mirror of https://github.com/boa-dev/boa.git
Browse Source
* Implement draft of module execution * Fix recursion bug * Re-enable JsObject's debug printing * Modify API and document some methods * Add missing documentation * Add newline to module scripts * npx prettier * Apply reviews * Add reference to parent struct on source module * Document more steps on the example * cargo clippy * Revert `BoaGc` changes * Lower `GcRefCell` to `Inner` of `SourceTextModule` * Replace weak ref to module with strong ref * Apply review * Clarify reasoning of manual `Trace` impl * Apply review pt. 2 * Revert gc changespull/2942/head
José Julián Espina
1 year ago
committed by
GitHub
37 changed files with 4239 additions and 264 deletions
@ -0,0 +1,120 @@
|
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use std::cell::Cell; |
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|
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use boa_ast::expression::Identifier; |
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use boa_gc::{Finalize, GcRefCell, Trace}; |
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|
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use crate::{module::Module, JsValue}; |
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|
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/// Type of accessor used to access an indirect binding.
|
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#[derive(Debug, Clone, Copy)] |
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enum BindingAccessor { |
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Identifier(Identifier), |
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Index(usize), |
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} |
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|
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/// An indirect reference to a binding inside an environment.
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#[derive(Clone, Debug, Trace, Finalize)] |
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struct IndirectBinding { |
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module: Module, |
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#[unsafe_ignore_trace] |
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accessor: Cell<BindingAccessor>, |
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} |
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|
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/// The type of binding a [`ModuleEnvironment`] can contain.
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#[derive(Clone, Debug, Trace, Finalize)] |
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enum BindingType { |
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Direct(Option<JsValue>), |
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Indirect(IndirectBinding), |
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} |
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|
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/// A [**Module Environment Record**][spec].
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///
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/// Module environments allow referencing bindings inside other environments, in addition
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/// to the usual declarative environment functionality.
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///
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///
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/// [spec]: https://tc39.es/ecma262/#sec-module-environment-records
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#[derive(Debug, Trace, Finalize)] |
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pub(crate) struct ModuleEnvironment { |
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bindings: GcRefCell<Vec<BindingType>>, |
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} |
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|
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impl ModuleEnvironment { |
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/// Creates a new `LexicalEnvironment`.
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pub(crate) fn new(bindings: usize) -> Self { |
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Self { |
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bindings: GcRefCell::new(vec![BindingType::Direct(None); bindings]), |
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} |
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} |
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|
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/// Get the binding value from the environment by it's index.
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///
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/// # Panics
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///
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/// Panics if the binding value is out of range or not initialized.
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#[track_caller] |
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pub(crate) fn get(&self, index: usize) -> Option<JsValue> { |
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let bindings = self.bindings.borrow(); |
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|
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match &bindings[index] { |
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BindingType::Direct(v) => v.clone(), |
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BindingType::Indirect(IndirectBinding { module, accessor }) => { |
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let env = module.environment()?; |
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|
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match accessor.get() { |
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BindingAccessor::Identifier(name) => { |
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let index = env |
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.compile_env() |
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.borrow() |
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.get_binding(name) |
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.expect("linking must ensure the binding exists"); |
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|
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let value = env.get(index.binding_index)?; |
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accessor.set(BindingAccessor::Index(index.binding_index)); |
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|
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Some(value) |
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} |
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BindingAccessor::Index(index) => env.get(index), |
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} |
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} |
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} |
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} |
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|
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/// Sets the binding value from the environment by index.
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///
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/// # Panics
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///
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/// Panics if the binding value is out of range.
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#[track_caller] |
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pub(crate) fn set(&self, index: usize, value: JsValue) { |
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let mut bindings = self.bindings.borrow_mut(); |
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|
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match &mut bindings[index] { |
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BindingType::Direct(v) => *v = Some(value), |
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BindingType::Indirect(_) => { |
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panic!("cannot modify indirect references to other environments") |
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} |
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} |
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} |
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|
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/// Creates an indirect binding reference to another environment binding.
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///
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/// # Panics
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///
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/// Panics if the binding value is out of range.
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#[track_caller] |
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pub(crate) fn set_indirect( |
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&self, |
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index: usize, |
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target_module: Module, |
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target_binding: Identifier, |
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) { |
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let mut bindings = self.bindings.borrow_mut(); |
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|
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bindings[index] = BindingType::Indirect(IndirectBinding { |
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module: target_module, |
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accessor: Cell::new(BindingAccessor::Identifier(target_binding)), |
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}); |
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} |
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} |
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@ -0,0 +1,737 @@
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//! Boa's implementation of the ECMAScript's module system.
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//!
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//! This module contains the [`Module`] type, which represents an [**Abstract Module Record**][module],
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//! a [`ModuleLoader`] trait for custom module loader implementations, and [`SimpleModuleLoader`],
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//! the default `ModuleLoader` for [`Context`] which can be used for most simple usecases.
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//!
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//! Every module roughly follows the same lifecycle:
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//! - Parse using [`Module::parse`].
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//! - Load all its dependencies using [`Module::load`].
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//! - Link its dependencies together using [`Module::link`].
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//! - Evaluate the module and its dependencies using [`Module::evaluate`].
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//!
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//! The [`ModuleLoader`] trait allows customizing the "load" step on the lifecycle
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//! of a module, which allows doing things like fetching modules from urls, having multiple
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//! "modpaths" from where to import modules, or using Rust futures to avoid blocking the main thread
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//! on loads.
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//!
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//! More information:
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//! - [ECMAScript reference][spec]
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//!
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//! [spec]: https://tc39.es/ecma262/#sec-modules
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//! [module]: https://tc39.es/ecma262/#sec-abstract-module-records
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|
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mod source; |
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use source::SourceTextModule; |
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|
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use std::cell::{Cell, RefCell}; |
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use std::hash::Hash; |
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use std::io::Read; |
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use std::path::{Path, PathBuf}; |
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use std::rc::Rc; |
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use std::{collections::HashSet, hash::BuildHasherDefault}; |
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|
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use indexmap::IndexMap; |
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use rustc_hash::{FxHashMap, FxHashSet, FxHasher}; |
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|
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use boa_ast::expression::Identifier; |
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use boa_gc::{Finalize, Gc, GcRefCell, Trace}; |
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use boa_interner::Sym; |
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use boa_parser::{Parser, Source}; |
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use boa_profiler::Profiler; |
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|
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use crate::object::FunctionObjectBuilder; |
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use crate::{ |
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builtins::promise::{PromiseCapability, PromiseState}, |
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environments::DeclarativeEnvironment, |
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object::{JsObject, JsPromise, ObjectData}, |
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realm::Realm, |
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Context, JsError, JsResult, JsString, JsValue, |
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}; |
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use crate::{js_string, JsNativeError, NativeFunction}; |
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/// The referrer from which a load request of a module originates.
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#[derive(Debug)] |
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pub enum Referrer { |
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/// A [**Source Text Module Record**](https://tc39.es/ecma262/#sec-source-text-module-records).
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Module(Module), |
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/// A [**Realm**](https://tc39.es/ecma262/#sec-code-realms).
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Realm(Realm), // TODO: script
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} |
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/// Module loading related host hooks.
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///
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/// This trait allows to customize the behaviour of the engine on module load requests and
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/// `import.meta` requests.
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pub trait ModuleLoader { |
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/// Host hook [`HostLoadImportedModule ( referrer, specifier, hostDefined, payload )`][spec].
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///
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/// This hook allows to customize the module loading functionality of the engine. Technically,
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/// this should call the [`FinishLoadingImportedModule`][finish] operation, but this simpler API just provides
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/// a closure that replaces `FinishLoadingImportedModule`.
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///
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/// # Requirements
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///
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/// - The host environment must perform `FinishLoadingImportedModule(referrer, specifier, payload, result)`,
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/// where result is either a normal completion containing the loaded Module Record or a throw
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/// completion, either synchronously or asynchronously. This is equivalent to calling the `finish_load`
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/// callback.
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/// - If this operation is called multiple times with the same `(referrer, specifier)` pair and
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/// it performs FinishLoadingImportedModule(referrer, specifier, payload, result) where result
|
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/// is a normal completion, then it must perform
|
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/// `FinishLoadingImportedModule(referrer, specifier, payload, result)` with the same result each
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/// time.
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/// - The operation must treat payload as an opaque value to be passed through to
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/// `FinishLoadingImportedModule`. (can be ignored)
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///
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/// [spec]: https://tc39.es/ecma262/#sec-HostLoadImportedModule
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/// [finish]: https://tc39.es/ecma262/#sec-FinishLoadingImportedModule
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#[allow(clippy::type_complexity)] |
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fn load_imported_module( |
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&self, |
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referrer: Referrer, |
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specifier: JsString, |
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finish_load: Box<dyn FnOnce(JsResult<Module>, &mut Context<'_>)>, |
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context: &mut Context<'_>, |
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); |
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|
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/// Host hooks [`HostGetImportMetaProperties ( moduleRecord )`][meta] and
|
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/// [`HostFinalizeImportMeta ( importMeta, moduleRecord )`][final].
|
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///
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/// This unifies both APIs into a single hook that can be overriden on both cases.
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/// The most common usage is to add properties to `import_meta` and return, but this also
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/// allows modifying the import meta object in more exotic ways before exposing it to ECMAScript
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/// code.
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///
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/// The default implementation of `HostGetImportMetaProperties` is to return a new empty List.
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///
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/// [meta]: https://tc39.es/ecma262/#sec-hostgetimportmetaproperties
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/// [final]: https://tc39.es/ecma262/#sec-hostfinalizeimportmeta
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fn init_import_meta( |
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&self, |
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_import_meta: JsObject, |
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_module: Module, |
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_context: &mut Context<'_>, |
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) { |
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} |
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} |
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|
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/// A simple module loader that loads modules relative to a root path.
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#[derive(Debug)] |
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pub struct SimpleModuleLoader { |
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root: PathBuf, |
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module_map: GcRefCell<FxHashMap<PathBuf, Module>>, |
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} |
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|
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impl SimpleModuleLoader { |
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/// Creates a new `SimpleModuleLoader` from a root module path.
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pub fn new<P: AsRef<Path>>(root: P) -> JsResult<Self> { |
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let root = root.as_ref(); |
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let absolute = root.canonicalize().map_err(|e| { |
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JsNativeError::typ() |
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.with_message(format!("could not set module root `{}`", root.display())) |
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.with_cause(JsError::from_opaque(js_string!(e.to_string()).into())) |
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})?; |
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Ok(Self { |
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root: absolute, |
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module_map: GcRefCell::default(), |
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}) |
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} |
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|
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/// Inserts a new module onto the module map.
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#[inline] |
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pub fn insert(&self, path: PathBuf, module: Module) { |
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self.module_map.borrow_mut().insert(path, module); |
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} |
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|
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/// Gets a module from its original path.
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#[inline] |
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pub fn get(&self, path: &Path) -> Option<Module> { |
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self.module_map.borrow().get(path).cloned() |
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} |
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} |
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|
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impl ModuleLoader for SimpleModuleLoader { |
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fn load_imported_module( |
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&self, |
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_referrer: Referrer, |
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specifier: JsString, |
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finish_load: Box<dyn FnOnce(JsResult<Module>, &mut Context<'_>)>, |
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context: &mut Context<'_>, |
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) { |
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let result = (|| { |
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let path = specifier |
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.to_std_string() |
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.map_err(|err| JsNativeError::typ().with_message(err.to_string()))?; |
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let short_path = Path::new(&path); |
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let path = self.root.join(short_path); |
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let path = path.canonicalize().map_err(|err| { |
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JsNativeError::typ() |
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.with_message(format!( |
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"could not canonicalize path `{}`", |
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short_path.display() |
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)) |
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.with_cause(JsError::from_opaque(js_string!(err.to_string()).into())) |
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})?; |
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if let Some(module) = self.get(&path) { |
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return Ok(module); |
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} |
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let source = Source::from_filepath(&path).map_err(|err| { |
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JsNativeError::typ() |
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.with_message(format!("could not open file `{}`", short_path.display())) |
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.with_cause(JsError::from_opaque(js_string!(err.to_string()).into())) |
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})?; |
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let module = Module::parse(source, None, context).map_err(|err| { |
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JsNativeError::error() |
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.with_message(format!("could not parse module `{}`", short_path.display())) |
||||
.with_cause(err) |
||||
})?; |
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self.insert(path, module.clone()); |
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Ok(module) |
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})(); |
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|
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finish_load(result, context); |
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} |
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} |
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|
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/// ECMAScript's [**Abstract module record**][spec].
|
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///
|
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/// [spec]: https://tc39.es/ecma262/#sec-abstract-module-records
|
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#[derive(Clone, Trace, Finalize)] |
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pub struct Module { |
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inner: Gc<Inner>, |
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} |
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|
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impl std::fmt::Debug for Module { |
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fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { |
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f.debug_struct("Module") |
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.field("realm", &self.inner.realm.addr()) |
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.field("environment", &self.inner.environment) |
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.field("namespace", &self.inner.namespace) |
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.field("kind", &self.inner.kind) |
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.field("host_defined", &self.inner.host_defined) |
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.finish() |
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} |
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} |
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|
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#[derive(Trace, Finalize)] |
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struct Inner { |
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realm: Realm, |
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environment: GcRefCell<Option<Gc<DeclarativeEnvironment>>>, |
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namespace: GcRefCell<Option<JsObject>>, |
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kind: ModuleKind, |
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host_defined: (), |
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} |
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|
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/// The kind of a [`Module`].
|
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#[derive(Debug, Trace, Finalize)] |
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pub(crate) enum ModuleKind { |
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/// A [**Source Text Module Record**](https://tc39.es/ecma262/#sec-source-text-module-records)
|
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SourceText(SourceTextModule), |
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/// A [**Synthetic Module Record**](https://tc39.es/proposal-json-modules/#sec-synthetic-module-records)
|
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#[allow(unused)] |
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Synthetic, |
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} |
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|
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/// Return value of the [`Module::resolve_export`] operation.
|
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///
|
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/// Indicates how to access a specific export in a module.
|
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#[derive(Debug, Clone)] |
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pub(crate) struct ResolvedBinding { |
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module: Module, |
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binding_name: BindingName, |
||||
} |
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|
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/// The local name of the resolved binding within its containing module.
|
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///
|
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/// Note that a resolved binding can resolve to a single binding inside a module (`export var a = 1"`)
|
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/// or to a whole module namespace (`export * as ns from "mod.js"`).
|
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#[derive(Debug, Clone, Copy)] |
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pub(crate) enum BindingName { |
||||
/// A local binding.
|
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Name(Identifier), |
||||
/// The whole namespace of the containing module.
|
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Namespace, |
||||
} |
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|
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impl ResolvedBinding { |
||||
/// Gets the module from which the export resolved.
|
||||
pub(crate) const fn module(&self) -> &Module { |
||||
&self.module |
||||
} |
||||
|
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/// Gets the binding associated with the resolved export.
|
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pub(crate) const fn binding_name(&self) -> BindingName { |
||||
self.binding_name |
||||
} |
||||
} |
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|
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#[derive(Debug, Clone)] |
||||
struct GraphLoadingState { |
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capability: PromiseCapability, |
||||
loading: Cell<bool>, |
||||
pending_modules: Cell<usize>, |
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visited: RefCell<HashSet<SourceTextModule>>, |
||||
} |
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|
||||
#[derive(Debug, Clone, Copy)] |
||||
pub(crate) enum ResolveExportError { |
||||
NotFound, |
||||
Ambiguous, |
||||
} |
||||
|
||||
impl Module { |
||||
/// Abstract operation [`ParseModule ( sourceText, realm, hostDefined )`][spec].
|
||||
///
|
||||
/// Parses the provided `src` as an ECMAScript module, returning an error if parsing fails.
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-parsemodule
|
||||
#[inline] |
||||
pub fn parse<R: Read>( |
||||
src: Source<'_, R>, |
||||
realm: Option<Realm>, |
||||
context: &mut Context<'_>, |
||||
) -> JsResult<Module> { |
||||
let _timer = Profiler::global().start_event("Module parsing", "Main"); |
||||
let mut parser = Parser::new(src); |
||||
parser.set_identifier(context.next_parser_identifier()); |
||||
let module = parser.parse_module(context.interner_mut())?; |
||||
|
||||
let src = SourceTextModule::new(module); |
||||
|
||||
let module = Module { |
||||
inner: Gc::new(Inner { |
||||
realm: realm.unwrap_or_else(|| context.realm().clone()), |
||||
environment: GcRefCell::default(), |
||||
namespace: GcRefCell::default(), |
||||
kind: ModuleKind::SourceText(src.clone()), |
||||
host_defined: (), |
||||
}), |
||||
}; |
||||
|
||||
src.set_parent(module.clone()); |
||||
|
||||
Ok(module) |
||||
} |
||||
|
||||
/// Gets the realm of this `Module`.
|
||||
#[inline] |
||||
pub fn realm(&self) -> &Realm { |
||||
&self.inner.realm |
||||
} |
||||
|
||||
/// Gets the kind of this `Module`.
|
||||
pub(crate) fn kind(&self) -> &ModuleKind { |
||||
&self.inner.kind |
||||
} |
||||
|
||||
/// Gets the environment of this `Module`.
|
||||
pub(crate) fn environment(&self) -> Option<Gc<DeclarativeEnvironment>> { |
||||
self.inner.environment.borrow().clone() |
||||
} |
||||
|
||||
/// Abstract method [`LoadRequestedModules ( [ hostDefined ] )`][spec].
|
||||
///
|
||||
/// Prepares the module for linking by loading all its module dependencies. Returns a `JsPromise`
|
||||
/// that will resolve when the loading process either completes or fails.
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#table-abstract-methods-of-module-records
|
||||
#[allow(clippy::missing_panics_doc)] |
||||
#[inline] |
||||
pub fn load(&self, context: &mut Context<'_>) -> JsPromise { |
||||
match self.kind() { |
||||
ModuleKind::SourceText(_) => { |
||||
// Concrete method [`LoadRequestedModules ( [ hostDefined ] )`][spec].
|
||||
//
|
||||
// [spec]: https://tc39.es/ecma262/#sec-LoadRequestedModules
|
||||
// TODO: 1. If hostDefined is not present, let hostDefined be empty.
|
||||
|
||||
// 2. Let pc be ! NewPromiseCapability(%Promise%).
|
||||
let pc = PromiseCapability::new( |
||||
&context.intrinsics().constructors().promise().constructor(), |
||||
context, |
||||
) |
||||
.expect( |
||||
"capability creation must always succeed when using the `%Promise%` intrinsic", |
||||
); |
||||
|
||||
// 4. Perform InnerModuleLoading(state, module).
|
||||
self.inner_load( |
||||
// 3. Let state be the GraphLoadingState Record {
|
||||
// [[IsLoading]]: true, [[PendingModulesCount]]: 1, [[Visited]]: « »,
|
||||
// [[PromiseCapability]]: pc, [[HostDefined]]: hostDefined
|
||||
// }.
|
||||
&Rc::new(GraphLoadingState { |
||||
capability: pc.clone(), |
||||
loading: Cell::new(true), |
||||
pending_modules: Cell::new(1), |
||||
visited: RefCell::default(), |
||||
}), |
||||
context, |
||||
); |
||||
|
||||
// 5. Return pc.[[Promise]].
|
||||
JsPromise::from_object(pc.promise().clone()) |
||||
.expect("promise created from the %Promise% intrinsic is always native") |
||||
} |
||||
ModuleKind::Synthetic => todo!("synthetic.load()"), |
||||
} |
||||
} |
||||
|
||||
/// Abstract operation [`InnerModuleLoading`][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-InnerModuleLoading
|
||||
fn inner_load(&self, state: &Rc<GraphLoadingState>, context: &mut Context<'_>) { |
||||
// 1. Assert: state.[[IsLoading]] is true.
|
||||
assert!(state.loading.get()); |
||||
|
||||
if let ModuleKind::SourceText(src) = self.kind() { |
||||
// continues on `inner_load
|
||||
src.inner_load(state, context); |
||||
if !state.loading.get() { |
||||
return; |
||||
} |
||||
} |
||||
|
||||
// 3. Assert: state.[[PendingModulesCount]] ≥ 1.
|
||||
assert!(state.pending_modules.get() >= 1); |
||||
|
||||
// 4. Set state.[[PendingModulesCount]] to state.[[PendingModulesCount]] - 1.
|
||||
state.pending_modules.set(state.pending_modules.get() - 1); |
||||
// 5. If state.[[PendingModulesCount]] = 0, then
|
||||
|
||||
if state.pending_modules.get() == 0 { |
||||
// a. Set state.[[IsLoading]] to false.
|
||||
state.loading.set(false); |
||||
// b. For each Cyclic Module Record loaded of state.[[Visited]], do
|
||||
// i. If loaded.[[Status]] is new, set loaded.[[Status]] to unlinked.
|
||||
// By default, all modules start on `unlinked`.
|
||||
|
||||
// c. Perform ! Call(state.[[PromiseCapability]].[[Resolve]], undefined, « undefined »).
|
||||
state |
||||
.capability |
||||
.resolve() |
||||
.call(&JsValue::undefined(), &[], context) |
||||
.expect("marking a module as loaded should not fail"); |
||||
} |
||||
// 6. Return unused.
|
||||
} |
||||
|
||||
/// Abstract method [`GetExportedNames([exportStarSet])`][spec].
|
||||
///
|
||||
/// Returns a list of all the names exported from this module.
|
||||
///
|
||||
/// # Note
|
||||
///
|
||||
/// This must only be called if the [`JsPromise`] returned by [`Module::load`] has fulfilled.
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#table-abstract-methods-of-module-records
|
||||
fn get_exported_names(&self, export_star_set: &mut Vec<SourceTextModule>) -> FxHashSet<Sym> { |
||||
match self.kind() { |
||||
ModuleKind::SourceText(src) => src.get_exported_names(export_star_set), |
||||
ModuleKind::Synthetic => todo!("synthetic.get_exported_names()"), |
||||
} |
||||
} |
||||
|
||||
/// Abstract method [`ResolveExport(exportName [, resolveSet])`][spec].
|
||||
///
|
||||
/// Returns the corresponding local binding of a binding exported by this module.
|
||||
/// The spec requires that this operation must be idempotent; calling this multiple times
|
||||
/// with the same `export_name` and `resolve_set` should always return the same result.
|
||||
///
|
||||
/// # Note
|
||||
///
|
||||
/// This must only be called if the [`JsPromise`] returned by [`Module::load`] has fulfilled.
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#table-abstract-methods-of-module-records
|
||||
#[allow(clippy::mutable_key_type)] |
||||
pub(crate) fn resolve_export( |
||||
&self, |
||||
export_name: Sym, |
||||
resolve_set: &mut FxHashSet<(Module, Sym)>, |
||||
) -> Result<ResolvedBinding, ResolveExportError> { |
||||
match self.kind() { |
||||
ModuleKind::SourceText(src) => src.resolve_export(export_name, resolve_set), |
||||
ModuleKind::Synthetic => todo!("synthetic.resolve_export()"), |
||||
} |
||||
} |
||||
|
||||
/// Abstract method [`Link() `][spec].
|
||||
///
|
||||
/// Prepares this module for evaluation by resolving all its module dependencies and initializing
|
||||
/// its environment.
|
||||
///
|
||||
/// # Note
|
||||
///
|
||||
/// This must only be called if the [`JsPromise`] returned by [`Module::load`] has fulfilled.
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#table-abstract-methods-of-module-records
|
||||
#[allow(clippy::missing_panics_doc)] |
||||
#[inline] |
||||
pub fn link(&self, context: &mut Context<'_>) -> JsResult<()> { |
||||
match self.kind() { |
||||
ModuleKind::SourceText(src) => src.link(context), |
||||
ModuleKind::Synthetic => todo!("synthetic.link()"), |
||||
} |
||||
} |
||||
|
||||
/// Abstract operation [`InnerModuleLinking ( module, stack, index )`][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-InnerModuleLinking
|
||||
fn inner_link( |
||||
&self, |
||||
stack: &mut Vec<SourceTextModule>, |
||||
index: usize, |
||||
context: &mut Context<'_>, |
||||
) -> JsResult<usize> { |
||||
match self.kind() { |
||||
ModuleKind::SourceText(src) => src.inner_link(stack, index, context), |
||||
#[allow(unreachable_code)] |
||||
// If module is not a Cyclic Module Record, then
|
||||
ModuleKind::Synthetic => { |
||||
// a. Perform ? module.Link().
|
||||
todo!("synthetic.link()"); |
||||
// b. Return index.
|
||||
Ok(index) |
||||
} |
||||
} |
||||
} |
||||
|
||||
/// Abstract method [`Evaluate()`][spec].
|
||||
///
|
||||
/// Evaluates this module, returning a promise for the result of the evaluation of this module
|
||||
/// and its dependencies.
|
||||
/// If the promise is rejected, hosts are expected to handle the promise rejection and rethrow
|
||||
/// the evaluation error.
|
||||
///
|
||||
/// # Note
|
||||
///
|
||||
/// This must only be called if the [`Module::link`] method finished successfully.
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#table-abstract-methods-of-module-records
|
||||
#[allow(clippy::missing_panics_doc)] |
||||
#[inline] |
||||
pub fn evaluate(&self, context: &mut Context<'_>) -> JsPromise { |
||||
match self.kind() { |
||||
ModuleKind::SourceText(src) => src.evaluate(context), |
||||
ModuleKind::Synthetic => todo!("synthetic.evaluate()"), |
||||
} |
||||
} |
||||
|
||||
/// Abstract operation [`InnerModuleLinking ( module, stack, index )`][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-InnerModuleLinking
|
||||
fn inner_evaluate( |
||||
&self, |
||||
stack: &mut Vec<SourceTextModule>, |
||||
index: usize, |
||||
context: &mut Context<'_>, |
||||
) -> JsResult<usize> { |
||||
match self.kind() { |
||||
ModuleKind::SourceText(src) => src.inner_evaluate(stack, index, None, context), |
||||
// 1. If module is not a Cyclic Module Record, then
|
||||
#[allow(unused, clippy::diverging_sub_expression)] |
||||
ModuleKind::Synthetic => { |
||||
// a. Let promise be ! module.Evaluate().
|
||||
let promise: JsPromise = todo!("module.Evaluate()"); |
||||
let state = promise.state()?; |
||||
match state { |
||||
PromiseState::Pending => { |
||||
unreachable!("b. Assert: promise.[[PromiseState]] is not pending.") |
||||
} |
||||
// d. Return index.
|
||||
PromiseState::Fulfilled(_) => Ok(index), |
||||
// c. If promise.[[PromiseState]] is rejected, then
|
||||
// i. Return ThrowCompletion(promise.[[PromiseResult]]).
|
||||
PromiseState::Rejected(err) => Err(JsError::from_opaque(err)), |
||||
} |
||||
} |
||||
} |
||||
} |
||||
|
||||
/// Loads, links and evaluates this module, returning a promise that will resolve after the module
|
||||
/// finishes its lifecycle.
|
||||
///
|
||||
/// # Examples
|
||||
/// ```
|
||||
/// # use std::path::Path;
|
||||
/// # use boa_engine::{Context, Source, Module, JsValue};
|
||||
/// # use boa_engine::builtins::promise::PromiseState;
|
||||
/// # use boa_engine::module::{ModuleLoader, SimpleModuleLoader};
|
||||
/// let loader = &SimpleModuleLoader::new(Path::new(".")).unwrap();
|
||||
/// let dyn_loader: &dyn ModuleLoader = loader;
|
||||
/// let mut context = &mut Context::builder().module_loader(dyn_loader).build().unwrap();
|
||||
///
|
||||
/// let source = Source::from_bytes("1 + 3");
|
||||
///
|
||||
/// let module = Module::parse(source, None, context).unwrap();
|
||||
///
|
||||
/// loader.insert(Path::new("main.mjs").to_path_buf(), module.clone());
|
||||
///
|
||||
/// let promise = module.load_link_evaluate(context).unwrap();
|
||||
///
|
||||
/// context.run_jobs();
|
||||
///
|
||||
/// assert_eq!(promise.state().unwrap(), PromiseState::Fulfilled(JsValue::undefined()));
|
||||
/// ```
|
||||
#[allow(clippy::drop_copy)] |
||||
#[inline] |
||||
pub fn load_link_evaluate(&self, context: &mut Context<'_>) -> JsResult<JsPromise> { |
||||
let main_timer = Profiler::global().start_event("Module evaluation", "Main"); |
||||
|
||||
let promise = self |
||||
.load(context) |
||||
.then( |
||||
Some( |
||||
FunctionObjectBuilder::new( |
||||
context, |
||||
NativeFunction::from_copy_closure_with_captures( |
||||
|_, _, module, context| { |
||||
module.link(context)?; |
||||
Ok(JsValue::undefined()) |
||||
}, |
||||
self.clone(), |
||||
), |
||||
) |
||||
.build(), |
||||
), |
||||
None, |
||||
context, |
||||
)? |
||||
.then( |
||||
Some( |
||||
FunctionObjectBuilder::new( |
||||
context, |
||||
NativeFunction::from_copy_closure_with_captures( |
||||
|_, _, module, context| Ok(module.evaluate(context).into()), |
||||
self.clone(), |
||||
), |
||||
) |
||||
.build(), |
||||
), |
||||
None, |
||||
context, |
||||
)?; |
||||
|
||||
// The main_timer needs to be dropped before the Profiler is.
|
||||
drop(main_timer); |
||||
Profiler::global().drop(); |
||||
|
||||
Ok(promise) |
||||
} |
||||
|
||||
/// Abstract operation [`GetModuleNamespace ( module )`][spec].
|
||||
///
|
||||
/// Gets the [**Module Namespace Object**][ns] that represents this module's exports.
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-getmodulenamespace
|
||||
/// [ns]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects
|
||||
pub fn namespace(&self, context: &mut Context<'_>) -> JsObject { |
||||
// 1. Assert: If module is a Cyclic Module Record, then module.[[Status]] is not new or unlinked.
|
||||
// 2. Let namespace be module.[[Namespace]].
|
||||
// 3. If namespace is empty, then
|
||||
// 4. Return namespace.
|
||||
self.inner |
||||
.namespace |
||||
.borrow_mut() |
||||
.get_or_insert_with(|| { |
||||
// a. Let exportedNames be module.GetExportedNames().
|
||||
let exported_names = self.get_exported_names(&mut Vec::default()); |
||||
|
||||
// b. Let unambiguousNames be a new empty List.
|
||||
let unambiguous_names = exported_names |
||||
.into_iter() |
||||
// c. For each element name of exportedNames, do
|
||||
.filter_map(|name| { |
||||
// i. Let resolution be module.ResolveExport(name).
|
||||
// ii. If resolution is a ResolvedBinding Record, append name to unambiguousNames.
|
||||
self.resolve_export(name, &mut HashSet::default()) |
||||
.ok() |
||||
.map(|_| name) |
||||
}) |
||||
.collect(); |
||||
|
||||
// d. Set namespace to ModuleNamespaceCreate(module, unambiguousNames).
|
||||
ModuleNamespace::create(self.clone(), unambiguous_names, context) |
||||
}) |
||||
.clone() |
||||
} |
||||
} |
||||
|
||||
impl PartialEq for Module { |
||||
#[inline] |
||||
fn eq(&self, other: &Self) -> bool { |
||||
std::ptr::eq(self.inner.as_ref(), other.inner.as_ref()) |
||||
} |
||||
} |
||||
|
||||
impl Eq for Module {} |
||||
|
||||
impl Hash for Module { |
||||
#[inline] |
||||
fn hash<H: std::hash::Hasher>(&self, state: &mut H) { |
||||
std::ptr::hash(self.inner.as_ref(), state); |
||||
} |
||||
} |
||||
|
||||
/// Module namespace exotic object.
|
||||
///
|
||||
/// Exposes the bindings exported by a [`Module`] to be accessed from ECMAScript code.
|
||||
#[derive(Debug, Trace, Finalize)] |
||||
pub struct ModuleNamespace { |
||||
module: Module, |
||||
#[unsafe_ignore_trace] |
||||
exports: IndexMap<JsString, Sym, BuildHasherDefault<FxHasher>>, |
||||
} |
||||
|
||||
impl ModuleNamespace { |
||||
/// Abstract operation [`ModuleNamespaceCreate ( module, exports )`][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-modulenamespacecreate
|
||||
pub(crate) fn create(module: Module, names: Vec<Sym>, context: &mut Context<'_>) -> JsObject { |
||||
// 1. Assert: module.[[Namespace]] is empty.
|
||||
// ignored since this is ensured by `Module::namespace`.
|
||||
|
||||
// 6. Let sortedExports be a List whose elements are the elements of exports ordered as if an Array of the same values had been sorted using %Array.prototype.sort% using undefined as comparefn.
|
||||
let mut exports = names |
||||
.into_iter() |
||||
.map(|sym| { |
||||
( |
||||
context |
||||
.interner() |
||||
.resolve_expect(sym) |
||||
.into_common::<JsString>(false), |
||||
sym, |
||||
) |
||||
}) |
||||
.collect::<IndexMap<_, _, _>>(); |
||||
exports.sort_keys(); |
||||
|
||||
// 2. Let internalSlotsList be the internal slots listed in Table 32.
|
||||
// 3. Let M be MakeBasicObject(internalSlotsList).
|
||||
// 4. Set M's essential internal methods to the definitions specified in 10.4.6.
|
||||
// 5. Set M.[[Module]] to module.
|
||||
// 7. Set M.[[Exports]] to sortedExports.
|
||||
// 8. Create own properties of M corresponding to the definitions in 28.3.
|
||||
let namespace = context.intrinsics().templates().namespace().create( |
||||
ObjectData::module_namespace(ModuleNamespace { module, exports }), |
||||
vec![js_string!("Module").into()], |
||||
); |
||||
|
||||
// 9. Set module.[[Namespace]] to M.
|
||||
// Ignored because this is done by `Module::namespace`
|
||||
|
||||
// 10. Return M.
|
||||
namespace |
||||
} |
||||
|
||||
/// Gets the export names of the Module Namespace object.
|
||||
pub(crate) const fn exports(&self) -> &IndexMap<JsString, Sym, BuildHasherDefault<FxHasher>> { |
||||
&self.exports |
||||
} |
||||
|
||||
/// Gest the module associated with this Module Namespace object.
|
||||
pub(crate) const fn module(&self) -> &Module { |
||||
&self.module |
||||
} |
||||
} |
||||
File diff suppressed because it is too large
Load Diff
@ -0,0 +1,39 @@
|
||||
use crate::{ |
||||
object::{JsObject, JsPrototype}, |
||||
Context, JsResult, |
||||
}; |
||||
|
||||
use super::{InternalObjectMethods, ORDINARY_INTERNAL_METHODS}; |
||||
|
||||
/// Definitions of the internal object methods for [**Immutable Prototype Exotic Objects**][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-immutable-prototype-exotic-objects
|
||||
pub(crate) static IMMUTABLE_PROTOTYPE_EXOTIC_INTERNAL_METHODS: InternalObjectMethods = |
||||
InternalObjectMethods { |
||||
__set_prototype_of__: immutable_prototype_exotic_set_prototype_of, |
||||
..ORDINARY_INTERNAL_METHODS |
||||
}; |
||||
|
||||
/// [`[[SetPrototypeOf]] ( V )`][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-immutable-prototype-exotic-objects-setprototypeof-v
|
||||
#[allow(clippy::needless_pass_by_value)] |
||||
pub(crate) fn immutable_prototype_exotic_set_prototype_of( |
||||
obj: &JsObject, |
||||
val: JsPrototype, |
||||
context: &mut Context<'_>, |
||||
) -> JsResult<bool> { |
||||
// 1. Return ? SetImmutablePrototype(O, V).
|
||||
|
||||
// inlined since other implementations can just use `set_prototype_of` directly.
|
||||
|
||||
// SetImmutablePrototype ( O, V )
|
||||
// <https://tc39.es/ecma262/#sec-set-immutable-prototype>
|
||||
|
||||
// 1. Let current be ? O.[[GetPrototypeOf]]().
|
||||
let current = obj.__get_prototype_of__(context)?; |
||||
|
||||
// 2. If SameValue(V, current) is true, return true.
|
||||
// 3. Return false.
|
||||
Ok(val == current) |
||||
} |
||||
@ -0,0 +1,329 @@
|
||||
use std::collections::HashSet; |
||||
|
||||
use crate::{ |
||||
module::BindingName, |
||||
object::{JsObject, JsPrototype}, |
||||
property::{PropertyDescriptor, PropertyKey}, |
||||
Context, JsNativeError, JsResult, JsValue, |
||||
}; |
||||
|
||||
use super::{ |
||||
immutable_prototype, ordinary_define_own_property, ordinary_delete, ordinary_get, |
||||
ordinary_get_own_property, ordinary_has_property, ordinary_own_property_keys, |
||||
InternalObjectMethods, ORDINARY_INTERNAL_METHODS, |
||||
}; |
||||
|
||||
/// Definitions of the internal object methods for [**Module Namespace Exotic Objects**][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects
|
||||
pub(crate) static MODULE_NAMESPACE_EXOTIC_INTERNAL_METHODS: InternalObjectMethods = |
||||
InternalObjectMethods { |
||||
__get_prototype_of__: module_namespace_exotic_get_prototype_of, |
||||
__set_prototype_of__: module_namespace_exotic_set_prototype_of, |
||||
__is_extensible__: module_namespace_exotic_is_extensible, |
||||
__prevent_extensions__: module_namespace_exotic_prevent_extensions, |
||||
__get_own_property__: module_namespace_exotic_get_own_property, |
||||
__define_own_property__: module_namespace_exotic_define_own_property, |
||||
__has_property__: module_namespace_exotic_has_property, |
||||
__get__: module_namespace_exotic_get, |
||||
__set__: module_namespace_exotic_set, |
||||
__delete__: module_namespace_exotic_delete, |
||||
__own_property_keys__: module_namespace_exotic_own_property_keys, |
||||
..ORDINARY_INTERNAL_METHODS |
||||
}; |
||||
|
||||
/// [`[[GetPrototypeOf]] ( )`][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects-getprototypeof
|
||||
#[allow(clippy::unnecessary_wraps)] |
||||
fn module_namespace_exotic_get_prototype_of( |
||||
_: &JsObject, |
||||
_: &mut Context<'_>, |
||||
) -> JsResult<JsPrototype> { |
||||
// 1. Return null.
|
||||
Ok(None) |
||||
} |
||||
|
||||
/// [`[[SetPrototypeOf]] ( V )`][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects-setprototypeof-v
|
||||
#[allow(clippy::unnecessary_wraps)] |
||||
fn module_namespace_exotic_set_prototype_of( |
||||
obj: &JsObject, |
||||
val: JsPrototype, |
||||
context: &mut Context<'_>, |
||||
) -> JsResult<bool> { |
||||
// 1. Return ! SetImmutablePrototype(O, V).
|
||||
Ok( |
||||
immutable_prototype::immutable_prototype_exotic_set_prototype_of(obj, val, context) |
||||
.expect("this must not fail per the spec"), |
||||
) |
||||
} |
||||
|
||||
/// [`[[IsExtensible]] ( )`][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects-isextensible
|
||||
#[allow(clippy::unnecessary_wraps)] |
||||
fn module_namespace_exotic_is_extensible(_: &JsObject, _: &mut Context<'_>) -> JsResult<bool> { |
||||
// 1. Return false.
|
||||
Ok(false) |
||||
} |
||||
|
||||
/// [`[[PreventExtensions]] ( )`][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects-preventextensions
|
||||
#[allow(clippy::unnecessary_wraps)] |
||||
fn module_namespace_exotic_prevent_extensions(_: &JsObject, _: &mut Context<'_>) -> JsResult<bool> { |
||||
Ok(true) |
||||
} |
||||
|
||||
/// [`[[GetOwnProperty]] ( P )`][spec]
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects-getownproperty-p
|
||||
fn module_namespace_exotic_get_own_property( |
||||
obj: &JsObject, |
||||
key: &PropertyKey, |
||||
context: &mut Context<'_>, |
||||
) -> JsResult<Option<PropertyDescriptor>> { |
||||
// 1. If P is a Symbol, return OrdinaryGetOwnProperty(O, P).
|
||||
let key = match key { |
||||
PropertyKey::Symbol(_) => return ordinary_get_own_property(obj, key, context), |
||||
PropertyKey::Index(_) => return Ok(None), |
||||
PropertyKey::String(s) => s, |
||||
}; |
||||
|
||||
{ |
||||
let obj = obj.borrow(); |
||||
let obj = obj |
||||
.as_module_namespace() |
||||
.expect("internal method can only be called on module namespace objects"); |
||||
// 2. Let exports be O.[[Exports]].
|
||||
let exports = obj.exports(); |
||||
|
||||
// 3. If exports does not contain P, return undefined.
|
||||
if !exports.contains_key(key) { |
||||
return Ok(None); |
||||
} |
||||
} |
||||
|
||||
// 4. Let value be ? O.[[Get]](P, O).
|
||||
let value = obj.get(key.clone(), context)?; |
||||
|
||||
// 5. Return PropertyDescriptor { [[Value]]: value, [[Writable]]: true, [[Enumerable]]: true, [[Configurable]]: false }.
|
||||
Ok(Some( |
||||
PropertyDescriptor::builder() |
||||
.value(value) |
||||
.writable(true) |
||||
.enumerable(true) |
||||
.configurable(false) |
||||
.build(), |
||||
)) |
||||
} |
||||
|
||||
/// [`[[DefineOwnProperty]] ( P, Desc )`][spec]
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects-defineownproperty-p-desc
|
||||
fn module_namespace_exotic_define_own_property( |
||||
obj: &JsObject, |
||||
key: &PropertyKey, |
||||
desc: PropertyDescriptor, |
||||
context: &mut Context<'_>, |
||||
) -> JsResult<bool> { |
||||
// 1. If P is a Symbol, return ! OrdinaryDefineOwnProperty(O, P, Desc).
|
||||
if let PropertyKey::Symbol(_) = key { |
||||
return ordinary_define_own_property(obj, key, desc, context); |
||||
} |
||||
|
||||
// 2. Let current be ? O.[[GetOwnProperty]](P).
|
||||
let Some(current) = obj.__get_own_property__(key, context)? else { |
||||
// 3. If current is undefined, return false.
|
||||
return Ok(false); |
||||
}; |
||||
|
||||
// 4. If Desc has a [[Configurable]] field and Desc.[[Configurable]] is true, return false.
|
||||
// 5. If Desc has an [[Enumerable]] field and Desc.[[Enumerable]] is false, return false.
|
||||
// 6. If IsAccessorDescriptor(Desc) is true, return false.
|
||||
// 7. If Desc has a [[Writable]] field and Desc.[[Writable]] is false, return false.
|
||||
if desc.configurable() == Some(true) |
||||
|| desc.enumerable() == Some(false) |
||||
|| desc.is_accessor_descriptor() |
||||
|| desc.writable() == Some(false) |
||||
{ |
||||
return Ok(false); |
||||
} |
||||
|
||||
// 8. If Desc has a [[Value]] field, return SameValue(Desc.[[Value]], current.[[Value]]).
|
||||
// 9. Return true.
|
||||
Ok(desc.value().map_or(true, |v| v == current.expect_value())) |
||||
} |
||||
|
||||
/// [`[[HasProperty]] ( P )`][spec]
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects-hasproperty-p
|
||||
fn module_namespace_exotic_has_property( |
||||
obj: &JsObject, |
||||
key: &PropertyKey, |
||||
context: &mut Context<'_>, |
||||
) -> JsResult<bool> { |
||||
// 1. If P is a Symbol, return ! OrdinaryHasProperty(O, P).
|
||||
let key = match key { |
||||
PropertyKey::Symbol(_) => return ordinary_has_property(obj, key, context), |
||||
PropertyKey::Index(_) => return Ok(false), |
||||
PropertyKey::String(s) => s, |
||||
}; |
||||
|
||||
let obj = obj.borrow(); |
||||
let obj = obj |
||||
.as_module_namespace() |
||||
.expect("internal method can only be called on module namespace objects"); |
||||
|
||||
// 2. Let exports be O.[[Exports]].
|
||||
let exports = obj.exports(); |
||||
|
||||
// 3. If exports contains P, return true.
|
||||
// 4. Return false.
|
||||
Ok(exports.contains_key(key)) |
||||
} |
||||
|
||||
/// [`[[Get]] ( P, Receiver )`][spec]
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects-get-p-receiver
|
||||
fn module_namespace_exotic_get( |
||||
obj: &JsObject, |
||||
key: &PropertyKey, |
||||
receiver: JsValue, |
||||
context: &mut Context<'_>, |
||||
) -> JsResult<JsValue> { |
||||
// 1. If P is a Symbol, then
|
||||
// a. Return ! OrdinaryGet(O, P, Receiver).
|
||||
let key = match key { |
||||
PropertyKey::Symbol(_) => return ordinary_get(obj, key, receiver, context), |
||||
PropertyKey::Index(_) => return Ok(JsValue::undefined()), |
||||
PropertyKey::String(s) => s, |
||||
}; |
||||
|
||||
let obj = obj.borrow(); |
||||
let obj = obj |
||||
.as_module_namespace() |
||||
.expect("internal method can only be called on module namespace objects"); |
||||
|
||||
// 2. Let exports be O.[[Exports]].
|
||||
let exports = obj.exports(); |
||||
// 3. If exports does not contain P, return undefined.
|
||||
let Some(export_name) = exports.get(key).copied() else { |
||||
return Ok(JsValue::undefined()); |
||||
}; |
||||
|
||||
// 4. Let m be O.[[Module]].
|
||||
let m = obj.module(); |
||||
|
||||
// 5. Let binding be m.ResolveExport(P).
|
||||
let binding = m |
||||
.resolve_export(export_name, &mut HashSet::default()) |
||||
.expect("6. Assert: binding is a ResolvedBinding Record."); |
||||
|
||||
// 7. Let targetModule be binding.[[Module]].
|
||||
// 8. Assert: targetModule is not undefined.
|
||||
let target_module = binding.module(); |
||||
|
||||
// TODO: cache binding resolution instead of doing the whole process on every access.
|
||||
if let BindingName::Name(name) = binding.binding_name() { |
||||
// 10. Let targetEnv be targetModule.[[Environment]].
|
||||
let Some(env) = target_module.environment() else { |
||||
// 11. If targetEnv is empty, throw a ReferenceError exception.
|
||||
let import = context.interner().resolve_expect(export_name); |
||||
return Err(JsNativeError::reference().with_message( |
||||
format!("cannot get import `{import}` from an uninitialized module") |
||||
).into()); |
||||
}; |
||||
|
||||
let locator = env |
||||
.compile_env() |
||||
.borrow() |
||||
.get_binding(name) |
||||
.expect("checked before that the name was reachable"); |
||||
|
||||
// 12. Return ? targetEnv.GetBindingValue(binding.[[BindingName]], true).
|
||||
env.get(locator.binding_index()).ok_or_else(|| { |
||||
let import = context.interner().resolve_expect(export_name); |
||||
|
||||
JsNativeError::reference() |
||||
.with_message(format!("cannot get uninitialized import `{import}`")) |
||||
.into() |
||||
}) |
||||
} else { |
||||
// 9. If binding.[[BindingName]] is namespace, then
|
||||
// a. Return GetModuleNamespace(targetModule).
|
||||
Ok(target_module.namespace(context).into()) |
||||
} |
||||
} |
||||
|
||||
/// [`[[Set]] ( P, V, Receiver )`][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects-set-p-v-receiver
|
||||
#[allow(clippy::needless_pass_by_value, clippy::unnecessary_wraps)] |
||||
fn module_namespace_exotic_set( |
||||
_obj: &JsObject, |
||||
_key: PropertyKey, |
||||
_value: JsValue, |
||||
_receiver: JsValue, |
||||
_context: &mut Context<'_>, |
||||
) -> JsResult<bool> { |
||||
// 1. Return false.
|
||||
Ok(false) |
||||
} |
||||
|
||||
/// [`[[Delete]] ( P )`][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects-delete-p
|
||||
fn module_namespace_exotic_delete( |
||||
obj: &JsObject, |
||||
key: &PropertyKey, |
||||
context: &mut Context<'_>, |
||||
) -> JsResult<bool> { |
||||
// 1. If P is a Symbol, then
|
||||
// a. Return ! OrdinaryDelete(O, P).
|
||||
let key = match key { |
||||
PropertyKey::Symbol(_) => return ordinary_delete(obj, key, context), |
||||
PropertyKey::Index(_) => return Ok(true), |
||||
PropertyKey::String(s) => s, |
||||
}; |
||||
|
||||
let obj = obj.borrow(); |
||||
let obj = obj |
||||
.as_module_namespace() |
||||
.expect("internal method can only be called on module namespace objects"); |
||||
|
||||
// 2. Let exports be O.[[Exports]].
|
||||
let exports = obj.exports(); |
||||
|
||||
// 3. If exports contains P, return false.
|
||||
// 4. Return true.
|
||||
Ok(!exports.contains_key(key)) |
||||
} |
||||
|
||||
/// [`[[OwnPropertyKeys]] ( )`][spec].
|
||||
///
|
||||
/// [spec]: https://tc39.es/ecma262/#sec-module-namespace-exotic-objects-ownpropertykeys
|
||||
fn module_namespace_exotic_own_property_keys( |
||||
obj: &JsObject, |
||||
context: &mut Context<'_>, |
||||
) -> JsResult<Vec<PropertyKey>> { |
||||
// 2. Let symbolKeys be OrdinaryOwnPropertyKeys(O).
|
||||
let symbol_keys = ordinary_own_property_keys(obj, context)?; |
||||
|
||||
let obj = obj.borrow(); |
||||
let obj = obj |
||||
.as_module_namespace() |
||||
.expect("internal method can only be called on module namespace objects"); |
||||
|
||||
// 1. Let exports be O.[[Exports]].
|
||||
let exports = obj.exports(); |
||||
|
||||
// 3. Return the list-concatenation of exports and symbolKeys.
|
||||
Ok(exports |
||||
.keys() |
||||
.map(|k| PropertyKey::String(k.clone())) |
||||
.chain(symbol_keys) |
||||
.collect()) |
||||
} |
||||
@ -0,0 +1,21 @@
|
||||
function sum(a, b) { |
||||
return a + b; |
||||
} |
||||
|
||||
function sub(a, b) { |
||||
return a - b; |
||||
} |
||||
|
||||
function mult(a, b) { |
||||
return a * b; |
||||
} |
||||
|
||||
function div(a, b) { |
||||
return a / b; |
||||
} |
||||
|
||||
function sqrt(a) { |
||||
return Math.sqrt(a); |
||||
} |
||||
|
||||
export { sum, sub, mult, div, sqrt }; |
||||
@ -0,0 +1,11 @@
|
||||
import { sum, mult, sqrt } from "./operations.mjs"; |
||||
|
||||
function pyth(a, b) { |
||||
let a2 = mult(a, a); |
||||
let b2 = mult(b, b); |
||||
let a2b2 = sum(a2, b2); |
||||
|
||||
return sqrt(a2b2); |
||||
} |
||||
|
||||
export { pyth }; |
||||
@ -0,0 +1,131 @@
|
||||
use std::{error::Error, path::Path}; |
||||
|
||||
use boa_engine::{ |
||||
builtins::promise::PromiseState, |
||||
module::{ModuleLoader, SimpleModuleLoader}, |
||||
object::FunctionObjectBuilder, |
||||
Context, JsError, JsNativeError, JsValue, Module, NativeFunction, |
||||
}; |
||||
use boa_parser::Source; |
||||
|
||||
// This example demonstrates how to use Boa's module API
|
||||
fn main() -> Result<(), Box<dyn Error>> { |
||||
// A simple module that we want to compile from Rust code.
|
||||
const MODULE_SRC: &str = r#" |
||||
import { pyth } from "./trig.mjs"; |
||||
import * as ops from "./operations.mjs"; |
||||
|
||||
export let result = pyth(3, 4); |
||||
export function mix(a, b) { |
||||
return ops.sum(ops.mult(a, ops.sub(b, a)), 10); |
||||
} |
||||
"#; |
||||
|
||||
// This can be overriden with any custom implementation of `ModuleLoader`.
|
||||
let loader = &SimpleModuleLoader::new("./boa_examples/scripts/modules")?; |
||||
let dyn_loader: &dyn ModuleLoader = loader; |
||||
|
||||
// Just need to cast to a `ModuleLoader` before passing it to the builder.
|
||||
let context = &mut Context::builder().module_loader(dyn_loader).build()?; |
||||
let source = Source::from_reader(MODULE_SRC.as_bytes(), Some(Path::new("./main.mjs"))); |
||||
|
||||
// Can also pass a `Some(realm)` if you need to execute the module in another realm.
|
||||
let module = Module::parse(source, None, context)?; |
||||
|
||||
// Don't forget to insert the parsed module into the loader itself! Since the root module
|
||||
// is not automatically inserted by the `ModuleLoader::load_imported_module` impl.
|
||||
//
|
||||
// Simulate as if the "fake" module is located in the modules root, just to ensure that
|
||||
// the loader won't double load in case someone tries to import "./main.mjs".
|
||||
loader.insert( |
||||
Path::new("./boa_examples/scripts/modules") |
||||
.canonicalize()? |
||||
.join("main.mjs"), |
||||
module.clone(), |
||||
); |
||||
|
||||
// The lifecycle of the module is tracked using promises, which can be a bit cumbersome
|
||||
// for simple uses but that use case is better suited by the `Module::load_link_evaluate` method.
|
||||
// This does the full version for demonstration purposes.
|
||||
//
|
||||
// parse -> load -> link -> evaluate
|
||||
let promise_result = module |
||||
// Initial load that recursively loads the module's dependencies.
|
||||
// This returns a `JsPromise` that will be resolved when loading finishes,
|
||||
// which allows async loads and async fetches.
|
||||
.load(context) |
||||
.then( |
||||
Some( |
||||
FunctionObjectBuilder::new( |
||||
context, |
||||
NativeFunction::from_copy_closure_with_captures( |
||||
|_, _, module, context| { |
||||
// After loading, link all modules by resolving the imports
|
||||
// and exports on the full module graph, initializing module
|
||||
// environments. This returns a plain `Err` since all modules
|
||||
// must link at the same time.
|
||||
module.link(context)?; |
||||
Ok(JsValue::undefined()) |
||||
}, |
||||
module.clone(), |
||||
), |
||||
) |
||||
.build(), |
||||
), |
||||
None, |
||||
context, |
||||
)? |
||||
.then( |
||||
Some( |
||||
FunctionObjectBuilder::new( |
||||
context, |
||||
NativeFunction::from_copy_closure_with_captures( |
||||
// Finally, evaluate the root module.
|
||||
// This returns a `JsPromise` since a module could have
|
||||
// top-level await statements, which defers module execution to the
|
||||
// job queue.
|
||||
|_, _, module, context| Ok(module.evaluate(context).into()), |
||||
module.clone(), |
||||
), |
||||
) |
||||
.build(), |
||||
), |
||||
None, |
||||
context, |
||||
)?; |
||||
|
||||
// Very important to push forward the job queue after queueing promises.
|
||||
context.run_jobs(); |
||||
|
||||
// Checking if the final promise didn't return an error.
|
||||
match promise_result.state()? { |
||||
PromiseState::Pending => return Err("module didn't execute!".into()), |
||||
PromiseState::Fulfilled(v) => { |
||||
assert_eq!(v, JsValue::undefined()) |
||||
} |
||||
PromiseState::Rejected(err) => { |
||||
return Err(JsError::from_opaque(err).try_native(context)?.into()) |
||||
} |
||||
} |
||||
|
||||
// We can access the full namespace of the module with all its exports.
|
||||
let namespace = module.namespace(context); |
||||
let result = namespace.get("result", context)?; |
||||
|
||||
println!("result = {}", result.display()); |
||||
|
||||
assert_eq!(namespace.get("result", context)?, JsValue::from(5)); |
||||
|
||||
let mix = namespace |
||||
.get("mix", context)? |
||||
.as_callable() |
||||
.cloned() |
||||
.ok_or_else(|| JsNativeError::typ().with_message("mix export wasn't a function!"))?; |
||||
let result = mix.call(&JsValue::undefined(), &[5.into(), 10.into()], context)?; |
||||
|
||||
println!("mix(5, 10) = {}", result.display()); |
||||
|
||||
assert_eq!(result, 35.into()); |
||||
|
||||
Ok(()) |
||||
} |
||||
Loading…
Reference in new issue