Adds no_std support for some sub-crates

boa_ast/Cargo.toml

@@ -11,15 +11,15 @@ repository.workspace = true
 rust-version.workspace = true
 
 [features]
-serde = ["boa_interner/serde", "dep:serde"]
+serde = ["dep:serde", "boa_interner/serde"]
 
-fuzz = ["arbitrary", "boa_interner/fuzz", "num-bigint/arbitrary"]
+arbitrary = ["dep:arbitrary", "boa_interner/arbitrary", "num-bigint/arbitrary"]
 
 [dependencies]
 boa_interner.workspace = true
 boa_macros.workspace = true
 rustc-hash = "1.1.0"
-serde = { version = "1.0.152", features = ["derive"], optional = true }
 bitflags = "1.3.2"
 num-bigint = "0.4.3"
-arbitrary = { version = "1", optional = true, features = ["derive"] }
+serde = { version = "1.0.152", features = ["derive"], optional = true }
+arbitrary = { version = "1", features = ["derive"], optional = true }

boa_engine/Cargo.toml

@@ -28,7 +28,7 @@ intl = [
     "dep:sys-locale",
 ]
 
-fuzz = ["boa_ast/fuzz", "boa_interner/fuzz"]
+fuzz = ["boa_ast/arbitrary", "boa_interner/arbitrary"]
 
 # Enable Boa's VM instruction flowgraph generator.
 flowgraph = []

boa_icu_provider/Cargo.toml

@@ -2,7 +2,7 @@
 name = "boa_icu_provider"
 description = "ICU4X data provider for the Boa JavaScript engine."
 keywords = ["javascript", "cldr", "unicode"]
-categories = ["internationalization"]
+categories = ["internationalization", "no-std"]
 version.workspace = true
 edition.workspace = true
 authors.workspace = true
@@ -15,13 +15,15 @@ rust-version.workspace = true
 [dependencies]
 icu_provider = { version = "1.0.1", features = ["serde", "sync"] }
 icu_provider_blob = "1.0.0"
-icu_provider_adapters = { version = "1.0.0", features = ["serde"]}
+icu_provider_adapters = { version = "1.0.0", features = ["serde"] }
+once_cell = {version = "1.17.0", default-features = false, features = ["critical-section"]}
 icu_datagen = { version = "1.0.2", optional = true }
 log = { version = "0.4.17", optional = true }
 simple_logger = { version = "4.0.0", optional = true }
-once_cell = "1.17.0"
 
 [features]
+default = ["std"]
+std = ["once_cell/std"]
 bin = ["dep:icu_datagen", "dep:simple_logger", "dep:log"]
 
 [[bin]]

boa_icu_provider/src/lib.rs

@@ -64,8 +64,10 @@
     clippy::pedantic,
     clippy::nursery,
 )]
+#![cfg_attr(not(feature = "bin"), no_std)]
 
 /// Gets the path to the directory where the generated data is stored.
+#[cfg(feature = "bin")]
 #[must_use]
 #[doc(hidden)]
 pub fn data_root() -> std::path::PathBuf {

boa_interner/Cargo.toml

@@ -2,7 +2,7 @@
 name = "boa_interner"
 description = "String interner for the Boa JavaScript engine."
 keywords = ["javascript", "js", "string", "interner"]
-categories = ["data-structures"]
+categories = ["data-structures", "no-std"]
 version.workspace = true
 edition.workspace = true
 authors.workspace = true
@@ -11,14 +11,16 @@ repository.workspace = true
 rust-version.workspace = true
 
 [features]
-fuzz = ["arbitrary"]
+default = ["std"]
+std = ["once_cell/std"]
 
 [dependencies]
 boa_macros.workspace = true
-serde = { version = "1.0.152", features = ["derive"], optional = true }
-phf = { version = "0.11.1", features = ["macros"] }
-rustc-hash = "1.1.0"
+phf = { version = "0.11.1", default-features = false, features = ["macros"] }
+rustc-hash = { version = "1.1.0", default-features = false }
 static_assertions = "1.1.0"
-once_cell = "1.17.0"
+once_cell = {version = "1.17.0", default-features = false, features = ["critical-section"]}
 indexmap = "1.9.2"
-arbitrary = { version = "1", optional = true, features = ["derive"] }
+serde = { version = "1.0.152", features = ["derive"], optional = true }
+arbitrary = { version = "1", features = ["derive"], optional = true }
+hashbrown = { version = "0.13.2", default-features = false, features = ["inline-more"] }

boa_interner/src/fixed_string.rs

@@ -1,3 +1,5 @@
+use alloc::vec::Vec;
+
 use crate::interned_str::InternedStr;
 
 #[derive(Debug)]

boa_interner/src/interned_str.rs

@@ -1,4 +1,4 @@
-use std::{hash::Hash, ptr::NonNull};
+use core::{hash::Hash, ptr::NonNull};
 
 /// Wrapper for an interned str pointer, required to
 /// quickly check using a hash if a string is inside an [`Interner`][`super::Interner`].
@@ -69,7 +69,7 @@ impl<Char> Hash for InternedStr<Char>
 where
     Char: Hash,
 {
-    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
+    fn hash<H: core::hash::Hasher>(&self, state: &mut H) {
         // SAFETY:
         // The caller must ensure `ptr` is still valid throughout the
         // lifetime of `self`.

boa_interner/src/lib.rs

@@ -89,6 +89,9 @@
     // TODO deny once false positive is fixed (https://github.com/rust-lang/rust-clippy/issues/9626).
     clippy::trait_duplication_in_bounds
 )]
+#![cfg_attr(not(feature = "arbitrary"), no_std)]
+
+extern crate alloc;
 
 extern crate static_assertions as sa;
 
@@ -100,8 +103,8 @@ mod sym;
 #[cfg(test)]
 mod tests;
 
+use alloc::{borrow::Cow, format, string::String};
 use raw::RawInterner;
-use std::borrow::Cow;
 
 pub use sym::*;
 
@@ -213,10 +216,10 @@ impl<'a, 'b> JSInternedStrRef<'a, 'b> {
     }
 }
 
-impl std::fmt::Display for JSInternedStrRef<'_, '_> {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+impl core::fmt::Display for JSInternedStrRef<'_, '_> {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
         self.join_with_context(
-            std::fmt::Display::fmt,
+            core::fmt::Display::fmt,
             |js, f| {
                 char::decode_utf16(js.iter().copied())
                     .map(|r| match r {
@@ -395,7 +398,7 @@ impl Interner {
             // We only manipulate valid UTF-8 `str`s and convert them to `[u8]` for convenience,
             // so converting back to a `str` is safe.
             let utf8 = unsafe {
-                std::str::from_utf8_unchecked(
+                core::str::from_utf8_unchecked(
                     self.utf8_interner
                         .index(index)
                         .expect("both interners must have the same size"),

boa_interner/src/raw.rs

@@ -1,6 +1,10 @@
 use crate::{fixed_string::FixedString, interned_str::InternedStr};
-use rustc_hash::FxHashMap;
-use std::hash::Hash;
+use alloc::vec::Vec;
+use core::hash::{BuildHasherDefault, Hash};
+use hashbrown::HashMap;
+use rustc_hash::FxHasher;
+
+type Map<T, U> = HashMap<T, U, BuildHasherDefault<FxHasher>>;
 
 /// Raw string interner, generic by a char type.
 #[derive(Debug)]
@@ -17,7 +21,7 @@ pub(super) struct RawInterner<Char> {
     // please check out https://github.com/Robbepop/string-interner/pull/47 first.
     // This doesn't implement that method, since implementing it increases
     // our memory footprint.
-    symbol_cache: FxHashMap<InternedStr<Char>, usize>,
+    symbol_cache: Map<InternedStr<Char>, usize>,
     spans: Vec<InternedStr<Char>>,
     head: FixedString<Char>,
     full: Vec<FixedString<Char>>,
@@ -26,7 +30,7 @@ pub(super) struct RawInterner<Char> {
 impl<Char> Default for RawInterner<Char> {
     fn default() -> Self {
         Self {
-            symbol_cache: FxHashMap::default(),
+            symbol_cache: Map::default(),
             spans: Vec::default(),
             head: FixedString::default(),
             full: Vec::default(),
@@ -38,7 +42,7 @@ impl<Char> RawInterner<Char> {
     /// Creates a new `RawInterner` with the specified capacity.
     pub(super) fn with_capacity(capacity: usize) -> Self {
         Self {
-            symbol_cache: FxHashMap::default(),
+            symbol_cache: Map::default(),
             spans: Vec::with_capacity(capacity),
             head: FixedString::new(capacity),
             full: Vec::new(),
@@ -167,7 +171,7 @@ where
                 let new_cap =
                     (usize::max(self.head.capacity(), string.len()) + 1).next_power_of_two();
                 let new_head = FixedString::new(new_cap);
-                let old_head = std::mem::replace(&mut self.head, new_head);
+                let old_head = core::mem::replace(&mut self.head, new_head);
 
                 // If the user creates an `Interner`
                 // with `Interner::with_capacity(BIG_NUMBER)` and

boa_interner/src/sym.rs

@@ -1,20 +1,23 @@
 use boa_macros::utf16;
+use core::{hash::BuildHasherDefault, num::NonZeroUsize};
 use indexmap::IndexSet;
 use once_cell::sync::Lazy;
-use std::num::NonZeroUsize;
+use rustc_hash::FxHasher;
 
-#[cfg(feature = "serde")]
-use serde::{Deserialize, Serialize};
+type Set<T> = IndexSet<T, BuildHasherDefault<FxHasher>>;
 
 /// The string symbol type for Boa.
 ///
 /// This symbol type is internally a `NonZeroUsize`, which makes it pointer-width in size and it's
 /// optimized so that it can occupy 1 pointer width even in an `Option` type.
-#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
-#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[cfg_attr(feature = "serde", serde(transparent))]
-#[cfg_attr(feature = "fuzz", derive(arbitrary::Arbitrary))]
+#[cfg_attr(
+    feature = "serde",
+    derive(serde::Serialize, serde::Deserialize),
+    serde(transparent)
+)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 #[allow(clippy::unsafe_derive_deserialize)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct Sym {
     value: NonZeroUsize,
 }
@@ -162,8 +165,8 @@ macro_rules! create_static_strings {
         /// `COMMON_STRINGS_UTF8`, `COMMON_STRINGS_UTF16` and the constants
         /// defined in [`Sym`] must always be in sync.
         // FIXME: use phf when const expressions are allowed. https://github.com/rust-phf/rust-phf/issues/188
-        pub(super) static COMMON_STRINGS_UTF16: Lazy<IndexSet<&'static [u16]>> = Lazy::new(|| {
-            let mut set = IndexSet::with_capacity(COMMON_STRINGS_UTF8.len());
+        pub(super) static COMMON_STRINGS_UTF16: Lazy<Set<&'static [u16]>> = Lazy::new(|| {
+            let mut set = Set::with_capacity_and_hasher(COMMON_STRINGS_UTF8.len(), BuildHasherDefault::default());
             $( set.insert(utf16!($s)); )+
             set
         });

boa_macros/src/lib.rs

@@ -151,7 +151,7 @@ fn derive_trace(mut s: Structure<'_>) -> proc_macro2::TokenStream {
     // type and encourage people to use Finalize. This implementation will
     // call `Finalize::finalize` if it is safe to do so.
     let drop_impl = s.unbound_impl(
-        quote!(::std::ops::Drop),
+        quote!(::core::ops::Drop),
         quote! {
             fn drop(&mut self) {
                 if ::boa_gc::finalizer_safe() {

boa_profiler/src/lib.rs

@@ -77,8 +77,9 @@
     clippy::pedantic,
     clippy::nursery,
 )]
+#![cfg_attr(not(feature = "profiler"), no_std)]
 
-use std::fmt::{self, Debug};
+use core::fmt::{self, Debug};
 
 #[cfg(feature = "profiler")]
 use measureme::{EventId, Profiler as MeasuremeProfiler, StringId, TimingGuard};

boa_unicode/Cargo.toml

@@ -2,7 +2,7 @@
 name = "boa_unicode"
 description = "Unicode support for the Boa JavaScript engine."
 keywords = ["javascript", "compiler", "lexer", "parser", "unicode"]
-categories = ["parsing"]
+categories = ["parsing", "no-std"]
 version.workspace = true
 edition.workspace = true
 authors.workspace = true

boa_unicode/src/lib.rs

@@ -87,6 +87,7 @@
     clippy::nursery,
 )]
 #![allow(clippy::redundant_pub_crate)]
+#![no_std]
 
 mod tables;
 #[cfg(test)]