen = frozen::get_module_inits(&vm);
PyRc::get_mut(&mut vm.state).unwrap().frozen = frozen;
module::init_module_dict(
&vm,
&builtins_dict,
vm.ctx.new_str("builtins"),
vm.ctx.none(),
);
module::init_module_dict(&vm, &sysmod_dict, vm.ctx.new_str("sys"), vm.ctx.none());
vm
}
fn initialize(&mut self, initialize_parameter: InitParameter) {
flame_guard!("init VirtualMachine");
if self.initialized {
panic!("Double Initialize Error");
}
builtins::make_module(self, self.builtins.clone());
sysmodule::make_module(self, self.sys_module.clone(), self.builtins.clone());
let mut inner_init = || -> PyResult<()> {
#[cfg(not(target_arch = "wasm32"))]
import::import_builtin(self, "_signal")?;
#[cfg(any(not(target_arch = "wasm32"), target_os = "wasi"))]
{
// this isn't fully compatible with CPython; it imports "io" and sets
// builtins.open to io.OpenWrapper, but this is easier, since it doesn't
// require the Python stdlib to be present
let io = import::import_builtin(self, "_io")?;
let set_stdio = |name, fd, mode: &str| {
let stdio = crate::stdlib::io::open(
self.ctx.new_int(fd),
Some(mode),
Default::default(),
self,
)?;
self.set_attr(
&self.sys_module,
format!("__{}__", name), // e.g. __stdin__
stdio.clone(),
)?;
self.set_attr(&self.sys_module, name, stdio)?;
Ok(())
};
set_stdio("stdin", 0, "r")?;
set_stdio("stdout", 1, "w")?;
set_stdio("stderr", 2, "w")?;
let io_open = self.get_attribute(io, "open")?;
self.set_attr(&self.builtins, "open", io_open)?;
}
import::init_importlib(self, initialize_parameter)?;
Ok(())
};
let res = inner_init();
self.expect_pyresult(res, "initializiation failed");
self.initialized = true;
}
/// Can only be used in the initialization closure passed to [`Interpreter::new_with_init`]
pub fn add_native_module(&mut self, name: String, module: stdlib::StdlibInitFunc) {
let state = PyRc::get_mut(&mut self.state)
.expect("can't add_native_module when there are multiple threads");
state.stdlib_inits.insert(name, module);
}
/// Can only be used in the initialization closure passed to [`Interpreter::new_with_init`]
pub fn add_frozen<I>(&mut self, frozen: I)
where
I: IntoIterator<Item = (String, bytecode::FrozenModule)>,
{
let frozen = frozen::map_frozen(self, frozen).collect::<Vec<_>>();
let state = PyRc::get_mut(&mut self.state)
.expect("can't add_frozen when there are multiple threads");
state.frozen.extend(frozen);
}
/// Start a new thread with access to the same interpreter.
///
/// # Note
///
/// If you return a `PyObjectRef` (or a type that contains one) from `F`, and don't `join()`
/// on the thread, there is a possibility that that thread will panic as `PyObjectRef`'s `Drop`
/// implementation tries to run the `__del__` destructor of a python object but finds that it's
/// not in the context of any vm.
#[cfg(feature = "threading")]
pub fn start_thread<F, R>(&self, f: F) -> std::thread::JoinHandle<R>
where
F: FnOnce(&VirtualMachine) -> R,
F: Send + 'static,
R: Send + 'static,
{
let thread = self.new_thread();
std::thread::spawn(|| thread.run(f))
}
/// Create a new VM thread that can be passed to a function like [`std::thread::spawn`]
/// to use the same interpreter on a different thread. Note that if you just want to
/// use this with `thread::spawn`, you can use
/// [`vm.start_thread()`](`VirtualMachine::start_thread`) as a convenience.
///
/// # Usage
///
/// ```
/// # rustpython_vm::Interpreter::default().enter(|vm| {
/// use std::thread::Builder;
/// let handle = Builder::new()
/// .name("my thread :)".into())
/// .spawn(vm.new_thread().make_spawn_func(|vm| vm.ctx.none()))
/// .expect("couldn't spawn thread");
/// let returned_obj = handle.join().expect("thread panicked");
/// assert!(vm.is_none(&returned_obj));
/// # })
/// ```
///
/// Note: this function is safe, but running the returned PyThread in the same
/// thread context (i.e. with the same thread-local storage) doesn't have any
/// specific guaranteed behavior.
#[cfg(feature = "threading")]
pub fn new_thread(&self) -> PyThread {
let thread_vm = VirtualMachine {
builtins: self.builtins.clone(),
sys_module: self.sys_module.clone(),
ctx: self.ctx.clone(),
frames: RefCell::new(vec![]),
wasm_id: self.wasm_id.clone(),
exceptions: RefCell::new(vec![]),
import_func: self.import_func.clone(),
profile_func: RefCell::new(self.ctx.none()),
trace_func: RefCell::new(self.ctx.none()),
use_tracing: Cell::new(false),
recursion_limit: self.recursion_limit.clone(),
signal_handlers: None,
repr_guards: RefCell::default(),
state: self.state.clone(),
initialized: self.initialized,
};
PyThread { thread_vm }
}
pub fn run_atexit_funcs(&self) -> PyResult<()> {
let mut last_exc = None;
for (func, args) in self.state.atexit_funcs.lock().drain(..).rev() {
if let Err(e) = self.invoke(&func, args) {
last_exc = Some(e.clone());
if !e.isinstance(&self.ctx.exceptions.system_exit) {
writeln!(sysmodule::PyStderr(self), "Error in atexit._run_exitfuncs:");
exceptions::print_exception(self, e);
}
}
}
match last_exc {
None => Ok(()),
Some(e) => Err(e),
}
}
pub fn run_code_obj(&self, code: PyCodeRef, scope: Scope) -> PyResult {
let frame =
Frame::new(code, scope, self.builtins.dict().unwrap(), &[], self).into_ref(self);
self.run_frame_full(frame)
}
pub fn run_frame_full(&self, frame: FrameRef) -> PyResult {
match self.run_frame(frame)? {
ExecutionResult::Return(value) => Ok(value),
_ => panic!("Got unexpected result from function"),
}
}
pub fn with_frame<R, F: FnOnce(FrameRef) -> PyResult<R>>(
&self,
frame: FrameRef,
f: F,
) -> PyResult<R> {
self.check_recursive_call("")?;
self.frames.borrow_mut().push(frame.clone());
let result = f(frame);
// defer dec frame
let _popped = self.frames.borrow_mut().pop();
result
}
pub fn run_frame(&self, frame: FrameRef) -> PyResult<ExecutionResult> {
self.with_frame(frame, |f| f.run(self))
}
fn check_recursive_call(&self, _where: &str) -> PyResult<()> {
if self.frames.borrow().len() > self.recursion_limit.get() {
Err(self.new_recursion_error(format!("maximum recursion depth exceeded {}", _where)))
} else {
Ok(())
}
}
pub fn current_frame(&self) -> Option<Ref<FrameRef>> {
let frames = self.frames.borrow();
if frames.is_empty() {
None
} else {
Some(Ref::map(self.frames.borrow(), |frames| {
frames.last().unwrap()
}))
}
}
pub fn current_locals(&self) -> PyResult<PyDictRef> {
self.current_frame()
.expect("called current_locals but no frames on the stack")
.locals(self)
}
pub fn current_globals(&self) -> Ref<PyDictRef> {
let frame = self
.current_frame()
.expect("called current_globals but no frames on the stack");
Ref::map(frame, |f| &f.globals)
}
pub fn try_class(&self, module: &str, class: &str) -> PyResult<PyTypeRef> {
let class = self
.get_attribute(self.import(module, None, 0)?, class)?
.downcast()
.expect("not a class");
Ok(class)
}
pub fn class(&self, module: &str, class: &str) -> PyTypeRef {
let module = self
.import(module, None, 0)
.unwrap_or_else(|_| panic!("unable to import {}", module));
let class = self
.get_attribute(module.clone(), class)
.unwrap_or_else(|_| panic!("module {} has no class {}", module, class));
class.downcast().expect("not a class")
}
/// Create a new python object
pub fn new_pyobj<T: IntoPyObject>(&self, value: T) -> PyObjectRef {
value.into_pyobject(self)
}
pub fn new_code_object(&self, code: impl code::IntoCodeObject) -> PyCodeRef {
self.ctx.new_code_object(code.into_codeobj(self))
}
pub fn new_module(&self, name: &str, dict: PyDictRef) -> PyObjectRef {
module::init_module_dict(
self,
&dict,
self.new_pyobj(name.to_owned()),
self.ctx.none(),
);
PyObject::new(PyModule {}, self.ctx.types.module_type.clone(), Some(dict))
}
/// Instantiate an exception with arguments.
/// This function should only be used with builtin exception types; if a user-defined exception
/// type is passed in, it may not be fully initialized; try using [`exceptions::invoke`](invoke)
/// or [`exceptions::ExceptionCtor`](ctor) instead.
///
/// [invoke]: rustpython_vm::exceptions::invoke
/// [ctor]: rustpython_vm::exceptions::ExceptionCtor
pub fn new_exception(&self, exc_type: PyTypeRef, args: Vec<PyObjectRef>) -> PyBaseExceptionRef {
// TODO: add repr of args into logging?
vm_trace!("New exception created: {}", exc_type.name);
PyRef::new_ref(
PyBaseException::new(args, self),
exc_type,
Some(self.ctx.new_dict()),
)
}
/// Instantiate an exception with no arguments.
/// This function should only be used with builtin exception types; if a user-defined exception
/// type is passed in, it may not be fully initialized; try using [`exceptions::invoke`](invoke)
/// or [`exceptions::ExceptionCtor`](ctor) instead.
///
/// [invoke]: rustpython_vm::exceptions::invoke
/// [ctor]: rustpython_vm::exceptions::ExceptionCtor
pub fn new_exception_empty(&self, exc_type: PyTypeRef) -> PyBaseExceptionRef {
self.new_exception(exc_type, vec![])
}
/// Instantiate an exception with `msg` as the only argument.
/// This function should only be used with builtin exception types; if a user-defined exception
/// type is passed in, it may not be fully initialized; try using [`exceptions::invoke`](invoke)
/// or [`exceptions::ExceptionCtor`](ctor) instead.
///
/// [invoke]: rustpython_vm::exceptions::invoke
/// [ctor]: rustpython_vm::exceptions::ExceptionCtor
pub fn new_exception_msg(&self, exc_type: PyTypeRef, msg: String) -> PyBaseExceptionRef {
self.new_exception(exc_type, vec![self.ctx.new_str(msg)])
}
pub fn new_lookup_error(&self, msg: String) -> PyBaseExceptionRef {
let lookup_error = self.ctx.exceptions.lookup_error.clone();
self.new_exception_msg(lookup_error, msg)
}
pub fn new_attribute_error(&self, msg: String) -> PyBaseExceptionRef {
let attribute_error = self.ctx.exceptions.attribute_error.clone();
self.new_exception_msg(attribute_error, msg)
}
pub fn new_type_error(&self, msg: String) -> PyBaseExceptionRef {
let type_error = self.ctx.exceptions.type_error.clone();
self.new_exception_msg(type_error, msg)
}
pub fn new_name_error(&self, msg: String) -> PyBaseExceptionRef {
let name_error = self.ctx.exceptions.name_error.clone();
self.new_exception_msg(name_error, msg)
}
pub fn new_unsupported_binop_error(
&self,
a: &PyObjectRef,
b: &PyObjectRef,
op: &str,
) -> PyBaseExceptionRef {
self.new_type_error(format!(
"Unsupported operand types for '{}': '{}' and '{}'",
op,
a.class().name,
b.class().name
))
}
pub fn new_unsupported_ternop_error(
&self,
a: &PyObjectRef,
b: &PyObjectRef,
c: &PyObjectRef,
op: &str,
) -> PyBaseExceptionRef {
self.new_type_error(format!(
"Unsupported operand types for '{}': '{}', '{}', and '{}'",
op,
a.class().name,
b.class().name,
c.class().name
))
}
pub fn new_os_error(&self, msg: String) -> PyBaseExceptionRef {
let os_error = self.ctx.exceptions.os_error.clone();
self.new_exception_msg(os_error, msg)
}
pub fn new_unicode_decode_error(&self, msg: String) -> PyBaseExceptionRef {
let unicode_decode_error = self.ctx.exceptions.unicode_decode_error.clone();
self.new_exception_msg(unicode_decode_error, msg)
}
pub fn new_unicode_encode_error(&self, msg: String) -> PyBaseExceptionRef {
let unicode_encode_error = self.ctx.exceptions.unicode_encode_error.clone();
self.new_exception_msg(unicode_encode_error, msg)
}
/// Create a new python ValueError object. Useful for raising errors from
/// python functions implemented in rust.
pub fn new_value_error(&self, msg: String) -> PyBaseExceptionRef {
let value_error = self.ctx.exceptions.value_error.clone();
self.new_exception_msg(value_error, msg)
}
pub fn new_buffer_error(&self, msg: String) -> PyBaseExceptionRef {
let buffer_error = self.ctx.exceptions.buffer_error.clone();
self.new_exception_msg(buffer_error, msg)
}
pub fn new_key_error(&self, obj: PyObjectRef) -> PyBaseExceptionRef {
let key_error = self.ctx.exceptions.key_error.clone();
self.new_exception(key_error, vec![obj])
}
pub fn new_index_error(&self, msg: String) -> PyBaseExceptionRef {
let index_error = self.ctx.exceptions.index_error.clone();
self.new_exception_msg(index_error, msg)
}
pub fn new_not_implemented_error(&self, msg: String) -> PyBaseExceptionRef {
let not_implemented_error = self.ctx.exceptions.not_implemented_error.clone();
self.new_exception_msg(not_implemented_error, msg)
}
pub fn new_recursion_error(&self, msg: String) -> PyBaseExceptionRef {
let recursion_error = self.ctx.exceptions.recursion_error.clone();
self.new_exception_msg(recursion_error, msg)
}
pub fn new_zero_division_error(&self, msg: String) -> PyBaseExceptionRef {
let zero_division_error = self.ctx.exceptions.zero_division_error.clone();
self.new_exception_msg(zero_division_error, msg)
}
pub fn new_overflow_error(&self, msg: String) -> PyBaseExceptionRef {
let overflow_error = self.ctx.exceptions.overflow_error.clone();
self.new_exception_msg(overflow_error, msg)
}
#[cfg(feature = "rustpython-compiler")]
pub fn new_syntax_error(&self, error: &CompileError) -> PyBaseExceptionRef {
let syntax_error_type = match &error.error {
CompileErrorType::Parse(p) if p.is_indentation_error() => {
self.ctx.exceptions.indentation_error.clone()
}
CompileErrorType::Parse(p) if p.is_tab_error() => self.ctx.exceptions.tab_error.clone(),
_ => self.ctx.exceptions.syntax_error.clone(),
};
let syntax_error = self.new_exception_msg(syntax_error_type, error.to_string());
let lineno = self.ctx.new_int(error.location.row());
let offset = self.ctx.new_int(error.location.column());
self.set_attr(syntax_error.as_object(), "lineno", lineno)
.unwrap();
self.set_attr(syntax_error.as_object(), "offset", offset)
.unwrap();
self.set_attr(
syntax_error.as_object(),
"text",
error.statement.clone().into_pyobject(self),
)
.unwrap();
self.set_attr(
syntax_error.as_object(),
"filename",
self.ctx.new_str(error.source_path.clone()),
)
.unwrap();
syntax_error
}
pub fn new_import_error(
&self,
msg: String,
name: impl TryIntoRef<PyStr>,
) -> PyBaseExceptionRef {
let import_error = self.ctx.exceptions.import_error.clone();
let exc = self.new_exception_msg(import_error, msg);
self.set_attr(exc.as_object(), "name", name.try_into_ref(self).unwrap())
.unwrap();
exc
}
pub fn new_runtime_error(&self, msg: String) -> PyBaseExceptionRef {
let runtime_error = self.ctx.exceptions.runtime_error.clone();
self.new_exception_msg(runtime_error, msg)
}
pub fn new_stop_iteration(&self) -> PyBaseExceptionRef {
let stop_iteration_type = self.ctx.exceptions.stop_iteration.clone();
self.new_exception_empty(stop_iteration_type)
}
// TODO: #[track_caller] when stabilized
fn _py_panic_failed(&self, exc: PyBaseExceptionRef, msg: &str) -> ! {
#[cfg(not(all(target_arch = "wasm32", not(target_os = "wasi"))))]
{
let show_backtrace = std::env::var_os("RUST_BACKTRACE").map_or(false, |v| &v != "0");
let after = if show_backtrace {
exceptions::print_exception(self, exc);
"exception backtrace above"
} else {
"run with RUST_BACKTRACE=1 to see Python backtrace"
};
panic!("{}; {}", msg, after)
}
#[cfg(all(target_arch = "wasm32", not(target_os = "wasi")))]
{
use wasm_bindgen::prelude::*;
#[wasm_bindgen]
extern "C" {
#[wasm_bindgen(js_namespace = console)]
fn error(s: &str);
}
let mut s = Vec::<u8>::new();
exceptions::write_exception(&mut s, self, &exc).unwrap();
error(std::str::from_utf8(&s).unwrap());
panic!("{}; exception backtrace above", msg)
}
}
pub fn unwrap_pyresult<T>(&self, result: PyResult<T>) -> T {
result.unwrap_or_else(|exc| {
self._py_panic_failed(exc, "called `vm.unwrap_pyresult()` on an `Err` value")
})
}
pub fn expect_pyresult<T>(&self, result: PyResult<T>, msg: &str) -> T {
result.unwrap_or_else(|exc| self._py_panic_failed(exc, msg))
}
pub fn new_scope_with_builtins(&self) -> Scope {
Scope::with_builtins(None, self.ctx.new_dict(), self)
}
/// Test whether a python object is `None`.
pub fn is_none(&self, obj: &PyObjectRef) -> bool {
obj.is(&self.ctx.none)
}
pub fn option_if_none(&self, obj: PyObjectRef) -> Option<PyObjectRef> {
if self.is_none(&obj) {
None
} else {
Some(obj)
}
}
pub fn unwrap_or_none(&self, obj: Option<PyObjectRef>) -> PyObjectRef {
obj.unwrap_or_else(|| self.ctx.none())
}
// Container of the virtual machine state:
pub fn to_str(&self, obj: &PyObjectRef) -> PyResult<PyStrRef> {
if obj.class().is(&self.ctx.types.str_type) {
Ok(obj.clone().downcast().unwrap())
} else {
let s = self.call_method(&obj, "__str__", ())?;
PyStrRef::try_from_object(self, s)
}
}
pub fn to_pystr<'a, T: Into<&'a PyObjectRef>>(&'a self, obj: T) -> PyResult<String> {
let py_str_obj = self.to_str(obj.into())?;
Ok(py_str_obj.borrow_value().to_owned())
}
pub fn to_repr(&self, obj: &PyObjectRef) -> PyResult<PyStrRef> {
let repr = self.call_method(obj, "__repr__", ())?;
TryFromObject::try_from_object(self, repr)
}
pub fn to_index_opt(&self, obj: PyObjectRef) -> Option<PyResult<PyIntRef>> {
match obj.downcast() {
Ok(val) => Some(Ok(val)),
Err(obj) => self.get_method(obj, "__index__").map(|index| {
// TODO: returning strict subclasses of int in __index__ is deprecated
self.invoke(&index?, ())?.downcast().map_err(|bad| {
self.new_type_error(format!(
"__index__ returned non-int (type {})",
bad.class().name
))
})
}),
}
}
pub fn to_index(&self, obj: &PyObjectRef) -> PyResult<PyIntRef> {
self.to_index_opt(obj.clone()).unwrap_or_else(|| {
Err(self.new_type_error(format!(
"'{}' object cannot be interpreted as an integer",
obj.class().name
)))
})
}
#[inline]
pub fn import(
&self,
module: impl TryIntoRef<PyStr>,
from_list: Option<PyTupleTyped<PyStrRef>>,
level: usize,
) -> PyResult {
self._import_inner(module.try_into_ref(self)?, from_list, level)
}
fn _import_inner(
&self,
module: PyStrRef,
from_list: Option<PyTupleTyped<PyStrRef>>,
level: usize,
) -> PyResult {
// if the import inputs seem weird, e.g a package import or something, rather than just
// a straight `import ident`
let weird = module.borrow_value().contains('.')
|| level != 0
|| from_list
.as_ref()
.map_or(false, |x| !x.borrow_value().is_empty());
let cached_module = if weird {
None
} else {
let sys_modules = self.get_attribute(self.sys_module.clone(), "modules")?;
sys_modules.get_item(module.clone(), self).ok()
};
match cached_module {
Some(cached_module) => {
if self.is_none(&cached_module) {
Err(self.new_import_error(
format!("import of {} halted; None in sys.modules", module),
module,
))
} else {
Ok(cached_module)
}
}
None => {
let import_func = self
.get_attribute(self.builtins.clone(), "__import__")
.map_err(|_| {
self.new_import_error("__import__ not found".to_owned(), module.clone())
})?;
let (locals, globals) = if let Some(frame) = self.current_frame() {
(Some(frame.locals.clone()), Some(frame.globals.clone()))
} else {
(None, None)
};
let from_list = match from_list {
Some(tup) => tup.into_pyobject(self),
None => self.ctx.new_tuple(vec![]),
};
self.invoke(&import_func, (module, globals, locals, from_list, level))
.map_err(|exc| import::remove_importlib_frames(self, &exc))
}
}
}
/// Determines if `obj` is an instance of `cls`, either directly, indirectly or virtually via
/// the __instancecheck__ magic method.
pub fn isinstance(&self, obj: &PyObjectRef, cls: &PyTypeRef) -> PyResult<bool> {
// cpython first does an exact check on the type, although documentation doesn't state that
// https://github.com/python/cpython/blob/a24107b04c1277e3c1105f98aff5bfa3a98b33a0/Objects/abstract.c#L2408
if obj.class().is(cls) {
Ok(true)
} else {
let ret = self.call_method(cls.as_object(), "__instancecheck__", (obj.clone(),))?;
pybool::boolval(self, ret)
}
}
/// Determines if `subclass` is a subclass of `cls`, either directly, indirectly or virtually
/// via the __subclasscheck__ magic method.
pub fn issubclass(&self, subclass: &PyTypeRef, cls: &PyTypeRef) -> PyResult<bool> {
let ret = self.call_method(cls.as_object(), "__subclasscheck__", (subclass.clone(),))?;
pybool::boolval(self, ret)
}
pub fn call_get_descriptor_specific(
&self,
descr: PyObjectRef,
obj: Option<PyObjectRef>,
cls: Option<PyObjectRef>,
) -> Option<PyResult> {
let descr_get = descr.class().mro_find_map(|cls| cls.slots.descr_get.load());
descr_get.map(|descr_get| descr_get(descr, obj, cls, self))
}
pub fn call_get_descriptor(&self, descr: PyObjectRef, obj: PyObjectRef) -> Option<PyResult> {
let cls = obj.clone_class().into_object();
self.call_get_descriptor_specific(descr, Some(obj), Some(cls))
}
pub fn call_if_get_descriptor(&self, attr: PyObjectRef, obj: PyObjectRef) -> PyResult {
self.call_get_descriptor(attr.clone(), obj)
.unwrap_or(Ok(attr))
}
pub fn call_method<T>(&self, obj: &PyObjectRef, method_name: &str, args: T) -> PyResult
where
T: IntoFuncArgs,
{
flame_guard!(format!("call_method({:?})", method_name));
// This is only used in the vm for magic methods, which use a greatly simplified attribute lookup.
match obj.get_class_attr(method_name) {
Some(func) => {
vm_trace!("vm.call_method {:?} {:?} -> {:?}", obj, method_name, func);
let wrapped = self.call_if_get_descriptor(func, obj.clone())?;
self.invoke(&wrapped, args)
}
None => Err(self.new_type_error(format!("Unsupported method: {}", method_name))),
}
}
fn _invoke(&self, callable: &PyObjectRef, args: FuncArgs) -> PyResult {
vm_trace!("Invoke: {:?} {:?}", callable, args);
let slot_call = callable.class().mro_find_map(|cls| cls.slots.call.load());
match slot_call {
Some(slot_call) => {
self.trace_event(TraceEvent::Call)?;
let result = slot_call(callable, args, self);
self.trace_event(TraceEvent::Return)?;
result
}
None => Err(self.new_type_error(format!(
"'{}' object is not callable",
callable.class().name
))),
}
}
#[inline]
pub fn invoke<T>(&self, func_ref: &PyObjectRef, args: T) -> PyResult
where
T: IntoFuncArgs,
{
self._invoke(func_ref, args.into_args(self))
}
/// Call registered trace function.
#[inline]
fn trace_event(&self, event: TraceEvent) -> PyResult<()> {
if self.use_tracing.get() {
self._trace_event_inner(event)
} else {
Ok(())
}
}
fn _trace_event_inner(&self, event: TraceEvent) -> PyResult<()> {
let trace_func = self.trace_func.borrow().clone();
let profile_func = self.profile_func.borrow().clone();
if self.is_none(&trace_func) && self.is_none(&profile_func) {
return Ok(());
}
let frame_ref = self.current_frame();
if frame_ref.is_none() {
return Ok(());
}
let frame = frame_ref.unwrap().as_object().clone();
let event = self.ctx.new_str(event.to_string());
let args = vec![frame, event, self.ctx.none()];
// temporarily disable tracing, during the call to the
// tracing function itself.
if !self.is_none(&trace_func) {
self.use_tracing.set(false);
let res = self.invoke(&trace_func, args.clone());
self.use_tracing.set(true);
res?;
}
if !self.is_none(&profile_func) {
self.use_tracing.set(false);
let res = self.invoke(&profile_func, args);
self.use_tracing.set(true);
res?;
}
Ok(())
}
pub fn extract_elements<T: TryFromObject>(&self, value: &PyObjectRef) -> PyResult<Vec<T>> {
// Extract elements from item, if possible:
let cls = value.class();
if cls.is(&self.ctx.types.tuple_type) {
value
.payload::<PyTuple>()
.unwrap()
.borrow_value()
.iter()
.map(|obj| T::try_from_object(self, obj.clone()))
.collect()
} else if cls.is(&self.ctx.types.list_type) {
value
.payload::<PyList>()
.unwrap()
.borrow_value()
.iter()
.map(|obj| T::try_from_object(self, obj.clone()))
.collect()
} else {
let iter = iterator::get_iter(self, value.clone())?;
iterator::get_all(self, &iter)
}
}
pub fn map_iterable_object<F, R>(
&self,
obj: &PyObjectRef,
mut f: F,
) -> PyResult<PyResult<Vec<R>>>
where
F: FnMut(PyObjectRef) -> PyResult<R>,
{
match_class!(match obj {
ref l @ PyList => {
let mut i: usize = 0;
let mut results = Vec::with_capacity(l.borrow_value().len());
loop {
let elem = {
let elements = &*l.borrow_value();
if i >= elements.len() {
results.shrink_to_fit();
return Ok(Ok(results));
} else {
elements[i].clone()
}
// free the lock
};
match f(elem) {
Ok(result) => results.push(result),
Err(err) => return Ok(Err(err)),
}
i += 1;
}
}
ref t @ PyTuple => Ok(t.borrow_value().iter().cloned().map(f).collect()),
// TODO: put internal iterable type
obj => {
let iter = iterator::get_iter(self, obj.clone())?;
Ok(iterator::try_map(self, &iter, f))
}
})
}
// get_attribute should be used for full attribute access (usually from user code).
#[cfg_attr(feature = "flame-it", flame("VirtualMachine"))]
pub fn get_attribute<T>(&self, obj: PyObjectRef, attr_name: T) -> PyResult
where
T: TryIntoRef<PyStr>,
{
let attr_name = attr_name.try_into_ref(self)?;
vm_trace!("vm.__getattribute__: {:?} {:?}", obj, attr_name);
let getattro = obj
.class()
.mro_find_map(|cls| cls.slots.getattro.load())
.unwrap();
getattro(obj, attr_name, self)
}
pub fn set_attr<K, V>(&self, obj: &PyObjectRef, attr_name: K, attr_value: V) -> PyResult
where
K: TryIntoRef<PyStr>,
V: Into<PyObjectRef>,
{
let attr_name = attr_name.try_into_ref(self)?;
self.call_method(obj, "__setattr__", (attr_name, attr_value.into()))
}
pub fn del_attr(&self, obj: &PyObjectRef, attr_name: PyObjectRef) -> PyResult<()> {
self.call_method(&obj, "__delattr__", (attr_name,))?;
Ok(())
}
// get_method should be used for internal access to magic methods (by-passing
// the full getattribute look-up.
pub fn get_method_or_type_error<F>(
&self,
obj: PyObjectRef,
method_name: &str,
err_msg: F,
) -> PyResult
where
F: FnOnce() -> String,
{
match obj.get_class_attr(method_name) {
Some(method) => self.call_if_get_descriptor(method, obj),
None => Err(self.new_type_error(err_msg())),
}
}
/// May return exception, if `__get__` descriptor raises one
pub fn get_method(&self, obj: PyObjectRef, method_name: &str) -> Option<PyResult> {
let method = obj.get_class_attr(method_name)?;
Some(self.call_if_get_descriptor(method, obj))
}
/// Calls a method on `obj` passing `arg`, if the method exists.
///
/// Otherwise, or if the result is the special `NotImplemented` built-in constant,
/// calls `unsupported` to determine fallback value.
pub fn call_or_unsupported<F>(
&self,
obj: &PyObjectRef,
arg: &PyObjectRef,
method: &str,
unsupported: F,
) -> PyResult
where
F: Fn(&VirtualMachine, &PyObjectRef, &PyObjectRef) -> PyResult,
{
if let Some(method_or_err) = self.get_method(obj.clone(), method) {
let method = method_or_err?;
let result = self.invoke(&method, (arg.clone(),))?;
if let PyArithmaticValue::Implemented(x) = PyArithmaticValue::from_object(self, result)
{
return Ok(x);
}
}
unsupported(self, obj, arg)
}
/// Calls a method, falling back to its reflection with the operands
/// reversed, and then to the value provided by `unsupported`.
///
/// For example: the following:
///
/// `call_or_reflection(lhs, rhs, "__and__", "__rand__", unsupported)`
///
/// 1. Calls `__and__` with `lhs` and `rhs`.
/// 2. If above is not implemented, calls `__rand__` with `rhs` and `lhs`.
/// 3. If above is not implemented, invokes `unsupported` for the result.
pub fn call_or_reflection(
&self,
lhs: &PyObjectRef,
rhs: &PyObjectRef,
default: &str,
reflection: &str,
unsupported: fn(&VirtualMachine, &PyObjectRef, &PyObjectRef) -> PyResult,
) -> PyResult {
// Try to call the default method
self.call_or_unsupported(lhs, rhs, default, move |vm, lhs, rhs| {
// Try to call the reflection method
// don't call reflection method if operands are of the same type
if !lhs.class().is(&rhs.class()) {
vm.call_or_unsupported(rhs, lhs, reflection, |_, rhs, lhs| {
// switch them around again
unsupported(vm, lhs, rhs)
})
} else {
unsupported(vm, lhs, rhs)
}
})
}
pub fn generic_getattribute(&self, obj: PyObjectRef, name: PyStrRef) -> PyResult {
self.generic_getattribute_opt(obj.clone(), name.clone(), None)?
.ok_or_else(|| self.new_attribute_error(format!("{} has no attribute '{}'", obj, name)))
}
/// CPython _PyObject_GenericGetAttrWithDict
pub fn generic_getattribute_opt(
&self,
obj: PyObjectRef,
name_str: PyStrRef,
dict: Option<PyDictRef>,
) -> PyResult<Option<PyObjectRef>> {
let name = name_str.borrow_value();
let cls_attr = obj.class().get_attr(name);
if let Some(ref attr) = cls_attr {
if attr.class().has_attr("__set__") {
if let Some(r) = self.call_get_descriptor(attr.clone(), obj.clone()) {
return r.map(Some);
}
}
}
let dict = dict.or_else(|| obj.dict());
let attr = if let Some(dict) = dict {
dict.get_item_option(name, self)?
} else {
None
};
if let Some(obj_attr) = attr {
Ok(Some(obj_attr))
} else if let Some(attr) = cls_attr {
self.call_if_get_descriptor(attr, obj).map(Some)
} else if let Some(getter) = obj.clone_class().get_attr("__getattr__") {
self.invoke(&getter, (obj, name_str)).map(Some)
} else {
Ok(None)
}
}
pub fn is_callable(&self, obj: &PyObjectRef) -> bool {
obj.class()
.mro_find_map(|cls| cls.slots.call.load())
.is_some()
}
#[inline]
/// Checks for triggered signals and calls the appropriate handlers. A no-op on
/// platforms where signals are not supported.
pub fn check_signals(&self) -> PyResult<()> {
#[cfg(not(target_arch = "wasm32"))]
{
crate::stdlib::signal::check_signals(self)
}
#[cfg(target_arch = "wasm32")]
{
Ok(())
}
}
/// Returns a basic CompileOpts instance with options accurate to the vm. Used
/// as the CompileOpts for `vm.compile()`.
#[cfg(feature = "rustpython-compiler")]
pub fn compile_opts(&self) -> CompileOpts {
CompileOpts {
optimize: self.state.settings.optimize,
}
}
#[cfg(feature = "rustpython-compiler")]
pub fn compile(
&self,
source: &str,
mode: compile::Mode,
source_path: String,
) -> Result<PyCodeRef, CompileError> {
self.compile_with_opts(source, mode, source_path, self.compile_opts())
}
#[cfg(feature = "rustpython-compiler")]
pub fn compile_with_opts(
&self,
source: &str,
mode: compile::Mode,
source_path: String,
opts: CompileOpts,
) -> Result<PyCodeRef, CompileError> {
compile::compile(source, mode, source_path, opts)
.map(|code| PyCode::new(self.map_codeobj(code)).into_ref(self))
}
fn call_codec_func(
&self,
func: &str,
obj: PyObjectRef,
encoding: Option<PyStrRef>,
errors: Option<PyStrRef>,
) -> PyResult {
let codecsmodule = self.import("_codecs", None, 0)?;
let func = self.get_attribute(codecsmodule, func)?;
let mut args = vec![obj, encoding.into_pyobject(self)];
if let Some(errors) = errors {
args.push(errors.into_object());
}
self.invoke(&func, args)
}
pub fn decode(
&self,
obj: PyObjectRef,
encoding: Option<PyStrRef>,
errors: Option<PyStrRef>,
) -> PyResult {
self.call_codec_func("decode", obj, encoding, errors)
}
pub fn encode(
&self,
obj: PyObjectRef,
encoding: Option<PyStrRef>,
errors: Option<PyStrRef>,
) -> PyResult {
self.call_codec_func("encode", obj, encoding, errors)
}
pub fn _sub(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__sub__", "__rsub__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "-"))
})
}
pub fn _isub(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__isub__", |vm, a, b| {
vm.call_or_reflection(a, b, "__sub__", "__rsub__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "-="))
})
})
}
pub fn _add(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__add__", "__radd__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "+"))
})
}
pub fn _iadd(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__iadd__", |vm, a, b| {
vm.call_or_reflection(a, b, "__add__", "__radd__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "+="))
})
})
}
pub fn _mul(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__mul__", "__rmul__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "*"))
})
}
pub fn _imul(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__imul__", |vm, a, b| {
vm.call_or_reflection(a, b, "__mul__", "__rmul__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "*="))
})
})
}
pub fn _matmul(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__matmul__", "__rmatmul__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "@"))
})
}
pub fn _imatmul(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__imatmul__", |vm, a, b| {
vm.call_or_reflection(a, b, "__matmul__", "__rmatmul__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "@="))
})
})
}
pub fn _truediv(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__truediv__", "__rtruediv__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "/"))
})
}
pub fn _itruediv(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__itruediv__", |vm, a, b| {
vm.call_or_reflection(a, b, "__truediv__", "__rtruediv__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "/="))
})
})
}
pub fn _floordiv(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__floordiv__", "__rfloordiv__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "//"))
})
}
pub fn _ifloordiv(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__ifloordiv__", |vm, a, b| {
vm.call_or_reflection(a, b, "__floordiv__", "__rfloordiv__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "//="))
})
})
}
pub fn _pow(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__pow__", "__rpow__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "**"))
})
}
pub fn _ipow(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__ipow__", |vm, a, b| {
vm.call_or_reflection(a, b, "__pow__", "__rpow__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "**="))
})
})
}
pub fn _mod(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__mod__", "__rmod__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "%"))
})
}
pub fn _imod(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__imod__", |vm, a, b| {
vm.call_or_reflection(a, b, "__mod__", "__rmod__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "%="))
})
})
}
pub fn _lshift(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__lshift__", "__rlshift__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "<<"))
})
}
pub fn _ilshift(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__ilshift__", |vm, a, b| {
vm.call_or_reflection(a, b, "__lshift__", "__rlshift__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "<<="))
})
})
}
pub fn _rshift(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__rshift__", "__rrshift__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, ">>"))
})
}
pub fn _irshift(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__irshift__", |vm, a, b| {
vm.call_or_reflection(a, b, "__rshift__", "__rrshift__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, ">>="))
})
})
}
pub fn _xor(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__xor__", "__rxor__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "^"))
})
}
pub fn _ixor(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__ixor__", |vm, a, b| {
vm.call_or_reflection(a, b, "__xor__", "__rxor__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "^="))
})
})
}
pub fn _or(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__or__", "__ror__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "|"))
})
}
pub fn _ior(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__ior__", |vm, a, b| {
vm.call_or_reflection(a, b, "__or__", "__ror__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "|="))
})
})
}
pub fn _and(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_reflection(a, b, "__and__", "__rand__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "&"))
})
}
pub fn _iand(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult {
self.call_or_unsupported(a, b, "__iand__", |vm, a, b| {
vm.call_or_reflection(a, b, "__and__", "__rand__", |vm, a, b| {
Err(vm.new_unsupported_binop_error(a, b, "&="))
})
})
}
// Perform a comparison, raising TypeError when the requested comparison
// operator is not supported.
// see: CPython PyObject_RichCompare
fn _cmp(
&self,
v: &PyObjectRef,
w: &PyObjectRef,
op: PyComparisonOp,
) -> PyResult<Either<PyObjectRef, bool>> {
let swapped = op.swapped();
// TODO: _Py_EnterRecursiveCall(tstate, " in comparison")
let call_cmp = |obj: &PyObjectRef, other, op| {
let cmp = obj
.class()
.mro_find_map(|cls| cls.slots.cmp.load())
.unwrap();
Ok(match cmp(obj, other, op, self)? {
Either::A(obj) => PyArithmaticValue::from_object(self, obj).map(Either::A),
Either::B(arithmatic) => arithmatic.map(Either::B),
})
};
let mut checked_reverse_op = false;
let is_strict_subclass = {
let v_class = v.class();
let w_class = w.class();
!v_class.is(&w_class) && w_class.issubclass(&v_class)
};
if is_strict_subclass {
let res = call_cmp(w, v, swapped)?;
checked_reverse_op = true;
if let PyArithmaticValue::Implemented(x) = res {
return Ok(x);
}
}
if let PyArithmaticValue::Implemented(x) = call_cmp(v, w, op)? {
return Ok(x);
}
if !checked_reverse_op {
let res = call_cmp(w, v, swapped)?;
if let PyArithmaticValue::Implemented(x) = res {
return Ok(x);
}
}
match op {
PyComparisonOp::Eq => Ok(Either::B(v.is(&w))),
PyComparisonOp::Ne => Ok(Either::B(!v.is(&w))),
_ => Err(self.new_unsupported_binop_error(v, w, op.operator_token())),
}
// TODO: _Py_LeaveRecursiveCall(tstate);
}
pub fn bool_cmp(&self, a: &PyObjectRef, b: &PyObjectRef, op: PyComparisonOp) -> PyResult<bool> {
match self._cmp(a, b, op)? {
Either::A(obj) => pybool::boolval(self, obj),
Either::B(b) => Ok(b),
}
}
pub fn obj_cmp(&self, a: PyObjectRef, b: PyObjectRef, op: PyComparisonOp) -> PyResult {
self._cmp(&a, &b, op).map(|res| res.into_pyobject(self))
}
pub fn _hash(&self, obj: &PyObjectRef) -> PyResult<rustpython_common::hash::PyHash> {
let hash = obj
.class()
.mro_find_map(|cls| cls.slots.hash.load())
.unwrap(); // hash always exist
hash(&obj, self)
}
pub fn obj_len_opt(&self, obj: &PyObjectRef) -> Option<PyResult<usize>> {
self.get_method(obj.clone(), "__len__").map(|len| {
let len = self.invoke(&len?, ())?;
let len = len
.payload_if_subclass::<PyInt>(self)
.ok_or_else(|| {
self.new_type_error(format!(
"'{}' object cannot be interpreted as an integer",
len.class().name
))
})?
.borrow_value();
if len.is_negative() {
return Err(self.new_value_error("__len__() should return >= 0".to_owned()));
}
let len = len.to_isize().ok_or_else(|| {
self.new_overflow_error("cannot fit 'int' into an index-sized integer".to_owned())
})?;
Ok(len as usize)
})
}
pub fn obj_len(&self, obj: &PyObjectRef) -> PyResult<usize> {
self.obj_len_opt(obj).unwrap_or_else(|| {
Err(self.new_type_error(format!(
"object of type '{}' has no len()",
obj.class().name
)))
})
}
// https://docs.python.org/3/reference/expressions.html#membership-test-operations
fn _membership_iter_search(&self, haystack: PyObjectRef, needle: PyObjectRef) -> PyResult {
let iter = iterator::get_iter(self, haystack)?;
loop {
if let Some(element) = iterator::get_next_object(self, &iter)? {
if self.bool_eq(&needle, &element)? {
return Ok(self.ctx.new_bool(true));
} else {
continue;
}
} else {
return Ok(self.ctx.new_bool(false));
}
}
}
pub fn _membership(&self, haystack: PyObjectRef, needle: PyObjectRef) -> PyResult {
if let Some(method_or_err) = self.get_method(haystack.clone(), "__contains__") {
let method = method_or_err?;
self.invoke(&method, vec![needle])
} else {
self._membership_iter_search(haystack, needle)
}
}
pub fn push_exception(&self, exc: PyBaseExceptionRef) {
self.exceptions.borrow_mut().push(exc)
}
pub fn pop_exception(&self) -> Option<PyBaseExceptionRef> {
self.exceptions.borrow_mut().pop()
}
pub fn current_exception(&self) -> Option<PyBaseExceptionRef> {
self.exceptions.borrow().last().cloned()
}
pub fn bool_eq(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult<bool> {
self.bool_cmp(a, b, PyComparisonOp::Eq)
}
pub fn identical_or_equal(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult<bool> {
if a.is(b) {
Ok(true)
} else {
self.bool_eq(a, b)
}
}
pub fn bool_seq_lt(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult<Option<bool>> {
let value = if self.bool_cmp(a, b, PyComparisonOp::Lt)? {
Some(true)
} else if !self.bool_eq(a, b)? {
Some(false)
} else {
None
};
Ok(value)
}
pub fn bool_seq_gt(&self, a: &PyObjectRef, b: &PyObjectRef) -> PyResult<Option<bool>> {
let value = if self.bool_cmp(a, b, PyComparisonOp::Gt)? {
Some(true)
} else if !self.bool_eq(a, b)? {
Some(false)
} else {
None
};
Ok(value)
}
pub fn map_codeobj(&self, code: bytecode::CodeObject) -> code::CodeObject {
code.map_bag(&code::PyObjBag(self))
}
pub fn intern_string<S: Internable>(&self, s: S) -> PyStrRef {
let (s, ()) = self
.ctx
.string_cache
.setdefault_entry(self, s, || ())
.expect("string_cache lookup should never error");
s.downcast()
.expect("only strings should be in string_cache")
}
#[doc(hidden)]
pub fn __module_set_attr(
&self,
module: &PyObjectRef,
attr_name: impl TryIntoRef<PyStr>,
attr_value: impl Into<PyObjectRef>,
) -> PyResult<()> {
let val = attr_value.into();
object::setattr(module.clone(), attr_name.try_into_ref(self)?, val, self)
}
}
mod sealed {
use super::*;
pub trait SealedInternable {}
impl SealedInternable for String {}
impl SealedInternable for &str {}
impl SealedInternable for PyRefExact<PyStr> {}
}
/// A sealed marker trait for `DictKey` types that always become an exact instance of `str`
pub trait Internable: sealed::SealedInternable + crate::dictdatatype::DictKey {}
impl Internable for String {}
impl Internable for &str {}
impl Internable for PyRefExact<PyStr> {}
pub struct ReprGuard<'vm> {
vm: &'vm VirtualMachine,
id: usize,
}
/// A guard to protect repr methods from recursion into itself,
impl<'vm> ReprGuard<'vm> {
/// Returns None if the guard against 'obj' is still held otherwise returns the guard. The guard
/// which is released if dropped.
pub fn enter(vm: &'vm VirtualMachine, obj: &PyObjectRef) -> Option<Self> {
let mut guards = vm.repr_guards.borrow_mut();
// Should this be a flag on the obj itself? putting it in a global variable for now until it
// decided the form of the PyObject. https://github.com/RustPython/RustPython/issues/371
let id = obj.get_id();
if guards.contains(&id) {
return None;
}
guards.insert(id);
Some(ReprGuard { vm, id })
}
}
impl<'vm> Drop for ReprGuard<'vm> {
fn drop(&mut self) {
self.vm.repr_guards.borrow_mut().remove(&self.id);
}
}
pub struct Interpreter {
vm: VirtualMachine,
}
impl Interpreter {
pub fn new(settings: PySettings, init: InitParameter) -> Self {
Self::new_with_init(settings, |_| init)
}
pub fn new_with_init<F>(settings: PySettings, init: F) -> Self
where
F: FnOnce(&mut VirtualMachine) -> InitParameter,
{
let mut vm = VirtualMachine::new(settings);
let init = init(&mut vm);
vm.initialize(init);
Self { vm }
}
pub fn enter<F, R>(&self, f: F) -> R
where
F: FnOnce(&VirtualMachine) -> R,
{
thread::enter_vm(&self.vm, || f(&self.vm))
}
// TODO: interpreter shutdown
// pub fn run<F>(self, f: F)
// where
// F: FnOnce(&VirtualMachine),
// {
// self.enter(f);
// self.shutdown();
// }
// pub fn shutdown(self) {}
}
impl Default for Interpreter {
fn default() -> Self {
Self::new(PySettings::default(), InitParameter::External)
}
}
#[must_use = "PyThread does nothing unless you move it to another thread and call .run()"]
#[cfg(feature = "threading")]
pub struct PyThread {
thread_vm: VirtualMachine,
}
#[cfg(feature = "threading")]
impl PyThread {
/// Create a `FnOnce()` that can easily be passed to a function like [`std::thread::Builder::spawn`]
///
/// # Note
///
/// If you return a `PyObjectRef` (or a type that contains one) from `F`, and don't `join()`
/// on the thread this `FnOnce` runs in, there is a possibility that that thread will panic
/// as `PyObjectRef`'s `Drop` implementation tries to run the `__del__` destructor of a
/// Python object but finds that it's not in the context of any vm.
pub fn make_spawn_func<F, R>(self, f: F) -> impl FnOnce() -> R
where
F: FnOnce(&VirtualMachine) -> R,
{
move || self.run(f)
}
/// Run a function in this thread context
///
/// # Note
///
/// If you return a `PyObjectRef` (or a type that contains one) from `F`, and don't return the object
/// to the parent thread and then `join()` on the `JoinHandle` (or similar), there is a possibility that
/// the current thread will panic as `PyObjectRef`'s `Drop` implementation tries to run the `__del__`
/// destructor of a python object but finds that it's not in the context of any vm.
pub fn run<F, R>(self, f: F) -> R
where
F: FnOnce(&VirtualMachine) -> R,
{
let vm = &self.thread_vm;
thread::enter_vm(vm, || f(vm))
}
}
#[cfg(test)]
mod tests {
use super::Interpreter;
use crate::builtins::{int, pystr};
use num_bigint::ToBigInt;
#[test]
fn test_add_py_integers() {
Interpreter::default().enter(|vm| {
let a = vm.ctx.new_int(33_i32);
let b = vm.ctx.new_int(12_i32);
let res = vm._add(&a, &b).unwrap();
let value = int::get_value(&res);
assert_eq!(*value, 45_i32.to_bigint().unwrap());
})
}
#[test]
fn test_multiply_str() {
Interpreter::default().enter(|vm| {
let a = vm.ctx.new_str(String::from("Hello "));
let b = vm.ctx.new_int(4_i32);
let res = vm._mul(&a, &b).unwrap();
let value = pystr::borrow_value(&res);
assert_eq!(value, String::from("Hello Hello Hello Hello "))
})
}
}