Making DocumentSnapshot nullable

3 files changed, 31 insertions, 8 deletions

diff --git a/Firestore/Source/Public/FIRDocumentChange.h b/Firestore/Source/Public/FIRDocumentChange.h
index 022c81b..4717067 100644
--- a/Firestore/Source/Public/FIRDocumentChange.h
+++ b/Firestore/Source/Public/FIRDocumentChange.h
@@ -18,7 +18,7 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
-@class FIRDocumentSnapshot;
+@class FIRQueryDocumentSnapshot;
 
 /** An enumeration of document change types. */
 typedef NS_ENUM(NSInteger, FIRDocumentChangeType) {
@@ -47,7 +47,7 @@ NS_SWIFT_NAME(DocumentChange)
 @property(nonatomic, readonly) FIRDocumentChangeType type;
 
 /** The document affected by this change. */
-@property(nonatomic, strong, readonly) FIRDocumentSnapshot *document;
+@property(nonatomic, strong, readonly) FIRQueryDocumentSnapshot *document;
 
 /**
  * The index of the changed document in the result set immediately prior to this FIRDocumentChange
diff --git a/Firestore/Source/Public/FIRDocumentSnapshot.h b/Firestore/Source/Public/FIRDocumentSnapshot.h
index 3e67c25..9706edd 100644
--- a/Firestore/Source/Public/FIRDocumentSnapshot.h
+++ b/Firestore/Source/Public/FIRDocumentSnapshot.h
@@ -46,21 +46,44 @@ NS_SWIFT_NAME(DocumentSnapshot)
 @property(nonatomic, strong, readonly) FIRSnapshotMetadata *metadata;
 
 /**
- * Retrieves all fields in the document as an `NSDictionary`.
+ * Retrieves all fields in the document as an `NSDictionary`. Returns `nil` if the document doesn't
+ * exist.
  *
- * @return An `NSDictionary` containing all fields in the document.
+ * @return An `NSDictionary` containing all fields in the document or `nil` if the document doesn't
+ *      exist.
  */
-- (NSDictionary<NSString *, id> *)data;
+- (nullable NSDictionary<NSString *, id> *)data;
 
 /**
  * Retrieves a specific field from the document.
  *
  * @param key The field to retrieve.
  *
- * @return The value contained in the field or `nil` if the field doesn't exist.
+ * @return The value contained in the field or `nil` if the document or field doesn't exist.
  */
 - (nullable id)objectForKeyedSubscript:(id)key;
 
 @end
 
+/**
+ * A `FIRDocumentSnapshot` contains data read from a document in your Firestore database. The
+ * document is guaranteed to exist and its data can be extracted with the `data` property or by using
+ * subscript syntax to access a specific field.
+ */
+NS_SWIFT_NAME(QueryDocumentSnapshot)
+@interface FIRQueryDocumentSnapshot : FIRDocumentSnapshot
+
+/**   */
+- (instancetype)init
+    __attribute__((unavailable("FIRQueryDocumentSnapshot cannot be created directly.")));
+
+/**
+ * Retrieves all fields in the document as an `NSDictionary`.
+ *
+ * @return An `NSDictionary` containing all fields in the document.
+ */
+- (NSDictionary<NSString *, id> *)data;
+
+@end
+
 NS_ASSUME_NONNULL_END
diff --git a/Firestore/Source/Public/FIRQuerySnapshot.h b/Firestore/Source/Public/FIRQuerySnapshot.h
index c49a07a..1266832 100644
--- a/Firestore/Source/Public/FIRQuerySnapshot.h
+++ b/Firestore/Source/Public/FIRQuerySnapshot.h
@@ -19,8 +19,8 @@
 NS_ASSUME_NONNULL_BEGIN
 
 @class FIRDocumentChange;
-@class FIRDocumentSnapshot;
 @class FIRQuery;
+@class FIRQueryDocumentSnapshot;
 @class FIRSnapshotMetadata;
 
 /**
@@ -50,7 +50,7 @@ NS_SWIFT_NAME(QuerySnapshot)
 @property(nonatomic, readonly) NSInteger count;
 
 /** An Array of the `FIRDocumentSnapshots` that make up this document set. */
-@property(nonatomic, strong, readonly) NSArray<FIRDocumentSnapshot *> *documents;
+@property(nonatomic, strong, readonly) NSArray<FIRQueryDocumentSnapshot *> *documents;
 
 /**
  * An array of the documents that changed since the last snapshot. If this is the first snapshot,