oden/third-party/vendor/swc_ecma_parser/src/lib.rs
2024-03-08 11:03:01 -08:00

508 lines
13 KiB
Rust

//! EcmaScript/TypeScript parser for the rust programming language.
//!
//! # Features
//!
//! ## Heavily tested
//!
//! Passes almost all tests from [tc39/test262][].
//!
//! ## Error reporting
//!
//! ```sh
//! error: 'implements', 'interface', 'let', 'package', 'private', 'protected', 'public', 'static', or 'yield' cannot be used as an identifier in strict mode
//! --> invalid.js:3:10
//! |
//! 3 | function yield() {
//! | ^^^^^
//! ```
//!
//! ## Error recovery
//!
//! The parser can recover from some parsing errors. For example, parser returns
//! `Ok(Module)` for the code below, while emitting error to handler.
//!
//! ```ts
//! const CONST = 9000 % 2;
//! const enum D {
//! // Comma is required, but parser can recover because of the newline.
//! d = 10
//! g = CONST
//! }
//! ```
//!
//! # Example (lexer)
//!
//! See `lexer.rs` in examples directory.
//!
//! # Example (parser)
//!
//! ```
//! #[macro_use]
//! extern crate swc_common;
//! extern crate swc_ecma_parser;
//! use swc_common::sync::Lrc;
//! use swc_common::{
//! errors::{ColorConfig, Handler},
//! FileName, FilePathMapping, SourceMap,
//! };
//! use swc_ecma_parser::{lexer::Lexer, Parser, StringInput, Syntax};
//!
//! fn main() {
//! let cm: Lrc<SourceMap> = Default::default();
//! let handler =
//! Handler::with_tty_emitter(ColorConfig::Auto, true, false,
//! Some(cm.clone()));
//!
//! // Real usage
//! // let fm = cm
//! // .load_file(Path::new("test.js"))
//! // .expect("failed to load test.js");
//! let fm = cm.new_source_file(
//! FileName::Custom("test.js".into()),
//! "function foo() {}".into(),
//! );
//! let lexer = Lexer::new(
//! // We want to parse ecmascript
//! Syntax::Es(Default::default()),
//! // EsVersion defaults to es5
//! Default::default(),
//! StringInput::from(&*fm),
//! None,
//! );
//!
//! let mut parser = Parser::new_from(lexer);
//!
//! for e in parser.take_errors() {
//! e.into_diagnostic(&handler).emit();
//! }
//!
//! let _module = parser
//! .parse_module()
//! .map_err(|mut e| {
//! // Unrecoverable fatal error occurred
//! e.into_diagnostic(&handler).emit()
//! })
//! .expect("failed to parser module");
//! }
//! ```
//!
//! ## Cargo features
//!
//! ### `typescript`
//!
//! Enables typescript parser.
//!
//! ### `verify`
//!
//! Verify more errors, using `swc_ecma_visit`.
//!
//! ## Known issues
//!
//! ### Null character after `\`
//!
//! Because [String] of rust should only contain valid utf-8 characters while
//! javascript allows non-utf8 characters, the parser stores invalid utf8
//! characters in escaped form.
//!
//! As a result, swc needs a way to distinguish invalid-utf8 code points and
//! input specified by the user. The parser stores a null character right after
//! `\\` for non-utf8 code points. Note that other parts of swc is aware of this
//! fact.
//!
//! Note that this can be changed at anytime with a breaking change.
//!
//! [tc39/test262]:https://github.com/tc39/test262
#![cfg_attr(docsrs, feature(doc_cfg))]
#![cfg_attr(test, feature(test))]
#![deny(clippy::all)]
#![deny(unused)]
#![allow(clippy::nonminimal_bool)]
#![allow(clippy::too_many_arguments)]
#![allow(clippy::unnecessary_unwrap)]
#![allow(clippy::vec_box)]
#![allow(clippy::wrong_self_convention)]
#![allow(clippy::match_like_matches_macro)]
use error::Error;
use lexer::Lexer;
use serde::{Deserialize, Serialize};
use swc_common::{comments::Comments, input::SourceFileInput, SourceFile};
use swc_ecma_ast::*;
pub use self::{
lexer::input::{Input, StringInput},
parser::*,
};
#[deprecated(note = "Use `EsVersion` instead")]
pub type JscTarget = EsVersion;
#[macro_use]
mod macros;
pub mod error;
pub mod lexer;
mod parser;
pub mod token;
#[derive(Debug, Clone, Copy, PartialEq, Eq, Deserialize, Serialize)]
#[serde(deny_unknown_fields, tag = "syntax")]
pub enum Syntax {
/// Standard
#[serde(rename = "ecmascript")]
Es(EsConfig),
/// This variant requires the cargo feature `typescript` to be enabled.
#[cfg(feature = "typescript")]
#[cfg_attr(docsrs, doc(cfg(feature = "typescript")))]
#[serde(rename = "typescript")]
Typescript(TsConfig),
}
impl Default for Syntax {
fn default() -> Self {
Syntax::Es(Default::default())
}
}
impl Syntax {
fn auto_accessors(self) -> bool {
match self {
Syntax::Es(EsConfig {
auto_accessors: true,
..
}) => true,
Syntax::Typescript(_) => true,
_ => false,
}
}
pub fn import_attributes(self) -> bool {
match self {
Syntax::Es(EsConfig {
import_attributes, ..
}) => import_attributes,
Syntax::Typescript(_) => true,
}
}
/// Should we parse jsx?
pub fn jsx(self) -> bool {
matches!(
self,
Syntax::Es(EsConfig { jsx: true, .. }) | Syntax::Typescript(TsConfig { tsx: true, .. })
)
}
pub fn fn_bind(self) -> bool {
matches!(self, Syntax::Es(EsConfig { fn_bind: true, .. }))
}
pub fn decorators(self) -> bool {
matches!(
self,
Syntax::Es(EsConfig {
decorators: true,
..
}) | Syntax::Typescript(TsConfig {
decorators: true,
..
})
)
}
pub fn decorators_before_export(self) -> bool {
matches!(
self,
Syntax::Es(EsConfig {
decorators_before_export: true,
..
}) | Syntax::Typescript(..)
)
}
/// Should we parse typescript?
#[cfg(not(feature = "typescript"))]
pub const fn typescript(self) -> bool {
false
}
/// Should we parse typescript?
#[cfg(feature = "typescript")]
pub const fn typescript(self) -> bool {
matches!(self, Syntax::Typescript(..))
}
pub fn export_default_from(self) -> bool {
matches!(
self,
Syntax::Es(EsConfig {
export_default_from: true,
..
})
)
}
pub fn dts(self) -> bool {
match self {
Syntax::Typescript(t) => t.dts,
_ => false,
}
}
pub(crate) fn allow_super_outside_method(self) -> bool {
match self {
Syntax::Es(EsConfig {
allow_super_outside_method,
..
}) => allow_super_outside_method,
Syntax::Typescript(_) => true,
}
}
pub(crate) fn allow_return_outside_function(self) -> bool {
match self {
Syntax::Es(EsConfig {
allow_return_outside_function,
..
}) => allow_return_outside_function,
Syntax::Typescript(_) => false,
}
}
pub(crate) fn early_errors(self) -> bool {
match self {
Syntax::Typescript(t) => !t.no_early_errors,
Syntax::Es(..) => true,
}
}
fn disallow_ambiguous_jsx_like(self) -> bool {
match self {
Syntax::Typescript(t) => t.disallow_ambiguous_jsx_like,
_ => false,
}
}
pub fn explicit_resource_management(&self) -> bool {
match self {
Syntax::Es(EsConfig {
explicit_resource_management: using_decl,
..
}) => *using_decl,
Syntax::Typescript(_) => true,
}
}
}
#[derive(Debug, Clone, Copy, PartialEq, Eq, Default, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct TsConfig {
#[serde(default)]
pub tsx: bool,
#[serde(default)]
pub decorators: bool,
/// `.d.ts`
#[serde(skip, default)]
pub dts: bool,
#[serde(skip, default)]
pub no_early_errors: bool,
/// babel: `disallowAmbiguousJSXLike`
/// Even when JSX parsing is not enabled, this option disallows using syntax
/// that would be ambiguous with JSX (`<X> y` type assertions and
/// `<X>()=>{}` type arguments)
/// see: https://babeljs.io/docs/en/babel-plugin-transform-typescript#disallowambiguousjsxlike
#[serde(skip, default)]
pub disallow_ambiguous_jsx_like: bool,
}
#[derive(Debug, Clone, Copy, PartialEq, Eq, Default, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct EsConfig {
#[serde(default)]
pub jsx: bool,
/// Support function bind expression.
#[serde(rename = "functionBind")]
#[serde(default)]
pub fn_bind: bool,
/// Enable decorators.
#[serde(default)]
pub decorators: bool,
/// babel: `decorators.decoratorsBeforeExport`
///
/// Effective only if `decorator` is true.
#[serde(rename = "decoratorsBeforeExport")]
#[serde(default)]
pub decorators_before_export: bool,
#[serde(default)]
pub export_default_from: bool,
/// Stage 3.
#[serde(default, alias = "importAssertions")]
pub import_attributes: bool,
#[serde(default, rename = "allowSuperOutsideMethod")]
pub allow_super_outside_method: bool,
#[serde(default, rename = "allowReturnOutsideFunction")]
pub allow_return_outside_function: bool,
#[serde(default)]
pub auto_accessors: bool,
#[serde(default)]
pub explicit_resource_management: bool,
}
/// Syntactic context.
#[derive(Debug, Clone, Copy, Default)]
pub struct Context {
/// `true` while backtracking
ignore_error: bool,
/// Is in module code?
module: bool,
can_be_module: bool,
strict: bool,
expr_ctx: ExpressionContext,
include_in_expr: bool,
/// If true, await expression is parsed, and "await" is treated as a
/// keyword.
in_async: bool,
/// If true, yield expression is parsed, and "yield" is treated as a
/// keyword.
in_generator: bool,
is_continue_allowed: bool,
is_break_allowed: bool,
in_type: bool,
/// Typescript extension.
should_not_lex_lt_or_gt_as_type: bool,
/// Typescript extension.
in_declare: bool,
/// If true, `:` should not be treated as a type annotation.
in_cond_expr: bool,
will_expect_colon_for_cond: bool,
in_class: bool,
in_class_field: bool,
in_function: bool,
/// This indicates current scope or the scope out of arrow function is
/// function declaration or function expression or not.
inside_non_arrow_function_scope: bool,
in_parameters: bool,
has_super_class: bool,
in_property_name: bool,
in_forced_jsx_context: bool,
// If true, allow super.x and super[x]
allow_direct_super: bool,
ignore_else_clause: bool,
disallow_conditional_types: bool,
allow_using_decl: bool,
}
#[derive(Debug, Clone, Copy, Default)]
struct ExpressionContext {
// TODO:
// - include_in
for_loop_init: bool,
for_await_loop_init: bool,
}
#[cfg(test)]
fn with_test_sess<F, Ret>(src: &str, f: F) -> Result<Ret, ::testing::StdErr>
where
F: FnOnce(&swc_common::errors::Handler, StringInput<'_>) -> Result<Ret, ()>,
{
use swc_common::FileName;
::testing::run_test(false, |cm, handler| {
let fm = cm.new_source_file(FileName::Real("testing".into()), src.into());
f(handler, (&*fm).into())
})
}
pub fn with_file_parser<T>(
fm: &SourceFile,
syntax: Syntax,
target: EsVersion,
comments: Option<&dyn Comments>,
recovered_errors: &mut Vec<Error>,
op: impl for<'aa> FnOnce(&mut Parser<Lexer>) -> PResult<T>,
) -> PResult<T> {
let lexer = Lexer::new(syntax, target, SourceFileInput::from(fm), comments);
let mut p = Parser::new_from(lexer);
let ret = op(&mut p);
recovered_errors.append(&mut p.take_errors());
ret
}
macro_rules! expose {
(
$name:ident,
$T:ty,
$($t:tt)*
) => {
/// Note: This is recommended way to parse a file.
///
/// This is an alias for [Parser], [Lexer] and [SourceFileInput], but
/// instantiation of generics occur in `swc_ecma_parser` crate.
pub fn $name(
fm: &SourceFile,
syntax: Syntax,
target: EsVersion,
comments: Option<&dyn Comments>,
recovered_errors: &mut Vec<Error>,
) -> PResult<$T> {
with_file_parser(fm, syntax, target, comments, recovered_errors, $($t)*)
}
};
}
expose!(parse_file_as_expr, Box<Expr>, |p| {
// This allow to parse `import.meta`
p.input().ctx.can_be_module = true;
p.parse_expr()
});
expose!(parse_file_as_module, Module, |p| { p.parse_module() });
expose!(parse_file_as_script, Script, |p| { p.parse_script() });
expose!(parse_file_as_program, Program, |p| { p.parse_program() });
#[inline(always)]
#[cfg(any(target_arch = "wasm32", target_arch = "arm", not(feature = "stacker")))]
fn maybe_grow<R, F: FnOnce() -> R>(_red_zone: usize, _stack_size: usize, callback: F) -> R {
callback()
}
#[inline(always)]
#[cfg(all(
not(any(target_arch = "wasm32", target_arch = "arm")),
feature = "stacker"
))]
fn maybe_grow<R, F: FnOnce() -> R>(red_zone: usize, stack_size: usize, callback: F) -> R {
stacker::maybe_grow(red_zone, stack_size, callback)
}