quest: plan the model refusals the moq pin bump added

quest/m2/ts-model/README.md

@@ -55,11 +55,22 @@ refuses for good, and smallvec's union over a type parameter and raw parts (10)
 [unsafe](/quest/m3/ts-unsafe.md), so both need safe `cfg(rust2_ts)` twins or bindings
 there, as does the `unsafe` slice of `model/frame.rs`'s `Filled`.
 
+Decided with the maintainer on 2026-11-04, from a census at the bumped pin
+(moq-dev/rust2#390): the refusals no quest owned became the children below. ✅ arrayvec's
+`ArrayString` needs three of them (const generic types, `begin_panic`, `str::as_ptr`),
+kept separate since each lands alone; rejected: one quest for `ArrayString`.
+
 ## Required
 
 - [Iterators into a crate's own collections](/quest/m2/ts-model/from-iterator.md) - `collect`, `flat_map`, and `flatten` through moq-pattern's `Patterns`
 - [Bytes from an owner that drops](/quest/m2/ts-model/bytes-owner.md) - `Bytes::from_owner` of a frame's segment
 - [rangemap](/quest/m2/ts-model/rangemap.md) - B-tree ranges by a borrowed key, and std's iterators in a crate's fields
 - [Addresses as identity](/quest/m2/ts-model/addresses.md) - `Arc::as_ptr(a) as usize` as a key, which needs a decision
+- [Option fields at a unit instance](/quest/m2/ts-model/unit-option-fields.md) - `Idle<()>`'s `Option<T>` field tells `Some(())` from `None`
+- [Const generic types](/quest/m2/ts-model/const-generics.md) - `ArrayString<CAP>` and other types with const parameters
+- [panic! in a 2015 or 2018 crate](/quest/m2/ts-model/begin-panic.md) - the `begin_panic` mapping keyed by its defining module
+- [A string's bytes through its pointer](/quest/m2/ts-model/str-as-ptr.md) - `str::as_ptr` reads the string's UTF-8
+- [Scheduler hints](/quest/m2/ts-model/scheduler-hints.md) - `thread::yield_now` and `hint::spin_loop` translate to nothing
+- [Slices not yet written](/quest/m2/ts-model/uninit-slices.md) - `Box::new_uninit_slice` of a frame's segment
 
 Public API: the translator's output for moq-net's model.

quest/m2/ts-model/begin-panic.md

@@ -0,0 +1,15 @@
+# [XS] panic! in a 2015 or 2018 crate
+
+## Goal
+
+[rust2-ts](/ts/README.md) translates `panic!("literal")` in a 2015 or 2018 edition crate,
+which expands to `std::rt::begin_panic`, as it does in 2021, proven by a 2018-edition
+panics fixture against native Rust. Today arrayvec's is refused.
+
+## Plan
+
+The mapping is keyed by `("rt", "begin_panic")`, but `library::key` builds keys from the
+defining module, and std defines `begin_panic` in `std::panicking` and only re-exports it
+from `rt`, so the mapping never matches. No fixture used a pre-2021 `panic!`.
+
+Public API: the translator's output.

quest/m2/ts-model/const-generics.md

@@ -0,0 +1,15 @@
+# [M] Const generic types
+
+## Goal
+
+[rust2-ts](/ts/README.md) translates structs and enums with const parameters, such as
+arrayvec's `ArrayString<CAP>` and `ArrayVec<T, N>`, so each instance's body reads its own
+`N`, proven by differential tests against native Rust. At the moq pin it refuses once in
+the model (`Path::join`'s `ArrayString`) and 8 times in moq-net whole.
+
+## Plan
+
+Functions with const parameters already translate per instance; types do not yet. Check
+how the choice interacts with a type's class being shared across instances.
+
+Public API: the translator's output.

quest/m2/ts-model/scheduler-hints.md

@@ -0,0 +1,14 @@
+# [XS] Scheduler hints
+
+## Goal
+
+[rust2-ts](/ts/README.md) translates `thread::yield_now` and `hint::spin_loop` to nothing,
+as neither promises anything observable, proven by a differential test against native
+Rust. At the moq pin `model/frame.rs`'s `attach` refuses on `yield_now`.
+
+## Plan
+
+A spin loop that waits on another thread hangs natively on one thread too, so translating
+the hint to nothing matches Rust.
+
+Public API: the translator's output.

quest/m2/ts-model/str-as-ptr.md

@@ -0,0 +1,15 @@
+# [S] A string's bytes through its pointer
+
+## Goal
+
+[rust2-ts](/ts/README.md) translates `str::as_ptr` as a read-only pointer to the string's
+UTF-8, so `ptr::copy_nonoverlapping` and `slice::from_raw_parts` read what Rust reads,
+proven by differential tests against native Rust. At the moq pin arrayvec's
+`ArrayString` refuses it once in the model and 3 times in moq-net whole.
+
+## Plan
+
+A `&str` stays a JS string (decided on #574), so the bytes are an encoding of it; a pointer into
+them must not let a write through it go unnoticed, which Rust forbids anyway for a `&str`.
+
+Public API: the translator's output.

quest/m3/ts-uninit-slices.md → quest/m2/ts-model/uninit-slices.md

@@ -11,5 +11,5 @@ differential tests against native Rust.
 A `MaybeUninit<T>` is a `T` in JS, and one of a byte is the byte, so a `[MaybeUninit<u8>]`
 is an `rs.ByteSlice`; `write_copy_of_slice` and a slice's `assume_init_ref` and
 `assume_init_mut` already map. `write_clone_of_slice` clones in without dropping what was
-there, unlike `clone_from_slice`. Found translating `spare_capacity_mut`; no consumer calls
-either yet.
+there, unlike `clone_from_slice`. Found translating `spare_capacity_mut`. moq-net's `model/frame.rs` calls
+`Box::<[u8]>::new_uninit_slice` in `Segment::new` at the moq pin.

quest/m2/ts-model/unit-option-fields.md

@@ -0,0 +1,18 @@
+# [S] Option fields of a generic type at a unit instance
+
+## Goal
+
+[rust2-ts](/ts/README.md) translates a generic type's `Option<T>` or `Poll<T>` field at an
+instance whose `T` is itself `undefined` or pending in JS, such as moq-net's `Idle<()>`
+(`util/idle.rs`'s `parked`) and tokio's `oneshot::Inner<()>`, proven by differential
+tests against native Rust. At the moq pin it refuses 16 times in the model and 24 in
+moq-net whole.
+
+## Plan
+
+The type's definition types the field `T | undefined`, which loses `Some(())` against
+`None` at `T = ()`; the field needs `rs.None` (or `rs.OuterPending`) where an instance
+can already be the bare value. Decide it per field from the instances the crate uses, not
+per type, and keep the bare form for every other instance.
+
+Public API: the translator's output.

quest/m3/README.md

@@ -22,8 +22,8 @@ generic std gap is planned here even when moq never calls it.
 - [rs.Slice](/quest/m3/ts-slice-object.md) - references to arrays of other values are a runtime slice too, and pointers compare by where they point
 - [Writes through iter_mut without a Place per item](/quest/m3/ts-iter-mut-places.md) - a loop over `iter_mut()` of copy values writes the slice's array by index
 - [rs.String](/quest/m3/ts-string-capacity.md) - `String`, `Box<str>`, and `&str` are a runtime type holding std's capacity
-- [Slices not yet written](/quest/m3/ts-uninit-slices.md) - `Box::new_uninit_slice` and `write_clone_of_slice` translate
 - [Throw only where Rust panics](/quest/m3/ts-runtime-throws.md) - no runtime `rust2-ts:` error where native Rust goes on: an exact slower path, or a refusal at translation
 - [rust2-ts with no ts.toml](/quest/m3/ts-configless.md) - a crate's whole `pub` API translates with no config and no bound items
 - [Buf on a deque of bytes](/quest/m3/ts-vecdeque-buf.md) - `bytes`' `Buf` for a deque of bytes translates
+- [std's panic messages hold std's capacity](/quest/m3/ts-panic-payload-capacity.md) - a hook reads native's `String` capacity from std's own formatted panics
 - [A B-tree drops as std's does](/quest/m3/ts-btree-drop-order.md) - keys and values drop node by node, in std's order

quest/m3/ts-panic-payload-capacity.md

@@ -0,0 +1,20 @@
+# [M] std's panic messages hold std's capacity
+
+## Goal
+
+A panic hook in code [rust2-ts](/ts/README.md) generates reads the same `String` capacity
+from std's own formatted panic messages (such as `slice index starts at {} but ends at
+{}`) as native Rust, proven by the panics fixture's hook against native Rust.
+
+## Plan
+
+Found in #574, which gives `String` its capacity: the runtime passes std's formatted messages as one string, so their
+capacity differs from std's, which builds them piece by piece (37 against 44 for that
+message). About 64 runtime sites pass such a message. Build each as std's `format!` does,
+without slowing the paths that never panic.
+
+Public API: the runtime's panic sites, not their messages.
+
+## Required
+
+- [rs.String](/quest/m3/ts-string-capacity.md) - `String` holds std's capacity, which a hook then reads