feat(dom): prove INT-08 reconciler runs end-to-end; ship the e2e harness

affinescript-dom/e2e/dom_host.mjs

@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: MPL-2.0
+// e2e host for dom_drive.wasm — Int-handle DOM, mutation log, assertions.
+import assert from 'node:assert/strict';
+import { readFile } from 'node:fs/promises';
+
+let inst = null;
+const readString = (ptr) => {
+  const dv = new DataView(inst.exports.memory.buffer);
+  const len = dv.getUint32(ptr, true);
+  return new TextDecoder('utf-8').decode(
+    new Uint8Array(inst.exports.memory.buffer, ptr + 4, len));
+};
+
+// handle 1 = #root
+const nodes = new Map([[1, { tag: '#root', attrs: new Map(), children: [], text: null }]]);
+let next = 2;
+const log = [];
+const mk = (n) => { const h = next++; nodes.set(h, n); return h; };
+
+const env = {
+  dom_query_selector: (p) => { const s = readString(p); log.push(`query(${s})`); return s === '#root' ? 1 : 0; },
+  dom_create_element: (p) => { const t = readString(p); const h = mk({ tag: t, attrs: new Map(), children: [], text: null }); log.push(`createElement(${t})=#${h}`); return h; },
+  dom_create_text_node: (p) => { const s = readString(p); const h = mk({ tag: '#text', attrs: new Map(), children: [], text: s }); log.push(`createText("${s}")=#${h}`); return h; },
+  dom_append_child: (p, c) => { nodes.get(p).children.push(c); log.push(`append(#${p},#${c})`); },
+  dom_replace_child: (p, o, n) => { const cs = nodes.get(p).children; const i = cs.indexOf(o); assert.ok(i >= 0, `replace: #${o} not under #${p}`); cs[i] = n; log.push(`replace(#${p},#${o}->#${n})`); },
+  dom_remove_child: (p, c) => { const cs = nodes.get(p).children; const i = cs.indexOf(c); assert.ok(i >= 0, `remove: #${c} not under #${p}`); cs.splice(i, 1); log.push(`remove(#${p},#${c})`); },
+  dom_child_at: (p, i) => { const c = nodes.get(p).children[i] ?? 0; log.push(`childAt(#${p},${i})=#${c}`); return c; },
+  dom_set_attribute: (el, n, v) => { const name = readString(n), val = readString(v); nodes.get(el).attrs.set(name, val); log.push(`setAttr(#${el},${name}=${val})`); },
+  dom_remove_attribute: (el, n) => { const name = readString(n); nodes.get(el).attrs.delete(name); log.push(`removeAttr(#${el},${name})`); },
+  dom_set_text: (el, p) => { const s = readString(p); nodes.get(el).text = s; log.push(`setText(#${el},"${s}")`); },
+  dom_str_eq: (a, b) => (readString(a) === readString(b) ? 1 : 0),
+};
+
+const dump = (h, d = 0) => {
+  const n = nodes.get(h);
+  const attrs = [...n.attrs].map(([k, v]) => ` ${k}="${v}"`).join('');
+  const line = n.tag === '#text' ? `"${n.text}"` : `<${n.tag}${attrs}> #${h}`;
+  return ['  '.repeat(d) + line, ...n.children.flatMap((c) => dump(c, d + 1))].join('\n');
+};
+
+const bytes = await readFile(process.argv[2]);
+const { instance } = await WebAssembly.instantiate(bytes, {
+  env, wasi_snapshot_preview1: { fd_write: () => 0 },
+});
+inst = instance;
+
+const ret = inst.exports.main();
+console.log('main() =', ret);
+console.log('--- mutation log ---'); console.log(log.join('\n'));
+console.log('--- final DOM under #root ---'); console.log(dump(1));
+
+// assertions: reconcile patched in place
+const root = nodes.get(1);
+assert.equal(root.children.length, 1, 'root has exactly one child');
+const div = nodes.get(root.children[0]);
+assert.equal(div.tag, 'div');
+assert.equal(div.attrs.get('id'), 'app');
+assert.equal(div.attrs.get('title'), 't2', 'title added by patch_attrs');
+assert.ok(!div.attrs.has('class'), 'class removed by patch_attrs');
+assert.equal(div.children.length, 1, 'span child removed by while-loop reconcile');
+const t = nodes.get(div.children[0]);
+assert.equal(t.tag, '#text');
+assert.equal(t.text, 'world', 'text updated in place');
+assert.equal(ret, root.children[0], 'reconcile returned the in-place div handle');
+console.log('ALL ASSERTIONS PASS — reconciler ran end-to-end (loops executed)');

affinescript-dom/e2e/driver_main.affine

@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: MPL-2.0
+// e2e driver `main` for the DOM reconciler. NOT standalone: `run.sh`
+// concatenates `../src/dom.affine` + this file (codegen is single-pass in
+// declaration order, so `main` must come after the functions it calls).
+//
+// Exercises every loop-bearing path (the #255 class): render's attr +
+// children loops, patch_attrs' add + remove loops (via attr_has), and the
+// `while` child-reconcile loop (in-place text patch at i=0, surplus-child
+// removal at i=1).
+//
+// Affine detail: `mount` consumes its tree, so the reconcile call gets a
+// freshly built copy — reusing `old_tree` would be a use-after-move type
+// error. The discipline the module sells is load-bearing in its own test.
+fn main() -> Int {
+  let old_tree = h("div", [("id", "app"), ("class", "old")],
+                   [text("hello"), h("span", [], [text("x")])]);
+  let ok = mount("#root", old_tree);
+  if ok {
+    let parent = dom_query_selector("#root");
+    let old_node = dom_child_at(parent, 0);
+    let old_v = h("div", [("id", "app"), ("class", "old")],
+                  [text("hello"), h("span", [], [text("x")])]);
+    let new_v = h("div", [("id", "app"), ("title", "t2")],
+                  [text("world")]);
+    reconcile(parent, old_node, old_v, new_v)
+  } else {
+    0 - 1
+  }
+}

affinescript-dom/e2e/run.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: MPL-2.0
+# End-to-end runtime test for the DOM reconciler (INT-08 / #183).
+# Concatenates src/dom.affine + driver_main.affine, compiles to core-WASM,
+# runs it under Node against an Int-handle host DOM (dom_host.mjs), and
+# asserts the mutation log + final tree. Exit 0 = the reconciler (including
+# every for/while loop — the #255 class) executed correctly in compiled wasm.
+#
+# Requires: the compiler built (dune build → _build/default/bin/main.exe;
+# override with AFFINESCRIPT_BIN=/path/to/main.exe)
+# and Node ≥ 18 on PATH. Skips (exit 0, loud) if either is missing so the
+# harness can sit in CI paths that lack the OCaml toolchain.
+set -uo pipefail
+cd "$(dirname "$0")"
+REPO="$(cd ../.. && pwd)"
+BIN="${AFFINESCRIPT_BIN:-$REPO/_build/default/bin/main.exe}"
+[ -x "$BIN" ] || { echo "SKIP: compiler not built ($BIN missing) — run dune build"; exit 0; }
+command -v node >/dev/null 2>&1 || { echo "SKIP: node not on PATH"; exit 0; }
+
+TMP="$(mktemp -d)"
+trap 'rm -rf "$TMP"' EXIT
+cat ../src/dom.affine driver_main.affine > "$TMP/dom_drive.affine"
+"$BIN" compile "$TMP/dom_drive.affine" -o "$TMP/dom_drive.wasm"
+node dom_host.mjs "$TMP/dom_drive.wasm"

affinescript-dom/src/dom.affine

@@ -15,12 +15,13 @@
  *
  * GATE: this module compiles end-to-end (resolve → typecheck → codegen
  * → wasm), the same bar as the Stage-C stdlib AOT suite. RUNTIME is
- * blocked by #255 — a pre-existing wasm-codegen defect where `for-in` /
- * `while` loop bodies never execute in the compiled module (so
- * `vnode_len`, the attr loops, and the child reconcile loop iterate
- * zero times). The reconciler logic here is correct AffineScript; it
- * will run once #255 lands. No runtime e2e harness is shipped until
- * then (a harness that cannot pass would be dishonest).
+ * verified end-to-end (2026-07-07): #255 — the wasm loop-codegen defect
+ * that blocked it — was fixed in PR #257 (closed 2026-05-19), and
+ * `../e2e/run.sh` now drives this reconciler against a real Int-handle
+ * host DOM: mount, in-place attr patch (add + remove), in-place text
+ * update, and surplus-child removal, with the mutation log asserted.
+ * `vnode_len`, the attr loops, and the `while` child-reconcile loop all
+ * execute in the compiled wasm.
  *
  * Codegen note: AffineScript codegen is single-pass in source
  * declaration order (lib/codegen.ml `func_indices`), so a function may

docs/ECOSYSTEM.adoc

@@ -149,9 +149,10 @@ The contract is *narrower than older prose claimed* and is exactly this:
 (non-parsing 39-line stub) renamed to canonical `src/dom.affine` and
 replaced with a real VDOM + render + mount + minimal-mutation
 reconciler that compiles end-to-end. The #255 wasm loop-codegen defect that
-gated its runtime is *FIXED* (PR #257; issue closed 2026-05-19), so the
-runtime is no longer blocked by it; end-to-end DOM runtime remains to be
-re-verified.
+gated its runtime is *FIXED* (PR #257; issue closed 2026-05-19), and the
+runtime is *VERIFIED end-to-end* (2026-07-07): `affinescript-dom/e2e/run.sh`
+drives mount + in-place attr patch + text update + surplus-child removal
+against a real Int-handle host DOM, mutation log asserted.
 
 |`affinescript-pixijs` |skeleton |Migration-prerequisite scaffold (#56).
 
@@ -170,8 +171,9 @@ canonical `affinescript tea-bridge` + a re-entrancy fixture.
 shipped + closed 2026-05-31 as `packages/affine-js/loader.js` — already
 host-agnostic (Deno/Node/browser parity). Whether the satellite repo
 still earns its keep (vs. folding into `affine-js`) is the open question
-in #489; revisit when INT-08 reconciler runtime (#183) is re-verified (#255
-loop-codegen fixed via #257) and dictates any DOM-specific loader surface.
+in #489; INT-08 reconciler runtime (#183) is verified end-to-end 2026-07-07
+(`affinescript-dom/e2e/run.sh`; #255 fixed via #257) — revisit when it
+dictates any DOM-specific loader surface.
 
 |`affinescript-cadre` |scaffold |Was imaginary until #175. Router/navigation
 satellite (internal `lib/tea_router.ml` contract exists).
@@ -271,17 +273,18 @@ cleared (#253). Router/nav = separate INT-09
 |INT-08 |DOM reconciler in `affinescript-dom` |#183 |reconciler
 implemented + compiles (resolve→typecheck→codegen→wasm); `.as`→`.affine`
 corrected. INT-02 dep cleared. #255 (wasm loop-codegen defect) that gated
-the runtime is FIXED (PR #257, closed 2026-05-19); runtime to be re-verified
-end-to-end
+the runtime is FIXED (PR #257, closed 2026-05-19); runtime VERIFIED
+end-to-end 2026-07-07 via `affinescript-dom/e2e/run.sh` (mount + attr
+patch + text update + child removal, mutation log asserted)
 |INT-09 |`affinescript-cadre` router/navigation runtime |ledger-only
 |planned (blocked by INT-07)
 |INT-10 |LSP distribution (`affinescript-lsp`) |#282 |unblocked —
 distribution decided (ADR-019: Releases + thin Deno/JSR shim, #260).
 Consumes the shim once #260 S2/S3 land
 |INT-11 |Browser host parity (DOM loader + reconciler end-to-end) |
-ledger-only |planned (INT-02 dep cleared 2026-05-31 via #179; #255 that
-gated INT-08 runtime is fixed via #257 — pending INT-08 runtime
-re-verification). Satellite-repo question = #489.
+ledger-only |planned (INT-02 dep cleared 2026-05-31 via #179; INT-08
+runtime verified end-to-end 2026-07-07 under Node — browser-host parity
+is the remaining leg). Satellite-repo question = #489.
 |INT-12 |typed-wasm convergence: AffineScript-emitted fixtures into the
 typed-wasm cross-compat suite (closes the Stage-E runway) |ledger-only |
 planned (Stage E; coordinates with `hyperpolymath/typed-wasm` C5.1)

docs/TECH-DEBT.adoc

@@ -424,7 +424,8 @@ licence in root `LICENSE`).
 (TeaApp/parseTeaLayout, Linear-msg enforced); INT-01 cleared (#253)
 |INT-08 |DOM reconciler |S2 |#183 implemented + compiles; `.as`→`.affine`
 fixed; #255 (wasm loop-codegen defect) that gated the runtime is fixed
-(PR #257, closed 2026-05-19) — runtime to be re-verified end-to-end
+(PR #257, closed 2026-05-19) — runtime VERIFIED end-to-end 2026-07-07 via
+`affinescript-dom/e2e/run.sh`
 |INT-10 |`affinescript-lsp` distribution |S2 |**DONE end-to-end live**
 (#282, ADR-019 S4): LSP resolves the compiler via `AFFINESCRIPT_COMPILER`
 → `affinescript` on `PATH` → the `@hyperpolymath/affinescript` shim

docs/bindings-roadmap.adoc

@@ -84,10 +84,10 @@ no further significant ReScript → AffineScript work is tractable.
 |idaptik `src/app/multiplayer/PhoenixSocket.res` + LobbyManager; needed for any multiplayer / sync-server feature.
 
 |7
-|*DOM* — re-verify the reconciler runs end-to-end (the `for-in` / `while` codegen gap, issue #255, is fixed)
-|`●` / `◯` #255-fixed; re-verify runtime
+|*DOM* — reconciler runs end-to-end (verified 2026-07-07, `affinescript-dom/e2e/run.sh`; the `for-in` / `while` codegen gap, issue #255, is fixed)
+|`●` verified
 |`affinescript-dom`
-|187-line virtual-DOM + reconciler exists and compiles. The wasm loop-codegen defect (#255) that blocked its runtime is *fixed* (PR #257, issue closed 2026-05-19); end-to-end runtime remains to be re-verified. *Was not a binding gap — a codegen bug, now resolved.*
+|187-line virtual-DOM + reconciler exists, compiles, and *runs*: verified end-to-end 2026-07-07 (`affinescript-dom/e2e/run.sh` — mount, attr patch, text update, surplus-child removal against an Int-handle host DOM, mutation log asserted). The wasm loop-codegen defect (#255) that blocked it was fixed in PR #257. *Was not a binding gap — a codegen bug, now resolved and runtime-proven.*
 
 |8
 |*WebGL / Canvas2D context* (HTMLCanvasElement, getContext, drawImage, fillRect, transform stack)