git.delta.rocks / jrsonnet / refs/commits / b5434962bef6

difftreelog

feat lazy evaluation of function default params

Yaroslav Bolyukin2021-08-20parent: #d512ff6.patch.diff
in: master
Fixes #59

7 files changed

modifiedcrates/jrsonnet-evaluator/src/ctx.rsdiffbeforeafterboth
73 .cloned()73 .cloned()
74 .ok_or(VariableIsNotDefined(name))?)74 .ok_or(VariableIsNotDefined(name))?)
75 }75 }
76 pub fn contains_binding(&self, name: IStr) -> bool {
77 self.0.bindings.contains_key(&name)
78 }
76 pub fn into_future(self, ctx: FutureWrapper<Self>) -> Self {79 pub fn into_future(self, ctx: FutureWrapper<Self>) -> Self {
77 {80 {
78 ctx.0.borrow_mut().replace(self);81 ctx.0.borrow_mut().replace(self);
modifiedcrates/jrsonnet-evaluator/src/error.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/error.rs
+++ b/crates/jrsonnet-evaluator/src/error.rs
@@ -56,7 +56,7 @@
 	BindingParameterASecondTime(IStr),
 	#[error("too many args, function has {0}")]
 	TooManyArgsFunctionHas(usize),
-	#[error("founction argument is not passed: {0}")]
+	#[error("function argument is not passed: {0}")]
 	FunctionParameterNotBoundInCall(IStr),
 
 	#[error("external variable is not defined: {0}")]
modifiedcrates/jrsonnet-evaluator/src/function.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/function.rs
+++ b/crates/jrsonnet-evaluator/src/function.rs
@@ -1,4 +1,7 @@
-use crate::{error::Error::*, evaluate, throw, Context, LazyVal, LazyValValue, Result, Val};
+use crate::{
+	error::Error::*, evaluate, evaluate_named, throw, Context, FutureWrapper, LazyVal,
+	LazyValValue, Result, Val,
+};
 use jrsonnet_gc::Trace;
 use jrsonnet_interner::IStr;
 use jrsonnet_parser::{ArgsDesc, LocExpr, ParamsDesc};
@@ -8,6 +11,18 @@
 const NO_DEFAULT_CONTEXT: &str =
 	"no default context set for call with defined default parameter value";
 
+#[derive(Trace)]
+#[trivially_drop]
+struct EvaluateLazyVal {
+	context: Context,
+	expr: LocExpr,
+}
+impl LazyValValue for EvaluateLazyVal {
+	fn get(self: Box<Self>) -> Result<Val> {
+		evaluate(self.context, &self.expr)
+	}
+}
+
 /// Creates correct [context](Context) for function body evaluation returning error on invalid call.
 ///
 /// ## Parameters
@@ -18,64 +33,119 @@
 /// * `tailstrict`: if set to `true` function arguments are eagerly executed, otherwise - lazily
 pub fn parse_function_call(
 	ctx: Context,
-	body_ctx: Option<Context>,
+	body_ctx: Context,
 	params: &ParamsDesc,
 	args: &ArgsDesc,
 	tailstrict: bool,
 ) -> Result<Context> {
-	let mut out = HashMap::with_capacity_and_hasher(params.len(), BuildHasherDefault::default());
-	let mut positioned_args = vec![None; params.0.len()];
-	for (id, arg) in args.iter().enumerate() {
-		let idx = if let Some(name) = &arg.0 {
-			params
-				.iter()
-				.position(|p| *p.0 == *name)
-				.ok_or_else(|| UnknownFunctionParameter(name.clone()))?
-		} else {
-			id
-		};
+	let mut passed_args =
+		HashMap::with_capacity_and_hasher(params.len(), BuildHasherDefault::default());
+	if args.unnamed.len() > params.len() {
+		throw!(TooManyArgsFunctionHas(params.len()))
+	}
+
+	let mut filled_args = 0;
 
-		if idx >= params.len() {
-			throw!(TooManyArgsFunctionHas(params.len()));
+	for (id, arg) in args.unnamed.iter().enumerate() {
+		let name = params[id].0.clone();
+		passed_args.insert(
+			name,
+			if tailstrict {
+				LazyVal::new_resolved(evaluate(ctx.clone(), arg)?)
+			} else {
+				LazyVal::new(Box::new(EvaluateLazyVal {
+					context: ctx.clone(),
+					expr: arg.clone(),
+				}))
+			},
+		);
+		filled_args += 1;
+	}
+
+	for (name, value) in args.named.iter() {
+		// FIXME: O(n) for arg existence check
+		if !params.iter().any(|p| &p.0 == name) {
+			throw!(UnknownFunctionParameter((name as &str).to_owned()));
 		}
-		if positioned_args[idx].is_some() {
-			throw!(BindingParameterASecondTime(params[idx].0.clone()));
+		if passed_args
+			.insert(
+				name.clone(),
+				if tailstrict {
+					LazyVal::new_resolved(evaluate(ctx.clone(), value)?)
+				} else {
+					LazyVal::new(Box::new(EvaluateLazyVal {
+						context: ctx.clone(),
+						expr: value.clone(),
+					}))
+				},
+			)
+			.is_some()
+		{
+			throw!(BindingParameterASecondTime(name.clone()));
 		}
-		positioned_args[idx] = Some(arg.1.clone());
+		filled_args += 1;
 	}
-	// Fill defaults
-	for (id, p) in params.iter().enumerate() {
-		let (ctx, expr) = if let Some(arg) = &positioned_args[id] {
-			(ctx.clone(), arg)
-		} else if let Some(default) = &p.1 {
-			(body_ctx.clone().expect(NO_DEFAULT_CONTEXT), default)
-		} else {
-			throw!(FunctionParameterNotBoundInCall(p.0.clone()));
-		};
-		let val = if tailstrict {
-			LazyVal::new_resolved(evaluate(ctx, expr)?)
-		} else {
+
+	if filled_args < params.len() {
+		// Some args are unset, but maybe we have defaults for them
+		// Default values should be created in newly created context
+		let future_context = FutureWrapper::<Context>::new();
+		let mut defaults = HashMap::with_capacity_and_hasher(
+			params.len() - filled_args,
+			BuildHasherDefault::default(),
+		);
+
+		for param in params.iter().filter(|p| p.1.is_some()) {
+			if passed_args.contains_key(&param.0.clone()) {
+				continue;
+			}
 			#[derive(Trace)]
 			#[trivially_drop]
-			struct EvaluateLazyVal {
-				context: Context,
-				expr: LocExpr,
+			struct LazyNamedBinding {
+				future_context: FutureWrapper<Context>,
+				name: IStr,
+				value: LocExpr,
 			}
-			impl LazyValValue for EvaluateLazyVal {
+			impl LazyValValue for LazyNamedBinding {
 				fn get(self: Box<Self>) -> Result<Val> {
-					evaluate(self.context, &self.expr)
+					evaluate_named(self.future_context.unwrap(), &self.value, self.name)
 				}
 			}
+			LazyVal::new(Box::new(LazyNamedBinding {
+				future_context: future_context.clone(),
+				name: param.0.clone(),
+				value: param.1.clone().unwrap(),
+			}));
 
-			LazyVal::new(Box::new(EvaluateLazyVal {
-				context: ctx.clone(),
-				expr: expr.clone(),
-			}))
-		};
-		out.insert(p.0.clone(), val);
-	}
+			defaults.insert(
+				param.0.clone(),
+				LazyVal::new(Box::new(LazyNamedBinding {
+					future_context: future_context.clone(),
+					name: param.0.clone(),
+					value: param.1.clone().unwrap(),
+				})),
+			);
+			filled_args += 1;
+		}
+
+		// Some args still wasn't filled
+		if filled_args != params.len() {
+			for param in params.iter().skip(args.unnamed.len()) {
+				if !args.named.iter().any(|a| a.0 == param.0) {
+					throw!(FunctionParameterNotBoundInCall(param.0.clone()));
+				}
+			}
+			unreachable!();
+		}
 
-	Ok(body_ctx.unwrap_or(ctx).extend(out, None, None, None))
+		Ok(body_ctx
+			.extend(passed_args, None, None, None)
+			.extend_bound(defaults)
+			.into_future(future_context))
+	} else {
+		let body_ctx = body_ctx.extend(passed_args, None, None, None);
+		Ok(body_ctx)
+	}
 }
 
 pub fn parse_function_call_map(
@@ -176,21 +246,25 @@
 		use $crate::{error::Error::*, throw, evaluate, push_stack_frame, typed::CheckType};
 
 		let args = $args;
-		if args.len() > $total_args {
+		if args.unnamed.len() + args.named.len() > $total_args {
 			throw!(TooManyArgsFunctionHas($total_args));
 		}
 		$(
-			if args.len() <= $id {
+			if args.unnamed.len() + args.named.len() <= $id {
 				throw!(FunctionParameterNotBoundInCall(stringify!($name).into()));
 			}
-			let $name = &args[$id];
-			if $name.0.is_some() {
-				if $name.0.as_ref().unwrap() != stringify!($name) {
+			// Is named
+			let $name = if $id >= $args.unnamed.len() {
+				let named = &args.named[$id - $args.unnamed.len()];
+				if &named.0 != stringify!($name) {
 					throw!(IntrinsicArgumentReorderingIsNotSupportedYet);
 				}
-			}
+				&named.1
+			} else {
+				&$args.unnamed[$id]
+			};
 			let $name = push_stack_frame(None, || format!("evaluating argument"), || {
-				let value = evaluate($ctx.clone(), &$name.1)?;
+				let value = evaluate($ctx.clone(), &$name)?;
 				$ty.check(&value)?;
 				Ok(value)
 			})?;
modifiedcrates/jrsonnet-evaluator/src/map.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/map.rs
+++ b/crates/jrsonnet-evaluator/src/map.rs
@@ -29,6 +29,16 @@
 			.get(key)
 			.or_else(|| self.0.parent.as_ref().and_then(|p| p.get(key)))
 	}
+
+	pub fn contains_key(&self, key: &IStr) -> bool {
+		(self.0).current.contains_key(key)
+			|| self
+				.0
+				.parent
+				.as_ref()
+				.map(|p| p.contains_key(key))
+				.unwrap_or(false)
+	}
 }
 
 impl Clone for LayeredHashMap {
modifiedcrates/jrsonnet-evaluator/src/val.rsdiffbeforeafterboth
--- a/crates/jrsonnet-evaluator/src/val.rs
+++ b/crates/jrsonnet-evaluator/src/val.rs
@@ -11,7 +11,7 @@
 };
 use jrsonnet_gc::{Gc, GcCell, Trace};
 use jrsonnet_interner::IStr;
-use jrsonnet_parser::{el, Arg, ArgsDesc, Expr, ExprLocation, LiteralType, LocExpr, ParamsDesc};
+use jrsonnet_parser::{el, ArgsDesc, Expr, ExprLocation, LiteralType, LocExpr, ParamsDesc};
 use jrsonnet_types::ValType;
 use std::{collections::HashMap, fmt::Debug, rc::Rc};
 
@@ -127,7 +127,7 @@
 			Self::Normal(func) => {
 				let ctx = parse_function_call(
 					call_ctx,
-					Some(func.ctx.clone()),
+					func.ctx.clone(),
 					&func.params,
 					args,
 					tailstrict,
@@ -136,7 +136,8 @@
 			}
 			Self::Intrinsic(name) => call_builtin(call_ctx, loc, name, args),
 			Self::NativeExt(_name, handler) => {
-				let args = parse_function_call(call_ctx, None, &handler.params, args, true)?;
+				let args =
+					parse_function_call(call_ctx, Context::new(), &handler.params, args, true)?;
 				let mut out_args = Vec::with_capacity(handler.params.len());
 				for p in handler.params.0.iter() {
 					out_args.push(args.binding(p.0.clone())?.evaluate()?);
@@ -554,17 +555,17 @@
 						el!(Expr::Var("std".into())),
 						el!(Expr::Str("manifestYamlDoc".into()))
 					)),
-					ArgsDesc(vec![
-						Arg(None, el!(Expr::Var("__tmp__to_json__".into()))),
-						Arg(
-							None,
+					ArgsDesc::new(
+						vec![
+							el!(Expr::Var("__tmp__to_json__".into())),
 							el!(Expr::Literal(if padding != 0 {
 								LiteralType::True
 							} else {
 								LiteralType::False
-							}))
-						)
-					]),
+							})),
+						],
+						vec![]
+					),
 					false
 				)),
 			)?
modifiedcrates/jrsonnet-parser/src/expr.rsdiffbeforeafterboth
--- a/crates/jrsonnet-parser/src/expr.rs
+++ b/crates/jrsonnet-parser/src/expr.rs
@@ -194,18 +194,13 @@
 #[cfg_attr(feature = "deserialize", derive(Deserialize))]
 #[derive(Debug, PartialEq, Trace)]
 #[trivially_drop]
-pub struct Arg(pub Option<String>, pub LocExpr);
-
-#[cfg_attr(feature = "serialize", derive(Serialize))]
-#[cfg_attr(feature = "deserialize", derive(Deserialize))]
-#[derive(Debug, PartialEq, Trace)]
-#[trivially_drop]
-pub struct ArgsDesc(pub Vec<Arg>);
-
-impl Deref for ArgsDesc {
-	type Target = Vec<Arg>;
-	fn deref(&self) -> &Self::Target {
-		&self.0
+pub struct ArgsDesc {
+	pub unnamed: Vec<LocExpr>,
+	pub named: Vec<(IStr, LocExpr)>,
+}
+impl ArgsDesc {
+	pub fn new(unnamed: Vec<LocExpr>, named: Vec<(IStr, LocExpr)>) -> Self {
+		Self { unnamed, named }
 	}
 }
 
modifiedcrates/jrsonnet-parser/src/lib.rsdiffbeforeafterboth
--- a/crates/jrsonnet-parser/src/lib.rs
+++ b/crates/jrsonnet-parser/src/lib.rs
@@ -7,6 +7,7 @@
 };
 mod expr;
 pub use expr::*;
+pub use jrsonnet_interner::IStr;
 pub use peg;
 
 pub struct ParserSettings {
@@ -70,19 +71,29 @@
 			}
 			/ { expr::ParamsDesc(Rc::new(Vec::new())) }
 
-		pub rule arg(s: &ParserSettings) -> expr::Arg
-			= name:$(id()) _ "=" _ expr:expr(s) {expr::Arg(Some(name.into()), expr)}
-			/ expr:expr(s) {expr::Arg(None, expr)}
+		pub rule arg(s: &ParserSettings) -> (Option<IStr>, LocExpr)
+			= quiet! { name:(s:$(id()) _ "=" _ {s})? expr:expr(s) {(name.map(Into::into), expr)} }
+			/ expected!("<argument>")
+
 		pub rule args(s: &ParserSettings) -> expr::ArgsDesc
-			= args:arg(s) ** comma() comma()? {
+			= args:arg(s)**comma() comma()? {?
+				let unnamed_count = args.iter().take_while(|(n, _)| n.is_none()).count();
+				let mut unnamed = Vec::with_capacity(unnamed_count);
+				let mut named = Vec::with_capacity(args.len() - unnamed_count);
 				let mut named_started = false;
-				for arg in &args {
-					named_started = named_started || arg.0.is_some();
-					assert_eq!(named_started, arg.0.is_some(), "named args should be used after all positionals");
+				for (name, value) in args {
+					if let Some(name) = name {
+						named_started = true;
+						named.push((name, value));
+					} else {
+						if named_started {
+							return Err("<named argument>")
+						}
+						unnamed.push(value);
+					}
 				}
-				expr::ArgsDesc(args)
+				Ok(expr::ArgsDesc::new(unnamed, named))
 			}
-			/ { expr::ArgsDesc(Vec::new()) }
 
 		pub rule bind(s: &ParserSettings) -> expr::BindSpec
 			= name:$(id()) _ "=" _ expr:expr(s) {expr::BindSpec{name:name.into(), params: None, value: expr}}
@@ -493,7 +504,7 @@
 			el!(ArrComp(
 				el!(Apply(
 					el!(Index(el!(Var("std".into())), el!(Str("deepJoin".into())))),
-					ArgsDesc(vec![Arg(None, el!(Var("x".into())))]),
+					ArgsDesc::new(vec![el!(Var("x".into()))], vec![]),
 					false,
 				)),
 				vec![CompSpec::ForSpec(ForSpecData(