Fix reusing collection views among multiple adapters

Instagram · May 9, 2017 · f829ba7 · f829ba7
1 parent 034f162
commit f829ba7
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Showing 2 changed files with 35 additions and 0 deletions.
diff --git a/Source/IGListAdapter.m b/Source/IGListAdapter.m
@@ -81,6 +81,7 @@ - (void)setCollectionView:(UICollectionView *)collectionView {
         if (globalCollectionViewAdapterMap == nil) {
             globalCollectionViewAdapterMap = [NSMapTable weakToWeakObjectsMapTable];
         }
+        [globalCollectionViewAdapterMap removeObjectForKey:_collectionView];
         [[globalCollectionViewAdapterMap objectForKey:collectionView] setCollectionView:nil];
         [globalCollectionViewAdapterMap setObject:self forKey:collectionView];
 

diff --git a/Tests/IGListAdapterTests.m b/Tests/IGListAdapterTests.m
@@ -1214,4 +1214,38 @@ - (void)test_withStrongRefToSectionController_thatAdapterSectionIndexIsZero_that
     XCTAssertEqual([wAdapter sectionForSectionController:sc], 0);
 }
 
+- (void)test_whenSwappingCollectionViews_withMultipleAdapters_thatDoesntNilOtherAdaptersCollectionView {
+    IGListTestAdapterDataSource *dataSource1 = [IGListTestAdapterDataSource new];
+    IGListAdapter *adapter1 = [[IGListAdapter alloc] initWithUpdater:[IGListAdapterUpdater new] viewController:nil];
+    adapter1.dataSource = dataSource1;
+
+    IGListTestAdapterDataSource *dataSource2 = [IGListTestAdapterDataSource new];
+    IGListAdapter *adapter2 = [[IGListAdapter alloc] initWithUpdater:[IGListAdapterUpdater new] viewController:nil];
+    adapter2.dataSource = dataSource2;
+
+    UICollectionView *collectionView1 = [[UICollectionView alloc] initWithFrame:CGRectZero collectionViewLayout:[UICollectionViewFlowLayout new]];
+    UICollectionView *collectionView2 = [[UICollectionView alloc] initWithFrame:CGRectZero collectionViewLayout:[UICollectionViewFlowLayout new]];
+
+    adapter1.collectionView = collectionView1;
+    adapter2.collectionView = collectionView2;
+
+    XCTAssertEqual(adapter1.collectionView, collectionView1);
+    XCTAssertEqual(collectionView1.dataSource, adapter1);
+    XCTAssertEqual(adapter2.collectionView, collectionView2);
+    XCTAssertEqual(collectionView2.dataSource, adapter2);
+
+    adapter2.collectionView = collectionView1;
+
+    XCTAssertEqual(adapter2.collectionView, collectionView1);
+    XCTAssertEqual(collectionView1.dataSource, adapter2);
+    XCTAssertNil(adapter1.collectionView);
+
+    adapter1.collectionView = collectionView2;
+
+    XCTAssertEqual(adapter1.collectionView, collectionView2);
+    XCTAssertEqual(collectionView2.dataSource, adapter1);
+    XCTAssertEqual(adapter2.collectionView, collectionView1);
+    XCTAssertEqual(collectionView1.dataSource, adapter2);
+}
+
 @end