fix(zap): receipt validation works with nostr-tools 2.x SimplePool

After a successful split zap, validation errored: "Unable to initialize a relay
pool for receipt validation." The validator built a fresh `new SimplePool()` and
required `pool.list()`, but nostr-tools 2.x removed SimplePool.list() (the rest of
the app only has it because js/nostr/toolkit.js shims it). So validation always
failed even though the payment went through.

Fix: resolveReceiptListPool() applies the app's legacy .list shim
(shimLegacySimplePoolMethods) to the freshly created pool, and the gate now
accepts a listEvents override instead of hard-requiring pool.list.

tests/zap-receipt-pool.test.mjs: 2.x pool gets .list shimmed; createPool override
shimmed; listEvents override leaves the pool as-is; null when neither available.
Mutation-verified (removing the shim fails it).

Co-Authored-By: Claude Opus 4.8 <[email protected]>

js/payments/zapReceiptValidator.js

@@ -1,7 +1,11 @@
 // js/payments/zapReceiptValidator.js
 
 import { nostrToolsReady } from "../nostrToolsBootstrap.js";
-import { normalizeToolkitCandidate, readToolkitFromScope } from "../nostr/toolkit.js";
+import {
+  normalizeToolkitCandidate,
+  readToolkitFromScope,
+  shimLegacySimplePoolMethods,
+} from "../nostr/toolkit.js";
 import { userLogger } from "../utils/logger.js";
 import { bech32, bytesToHex, sha256 } from "../../vendor/crypto-helpers.bundle.min.js";
 
@@ -212,6 +216,37 @@ function buildValidationResult({
   };
 }
 
+// Build the relay pool used to fetch the zap receipt. nostr-tools 2.x SimplePool
+// no longer exposes .list(), so a freshly constructed pool can't query — which
+// made receipt validation always fail with "Unable to initialize a relay pool"
+// after an otherwise-successful zap. Apply the app's legacy .list shim (unless a
+// listEvents override supplies its own fetch path).
+export function resolveReceiptListPool(tools, overrides = {}) {
+  let pool = null;
+  try {
+    if (typeof overrides.createPool === "function") {
+      pool = overrides.createPool(tools);
+    } else if (tools && typeof tools.SimplePool === "function") {
+      pool = new tools.SimplePool();
+    }
+  } catch (error) {
+    userLogger.warn("[zapReceiptValidator] Failed to create SimplePool instance.", error);
+    return null;
+  }
+  if (
+    pool &&
+    typeof pool.list !== "function" &&
+    typeof overrides.listEvents !== "function"
+  ) {
+    try {
+      shimLegacySimplePoolMethods(pool);
+    } catch (error) {
+      userLogger.warn("[zapReceiptValidator] Failed to shim SimplePool.list.", error);
+    }
+  }
+  return pool;
+}
+
 export async function validateZapReceipt(context = {}, overrides = {}) {
   const {
     zapRequest,
@@ -330,19 +365,11 @@ export async function validateZapReceipt(context = {}, overrides = {}) {
     });
   }
 
-  let pool;
-  try {
-    if (typeof overrides.createPool === "function") {
-      pool = overrides.createPool(tools);
-    } else if (typeof tools.SimplePool === "function") {
-      pool = new tools.SimplePool();
-    }
-  } catch (error) {
-    userLogger.warn("[zapReceiptValidator] Failed to create SimplePool instance.", error);
-    pool = null;
-  }
-
-  if (!pool || typeof pool.list !== "function") {
+  const pool = resolveReceiptListPool(tools, overrides);
+  const canListEvents =
+    typeof overrides.listEvents === "function" ||
+    (pool && typeof pool.list === "function");
+  if (!pool || !canListEvents) {
     return buildValidationResult({
       status: "failed",
       reason: "Unable to initialize a relay pool for receipt validation.",

tests/zap-receipt-pool.test.mjs

@@ -0,0 +1,61 @@
+// Regression: after a successful zap, receipt validation failed with "Unable to
+// initialize a relay pool for receipt validation." nostr-tools 2.x SimplePool no
+// longer has .list(), and the validator constructed a fresh raw pool and required
+// pool.list. resolveReceiptListPool must apply the app's legacy .list shim so a
+// 2.x pool can query — and honor a listEvents override without needing .list.
+
+import "./test-helpers/setup-localstorage.mjs";
+import assert from "node:assert/strict";
+import test from "node:test";
+import { resolveReceiptListPool } from "../js/payments/zapReceiptValidator.js";
+
+// Mimics a nostr-tools 2.x SimplePool: instances have subscribeMany/close but NO
+// .list() (the method was removed in 2.x).
+function makeV2Tools() {
+  function SimplePool() {
+    this.subscribeMany = () => ({ close() {} });
+    this.querySync = async () => [];
+    this.close = () => {};
+  }
+  return { SimplePool };
+}
+
+test("a freshly constructed 2.x pool (no .list) gets the legacy .list shim", () => {
+  const tools = makeV2Tools();
+  const bare = new tools.SimplePool();
+  assert.equal(typeof bare.list, "undefined", "2.x pool starts without .list");
+
+  const pool = resolveReceiptListPool(tools, {});
+  assert.ok(pool, "a pool must be returned");
+  assert.equal(
+    typeof pool.list,
+    "function",
+    "the shim must add .list so receipt validation can query relays",
+  );
+});
+
+test("createPool override is respected and shimmed when it lacks .list", () => {
+  const created = { subscribeMany: () => ({ close() {} }), close: () => {} };
+  const pool = resolveReceiptListPool({}, { createPool: () => created });
+  assert.equal(pool, created, "must use the override-created pool");
+  assert.equal(typeof pool.list, "function", "and shim it with .list");
+});
+
+test("a listEvents override means the pool is left as-is (no shim required)", () => {
+  const created = { close: () => {} }; // no list, no subscribeMany
+  const pool = resolveReceiptListPool(
+    {},
+    { createPool: () => created, listEvents: async () => [] },
+  );
+  assert.equal(pool, created);
+  assert.equal(
+    typeof pool.list,
+    "undefined",
+    "with a listEvents override the validator uses it, so .list isn't forced",
+  );
+});
+
+test("returns null when there is no SimplePool and no override", () => {
+  const pool = resolveReceiptListPool({}, {});
+  assert.equal(pool, null);
+});