Add IGListAdapterDelegate Methods 3/n

Summary:
## CONTEXT
`IGListAdapterDelegate` currently has methods that are fired when an object is *first* displayed and when an object *ended* display on screen.  For many use cases this works but there are use cases in which it would be helpful to know whenever a cell will be displayed or ends display.  This is especially relevant in the `IGListAdapterDelegateAnnouncer` which will enable you to add code for tracking cells globally.  This change also balances the `IGListAdapterDelegate` with `IGListDisplayDelegate`  which has methods which include the cell as well

## PLAN
This diff will be go out in multiple parts
- delegate method addition (many file change due to our pattern of not preferring default implementation of protocol methods)
- Update to `IGListDisplayHandler` and `IGListAdapterDelegateAnnouncer` for invocation of delegate methods
- Unit test additions

## THIS DIFF
This diff updates the unit tests of `IGListAdapterDelegateAnnouncerTests`, `IGListAdapterE2ETests` and `IGListDisplayHandlerTests`.  We added new expectations and to existing unit tests because the functionality to confirm is already tested it was just only checking the existing delegate methods.  The new tests check the new methods as well

Reviewed By: maxolls

Differential Revision: D70406065

fbshipit-source-id: ee054a21f0709b14081fdff38e22ab9710222794

Author: Jesse Seidman

Tests/IGListAdapterDelegateAnnouncerTests.m

@@ -4,7 +4,6 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  */
-
 #import <XCTest/XCTest.h>
 
 #import <OCMock/OCMock.h>
@@ -17,6 +16,7 @@
 #import "IGTestDelegateDataSource.h"
 #import "IGTestObject.h"
 #import "IGListAdapterDelegateAnnouncer.h"
+#import "IGTestCell.h"
 
 @interface IGListAdapterDelegateAnnouncerTests : XCTestCase
 
@@ -27,6 +27,7 @@ @interface IGListAdapterDelegateAnnouncerTests : XCTestCase
 
 @property (nonatomic, strong) UICollectionView *collectionView1;
 @property (nonatomic, strong) UICollectionView *collectionView2;
+
 @property (nonatomic, strong) id<IGListTestCaseDataSource> dataSource1;
 @property (nonatomic, strong) id<IGListTestCaseDataSource> dataSource2;
 @property (nonatomic, strong) IGListAdapter *adapter1;
@@ -48,13 +49,16 @@ - (void)setUp {
 
     self.collectionView2 = [[UICollectionView alloc] initWithFrame:self.window.bounds collectionViewLayout:[UICollectionViewFlowLayout new]];
     [self.window addSubview:self.collectionView2];
-    
-    self.dataSource1 = [IGTestDelegateDataSource new];
-    self.dataSource2 = [IGTestDelegateDataSource new];
+
+    IGTestDelegateDataSource *const dataSource1 = [IGTestDelegateDataSource new];
+    self.dataSource1 = dataSource1;
+
+    IGTestDelegateDataSource *const dataSource2 = [IGTestDelegateDataSource new];
+    self.dataSource2 = dataSource2;
 
     self.adapter1 = [[IGListAdapter alloc] initWithUpdater:[IGListAdapterUpdater new] viewController:self.viewController];
     self.adapter1.globalDelegateAnnouncer = self.announcer;
-    
+
     self.adapter2 = [[IGListAdapter alloc] initWithUpdater:[IGListAdapterUpdater new] viewController:self.viewController];
     self.adapter2.globalDelegateAnnouncer = self.announcer;
 }
@@ -77,19 +81,23 @@ - (void)setupAdapter2WithObjects:(NSArray *)objects {
 
 - (void)test_whenShowingOneItem_withTwoListeners_withOneAdapter_thatBothListenersReceivesWillDisplay{
     [self setupAdapter1WithObjects:@[]];
-    
+
     IGTestObject *const object = genTestObject(@1, @1);
     self.dataSource1.objects = @[
         object
     ];
 
+    NSIndexPath *const indexPath = [NSIndexPath indexPathForItem:0 inSection:0];
+
     id mockDisplayHandler1 = [OCMockObject mockForProtocol:@protocol(IGListAdapterDelegate)];
     [self.announcer addListener:mockDisplayHandler1];
     [[mockDisplayHandler1 expect] listAdapter:self.adapter1 willDisplayObject:object atIndex:0];
-    
+    [[mockDisplayHandler1 expect] listAdapter:self.adapter1 willDisplayObject:object cell: [OCMArg any] atIndexPath:indexPath];
+
     id mockDisplayHandler2 = [OCMockObject mockForProtocol:@protocol(IGListAdapterDelegate)];
     [self.announcer addListener:mockDisplayHandler2];
     [[mockDisplayHandler2 expect] listAdapter:self.adapter1 willDisplayObject:object atIndex:0];
+    [[mockDisplayHandler2 expect] listAdapter:self.adapter1 willDisplayObject:object cell: [OCMArg any] atIndexPath:indexPath];
 
     XCTestExpectation *expectation = genExpectation;
     [self.adapter1 performUpdatesAnimated:NO completion:^(BOOL finished2) {
@@ -103,17 +111,21 @@ - (void)test_whenShowingOneItem_withTwoListeners_withOneAdapter_thatBothListener
 
 - (void)test_whenRemovignOneItem_withTwoListeners_withOneAdapter_thatBothListenersReceivesEndDisplay {
     IGTestObject *const object = genTestObject(@1, @1);
+    NSIndexPath *const zeroIndexPath = [NSIndexPath indexPathForItem:0 inSection:0];
+
     [self setupAdapter1WithObjects:@[object]];
 
     self.dataSource1.objects = @[];
 
     id mockDisplayHandler1 = [OCMockObject mockForProtocol:@protocol(IGListAdapterDelegate)];
     [self.announcer addListener:mockDisplayHandler1];
     [[mockDisplayHandler1 expect] listAdapter:self.adapter1 didEndDisplayingObject:object atIndex:0];
-    
+    [[mockDisplayHandler1 expect] listAdapter:self.adapter1 didEndDisplayingObject:object cell:[OCMArg any] atIndexPath: zeroIndexPath];
+
     id mockDisplayHandler2 = [OCMockObject mockForProtocol:@protocol(IGListAdapterDelegate)];
     [self.announcer addListener:mockDisplayHandler2];
     [[mockDisplayHandler2 expect] listAdapter:self.adapter1 didEndDisplayingObject:object atIndex:0];
+    [[mockDisplayHandler2 expect] listAdapter:self.adapter1 didEndDisplayingObject:object cell:[OCMArg any] atIndexPath: zeroIndexPath];
 
     XCTestExpectation *expectation = genExpectation;
     [self.adapter1 performUpdatesAnimated:NO completion:^(BOOL finished2) {
@@ -130,8 +142,10 @@ - (void)test_whenRemovignOneItem_withTwoListeners_withOneAdapter_thatBothListene
 - (void)test_whenShowingTwoItems_withOneListeners_withTwoAdapters_thatBothItemsSendWillDisplay {
     [self setupAdapter1WithObjects:@[]];
     [self setupAdapter2WithObjects:@[]];
-    
+
     IGTestObject *const object1 = genTestObject(@1, @1);
+    NSIndexPath *const zeroIndexPath = [NSIndexPath indexPathForItem:0 inSection:0];
+
     self.dataSource1.objects = @[
         object1
     ];
@@ -143,9 +157,13 @@ - (void)test_whenShowingTwoItems_withOneListeners_withTwoAdapters_thatBothItemsS
 
     id mockDisplayHandler = [OCMockObject mockForProtocol:@protocol(IGListAdapterDelegate)];
     [self.announcer addListener:mockDisplayHandler];
+
     [[mockDisplayHandler expect] listAdapter:self.adapter1 willDisplayObject:object1 atIndex:0];
+    [[mockDisplayHandler expect] listAdapter:self.adapter1 willDisplayObject:object1 cell: [OCMArg any] atIndexPath: zeroIndexPath];
+
     [[mockDisplayHandler expect] listAdapter:self.adapter2 willDisplayObject:object2 atIndex:0];
-    
+    [[mockDisplayHandler expect] listAdapter:self.adapter2 willDisplayObject:object2 cell: [OCMArg any] atIndexPath: zeroIndexPath];
+
     XCTestExpectation *expectation = genExpectation;
     [self.adapter1 performUpdatesAnimated:NO completion:^(BOOL finished1) {
         [self.adapter2 performUpdatesAnimated:NO completion:^(BOOL finished2) {

Tests/IGListAdapterE2ETests.m

@@ -32,6 +32,7 @@ @implementation IGListAdapterE2ETests
 
 - (void)setUp {
     self.workingRangeSize = 2;
+
     self.dataSource = [IGTestDelegateDataSource new];
     [super setUp];
 }
@@ -820,10 +821,12 @@ - (void)test_whenItemDeleted_withDisplayDelegate_thatDelegateReceivesDeletedItem
         genTestObject(@2, @2),
     ];
 
+    IGTestCell *const cell = (IGTestCell*)[self.collectionView cellForItemAtIndexPath:genIndexPath(0, 0)];
     id mockDisplayHandler = [OCMockObject mockForProtocol:@protocol(IGListAdapterDelegate)];
     self.adapter.delegate = mockDisplayHandler;
 
     [[mockDisplayHandler expect] listAdapter:self.adapter didEndDisplayingObject:object atIndex:0];
+    [[mockDisplayHandler expect] listAdapter:self.adapter didEndDisplayingObject:object cell: cell atIndexPath: [NSIndexPath indexPathForItem:0 inSection:0]];
 
     XCTestExpectation *expectation = genExpectation;
     [self.adapter performUpdatesAnimated:YES completion:^(BOOL finished2) {
@@ -2665,7 +2668,7 @@ - (void)test_whenPerformingUpdates_withAdaptiveDiffing_thatCollectionViewCountsU
     updater.adaptiveDiffingExperimentConfig = (IGListAdaptiveDiffingExperimentConfig) {
         .enabled = YES,
     };
-    
+
     [self setupWithObjects:@[
         genTestObject(@1, @1),
         genTestObject(@2, @2),
@@ -2696,7 +2699,7 @@ - (void)test_whenPerformingUpdates_withAdaptiveCoalescing_thatCollectionViewCoun
     updater.adaptiveCoalescingExperimentConfig = (IGListAdaptiveCoalescingExperimentConfig) {
         .enabled = YES,
     };
-    
+
     [self setupWithObjects:@[
         genTestObject(@1, @1),
         genTestObject(@2, @2),

Tests/IGListDisplayHandlerTests.m

@@ -60,6 +60,7 @@ - (void)test_whenDisplayingFirstCell_thatDisplayHandlerReceivesEvent {
     [[self.mockDisplayDelegate expect] listAdapter:self.adapter willDisplaySectionController:self.list cell:cell atIndex:path.item];
 
     [[self.mockAdapterDelegate expect] listAdapter:self.adapter willDisplayObject:self.object atIndex:path.section];
+    [[self.mockAdapterDelegate expect] listAdapter:self.adapter willDisplayObject:self.object cell:cell atIndexPath:path];
 
     self.list.displayDelegate = self.mockDisplayDelegate;
     self.adapter.delegate = self.mockAdapterDelegate;
@@ -79,6 +80,7 @@ - (void)test_whenDisplayingSecondCell_thatDisplayHandlerReceivesEvent {
     [[self.mockDisplayDelegate expect] listAdapter:self.adapter willDisplaySectionController:self.list cell:cell atIndex:nextPath.item];
     [[self.mockDisplayDelegate reject] listAdapter:self.adapter willDisplaySectionController:self.list];
 
+    [[self.mockAdapterDelegate expect] listAdapter:self.adapter willDisplayObject:self.object cell:cell atIndexPath:nextPath];
     [[self.mockAdapterDelegate reject] listAdapter:self.adapter willDisplayObject:self.object atIndex:firstPath.section];
 
     self.list.displayDelegate = self.mockDisplayDelegate;
@@ -105,6 +107,7 @@ - (void)test_whenEndDisplayingSecondToLastCell_thatDisplayHandlerReceivesEvent {
     [[self.mockDisplayDelegate expect] listAdapter:self.adapter didEndDisplayingSectionController:self.list cell:cellOne atIndex:firstPath.item];
 
     [[self.mockAdapterDelegate reject] listAdapter:self.adapter didEndDisplayingObject:self.object atIndex:firstPath.section];
+    [[self.mockAdapterDelegate expect] listAdapter:self.adapter didEndDisplayingObject:self.object cell:cellOne atIndexPath: firstPath];
 
     self.list.displayDelegate = self.mockDisplayDelegate;
     self.adapter.delegate = self.mockAdapterDelegate;
@@ -125,6 +128,7 @@ - (void)test_whenEndDisplayingLastCell_thatDisplayHandlerReceivesEvent {
     [[self.mockDisplayDelegate expect] listAdapter:self.adapter didEndDisplayingSectionController:self.list cell:cell atIndex:firstPath.item];
 
     [[self.mockAdapterDelegate expect] listAdapter:self.adapter didEndDisplayingObject:self.object atIndex:firstPath.section];
+    [[self.mockAdapterDelegate expect] listAdapter:self.adapter didEndDisplayingObject:self.object cell:cell atIndexPath:firstPath];
 
     self.list.displayDelegate = self.mockDisplayDelegate;
     self.adapter.delegate = self.mockAdapterDelegate;
@@ -158,10 +162,13 @@ - (void)test_whenEndDisplayingCell_withEndDisplayTwice_thatDisplayHandlerReceive
 
     [[self.mockDisplayDelegate expect] listAdapter:self.adapter didEndDisplayingSectionController:self.list];
     [[self.mockDisplayDelegate expect] listAdapter:self.adapter didEndDisplayingSectionController:self.list cell:cell atIndex:firstPath.item];
+
     [[self.mockAdapterDelegate expect] listAdapter:self.adapter didEndDisplayingObject:self.object atIndex:firstPath.section];
+    [[self.mockAdapterDelegate expect] listAdapter:self.adapter didEndDisplayingObject:self.object cell:cell atIndexPath:firstPath];
 
     [[self.mockDisplayDelegate reject] listAdapter:self.adapter didEndDisplayingSectionController:self.list];
     [[self.mockDisplayDelegate reject] listAdapter:self.adapter didEndDisplayingSectionController:self.list cell:cell atIndex:firstPath.item];
+
     [[self.mockAdapterDelegate reject] listAdapter:self.adapter didEndDisplayingObject:self.object atIndex:firstPath.section];
 
     self.list.displayDelegate = self.mockDisplayDelegate;
@@ -216,8 +223,12 @@ - (void)test_whenWillDisplaySupplementaryView_withCellDisplayedAfter_thatDisplay
     [[self.mockDisplayDelegate expect] listAdapter:self.adapter willDisplaySectionController:self.list cell:cell atIndex:path.item];
     [[self.mockAdapterDelegate reject] listAdapter:self.adapter willDisplayObject:self.object atIndex:path.item];
     [[self.mockDisplayDelegate reject] listAdapter:self.adapter willDisplaySectionController:self.list];
+    [[self.mockAdapterDelegate expect] listAdapter:self.adapter willDisplayObject:self.object cell:cell atIndexPath:path];
 
     [self.displayHandler willDisplayCell:cell forListAdapter:self.adapter sectionController:self.list object:self.object indexPath:path];
+
+    [self.mockDisplayDelegate verify];
+    [self.mockAdapterDelegate verify];
 }
 
 - (void)test_whenEndDisplayingSupplementaryView_withEndDisplayingTwice_thatDisplayHandlerReceivesOneEvent {

Tests/Objects/IGTestDelegateController.h

@@ -8,6 +8,7 @@
 #import <Foundation/Foundation.h>
 
 #import <IGListKit/IGListKit.h>
+#import "IGTestCell.h"
 
 @class IGTestObject;
 
@@ -29,4 +30,6 @@
 @property (nonatomic, assign) CGPoint initialAttributesOffset;
 @property (nonatomic, assign) CGPoint finalAttributesOffset;
 
+@property (nonatomic, strong) IGTestCell *overrideCell;
+
 @end

Tests/Objects/IGTestDelegateController.m

@@ -34,7 +34,7 @@ - (CGSize)sizeForItemAtIndex:(NSInteger)index {
 }
 
 - (UICollectionViewCell *)cellForItemAtIndex:(NSInteger)index {
-    IGTestCell *cell = [self.collectionContext dequeueReusableCellOfClass:IGTestCell.class
+    IGTestCell *cell = _overrideCell ?: [self.collectionContext dequeueReusableCellOfClass:IGTestCell.class
                                                           forSectionController:self atIndex:index];
     [[cell label] setText:[NSString stringWithFormat:@"%@", self.item.value]];
     [cell setDelegate:self];

Tests/Objects/IGTestDelegateDataSource.h

@@ -10,6 +10,7 @@
 #import <IGListKit/IGListAdapterDataSource.h>
 
 #import "IGListTestCase.h"
+#import "IGTestCell.h"
 
 @class IGTestDelegateController;
 @class IGTestObject;
@@ -23,4 +24,6 @@ extern NSObject *const kIGTestDelegateDataSourceNoSectionControllerSubclass;
 
 @property (nonatomic, copy) void (^cellConfigureBlock)(IGTestDelegateController *);
 
+@property (nonatomic, strong) IGTestCell *overrideCell;
+
 @end

Tests/Objects/IGTestDelegateDataSource.m

@@ -29,6 +29,7 @@ - (IGListSectionController *)listAdapter:(IGListAdapter *)listAdapter sectionCon
     }
     IGTestDelegateController *sectionController = [[IGTestDelegateController alloc] init];
     sectionController.cellConfigureBlock = self.cellConfigureBlock;
+    sectionController.overrideCell = self.overrideCell;
     return sectionController;
 }