From ce338dc88fc81678e987c5f5fd900abd1cf6cfef Mon Sep 17 00:00:00 2001
From: Rusty Russell <rusty@rustcorp.com.au>
Date: Wed, 21 Jul 2021 15:08:14 +0930
Subject: [PATCH] offerout: don't insist that invoice vendor match our vendor.

This was a bug in the spec, actually.

Reported-by: @shesek
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Fixes: #4666
---
 plugins/offers_inv_hook.c |  4 ----
 tests/test_pay.py         | 21 +++++++++++++++++++++
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/plugins/offers_inv_hook.c b/plugins/offers_inv_hook.c
index 1752f78e1..caba93f69 100644
--- a/plugins/offers_inv_hook.c
+++ b/plugins/offers_inv_hook.c
@@ -229,15 +229,11 @@ static struct command_result *listoffers_done(struct command *cmd,
 	 *   or unset exactly as they are in the `offer`:
 	 *   - `refund_for`
 	 *   - `description`
-	 *   - `vendor`
 	 */
 	err = inv_must_equal_offer(cmd, inv, refund_for);
 	if (err)
 		return err;
 	err = inv_must_equal_offer(cmd, inv, description);
-	if (err)
-		return err;
-	err = inv_must_equal_offer(cmd, inv, vendor);
 	if (err)
 		return err;
 
diff --git a/tests/test_pay.py b/tests/test_pay.py
index 678810885..8108b67c4 100644
--- a/tests/test_pay.py
+++ b/tests/test_pay.py
@@ -4452,6 +4452,27 @@ def test_sendinvoice(node_factory, bitcoind):
                                 'label': 'test sendinvoice refund'})
     wait_for(lambda: only_one(l2.rpc.call('listoffers', [refund['offer_id']])['offers'])['used'] is True)
 
+    # Offer with vendor: we must not copy vendor into our invoice!
+    offer = l1.rpc.call('offerout', {'amount': '10000sat',
+                                     'description': 'simple test',
+                                     'vendor': "clightning test suite"})
+
+    out = l2.rpc.call('sendinvoice', {'offer': offer['bolt12'],
+                                      'label': 'test sendinvoice 3'})
+    assert out['label'] == 'test sendinvoice 3'
+    assert out['description'] == 'simple test'
+    assert 'vendor' not in out
+    assert 'bolt12' in out
+    assert 'payment_hash' in out
+    assert out['status'] == 'paid'
+    assert 'payment_preimage' in out
+    assert 'expires_at' in out
+    assert out['msatoshi'] == 10000000
+    assert out['amount_msat'] == Millisatoshi(10000000)
+    assert 'pay_index' in out
+    assert out['msatoshi_received'] == 10000000
+    assert out['amount_received_msat'] == Millisatoshi(10000000)
+
 
 def test_self_pay(node_factory):
     """Repro test for issue 4345: pay ourselves via the pay plugin.