git.delta.rocks / jrsonnet / refs/commits / b3f009bb7b2e

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crates/jrsonnet-evaluator/src/lib.rs14.7 KiBsourcehistory
1//! jsonnet interpreter implementation2#![cfg_attr(nightly, feature(thread_local, type_alias_impl_trait))]34// For jrsonnet-macros5extern crate self as jrsonnet_evaluator;67mod arr;8pub mod async_import;9mod ctx;10mod dynamic;11pub mod error;12mod evaluate;13pub mod function;14pub mod gc;15mod import;16mod integrations;17pub mod manifest;18mod map;19mod obj;20pub mod stack;21pub mod stdlib;22mod tla;23pub mod trace;24pub mod typed;25pub mod val;2627use std::{28	any::Any,29	cell::{RefCell, RefMut},30	clone::Clone,31	collections::hash_map::Entry,32	fmt::{self, Debug},33	marker::PhantomData,34	rc::Rc,35};3637pub use ctx::*;38pub use dynamic::*;39pub use error::{Error, ErrorKind::*, Result, ResultExt};40pub use evaluate::*;41use function::CallLocation;42pub use import::*;43use jrsonnet_gcmodule::{cc_dyn, Cc, Trace};44pub use jrsonnet_interner::{IBytes, IStr};45#[doc(hidden)]46pub use jrsonnet_macros;47pub use jrsonnet_parser as parser;48use jrsonnet_parser::{Expr, ParserSettings, Source, SourcePath, Spanned};49pub use obj::*;50pub use rustc_hash;51use rustc_hash::FxHashMap;52use stack::check_depth;53pub use tla::apply_tla;54pub use val::{Thunk, Val};5556use crate::gc::WithCapacityExt as _;5758cc_dyn!(59	#[derive(Clone)]60	CcUnbound<V>,61	Unbound<Bound = V>62);6364/// Thunk without bound `super`/`this`65/// object inheritance may be overriden multiple times, and will be fixed only on field read66pub trait Unbound: Trace {67	/// Type of value after object context is bound68	type Bound;69	/// Create value bound to specified object context70	fn bind(&self, sup_this: SupThis) -> Result<Self::Bound>;71}7273/// Object fields may, or may not depend on `this`/`super`, this enum allows cheaper reuse of object-independent fields for native code74/// Standard jsonnet fields are always unbound75#[derive(Clone, Trace)]76pub enum MaybeUnbound {77	/// Value needs to be bound to `this`/`super`78	Unbound(CcUnbound<Val>),79	/// Value is object-independent80	Bound(Thunk<Val>),81}8283impl Debug for MaybeUnbound {84	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {85		write!(f, "MaybeUnbound")86	}87}88impl MaybeUnbound {89	/// Attach object context to value, if required90	pub fn evaluate(&self, sup_this: SupThis) -> Result<Val> {91		match self {92			Self::Unbound(v) => v.0.bind(sup_this),93			Self::Bound(v) => Ok(v.evaluate()?),94		}95	}96}9798cc_dyn!(CcContextInitializer, ContextInitializer);99100/// During import, this trait will be called to create initial context for file.101/// It may initialize global variables, stdlib for example.102pub trait ContextInitializer: Trace {103	/// For which size the builder should be preallocated104	fn reserve_vars(&self) -> usize {105		0106	}107	/// Initialize default file context.108	/// Has default implementation, which calls `populate`.109	/// Prefer to always implement `populate` instead.110	fn initialize(&self, for_file: Source) -> Context {111		let mut builder = ContextBuilder::with_capacity(self.reserve_vars());112		self.populate(for_file, &mut builder);113		builder.build()114	}115	/// For composability: extend builder. May panic if this initialization is not supported,116	/// and the context may only be created via `initialize`.117	fn populate(&self, for_file: Source, builder: &mut ContextBuilder);118	/// Allows upcasting from abstract to concrete context initializer.119	/// jrsonnet by itself doesn't use this method, it is allowed for it to panic.120	fn as_any(&self) -> &dyn Any;121}122123/// Context initializer which adds nothing.124impl ContextInitializer for () {125	fn populate(&self, _for_file: Source, _builder: &mut ContextBuilder) {}126	fn as_any(&self) -> &dyn Any {127		self128	}129}130131impl<T> ContextInitializer for Option<T>132where133	T: ContextInitializer,134{135	fn initialize(&self, for_file: Source) -> Context {136		if let Some(ctx) = self {137			ctx.initialize(for_file)138		} else {139			().initialize(for_file)140		}141	}142143	fn populate(&self, for_file: Source, builder: &mut ContextBuilder) {144		if let Some(ctx) = self {145			ctx.populate(for_file, builder);146		}147	}148149	fn as_any(&self) -> &dyn Any {150		self151	}152}153154macro_rules! impl_context_initializer {155	($($gen:ident)*) => {156		#[allow(non_snake_case)]157		impl<$($gen: ContextInitializer + Trace,)*> ContextInitializer for ($($gen,)*) {158			fn reserve_vars(&self) -> usize {159				let mut out = 0;160				let ($($gen,)*) = self;161				$(out += $gen.reserve_vars();)*162				out163			}164			fn populate(&self, for_file: Source, builder: &mut ContextBuilder) {165				let ($($gen,)*) = self;166				$($gen.populate(for_file.clone(), builder);)*167			}168			fn as_any(&self) -> &dyn Any {169				self170			}171		}172	};173	($($cur:ident)* @ $c:ident $($rest:ident)*) => {174		impl_context_initializer!($($cur)*);175		impl_context_initializer!($($cur)* $c @ $($rest)*);176	};177	($($cur:ident)* @) => {178		impl_context_initializer!($($cur)*);179	}180}181impl_context_initializer! {182	A @ B C D E F G183}184185#[derive(Trace)]186struct FileData {187	string: Option<IStr>,188	bytes: Option<IBytes>,189	parsed: Option<Rc<Spanned<Expr>>>,190	evaluated: Option<Val>,191192	evaluating: bool,193}194impl FileData {195	fn new_string(data: IStr) -> Self {196		Self {197			string: Some(data),198			bytes: None,199			parsed: None,200			evaluated: None,201			evaluating: false,202		}203	}204	fn new_bytes(data: IBytes) -> Self {205		Self {206			string: None,207			bytes: Some(data),208			parsed: None,209			evaluated: None,210			evaluating: false,211		}212	}213	pub(crate) fn get_string(&mut self) -> Option<IStr> {214		if self.string.is_none() {215			self.string = Some(216				self.bytes217					.as_ref()218					.expect("either string or bytes should be set")219					.clone()220					.cast_str()?,221			);222		}223		Some(self.string.clone().expect("just set"))224	}225}226227#[derive(Trace)]228pub struct EvaluationStateInternals {229	/// Internal state230	file_cache: RefCell<FxHashMap<SourcePath, FileData>>,231	/// Context initializer, which will be used for imports and everything232	/// [`NoopContextInitializer`] is used by default, most likely you want to have `jrsonnet-stdlib`233	context_initializer: CcContextInitializer,234	/// Used to resolve file locations/contents235	import_resolver: Rc<dyn ImportResolver>,236}237238/// Maintains stack trace and import resolution239#[derive(Clone, Trace)]240pub struct State(Cc<EvaluationStateInternals>);241242thread_local! {243	pub static DEFAULT_STATE: State = State::builder().build();244	pub static STATE: RefCell<Option<State>> = const {RefCell::new(None)};245}246pub struct StateEnterGuard(PhantomData<()>);247impl Drop for StateEnterGuard {248	fn drop(&mut self) {249		STATE.with_borrow_mut(|v| *v = None);250	}251}252253pub fn with_state<V>(v: impl FnOnce(State) -> V) -> V {254	if let Some(state) = STATE.with_borrow(Clone::clone) {255		v(state)256	} else {257		let s = DEFAULT_STATE.with(Clone::clone);258		v(s)259	}260}261262impl State {263	pub fn enter(&self) -> StateEnterGuard {264		self.try_enter().expect("entered state already exists")265	}266	pub fn try_enter(&self) -> Option<StateEnterGuard> {267		STATE.with_borrow_mut(|v| {268			if v.is_none() {269				*v = Some(self.clone());270				Some(StateEnterGuard(PhantomData))271			} else {272				None273			}274		})275	}276	/// Should only be called with path retrieved from [`resolve_path`], may panic otherwise277	pub fn import_resolved_str(&self, path: SourcePath) -> Result<IStr> {278		let mut file_cache = self.file_cache();279		let mut file = file_cache.entry(path.clone());280281		let file = match file {282			Entry::Occupied(ref mut d) => d.get_mut(),283			Entry::Vacant(v) => {284				let data = self.import_resolver().load_file_contents(&path)?;285				v.insert(FileData::new_string(286					std::str::from_utf8(&data)287						.map_err(|_| ImportBadFileUtf8(path.clone()))?288						.into(),289				))290			}291		};292		Ok(file293			.get_string()294			.ok_or_else(|| ImportBadFileUtf8(path.clone()))?)295	}296	/// Should only be called with path retrieved from [`resolve_path`], may panic otherwise297	pub fn import_resolved_bin(&self, path: SourcePath) -> Result<IBytes> {298		let mut file_cache = self.file_cache();299		let mut file = file_cache.entry(path.clone());300301		let file = match file {302			Entry::Occupied(ref mut d) => d.get_mut(),303			Entry::Vacant(v) => {304				let data = self.import_resolver().load_file_contents(&path)?;305				v.insert(FileData::new_bytes(data.as_slice().into()))306			}307		};308		if let Some(str) = &file.bytes {309			return Ok(str.clone());310		}311		if file.bytes.is_none() {312			file.bytes = Some(313				file.string314					.as_ref()315					.expect("either string or bytes should be set")316					.clone()317					.cast_bytes(),318			);319		}320		Ok(file.bytes.as_ref().expect("just set").clone())321	}322	/// Should only be called with path retrieved from [`resolve_path`], may panic otherwise323	pub fn import_resolved(&self, path: SourcePath) -> Result<Val> {324		let mut file_cache = self.file_cache();325		let mut file = file_cache.entry(path.clone());326327		let file = match file {328			Entry::Occupied(ref mut d) => d.get_mut(),329			Entry::Vacant(v) => {330				let data = self.import_resolver().load_file_contents(&path)?;331				v.insert(FileData::new_string(332					std::str::from_utf8(&data)333						.map_err(|_| ImportBadFileUtf8(path.clone()))?334						.into(),335				))336			}337		};338		if let Some(val) = &file.evaluated {339			return Ok(val.clone());340		}341		let code = file342			.get_string()343			.ok_or_else(|| ImportBadFileUtf8(path.clone()))?;344		let file_name = Source::new(path.clone(), code.clone());345		if file.parsed.is_none() {346			file.parsed = Some(347				jrsonnet_parser::parse(348					&code,349					&ParserSettings {350						source: file_name.clone(),351					},352				)353				.map(Rc::new)354				.map_err(|e| ImportSyntaxError {355					path: file_name.clone(),356					error: Box::new(e),357				})?,358			);359		}360		let parsed = file.parsed.as_ref().expect("just set").clone();361		if file.evaluating {362			bail!(InfiniteRecursionDetected)363		}364		file.evaluating = true;365		// Dropping file cache guard here, as evaluation may use this map too366		drop(file_cache);367		let res = evaluate(self.create_default_context(file_name), &parsed);368369		let mut file_cache = self.file_cache();370		let mut file = file_cache.entry(path.clone());371372		let Entry::Occupied(file) = &mut file else {373			unreachable!("this file was just here")374		};375		let file = file.get_mut();376		file.evaluating = false;377		match res {378			Ok(v) => {379				file.evaluated = Some(v.clone());380				Ok(v)381			}382			Err(e) => Err(e),383		}384	}385386	/// Has same semantics as `import 'path'` called from `from` file387	pub fn import_from(&self, from: &SourcePath, path: impl AsPathLike) -> Result<Val> {388		let resolved = self.resolve_from(from, &path)?;389		self.import_resolved(resolved)390	}391	pub fn import(&self, path: impl AsPathLike) -> Result<Val> {392		let resolved = self.resolve_from_default(&path)?;393		self.import_resolved(resolved)394	}395396	/// Creates context with all passed global variables397	pub fn create_default_context(&self, source: Source) -> Context {398		self.context_initializer().initialize(source)399	}400401	/// Creates context with all passed global variables, calling custom modifier402	pub fn create_default_context_with(403		&self,404		source: Source,405		context_initializer: impl ContextInitializer,406	) -> Context {407		let default_initializer = self.context_initializer();408		let mut builder = ContextBuilder::with_capacity(409			default_initializer.reserve_vars() + context_initializer.reserve_vars(),410		);411		default_initializer.populate(source.clone(), &mut builder);412		context_initializer.populate(source, &mut builder);413414		builder.build()415	}416}417418/// Internals419impl State {420	fn file_cache(&self) -> RefMut<'_, FxHashMap<SourcePath, FileData>> {421		self.0.file_cache.borrow_mut()422	}423}424/// Executes code creating a new stack frame, to be replaced with try{}425pub fn in_frame<T>(426	e: CallLocation<'_>,427	frame_desc: impl FnOnce() -> String,428	f: impl FnOnce() -> Result<T>,429) -> Result<T> {430	let _guard = check_depth()?;431432	f().with_description_src(e, frame_desc)433}434435/// Executes code creating a new stack frame, to be replaced with try{}436pub fn in_description_frame<T>(437	frame_desc: impl FnOnce() -> String,438	f: impl FnOnce() -> Result<T>,439) -> Result<T> {440	let _guard = check_depth()?;441442	f().with_description(frame_desc)443}444445#[derive(Trace)]446pub struct InitialUnderscore(pub Thunk<Val>);447impl ContextInitializer for InitialUnderscore {448	fn populate(&self, _for_file: Source, builder: &mut ContextBuilder) {449		builder.bind("_", self.0.clone());450	}451452	fn as_any(&self) -> &dyn Any {453		self454	}455}456457/// Raw methods evaluate passed values but don't perform TLA execution458impl State {459	/// Parses and evaluates the given snippet460	pub fn evaluate_snippet(&self, name: impl Into<IStr>, code: impl Into<IStr>) -> Result<Val> {461		let code = code.into();462		let source = Source::new_virtual(name.into(), code.clone());463		let parsed = jrsonnet_parser::parse(464			&code,465			&ParserSettings {466				source: source.clone(),467			},468		)469		.map_err(|e| ImportSyntaxError {470			path: source.clone(),471			error: Box::new(e),472		})?;473		evaluate(self.create_default_context(source), &parsed)474	}475	/// Parses and evaluates the given snippet with custom context modifier476	pub fn evaluate_snippet_with(477		&self,478		name: impl Into<IStr>,479		code: impl Into<IStr>,480		context_initializer: impl ContextInitializer,481	) -> Result<Val> {482		let code = code.into();483		let source = Source::new_virtual(name.into(), code.clone());484		let parsed = jrsonnet_parser::parse(485			&code,486			&ParserSettings {487				source: source.clone(),488			},489		)490		.map_err(|e| ImportSyntaxError {491			path: source.clone(),492			error: Box::new(e),493		})?;494		evaluate(495			self.create_default_context_with(source, context_initializer),496			&parsed,497		)498	}499}500501/// Settings utilities502impl State {503	// Only panics in case of [`ImportResolver`] contract violation504	#[allow(clippy::missing_panics_doc)]505	pub fn resolve_from(&self, from: &SourcePath, path: &dyn AsPathLike) -> Result<SourcePath> {506		self.import_resolver().resolve_from(from, path)507	}508	#[allow(clippy::missing_panics_doc)]509	pub fn resolve_from_default(&self, path: &dyn AsPathLike) -> Result<SourcePath> {510		self.import_resolver().resolve_from_default(path)511	}512	pub fn import_resolver(&self) -> &dyn ImportResolver {513		&*self.0.import_resolver514	}515	pub fn context_initializer(&self) -> &dyn ContextInitializer {516		&*self.0.context_initializer.0517	}518}519520impl State {521	pub fn builder() -> StateBuilder {522		StateBuilder::default()523	}524}525526impl Default for State {527	fn default() -> Self {528		Self::builder().build()529	}530}531532#[derive(Default)]533pub struct StateBuilder {534	import_resolver: Option<Rc<dyn ImportResolver>>,535	context_initializer: Option<CcContextInitializer>,536}537impl StateBuilder {538	pub fn import_resolver(&mut self, import_resolver: impl ImportResolver) -> &mut Self {539		let _ = self.import_resolver.insert(Rc::new(import_resolver));540		self541	}542	pub fn context_initializer(543		&mut self,544		context_initializer: impl ContextInitializer,545	) -> &mut Self {546		let _ = self547			.context_initializer548			.insert(CcContextInitializer::new(context_initializer));549		self550	}551	pub fn build(mut self) -> State {552		State(Cc::new(EvaluationStateInternals {553			file_cache: RefCell::new(FxHashMap::new()),554			context_initializer: self555				.context_initializer556				.take()557				.unwrap_or_else(|| CcContextInitializer::new(())),558			import_resolver: self559				.import_resolver560				.take()561				.unwrap_or_else(|| Rc::new(DummyImportResolver)),562		}))563	}564}