From 4f987d5ea98676463ba532e45631f83a85724523 Mon Sep 17 00:00:00 2001
From: Rasmus Porsager <rasmus@porsager.com>
Date: Wed, 8 Mar 2023 22:45:14 +0100
Subject: [PATCH] Ensure queries are not pushed on connections with active
 cursors - fixes #411

---
 src/connection.js |  1 +
 tests/index.js    | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/src/connection.js b/src/connection.js
index 4427f13d..b3d25e72 100644
--- a/src/connection.js
+++ b/src/connection.js
@@ -166,6 +166,7 @@ function Connection(options, queues = {}, { onopen = noop, onend = noop, onclose
       build(q)
       return write(toBuffer(q))
         && !q.describeFirst
+        && !q.cursorFn
         && sent.length < max_pipeline
         && (!q.options.onexecute || q.options.onexecute(connection))
     } catch (error) {
diff --git a/tests/index.js b/tests/index.js
index 9c4ab427..f59c641b 100644
--- a/tests/index.js
+++ b/tests/index.js
@@ -2472,3 +2472,24 @@ t('Insert array with undefined transform', async() => {
     await sql`drop table test`
   ]
 })
+
+t('concurrent cursors', async() => {
+  const xs = []
+
+  await Promise.all([...Array(7)].map((x, i) => [
+    sql`select ${ i }::int as a, generate_series(1, 2) as x`.cursor(([x]) => xs.push(x.a + x.x))
+  ]).flat())
+
+  return ['12233445566778', xs.join('')]
+})
+
+t('concurrent cursors multiple connections', async() => {
+  const sql = postgres({ ...options, max: 2 })
+  const xs = []
+
+  await Promise.all([...Array(7)].map((x, i) => [
+    sql`select ${ i }::int as a, generate_series(1, 2) as x`.cursor(([x]) => xs.push(x.a + x.x))
+  ]).flat())
+
+  return ['12233445566778', xs.sort().join('')]
+})