add more tests. now at 98% coverage.

Tests/Fakes/FakeLayout.swift

@@ -16,7 +16,8 @@ import Foundation
 import UIKit
 
 extension UICollectionViewCompositionalLayout {
- static func fakeLayout(useNibViews: Bool = false) -> UICollectionViewCompositionalLayout {
+ static func fakeLayout(addSupplementaryViews: Bool = true,
+ useNibViews: Bool = false) -> UICollectionViewCompositionalLayout {
  let fractionalWidth = CGFloat(0.5)
 
  // Supplementary Item
@@ -37,7 +38,10 @@ extension UICollectionViewCompositionalLayout {
  // Item
  let itemSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(fractionalWidth),
  heightDimension: .fractionalHeight(1))
- let item = NSCollectionLayoutItem(layoutSize: itemSize, supplementaryItems: [view])
+ let item = NSCollectionLayoutItem(
+ layoutSize: itemSize,
+ supplementaryItems: addSupplementaryViews ? [view] : []
+ )
 
  // Group
  let groupSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1),

Tests/Fakes/FakeSupplementaryViewModel.swift

@@ -49,7 +49,7 @@ final class FakeSupplementaryView: UICollectionViewCell { }
 struct FakeHeaderViewModel: SupplementaryHeaderViewModel {
  let title = String.random
 
- nonisolated var id: UniqueIdentifier { self.title }
+ nonisolated var id: UniqueIdentifier { "Header" }
 
  var expectationConfigureView: XCTestExpectation?
  func configure(view: FakeCollectionHeaderView) {
@@ -70,7 +70,7 @@ final class FakeCollectionHeaderView: UICollectionReusableView { }
 struct FakeFooterViewModel: SupplementaryFooterViewModel {
  let title = String.random
 
- nonisolated var id: UniqueIdentifier { self.title }
+ nonisolated var id: UniqueIdentifier { "Footer" }
 
  var expectationConfigureView: XCTestExpectation?
  func configure(view: FakeCollectionFooterView) {

Tests/TestCollectionViewDriverReconfigure.swift

@@ -48,6 +48,39 @@ final class TestCollectionViewDriverReconfigure: UnitTestCase {
 
  self.keepDriverAlive(driver)
  }
+
+ @MainActor
+ func test_reconfigure_header_footer() {
+ let viewController = FakeCollectionViewController()
+ viewController.collectionView.setCollectionViewLayout(
+ UICollectionViewCompositionalLayout.fakeLayout(addSupplementaryViews: false),
+ animated: false
+ )
+
+ let driver = CollectionViewDriver(view: viewController.collectionView, options: .test())
+
+ // Initial header and footer
+ let header = FakeHeaderViewModel(expectationConfigureView: self.expectation(name: "initial_header"))
+ let footer = FakeFooterViewModel(expectationConfigureView: self.expectation(name: "initial_footer"))
+ let cells = [FakeNumberCellViewModel()]
+ let section = SectionViewModel(id: "id", cells: cells, header: header, footer: footer)
+ let model = CollectionViewModel(id: "id", sections: [section])
+
+ driver.update(viewModel: model)
+ self.simulateAppearance(viewController: viewController)
+ self.waitForExpectations()
+
+ // Update header and footer to be reconfigured
+ let updatedHeader = FakeHeaderViewModel(expectationConfigureView: self.expectation(name: "updated_header"))
+ let updatedFooter = FakeFooterViewModel(expectationConfigureView: self.expectation(name: "updated_footer"))
+ let updatedSection = SectionViewModel(id: "id", cells: cells, header: updatedHeader, footer: updatedFooter)
+ let updatedModel = CollectionViewModel(id: "id", sections: [updatedSection])
+
+ driver.update(viewModel: updatedModel)
+ self.waitForExpectations()
+
+ self.keepDriverAlive(driver)
+ }
 }
 
 private struct MyStaticCellViewModel: CellViewModel {