taler-typescript-core

commit 9d1a5a06c40c63481555959ca79beee57771e0e7
parent ec559f2064a4fa8a9b2b4473d9db58ff27a54a39
Author: Florian Dold <dold@taler.net>
Date:   Thu, 20 Aug 2026 19:06:45 +0200

wallet-core: respect instructed conversion inventory

Diffstat:
M
packages/taler-wallet-core/src/instructedAmountConversion.test.ts
 | 
39
+++++++++++++++++++++++++++++++++++++++
M
packages/taler-wallet-core/src/instructedAmountConversion.ts
 | 
53
++++++++++++++++++++++++++++++++++++++---------------

2 files changed, 77 insertions(+), 15 deletions(-)
diff --git a/packages/taler-wallet-core/src/instructedAmountConversion.test.ts b/packages/taler-wallet-core/src/instructedAmountConversion.test.ts
@@ -620,3 +620,42 @@ test("demo: withdraw raw 13", (t) => {
   //current wallet impl: hides the left in reserve fee
   //shows fee = 0.2
 });
+
+test("deposit refresh search does not reuse an exhausted denomination", () => {
+  const onlyCoin = defaultFeeConfig(kudos`2`, 1);
+  const result = convertDepositAmountForAvailableCoins(
+    { list: [onlyCoin], exchanges: {} },
+    kudos`3`,
+    TransactionAmountMode.Effective,
+  );
+
+  assert.strictEqual(Amounts.stringifyValue(result.effective), "2");
+  assert.strictEqual(result.refresh, undefined);
+});
+
+test("zero-fee denominations rank ahead of fee-bearing denominations", () => {
+  const paid = {
+    ...defaultFeeConfig(kudos`2`, 1),
+    id: "paid",
+  };
+  const free = {
+    ...defaultFeeConfig(kudos`2`, 1),
+    id: "free",
+    denomDeposit: kudos`0`,
+    denomWithdraw: kudos`0`,
+  };
+
+  const deposit = convertDepositAmountForAvailableCoins(
+    { list: [paid, free], exchanges: {} },
+    kudos`2`,
+    TransactionAmountMode.Effective,
+  );
+  assert.strictEqual(Amounts.stringifyValue(deposit.raw), "2");
+
+  const withdrawal = convertWithdrawalAmountFromAvailableCoins(
+    { list: [paid, free], exchanges: {} },
+    kudos`2`,
+    TransactionAmountMode.Effective,
+  );
+  assert.strictEqual(Amounts.stringifyValue(withdrawal.raw), "2");
+});
diff --git a/packages/taler-wallet-core/src/instructedAmountConversion.ts b/packages/taler-wallet-core/src/instructedAmountConversion.ts
@@ -476,6 +476,12 @@ function searchBestRefreshCoin(
   let refreshIdx = 0;
   refreshIteration: while (refreshIdx < depositDenoms.length) {
     const d = depositDenoms[refreshIdx];
+    if (d.total <= 0) {
+      // The initial deposit selection consumes from this same inventory.
+      // Do not manufacture another input coin for the refresh leg.
+      refreshIdx++;
+      continue refreshIteration;
+    }
 
     const denomContribution =
       mode === TransactionAmountMode.Effective
@@ -547,6 +553,26 @@ function searchBestRefreshCoin(
   return choice;
 }
 
+/** Sort higher value-per-fee ratios first, with a zero fee as the optimum. */
+function compareValuePerFee(
+  value1: AmountJson,
+  fee1: AmountJson,
+  value2: AmountJson,
+  fee2: AmountJson,
+): number {
+  const fee1Zero = Amounts.isZero(fee1);
+  const fee2Zero = Amounts.isZero(fee2);
+  if (fee1Zero !== fee2Zero) {
+    return fee1Zero ? -1 : 1;
+  }
+  if (fee1Zero) {
+    return 0;
+  }
+  const rate1 = Amounts.divmod(value1, fee1).quotient;
+  const rate2 = Amounts.divmod(value2, fee2).quotient;
+  return rate1 === rate2 ? 0 : rate1 < rate2 ? 1 : -1;
+}
+
 /**
  * Returns a copy of the list sorted for the best denom to withdraw first
  */
@@ -565,13 +591,12 @@ function rankDenominationForWithdrawals(
     //ranking should take the relative contribution in the exchange
     //which is (value - denomFee / fixedFee)
 
-    const rate1 = Amounts.isZero(d1.denomWithdraw)
-      ? Number.MIN_SAFE_INTEGER
-      : Amounts.divmod(d1.value, d1.denomWithdraw).quotient;
-    const rate2 = Amounts.isZero(d2.denomWithdraw)
-      ? Number.MIN_SAFE_INTEGER
-      : Amounts.divmod(d2.value, d2.denomWithdraw).quotient;
-    const contribCmp = rate1 === rate2 ? 0 : rate1 < rate2 ? 1 : -1;
+    const contribCmp = compareValuePerFee(
+      d1.value,
+      d1.denomWithdraw,
+      d2.value,
+      d2.denomWithdraw,
+    );
     return (
       contribCmp ||
       Duration.cmp(d1.duration, d2.duration) ||
@@ -623,14 +648,12 @@ function rankDenominationForDeposit(
     // different exchanges may have different wireFee
     // ranking should take the relative contribution in the exchange
     // which is (value - denomFee / fixedFee)
-    const rate1 = Amounts.isZero(d1.denomDeposit)
-      ? Number.MIN_SAFE_INTEGER
-      : Amounts.divmod(d1.value, d1.denomDeposit).quotient;
-    const rate2 = Amounts.isZero(d2.denomDeposit)
-      ? Number.MIN_SAFE_INTEGER
-      : Amounts.divmod(d2.value, d2.denomDeposit).quotient;
-
-    const contribCmp = rate1 === rate2 ? 0 : rate1 < rate2 ? 1 : -1;
+    const contribCmp = compareValuePerFee(
+      d1.value,
+      d1.denomDeposit,
+      d2.value,
+      d2.denomDeposit,
+    );
     return (
       contribCmp ||
       Duration.cmp(d1.duration, d2.duration) ||