[core][rewriter] dpsc: add rest cleaning rewrites

Author: velzie

rewriter/js/src/cfg.rs

@@ -19,6 +19,7 @@ pub struct Config {
 	pub wrapfn: String,
 	pub wrappropertybase: String,
 	pub wrappropertyfn: String,
+	pub cleanrestfn: String,
 	pub importfn: String,
 	pub rewritefn: String,
 	pub setrealmfn: String,

rewriter/js/src/changes.rs

@@ -44,6 +44,10 @@ pub enum JsChangeType<'alloc: 'data, 'data> {
 		ident: Atom<'data>,
 	},
 
+	WrapObjectAssignmentLeft {
+		restids: Vec<Atom<'data>>,
+	},
+
 	/// insert `${cfg.setrealmfn}({}).`
 	SetRealmFn,
 	/// insert `$scramerr(ident);`
@@ -128,7 +132,14 @@ impl<'alloc: 'data, 'data> Transform<'data> for JsChange<'alloc, 'data> {
 			Ty::RebindProperty { ident } => {
 				LL::replace(transforms![&cfg.wrappropertybase, ident, ":", ident])
 			}
-
+			Ty::WrapObjectAssignmentLeft { restids } => {
+				let mut steps = String::new();
+				for id in restids {
+					steps.push_str(&format!("{}({}),", &cfg.cleanrestfn, id.as_str()));
+				}
+				let steps: &'static str = Box::leak(steps.into_boxed_str());
+				LL::insert(transforms!["((t)=>(", &steps, "t))("])
+			}
 			Ty::SetRealmFn => LL::insert(transforms![&cfg.setrealmfn, "({})."]),
 			Ty::ScramErrFn { ident } => LL::insert(transforms!["$scramerr(", ident, ");"]),
 			Ty::ScramitizeFn => LL::insert(transforms![" $scramitize("]),

rewriter/js/src/rewrite.rs

@@ -37,6 +37,10 @@ pub(crate) enum RewriteType<'alloc: 'data, 'data> {
 		ident: Atom<'data>,
 	},
 
+	WrapObjectAssignment {
+		restids: Vec<Atom<'data>>,
+	},
+
 	/// `cfg.wrapprop({})`
 	WrapProperty,
 
@@ -119,6 +123,16 @@ impl<'alloc: 'data, 'data> RewriteType<'alloc, 'data> {
 				change!(span!(start), WrapPropertyLeft),
 				change!(span!(end), WrapPropertyRight),
 			],
+			Self::WrapObjectAssignment { restids } => smallvec![
+				change!(span!(start), WrapObjectAssignmentLeft { restids }),
+				change!(
+					span!(end),
+					ClosingParen {
+						semi: false,
+						replace: false
+					}
+				)
+			],
 			Self::SetRealmFn => smallvec![change!(span, SetRealmFn)],
 			Self::ImportFn => smallvec![change!(span, ImportFn)],
 			Self::MetaFn => smallvec![change!(span, MetaFn)],

rewriter/js/src/visitor.rs

@@ -4,13 +4,13 @@ use oxc::{
 	allocator::{Allocator, StringBuilder},
 	ast::ast::{
 		AssignmentExpression, AssignmentTarget, AssignmentTargetMaybeDefault,
-		AssignmentTargetProperty, BindingPattern, BindingPatternKind, BindingProperty,
-		CallExpression, ComputedMemberExpression, DebuggerStatement, ExportAllDeclaration,
-		ExportNamedDeclaration, Expression, FunctionBody, IdentifierReference, ImportDeclaration,
-		ImportExpression, MemberExpression, MetaProperty, NewExpression, ObjectAssignmentTarget,
-		ObjectExpression, ObjectPattern, ObjectPropertyKind, PrivateIdentifier, PropertyKey,
-		ReturnStatement, SimpleAssignmentTarget, StringLiteral, ThisExpression, UnaryExpression,
-		UnaryOperator, UpdateExpression,
+		AssignmentTargetProperty, AssignmentTargetPropertyIdentifier, BindingPattern,
+		BindingPatternKind, BindingProperty, CallExpression, ComputedMemberExpression,
+		DebuggerStatement, ExportAllDeclaration, ExportNamedDeclaration, Expression, FunctionBody,
+		IdentifierReference, ImportDeclaration, ImportExpression, MemberExpression, MetaProperty,
+		NewExpression, ObjectAssignmentTarget, ObjectExpression, ObjectPattern, ObjectPropertyKind,
+		PrivateIdentifier, PropertyKey, ReturnStatement, SimpleAssignmentTarget, StringLiteral,
+		ThisExpression, UnaryExpression, UnaryOperator, UpdateExpression,
 	},
 	ast_visit::{Visit, walk},
 	span::{Atom, GetSpan, Span},
@@ -104,10 +104,21 @@ where
 		}
 	}
 
-	fn recurse_object_assignment_target(&mut self, s: &ObjectAssignmentTarget<'data>) {
-		if s.rest.is_some() {
-			// infeasible to rewrite :(
-			eprintln!("cannot rewrite rest parameters");
+	fn recurse_object_assignment_target(
+		&mut self,
+		s: &ObjectAssignmentTarget<'data>,
+		restids: &mut Vec<Atom<'data>>,
+	) {
+		if let Some(r) = &s.rest {
+			// { ...rest } = self;
+			match &r.target {
+				AssignmentTarget::AssignmentTargetIdentifier(i) => {
+					// keep track of the name so we can clean it later
+					// i don't really care about the rest being `location` here, if someone wants to redirect to `https://proxy.com/[Object object]` they can
+					restids.push(i.name);
+				}
+				_ => panic!("what?"),
+			}
 			return;
 		}
 		for prop in &s.properties {
@@ -168,7 +179,7 @@ where
 							walk::walk_expression(self, &d.init);
 						}
 						AssignmentTargetMaybeDefault::ObjectAssignmentTarget(p) => {
-							self.recurse_object_assignment_target(p);
+							self.recurse_object_assignment_target(p, restids);
 						}
 						_ => {}
 					}
@@ -487,7 +498,13 @@ where
 				walk::walk_expression(self, &s.expression);
 			}
 			AssignmentTarget::ObjectAssignmentTarget(o) => {
-				self.recurse_object_assignment_target(o);
+				let mut restids: Vec<Atom<'data>> = Vec::new();
+				self.recurse_object_assignment_target(o, &mut restids);
+
+				if restids.len() > 0 {
+					self.jschanges
+						.add(rewrite!(it.span, WrapObjectAssignment { restids }));
+				}
 				return;
 			}
 			_ => {}

rewriter/native/src/main.rs

@@ -29,6 +29,8 @@ pub struct RewriterOptions {
 	wrappropertybase: String,
 	#[clap(long, default_value = "$prop")]
 	wrappropertyfn: String,
+	#[clap(long, default_value = "$clean")]
+	cleanrestfn: String,
 	#[clap(long, default_value = "$import")]
 	importfn: String,
 	#[clap(long, default_value = "$rewrite")]

rewriter/native/src/rewriter.rs

@@ -54,6 +54,7 @@ impl NativeRewriter {
 				wrapfn: cfg.wrapfn.clone(),
 				wrappropertybase: cfg.wrappropertybase.clone(),
 				wrappropertyfn: cfg.wrappropertyfn.clone(),
+				cleanrestfn: cfg.cleanrestfn.clone(),
 				importfn: cfg.importfn.clone(),
 				rewritefn: cfg.rewritefn.clone(),
 				metafn: cfg.metafn.clone(),

rewriter/wasm/src/jsr.rs

@@ -51,6 +51,7 @@ fn get_config(scramjet: &Object) -> Result<Config> {
 
 		wrappropertybase: get_str(globals, "wrappropertybase")?,
 		wrappropertyfn: get_str(globals, "wrappropertyfn")?,
+		cleanrestfn: get_str(globals, "cleanrestfn")?,
 		wrapfn: get_str(globals, "wrapfn")?,
 		importfn: get_str(globals, "importfn")?,
 		rewritefn: get_str(globals, "rewritefn")?,

src/client/shared/wrap.ts

@@ -66,7 +66,14 @@ export default function (client: ScramjetClient, self: typeof globalThis) {
 		configurable: false,
 		enumerable: false,
 	});
-	console.log(config.globals.wrappropertybase);
+	Object.defineProperty(self, config.globals.cleanrestfn, {
+		value: function (obj) {
+			// TODO
+		},
+		writable: false,
+		configurable: false,
+		enumerable: false,
+	});
 
 	Object.defineProperty(
 		self.Object.prototype,

src/controller/index.ts

@@ -20,6 +20,7 @@ export class ScramjetController {
 				wrapfn: "$scramjet$wrap",
 				wrappropertybase: "$scramjet__",
 				wrappropertyfn: "$scramjet$prop",
+				cleanrestfn: "$scramjet$clean",
 				trysetfn: "$scramjet$tryset",
 				importfn: "$scramjet$import",
 				rewritefn: "$scramjet$rewrite",

src/types.ts

@@ -22,6 +22,7 @@ export interface ScramjetConfig {
 		wrapfn: string;
 		wrappropertybase: string;
 		wrappropertyfn: string;
+		cleanrestfn: string;
 		trysetfn: string;
 		importfn: string;
 		rewritefn: string;