old_contents: import React, { useContext } from 'react';
  import { render, act, screen, cleanup } from '@testing-library/react';
  import { AuthContext, AuthProvider } from './index';
  
  jest.useFakeTimers();
  
  // Mock the the Firebase Auth onAuthStateChanged function, which pauses for 1
  // second before returning a fake user with only a name field set.
  const mockOnAuthStateChanged = jest.fn(cb => {
    setTimeout(() => {
      cb({ name: 'Keiffer' })
    }, 1000);
  });
  jest.mock('firebase/app', () => {
    return {
      initializeApp: () => {
        return {
          auth: () => {
            return {
              onAuthStateChanged: mockOnAuthStateChanged
            }
          }
        }
      }
    }
  });
  
  describe('AuthProvider component', () => {
    beforeEach(() => {
      render(<AuthProvider />);
    });
  
    afterEach(() => {
      cleanup();
    });
  
    it('initially displays "Loading"', () => {
      act(() => jest.advanceTimersByTime(500));
      expect(screen.getByText('Loading...')).toBeInTheDocument();
    });
  
    it('returns a provider when onAuthStateChanged is called', () => {
      act(() => jest.advanceTimersByTime(2000));
      expect(screen.queryByText('Loading...')).not.toBeInTheDocument();
    });
  });
  
  describe('AuthContext Consumer component', () => {
    // A Consumer component for AuthContext that just displays the current
    // user.
    const TestAuthContextConsumerComponent = () => {
      const {currentUser} = useContext(AuthContext);
  
      return (
        <div>
          <div>{currentUser.name}</div>
        </div>
      );
    }
  
    beforeEach(() => {
      render(
        <AuthProvider>
          <TestAuthContextConsumerComponent />
        </AuthProvider>
      );
    })
  
    afterEach(() => {
      cleanup();
    })
  
    it('initially displays "Loading"', () => {
      act(() => jest.advanceTimersByTime(500));
      expect(screen.getByText('Loading...')).toBeInTheDocument();
    });
  
    it('displays the current user when they are authenticated', () => {
      act(() => jest.advanceTimersByTime(2000));
      expect(screen.getByText('Keiffer')).toBeInTheDocument();
    })
  });
  
new_contents: import React, { useContext } from 'react';
  import { render, act, screen, cleanup } from '@testing-library/react';
  import { AuthContext, AuthProvider } from './index';
  
  jest.useFakeTimers();
  
  // Mock the the Firebase Auth onAuthStateChanged function, which pauses for 1
  // second before returning a fake user with only a name field set.
  const mockOnAuthStateChanged = jest.fn(callback => {
    setTimeout(() => {
      callback({ name: 'Keiffer' })
    }, 1000);
  });
  jest.mock('firebase/app', () => {
    return {
      initializeApp: () => {
        return {
          auth: () => {
            return {
              onAuthStateChanged: mockOnAuthStateChanged
            }
          }
        }
      }
    }
  });
  
  describe('AuthProvider component', () => {
    beforeEach(() => {
      render(<AuthProvider />);
    });
  
    afterEach(() => {
      cleanup();
    });
  
    it('initially displays "Loading"', () => {
      act(() => jest.advanceTimersByTime(500));
      expect(screen.getByText('Loading...')).toBeInTheDocument();
    });
  
    it('returns a provider when onAuthStateChanged is called', () => {
      act(() => jest.advanceTimersByTime(2000));
      expect(screen.queryByText('Loading...')).not.toBeInTheDocument();
    });
  });
  
  describe('AuthContext Consumer component', () => {
    // A Consumer component for AuthContext that just displays the current
    // user.
    const TestAuthContextConsumerComponent = () => {
      const {currentUser} = useContext(AuthContext);
  
      return (
        <div>
          <div>{currentUser.name}</div>
        </div>
      );
    }
  
    beforeEach(() => {
      render(
        <AuthProvider>
          <TestAuthContextConsumerComponent />
        </AuthProvider>
      );
    })
  
    afterEach(() => {
      cleanup();
    })
  
    it('initially displays "Loading"', () => {
      act(() => jest.advanceTimersByTime(500));
      expect(screen.getByText('Loading...')).toBeInTheDocument();
    });
  
    it('displays the current user when they are authenticated', () => {
      act(() => jest.advanceTimersByTime(2000));
      expect(screen.getByText('Keiffer')).toBeInTheDocument();
    })
  });
  
subject: Clarify variable