test: stabilize LND regtests for expanded topology

Author: a1denvalu3

.github/workflows/regtest-mint.yml

@@ -26,7 +26,7 @@ jobs:
   regtest-mint:
     runs-on: ${{ inputs.os-version }}
     # Spark's cold source build can take 90 minutes before the suite starts.
-    timeout-minutes: ${{ inputs.backend-wallet-class == 'SparkL2Wallet' && 150 || 30 }}
+    timeout-minutes: ${{ inputs.backend-wallet-class == 'SparkL2Wallet' && 150 || 45 }}
     env:
       CASHU_REGTEST_DIR: ${{ github.workspace }}/regtest
     steps:
@@ -55,7 +55,7 @@ jobs:
         run: make test-spark-backend-regtest
 
       - name: Run Tests
-        timeout-minutes: ${{ inputs.backend-wallet-class == 'SparkL2Wallet' && 45 || 10 }}
+        timeout-minutes: ${{ inputs.backend-wallet-class == 'SparkL2Wallet' && 45 || 20 }}
         env:
           WALLET_NAME: test_wallet
           MINT_HOST: localhost

tests/helpers.py

@@ -264,6 +264,24 @@ def get_real_invoice_routed(sats: int) -> str:
     return run_cmd_json(cmd)["payment_request"]
 
 
+def get_real_invoice_fee_leaf(sats: int) -> str:
+    """Invoice from isolated lnd-4, reachable only through the fee hub."""
+    cmd = [
+        "docker",
+        "exec",
+        "cashu-lnd-4-1",
+        "lncli",
+        "--network=regtest",
+        "--rpcserver=lnd-4:10009",
+    ]
+    destination = run_cmd_json([*cmd, "getinfo"])["identity_pubkey"]
+    _wait_for_route(
+        [*docker_lightning_mint_cli, "queryroutes", "--dest", destination, "--amt", str(sats)],
+        "routes",
+    )
+    return run_cmd_json([*cmd, "addinvoice", str(sats)])["payment_request"]
+
+
 async def pay_if_regtest(bolt11: str) -> None:
     if is_spark_backend and os.getenv("CASHU_SPARK_REGTEST", "").lower() == "true":
         from tests.spark_regtest import pay_regtest_invoice

tests/mint/test_mint_api.py

@@ -3,7 +3,7 @@
 import pytest
 import pytest_asyncio
 
-from cashu.core.base import MeltQuoteState, MintQuoteState
+from cashu.core.base import MeltQuoteState, Method, MintQuoteState, Unit
 from cashu.core.models import (
     GetInfoResponse,
     MintMethodSetting,
@@ -21,6 +21,7 @@
 from cashu.wallet.wallet import Wallet
 from tests.helpers import (
     get_real_invoice,
+    get_real_invoice_fee_leaf,
     get_real_invoice_routed,
     is_cln_backend,
     is_fake,
@@ -89,7 +90,11 @@ async def test_api_keys(ledger: Ledger):
             for keyset in ledger.keysets.values()
         ]
     }
-    assert response.json() == expected
+    result = response.json()
+    # PostgreSQL can return the same keysets in a different order.
+    result["keysets"].sort(key=lambda keyset: keyset["id"])
+    expected["keysets"].sort(key=lambda keyset: keyset["id"])
+    assert result == expected
 
 
 @pytest.mark.asyncio
@@ -569,8 +574,8 @@ async def test_melt_external_routing_fee_rounding(ledger: Ledger, wallet: Wallet
     await wallet.mint(1024, quote_id=mint_quote.quote)
     assert wallet.balance == 1024
 
-    # external invoice that the mint can only pay through a routing node
-    invoice_payment_request = get_real_invoice_routed(1000)
+    # The isolated fee leaf prevents LDK from offering a cheaper, whole-sat route.
+    invoice_payment_request = get_real_invoice_fee_leaf(1000)
 
     quote = await wallet.melt_quote(invoice_payment_request)
     assert quote.amount == 1000
@@ -599,15 +604,23 @@ async def test_melt_external_routing_fee_rounding(ledger: Ledger, wallet: Wallet
     resp_quote = PostMeltQuoteResponse(**response.json())
     assert resp_quote.state == MeltQuoteState.paid.value
 
-    # the routing fee for 1000 sat is 1001 msat (1000 msat base fee + 1 ppm)
-    # which the mint must round up to 2 sat when it accounts the fee
     melt_quote = await ledger.crud.get_melt_quote(quote_id=quote.quote, db=ledger.db)
     assert melt_quote, "No melt quote in db"
-    assert melt_quote.fee_paid == 2, "Fee not rounded up to the next sat"
+
+    # Verify rounding against LND's settled fee, independently of path selection.
+    payment = await ledger.backends[Method.bolt11][Unit.sat].get_payment_status(
+        melt_quote.checking_id
+    )
+    assert payment.settled
+    assert payment.fee is not None and payment.fee.unit == Unit.msat
+    whole_sats, remainder_msat = divmod(payment.fee.amount, 1000)
+    assert remainder_msat > 0, "Route must charge a fractional sat to test rounding"
+    rounded_fee = whole_sats + 1
+    assert melt_quote.fee_paid == rounded_fee, "Fee not rounded up to the next sat"
 
     # we get back the fee reserve minus the rounded up fee
     change_sat = sum([c.amount for c in resp_quote.change or []])
-    assert change_sat == 18, "Wrong change returned"
+    assert change_sat == quote.fee_reserve - rounded_fee, "Wrong change returned"
 
 
 @pytest.mark.asyncio