From 4fb8ad34e5826ba80e95ff20b3fb817bce485f94 Mon Sep 17 00:00:00 2001
From: Alissa Crane <alissa.crane@coinbase.com>
Date: Wed, 20 Nov 2024 13:48:13 -0800
Subject: [PATCH] add useResetFundSwapInputs utility

---
 src/swap/hooks/useResetFundSwapInputs.test.ts | 150 ++++++++++++++++++
 src/swap/hooks/useResetFundSwapInputs.ts      |  23 +++
 2 files changed, 173 insertions(+)
 create mode 100644 src/swap/hooks/useResetFundSwapInputs.test.ts
 create mode 100644 src/swap/hooks/useResetFundSwapInputs.ts

diff --git a/src/swap/hooks/useResetFundSwapInputs.test.ts b/src/swap/hooks/useResetFundSwapInputs.test.ts
new file mode 100644
index 0000000000..2fc25bccb3
--- /dev/null
+++ b/src/swap/hooks/useResetFundSwapInputs.test.ts
@@ -0,0 +1,150 @@
+import { act, renderHook } from '@testing-library/react';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { FundSwapUnit } from '../types';
+import { useResetFundSwapInputs } from './useResetFundSwapInputs';
+
+describe('useResetFundSwapInputs', () => {
+  const mockFromTokenResponse = {
+    refetch: vi.fn().mockResolvedValue(undefined),
+  };
+  const mockFromUSDCTokenResponse = {
+    refetch: vi.fn().mockResolvedValue(undefined),
+  };
+  const mockToTokenResponse = { refetch: vi.fn().mockResolvedValue(undefined) };
+  const mockFromETH: FundSwapUnit = {
+    balance: '100',
+    balanceResponse: mockFromTokenResponse,
+    amount: '50',
+    setAmount: vi.fn(),
+    setAmountUSD: vi.fn(),
+    token: undefined,
+    loading: false,
+    setLoading: vi.fn(),
+    error: undefined,
+  };
+  const mockFromUSDC: FundSwapUnit = {
+    balance: '100',
+    balanceResponse: mockFromUSDCTokenResponse,
+    amount: '50',
+    setAmount: vi.fn(),
+    setAmountUSD: vi.fn(),
+    token: undefined,
+    loading: false,
+    setLoading: vi.fn(),
+    error: undefined,
+  };
+  const mockTo: FundSwapUnit = {
+    balance: '200',
+    balanceResponse: mockToTokenResponse,
+    amount: '75',
+    setAmount: vi.fn(),
+    setAmountUSD: vi.fn(),
+    token: undefined,
+    loading: false,
+    setLoading: vi.fn(),
+    error: undefined,
+  };
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it('should return a function', () => {
+    const { result } = renderHook(() =>
+      useResetFundSwapInputs({
+        fromETH: mockFromETH,
+        fromUSDC: mockFromUSDC,
+        to: mockTo,
+      }),
+    );
+    expect(typeof result.current).toBe('function');
+  });
+
+  it('should call refetch on responses and set amounts to empty strings when executed', async () => {
+    const { result } = renderHook(() =>
+      useResetFundSwapInputs({
+        fromETH: mockFromETH,
+        fromUSDC: mockFromUSDC,
+        to: mockTo,
+      }),
+    );
+    await act(async () => {
+      await result.current();
+    });
+    expect(mockFromTokenResponse.refetch).toHaveBeenCalledTimes(1);
+    expect(mockToTokenResponse.refetch).toHaveBeenCalledTimes(1);
+    expect(mockFromETH.setAmount).toHaveBeenCalledWith('');
+    expect(mockFromETH.setAmountUSD).toHaveBeenCalledWith('');
+    expect(mockTo.setAmount).toHaveBeenCalledWith('');
+    expect(mockTo.setAmountUSD).toHaveBeenCalledWith('');
+  });
+
+  it("should not create a new function reference if from and to haven't changed", () => {
+    const { result, rerender } = renderHook(() =>
+      useResetFundSwapInputs({
+        fromETH: mockFromETH,
+        fromUSDC: mockFromUSDC,
+        to: mockTo,
+      }),
+    );
+    const firstRender = result.current;
+    rerender();
+    expect(result.current).toBe(firstRender);
+  });
+
+  it('should create a new function reference if from or to change', () => {
+    const { result, rerender } = renderHook(
+      ({ fromETH, fromUSDC, to }) =>
+        useResetFundSwapInputs({
+          fromETH,
+          fromUSDC,
+          to,
+        }),
+      {
+        initialProps: {
+          fromETH: mockFromETH,
+          fromUSDC: mockFromUSDC,
+          to: mockTo,
+        },
+      },
+    );
+    const firstRender = result.current;
+    const newMockFromETH = {
+      ...mockFromETH,
+      balanceResponse: { refetch: vi.fn().mockResolvedValue(undefined) },
+    };
+    const newMockFromUSDC = {
+      ...mockFromUSDC,
+      balanceResponse: { refetch: vi.fn().mockResolvedValue(undefined) },
+    };
+    rerender({
+      fromETH: newMockFromETH,
+      fromUSDC: newMockFromUSDC,
+      to: mockTo,
+    });
+    expect(result.current).not.toBe(firstRender);
+  });
+
+  it('should handle null responses gracefully', async () => {
+    const mockFromWithNullResponse = { ...mockFromETH, balanceResponse: null };
+    const mockFromUSDCWithNullResponse = {
+      ...mockFromUSDC,
+      balanceResponse: null,
+    };
+    const mockToWithNullResponse = { ...mockTo, balanceResponse: null };
+    const { result } = renderHook(() =>
+      useResetFundSwapInputs({
+        fromETH: mockFromWithNullResponse,
+        fromUSDC: mockFromUSDCWithNullResponse,
+        to: mockToWithNullResponse,
+      }),
+    );
+    await act(async () => {
+      await result.current();
+    });
+    expect(mockFromWithNullResponse.setAmount).toHaveBeenCalledWith('');
+    expect(mockFromWithNullResponse.setAmountUSD).toHaveBeenCalledWith('');
+    expect(mockToWithNullResponse.setAmount).toHaveBeenCalledWith('');
+    expect(mockToWithNullResponse.setAmountUSD).toHaveBeenCalledWith('');
+  });
+});
diff --git a/src/swap/hooks/useResetFundSwapInputs.ts b/src/swap/hooks/useResetFundSwapInputs.ts
new file mode 100644
index 0000000000..26f7af2935
--- /dev/null
+++ b/src/swap/hooks/useResetFundSwapInputs.ts
@@ -0,0 +1,23 @@
+import { useCallback } from 'react';
+import type { FundSwapTokens } from '../types';
+
+// Refreshes balances and inputs post-swap
+export const useResetFundSwapInputs = ({
+  fromETH,
+  fromUSDC,
+  to,
+}: FundSwapTokens) => {
+  return useCallback(async () => {
+    await Promise.all([
+      fromETH.balanceResponse?.refetch(),
+      fromUSDC.balanceResponse?.refetch(),
+      to.balanceResponse?.refetch(),
+      fromETH.setAmount(''),
+      fromUSDC.setAmount(''),
+      fromETH.setAmountUSD(''),
+      fromUSDC.setAmountUSD(''),
+      to.setAmount(''),
+      to.setAmountUSD(''),
+    ]);
+  }, [fromETH, fromUSDC, to]);
+};