; Iter 18g.tidy.fu2 RED-test fixture 3/3: dynamic-tag partial-drop
; carve-out at let-close for an App-bound binder
; (drop.rs:580 fallback in `emit_inlined_partial_drop`).
;
; Shape:
;   - Same `Pair`/`Cell`/`Wrap` types as fixtures 1 and 2.
;   - `main` let-binds `p = (app build_pair)` — value is
;     `Term::App` (Own-returning), `is_rc_heap_allocated` returns
;     true → trackable.
;   - Body matches `p` as `MkPair a _` — slot 0 bound, slot 1 wild.
;     `moved_slots[p] = {0}`.
;   - `a` is consumed by `use_cell` (Own param) → `consume_count[a]
;     == 1`, arm-close drop skipped. `use_cell`'s body fully
;     destructures `a` and returns Int.
;   - At p's let-close: `consume_count[p] == 0`, `moves[p] = {0}`
;     non-empty, `value` is `Term::App` (not `Term::Ctor`) →
;     `emit_inlined_partial_drop` falls into the non-Ctor branch
;     (drop.rs:580) → shallow `ailang_rc_dec(p)`. p's outer cell
;     is freed; slot 1 (the second MkCell + its two MkWraps =
;     3 cells) leaks.
;
; Pre-fix:  live = 3 (one MkCell + two MkWrap children in slot 1).
; Post-fix: live = 0.

(module rc_app_let_partial_drop_leak

  (data Wrap
    (ctor MkWrap (con Int)))

  (data Cell
    (ctor MkCell (con Wrap) (con Wrap)))

  (data Pair
    (ctor MkPair (con Cell) (con Cell)))

  (fn build_pair
    (type
      (fn-type
        (params (con Int))
        (ret (own (con Pair)))))
    (params n)
    (body
      (term-ctor Pair MkPair
        (term-ctor Cell MkCell
          (term-ctor Wrap MkWrap n)
          (term-ctor Wrap MkWrap 2))
        (term-ctor Cell MkCell
          (term-ctor Wrap MkWrap 3)
          (term-ctor Wrap MkWrap 4)))))

  (fn use_cell
    (type
      (fn-type
        (params (own (con Cell)))
        (ret (con Int))))
    (params c)
    (body
      (match c
        (case (pat-ctor MkCell w1 w2) 1))))

  (fn main
    (type (fn-type (params) (ret (con Unit)) (effects IO)))
    (params)
    (body
      (let p (app build_pair 1)
        (do io/print_int
          (match p
            (case (pat-ctor MkPair a _)
              (app use_cell a))))))))