fix(ts): erase a called function's late-bound regions before asking what its inputs hold

quest/m0/README.md

@@ -7,4 +7,4 @@ Urgent fixes to anything a consumer already depends on.
 ## Required
 
 - [Checks at moq's cost](/quest/m0/checks/README.md) - `just ci` selects by the diff, builds warm, and runs the differential optimized, with a nightly full `just gate`
-- [Translating moq-net panics on a dyn Buf](/quest/m0/ts-moq-dyn-panic.md) - `just ts moq` and `just ts bench` translate moq-net at the pin again
+- [Gate moq-net's translation](/quest/m0/ts-moq-gate.md) - `just ci` translates moq-net at the pin, so a change that breaks it fails in the queue

quest/m0/ts-moq-gate.md

@@ -0,0 +1,22 @@
+# [S] Gate moq-net's translation
+
+## Goal
+
+A change that breaks moq-net's translation fails in the merge queue, not the next nightly:
+`just ci` for a `ts` change translates moq-net at the pin and type-checks it, as
+`just ts moq` does. Today only `nightly.yml` runs `just ts moq`, so
+[moq-dev/rust2#519](https://github.com/moq-dev/rust2/pull/519) landed a panic on moq-net
+that a bench run found hours later.
+
+## Plan
+
+`just ts check` already checks out the pin for the bench's type-check, so what this adds is
+building moq-net's dependencies through the driver and translating it. Measure that in CPU,
+cold and warm, against [the checks budget](/quest/m0/checks/README.md) before adding it;
+if it costs too much, consider running it only for changes under `ts/src` or `ts/runtime`.
+
+Public API: none.
+
+## Related
+
+- [Checks at moq's cost](/quest/m0/checks/README.md) - the gate's CPU budget this spends from

ts/fixtures/stock/expected/buf.Leased.ts

@@ -1,10 +1,11 @@
 // Generated by rust2-ts. Do not edit.
 
 import * as rt from "./rt.ts";
+import type * as Buf from "./bytes/buf/buf_impl.Buf.ts";
 import type * as TryGetError from "./bytes.TryGetError.ts";
 
 /** A buffer of the crate's own over `Buf`, as moq's transports lend a stream's chunks. */
 export type Leased =
-	| { pieces$Leased: () => rt.usize; remaining$Buf: () => rt.usize; chunk$Buf: () => rt.ByteSlice; advance$Buf: (a0: rt.usize) => void; hasRemaining$Buf: () => boolean; copyToSlice$Buf: (a0: rt.ByteSlice) => void; getU8$Buf: () => rt.u8; getI8$Buf: () => rt.i8; getU16$Buf: () => rt.u16; getU16Le$Buf: () => rt.u16; getU16Ne$Buf: () => rt.u16; getI16$Buf: () => rt.i16; getI16Le$Buf: () => rt.i16; getI16Ne$Buf: () => rt.i16; getU32$Buf: () => rt.u32; getU32Le$Buf: () => rt.u32; getU32Ne$Buf: () => rt.u32; getI32$Buf: () => rt.i32; getI32Le$Buf: () => rt.i32; getI32Ne$Buf: () => rt.i32; getU64$Buf: () => rt.u64; getU64Le$Buf: () => rt.u64; getU64Ne$Buf: () => rt.u64; getI64$Buf: () => rt.i64; getI64Le$Buf: () => rt.i64; getI64Ne$Buf: () => rt.i64; getU128$Buf: () => rt.u128; getU128Le$Buf: () => rt.u128; getU128Ne$Buf: () => rt.u128; getI128$Buf: () => rt.i128; getI128Le$Buf: () => rt.i128; getI128Ne$Buf: () => rt.i128; getUint$Buf: (a0: rt.usize) => rt.u64; getUintLe$Buf: (a0: rt.usize) => rt.u64; getUintNe$Buf: (a0: rt.usize) => rt.u64; getInt$Buf: (a0: rt.usize) => rt.i64; getIntLe$Buf: (a0: rt.usize) => rt.i64; getIntNe$Buf: (a0: rt.usize) => rt.i64; getF32$Buf: () => rt.f32; getF32Le$Buf: () => rt.f32; getF32Ne$Buf: () => rt.f32; getF64$Buf: () => rt.f64; getF64Le$Buf: () => rt.f64; getF64Ne$Buf: () => rt.f64; tryCopyToSlice$Buf: (a0: rt.ByteSlice) => rt.Result<undefined, TryGetError.TryGetError>; tryGetU8$Buf: () => rt.Result<rt.u8, TryGetError.TryGetError>; tryGetI8$Buf: () => rt.Result<rt.i8, TryGetError.TryGetError>; tryGetU16$Buf: () => rt.Result<rt.u16, TryGetError.TryGetError>; tryGetU16Le$Buf: () => rt.Result<rt.u16, TryGetError.TryGetError>; tryGetU16Ne$Buf: () => rt.Result<rt.u16, TryGetError.TryGetError>; tryGetI16$Buf: () => rt.Result<rt.i16, TryGetError.TryGetError>; tryGetI16Le$Buf: () => rt.Result<rt.i16, TryGetError.TryGetError>; tryGetI16Ne$Buf: () => rt.Result<rt.i16, TryGetError.TryGetError>; tryGetU32$Buf: () => rt.Result<rt.u32, TryGetError.TryGetError>; tryGetU32Le$Buf: () => rt.Result<rt.u32, TryGetError.TryGetError>; tryGetU32Ne$Buf: () => rt.Result<rt.u32, TryGetError.TryGetError>; tryGetI32$Buf: () => rt.Result<rt.i32, TryGetError.TryGetError>; tryGetI32Le$Buf: () => rt.Result<rt.i32, TryGetError.TryGetError>; tryGetI32Ne$Buf: () => rt.Result<rt.i32, TryGetError.TryGetError>; tryGetU64$Buf: () => rt.Result<rt.u64, TryGetError.TryGetError>; tryGetU64Le$Buf: () => rt.Result<rt.u64, TryGetError.TryGetError>; tryGetU64Ne$Buf: () => rt.Result<rt.u64, TryGetError.TryGetError>; tryGetI64$Buf: () => rt.Result<rt.i64, TryGetError.TryGetError>; tryGetI64Le$Buf: () => rt.Result<rt.i64, TryGetError.TryGetError>; tryGetI64Ne$Buf: () => rt.Result<rt.i64, TryGetError.TryGetError>; tryGetU128$Buf: () => rt.Result<rt.u128, TryGetError.TryGetError>; tryGetU128Le$Buf: () => rt.Result<rt.u128, TryGetError.TryGetError>; tryGetU128Ne$Buf: () => rt.Result<rt.u128, TryGetError.TryGetError>; tryGetI128$Buf: () => rt.Result<rt.i128, TryGetError.TryGetError>; tryGetI128Le$Buf: () => rt.Result<rt.i128, TryGetError.TryGetError>; tryGetI128Ne$Buf: () => rt.Result<rt.i128, TryGetError.TryGetError>; tryGetUint$Buf: (a0: rt.usize) => rt.Result<rt.u64, TryGetError.TryGetError>; tryGetUintLe$Buf: (a0: rt.usize) => rt.Result<rt.u64, TryGetError.TryGetError>; tryGetUintNe$Buf: (a0: rt.usize) => rt.Result<rt.u64, TryGetError.TryGetError>; tryGetInt$Buf: (a0: rt.usize) => rt.Result<rt.i64, TryGetError.TryGetError>; tryGetIntLe$Buf: (a0: rt.usize) => rt.Result<rt.i64, TryGetError.TryGetError>; tryGetIntNe$Buf: (a0: rt.usize) => rt.Result<rt.i64, TryGetError.TryGetError>; tryGetF32$Buf: () => rt.Result<rt.f32, TryGetError.TryGetError>; tryGetF32Le$Buf: () => rt.Result<rt.f32, TryGetError.TryGetError>; tryGetF32Ne$Buf: () => rt.Result<rt.f32, TryGetError.TryGetError>; tryGetF64$Buf: () => rt.Result<rt.f64, TryGetError.TryGetError>; tryGetF64Le$Buf: () => rt.Result<rt.f64, TryGetError.TryGetError>; tryGetF64Ne$Buf: () => rt.Result<rt.f64, TryGetError.TryGetError>; copyToBytes$Buf: (a0: rt.usize) => rt.ByteSlice };
+	| { pieces$Leased: () => rt.usize; skip$Leased: (a0: Buf.Buf) => void; remaining$Buf: () => rt.usize; chunk$Buf: () => rt.ByteSlice; advance$Buf: (a0: rt.usize) => void; hasRemaining$Buf: () => boolean; copyToSlice$Buf: (a0: rt.ByteSlice) => void; getU8$Buf: () => rt.u8; getI8$Buf: () => rt.i8; getU16$Buf: () => rt.u16; getU16Le$Buf: () => rt.u16; getU16Ne$Buf: () => rt.u16; getI16$Buf: () => rt.i16; getI16Le$Buf: () => rt.i16; getI16Ne$Buf: () => rt.i16; getU32$Buf: () => rt.u32; getU32Le$Buf: () => rt.u32; getU32Ne$Buf: () => rt.u32; getI32$Buf: () => rt.i32; getI32Le$Buf: () => rt.i32; getI32Ne$Buf: () => rt.i32; getU64$Buf: () => rt.u64; getU64Le$Buf: () => rt.u64; getU64Ne$Buf: () => rt.u64; getI64$Buf: () => rt.i64; getI64Le$Buf: () => rt.i64; getI64Ne$Buf: () => rt.i64; getU128$Buf: () => rt.u128; getU128Le$Buf: () => rt.u128; getU128Ne$Buf: () => rt.u128; getI128$Buf: () => rt.i128; getI128Le$Buf: () => rt.i128; getI128Ne$Buf: () => rt.i128; getUint$Buf: (a0: rt.usize) => rt.u64; getUintLe$Buf: (a0: rt.usize) => rt.u64; getUintNe$Buf: (a0: rt.usize) => rt.u64; getInt$Buf: (a0: rt.usize) => rt.i64; getIntLe$Buf: (a0: rt.usize) => rt.i64; getIntNe$Buf: (a0: rt.usize) => rt.i64; getF32$Buf: () => rt.f32; getF32Le$Buf: () => rt.f32; getF32Ne$Buf: () => rt.f32; getF64$Buf: () => rt.f64; getF64Le$Buf: () => rt.f64; getF64Ne$Buf: () => rt.f64; tryCopyToSlice$Buf: (a0: rt.ByteSlice) => rt.Result<undefined, TryGetError.TryGetError>; tryGetU8$Buf: () => rt.Result<rt.u8, TryGetError.TryGetError>; tryGetI8$Buf: () => rt.Result<rt.i8, TryGetError.TryGetError>; tryGetU16$Buf: () => rt.Result<rt.u16, TryGetError.TryGetError>; tryGetU16Le$Buf: () => rt.Result<rt.u16, TryGetError.TryGetError>; tryGetU16Ne$Buf: () => rt.Result<rt.u16, TryGetError.TryGetError>; tryGetI16$Buf: () => rt.Result<rt.i16, TryGetError.TryGetError>; tryGetI16Le$Buf: () => rt.Result<rt.i16, TryGetError.TryGetError>; tryGetI16Ne$Buf: () => rt.Result<rt.i16, TryGetError.TryGetError>; tryGetU32$Buf: () => rt.Result<rt.u32, TryGetError.TryGetError>; tryGetU32Le$Buf: () => rt.Result<rt.u32, TryGetError.TryGetError>; tryGetU32Ne$Buf: () => rt.Result<rt.u32, TryGetError.TryGetError>; tryGetI32$Buf: () => rt.Result<rt.i32, TryGetError.TryGetError>; tryGetI32Le$Buf: () => rt.Result<rt.i32, TryGetError.TryGetError>; tryGetI32Ne$Buf: () => rt.Result<rt.i32, TryGetError.TryGetError>; tryGetU64$Buf: () => rt.Result<rt.u64, TryGetError.TryGetError>; tryGetU64Le$Buf: () => rt.Result<rt.u64, TryGetError.TryGetError>; tryGetU64Ne$Buf: () => rt.Result<rt.u64, TryGetError.TryGetError>; tryGetI64$Buf: () => rt.Result<rt.i64, TryGetError.TryGetError>; tryGetI64Le$Buf: () => rt.Result<rt.i64, TryGetError.TryGetError>; tryGetI64Ne$Buf: () => rt.Result<rt.i64, TryGetError.TryGetError>; tryGetU128$Buf: () => rt.Result<rt.u128, TryGetError.TryGetError>; tryGetU128Le$Buf: () => rt.Result<rt.u128, TryGetError.TryGetError>; tryGetU128Ne$Buf: () => rt.Result<rt.u128, TryGetError.TryGetError>; tryGetI128$Buf: () => rt.Result<rt.i128, TryGetError.TryGetError>; tryGetI128Le$Buf: () => rt.Result<rt.i128, TryGetError.TryGetError>; tryGetI128Ne$Buf: () => rt.Result<rt.i128, TryGetError.TryGetError>; tryGetUint$Buf: (a0: rt.usize) => rt.Result<rt.u64, TryGetError.TryGetError>; tryGetUintLe$Buf: (a0: rt.usize) => rt.Result<rt.u64, TryGetError.TryGetError>; tryGetUintNe$Buf: (a0: rt.usize) => rt.Result<rt.u64, TryGetError.TryGetError>; tryGetInt$Buf: (a0: rt.usize) => rt.Result<rt.i64, TryGetError.TryGetError>; tryGetIntLe$Buf: (a0: rt.usize) => rt.Result<rt.i64, TryGetError.TryGetError>; tryGetIntNe$Buf: (a0: rt.usize) => rt.Result<rt.i64, TryGetError.TryGetError>; tryGetF32$Buf: () => rt.Result<rt.f32, TryGetError.TryGetError>; tryGetF32Le$Buf: () => rt.Result<rt.f32, TryGetError.TryGetError>; tryGetF32Ne$Buf: () => rt.Result<rt.f32, TryGetError.TryGetError>; tryGetF64$Buf: () => rt.Result<rt.f64, TryGetError.TryGetError>; tryGetF64Le$Buf: () => rt.Result<rt.f64, TryGetError.TryGetError>; tryGetF64Ne$Buf: () => rt.Result<rt.f64, TryGetError.TryGetError>; copyToBytes$Buf: (a0: rt.usize) => rt.ByteSlice };
 
 //# sourceMappingURL=buf.Leased.ts.map

ts/fixtures/stock/expected/buf.Pieces.ts

@@ -4,7 +4,8 @@ import * as rt from "./rt.ts";
 import { out$f32, out$f64, out$i64, out$i8, out$u128, out$u16, out$u64, out$u8 } from "./lib.ts";
 import type * as Provided from "./buf.Provided.ts";
 import { panicAdvance, panicDoesNotFit } from "./bytes.ts";
-import { signExtend } from "./bytes/buf/buf_impl.ts";
+import { signExtend, hasRemaining$bytes_Buf_mut_dyn_bytes_Buf, remaining$bytes_Buf_mut_dyn_bytes_Buf } from "./bytes/buf/buf_impl.ts";
+import type * as Buf from "./bytes/buf/buf_impl.Buf.ts";
 import * as Chain from "./bytes/buf/chain.Chain.ts";
 import { new_$mut_buf_Pieces as take_new_$mut_buf_Pieces } from "./bytes/buf/take.ts";
 import type * as Take from "./bytes/buf/take.Take.ts";
@@ -189,6 +190,15 @@ export function pieces$buf_Leased(self: Pieces): rt.usize {
 	return self.parts.length;
 }
 
+/** Reads a byte of `other`, then skips as many bytes as it has left. */
+export function skip$buf_Leased(self: Pieces, other: Buf.Buf): void {
+	if (hasRemaining$bytes_Buf_mut_dyn_bytes_Buf(other)) {
+		other.advance$Buf(1);
+	}
+	const _7: rt.usize = rt.min(remaining$bytes_Buf_mut_dyn_bytes_Buf(other), remaining$bytes_Buf_mut(self));
+	advance$bytes_Buf(self, _7);
+}
+
 /**
  * Returns true if there are any more bytes to consume
  *

ts/fixtures/stock/expected/buf.ts

@@ -2286,7 +2286,8 @@ export function readAll$ref_slice_u8(buf: rt.Place<rt.ByteSlice>, ops: rt.ByteSl
 /**
  * The reads of `reads` through a `dyn Buf` of each buffer: called on the object, through
  * the impls forwarding through a `&mut` to one and a `Box` of one, and through the crate's
- * own trait over `Buf`. A box drops what it owns once.
+ * own trait over `Buf`, whose method takes another `dyn Buf`. A box drops what it owns
+ * once.
  */
 export function dyns(dataData: Uint8Array, dataStart: number, dataLen: number, out: rt.ByteVec): void {
 	let _30!: Buf.Buf;
@@ -2345,6 +2346,9 @@ export function dyns(dataData: Uint8Array, dataStart: number, dataLen: number, o
 		rt.byteVecPush(out, drops.value.v);
 		const leased: Leased.Leased = new of$buf_Pieces(Pieces.new(input.data, input.start, input.length, cut));
 		rt.byteVecPush(out, leased.pieces$Leased() & 0xff);
+		let skipped: rt.ByteSlice = ops2;
+		leased.skip$Leased(new ofPlace$ref_slice_u8(rt.place(() => skipped, (value5) => skipped = value5)));
+		rt.byteVecPush(out, skipped.length & 0xff);
 		rt.byteVecExtendFromSlice(out, rt.byteVecSlice(readAll$dyn_buf_Leased(leased, ops2, out)));
 		rt.byteVecPush(out, leased.pieces$Leased() & 0xff);
 		rt.drop(leased);

ts/fixtures/stock/expected/lib.ts

@@ -486,6 +486,10 @@ export class of$buf_Pieces {
 		return Pieces.remaining$bytes_Buf(this.v);
 	}
 
+	skip$Leased(a: Buf.Buf): void {
+		return Pieces.skip$buf_Leased(this.v, a);
+	}
+
 	tryCopyToSlice$Buf(a: rt.ByteSlice): rt.Result<undefined, TryGetError.TryGetError> {
 		return Pieces.tryCopyToSlice$bytes_Buf(this.v, a);
 	}

ts/fixtures/stock/src/buf.rs

@@ -276,12 +276,21 @@ fn read_all<B: Buf + ?Sized>(buf: &mut B, ops: &[u8], out: &mut Vec<u8>) -> Vec<
 /// A buffer of the crate's own over `Buf`, as moq's transports lend a stream's chunks.
 trait Leased: Buf {
 	fn pieces(&self) -> usize;
+	/// Reads a byte of `other`, then skips as many bytes as it has left.
+	fn skip(&mut self, other: &mut dyn Buf);
 }
 
 impl Leased for Pieces {
 	fn pieces(&self) -> usize {
 		self.parts.len()
 	}
+
+	fn skip(&mut self, other: &mut dyn Buf) {
+		if other.has_remaining() {
+			other.advance(1);
+		}
+		self.advance(other.remaining().min(self.remaining()));
+	}
 }
 
 /// Pieces that count their drops.
@@ -309,7 +318,8 @@ impl Drop for Counted {
 
 /// The reads of `reads` through a `dyn Buf` of each buffer: called on the object, through
 /// the impls forwarding through a `&mut` to one and a `Box` of one, and through the crate's
-/// own trait over `Buf`. A box drops what it owns once.
+/// own trait over `Buf`, whose method takes another `dyn Buf`. A box drops what it owns
+/// once.
 pub fn dyns(data: &[u8], out: &mut Vec<u8>) {
 	let [kind, cut, ops @ ..] = data else {
 		return;
@@ -351,6 +361,9 @@ pub fn dyns(data: &[u8], out: &mut Vec<u8>) {
 
 	let mut leased: Box<dyn Leased> = Box::new(Pieces::new(input, cut));
 	out.push(leased.pieces() as u8);
+	let mut skipped = ops;
+	leased.skip(&mut skipped);
+	out.push(skipped.len() as u8);
 	let rest = read_all(&mut *leased, ops, out);
 	out.extend_from_slice(&rest);
 	out.push(leased.pieces() as u8);

ts/src/lower/copy.rs

@@ -1156,12 +1156,9 @@ impl<'tcx> Visitor<'tcx> for BodyWrites<'_, '_, '_, 'tcx> {
 			&& let ty::FnDef(def_id, args) = *constant.ty().kind()
 			&& !self.crate_fn(def_id, args.skip_binder())
 		{
-			let sig = self
-				.tcx
-				.fn_sig(def_id)
-				.instantiate(self.tcx, args.skip_binder())
-				.skip_norm_wip();
-			if let Some(&this) = sig.skip_binder().inputs().first()
+			let sig = self.tcx.fn_sig(def_id).instantiate(self.tcx, args.skip_binder());
+			let sig = self.tcx.instantiate_bound_regions_with_erased(sig.skip_norm_wip());
+			if let Some(&this) = sig.inputs().first()
 				&& let Some(value) = replaces(self.tcx, def_id, this)
 			{
 				self.replace(value);
@@ -1181,7 +1178,7 @@ impl<'tcx> Visitor<'tcx> for BodyWrites<'_, '_, '_, 'tcx> {
 				}
 				_ => None,
 			};
-			for (i, &input) in sig.skip_binder().inputs().iter().enumerate() {
+			for (i, &input) in sig.inputs().iter().enumerate() {
 				let fresh = replace
 					&& call.is_some_and(|(args, made)| {
 						args.get(i)