From 5bb6140858512a5dd3546c73aae4478fed74229d Mon Sep 17 00:00:00 2001
From: James Hardwick <james.hardwick@immutable.com>
Date: Thu, 16 May 2024 14:55:04 +1000
Subject: [PATCH] Show fee as 0% if no fees returned in quote.

---
 .../swap/functions/swapConversionRate.test.ts | 47 +++++++++++++++++++
 .../swap/functions/swapConversionRate.ts      |  2 +-
 2 files changed, 48 insertions(+), 1 deletion(-)

diff --git a/packages/checkout/widgets-lib/src/widgets/swap/functions/swapConversionRate.test.ts b/packages/checkout/widgets-lib/src/widgets/swap/functions/swapConversionRate.test.ts
index f21297f926..21afe1277f 100644
--- a/packages/checkout/widgets-lib/src/widgets/swap/functions/swapConversionRate.test.ts
+++ b/packages/checkout/widgets-lib/src/widgets/swap/functions/swapConversionRate.test.ts
@@ -133,4 +133,51 @@ describe('formatQuoteConversionRate', () => {
       fee: 1,
     });
   });
+
+  it('should handle an empty fee array', () => {
+    const fromAmount = '1.50';
+    const fromToken = {
+      name: 'ETH',
+      symbol: 'ETH',
+      address: '0x123',
+      chainId: 1,
+      decimals: 18,
+    } as TokenInfo;
+    const mockQuote = {
+      quote: {
+        amount: {
+          value: BigNumber.from('2000000000000000000'),
+          token: {
+            symbol: 'DAI',
+            address: '0x456',
+            chainId: 1,
+            decimals: 18,
+          },
+        } as Amount,
+        amountWithMaxSlippage: {} as Amount,
+        slippage: 0,
+        fees: [],
+      } as Quote,
+      swap: {
+        gasFeeEstimate: {
+          value: BigNumber.from(100),
+        },
+      },
+      approval: {
+        gasFeeEstimate: {
+          value: BigNumber.from(50),
+        },
+      },
+    } as TransactionResponse;
+    const labelKey = 'conversion.label';
+
+    formatQuoteConversionRate(fromAmount, fromToken, mockQuote, labelKey, mockTranslate as unknown as TFunction);
+
+    expect(mockTranslate).toHaveBeenCalledWith(labelKey, {
+      fromSymbol: 'ETH',
+      toSymbol: 'DAI',
+      rate: '1.33',
+      fee: 0,
+    });
+  });
 });
diff --git a/packages/checkout/widgets-lib/src/widgets/swap/functions/swapConversionRate.ts b/packages/checkout/widgets-lib/src/widgets/swap/functions/swapConversionRate.ts
index 2e1df2a2af..e02f5760d6 100644
--- a/packages/checkout/widgets-lib/src/widgets/swap/functions/swapConversionRate.ts
+++ b/packages/checkout/widgets-lib/src/widgets/swap/functions/swapConversionRate.ts
@@ -54,6 +54,6 @@ export const formatQuoteConversionRate = (
     fromSymbol: fromToken.symbol,
     toSymbol: toToken.symbol,
     rate: formattedConversion,
-    fee: secondaryFee.basisPoints / 100,
+    fee: (secondaryFee?.basisPoints ?? 0) / 100,
   });
 };