git.delta.rocks / jrsonnet / refs/commits / 1d4b842070e4

1use crate::{2	error::Error::*, future_wrapper, map::LayeredHashMap, rc_fn_helper, resolved_lazy_val,3	LazyBinding, LazyVal, ObjValue, Result, Val,4};5use std::{6	cell::RefCell,7	collections::HashMap,8	fmt::Debug,9	rc::{Rc, Weak},10};1112rc_fn_helper!(13	ContextCreator,14	context_creator,15	dyn Fn(Option<ObjValue>, Option<ObjValue>) -> Result<Context>16);1718future_wrapper!(Context, FutureContext);1920struct ContextInternals {21	dollar: Option<ObjValue>,22	this: Option<ObjValue>,23	super_obj: Option<ObjValue>,24	bindings: LayeredHashMap<Rc<str>, LazyVal>,25}26impl Debug for ContextInternals {27	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {28		f.debug_struct("Context")29			.field("this", &self.this.as_ref().map(|e| Rc::as_ptr(&e.0)))30			.field("bindings", &self.bindings)31			.finish()32	}33}3435#[derive(Debug, Clone)]36pub struct Context(Rc<ContextInternals>);37impl Context {38	pub fn new_future() -> FutureContext {39		FutureContext(Rc::new(RefCell::new(None)))40	}4142	pub fn dollar(&self) -> &Option<ObjValue> {43		&self.0.dollar44	}4546	pub fn this(&self) -> &Option<ObjValue> {47		&self.0.this48	}4950	pub fn super_obj(&self) -> &Option<ObjValue> {51		&self.0.super_obj52	}5354	pub fn new() -> Context {55		Context(Rc::new(ContextInternals {56			dollar: None,57			this: None,58			super_obj: None,59			bindings: LayeredHashMap::default(),60		}))61	}6263	pub fn binding(&self, name: Rc<str>) -> Result<LazyVal> {64		Ok(self65			.066			.bindings67			.get(&name)68			.cloned()69			.ok_or_else(|| UnknownVariable(name))?)70	}71	pub fn into_future(self, ctx: FutureContext) -> Context {72		{73			ctx.0.borrow_mut().replace(self);74		}75		ctx.unwrap()76	}7778	pub fn with_var(self, name: Rc<str>, value: Val) -> Context {79		let mut new_bindings = HashMap::with_capacity(1);80		new_bindings.insert(name, resolved_lazy_val!(value));81		self.extend(new_bindings, None, None, None)82	}8384	pub fn extend(85		self,86		new_bindings: HashMap<Rc<str>, LazyVal>,87		new_dollar: Option<ObjValue>,88		new_this: Option<ObjValue>,89		new_super_obj: Option<ObjValue>,90	) -> Context {91		match Rc::try_unwrap(self.0) {92			Ok(mut ctx) => {93				// Extended context aren't used by anything else, we can freely mutate it without cloning94				if let Some(dollar) = new_dollar {95					ctx.dollar = Some(dollar);96				}97				if let Some(this) = new_this {98					ctx.this = Some(this);99				}100				if let Some(super_obj) = new_super_obj {101					ctx.super_obj = Some(super_obj);102				}103				if !new_bindings.is_empty() {104					ctx.bindings = ctx.bindings.extend(new_bindings);105				}106				Context(Rc::new(ctx))107			}108			Err(ctx) => {109				let dollar = new_dollar.or_else(|| ctx.dollar.clone());110				let this = new_this.or_else(|| ctx.this.clone());111				let super_obj = new_super_obj.or_else(|| ctx.super_obj.clone());112				let bindings = if new_bindings.is_empty() {113					ctx.bindings.clone()114				} else {115					ctx.bindings.clone().extend(new_bindings)116				};117				Context(Rc::new(ContextInternals {118					dollar,119					this,120					super_obj,121					bindings,122				}))123			}124		}125	}126	pub fn extend_unbound(127		self,128		new_bindings: HashMap<Rc<str>, LazyBinding>,129		new_dollar: Option<ObjValue>,130		new_this: Option<ObjValue>,131		new_super_obj: Option<ObjValue>,132	) -> Result<Context> {133		let this = new_this.or_else(|| self.0.this.clone());134		let super_obj = new_super_obj.or_else(|| self.0.super_obj.clone());135		let mut new = HashMap::with_capacity(new_bindings.len());136		for (k, v) in new_bindings.into_iter() {137			new.insert(k, v.evaluate(this.clone(), super_obj.clone())?);138		}139		Ok(self.extend(new, new_dollar, this, super_obj))140	}141	pub fn into_weak(self) -> WeakContext {142		WeakContext(Rc::downgrade(&self.0))143	}144}145146impl Default for Context {147	fn default() -> Self {148		Self::new()149	}150}151152impl PartialEq for Context {153	fn eq(&self, other: &Self) -> bool {154		Rc::ptr_eq(&self.0, &other.0)155	}156}157158#[derive(Debug, Clone)]159pub struct WeakContext(Weak<ContextInternals>);160impl WeakContext {161	pub fn upgrade(&self) -> Context {162		Context(self.0.upgrade().expect("context is removed"))163	}164}165impl PartialEq for WeakContext {166	fn eq(&self, other: &Self) -> bool {167		self.0.ptr_eq(&other.0)168	}169}