1 files changed, 95 insertions, 0 deletions
diff --git a/Firestore/Source/Model/FSTDocumentSet.h b/Firestore/Source/Model/FSTDocumentSet.h
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+++ b/Firestore/Source/Model/FSTDocumentSet.h
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+/*
+ * Copyright 2017 Google
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#import <Foundation/Foundation.h>
+
+#import "FSTDocumentDictionary.h"
+
+@class FSTDocument;
+@class FSTDocumentKey;
+
+NS_ASSUME_NONNULL_BEGIN
+
+/**
+ * DocumentSet is an immutable (copy-on-write) collection that holds documents in order specified
+ * by the provided comparator. We always add a document key comparator on top of what is provided
+ * to guarantee document equality based on the key.
+ */
+@interface FSTDocumentSet : NSObject
+
+/** Creates a new, empty FSTDocumentSet sorted by the given comparator, then by keys. */
++ (instancetype)documentSetWithComparator:(NSComparator)comparator;
+
+- (instancetype)init __attribute__((unavailable("Use a static constructor instead")));
+
+- (NSUInteger)count;
+
+/** Returns true if the dictionary contains no elements. */
+- (BOOL)isEmpty;
+
+/** Returns YES if this set contains a document with the given key. */
+- (BOOL)containsKey:(FSTDocumentKey *)key;
+
+/** Returns the document from this set with the given key if it exists or nil if it doesn't. */
+- (FSTDocument *_Nullable)documentForKey:(FSTDocumentKey *)key;
+
+/**
+ * Returns the first document in the set according to its built in ordering, or nil if the set
+ * is empty.
+ */
+- (FSTDocument *_Nullable)firstDocument;
+
+/**
+ * Returns the last document in the set according to its built in ordering, or nil if the set
+ * is empty.
+ */
+- (FSTDocument *_Nullable)lastDocument;
+
+/**
+ * Returns the document previous to the document associated with the given key in the set according
+ * to its built in ordering. Returns nil if the document associated with the given key is the
+ * first document.
+ *
+ * @param key A key that must be present in the DocumentSet.
+ * @throws NSInvalidArgumentException if key is not present.
+ */
+- (FSTDocument *_Nullable)predecessorDocumentForKey:(FSTDocumentKey *)key;
+
+/**
+ * Returns the index of the document with the provided key in the document set. Returns NSNotFound
+ * if the key is not present.
+ */
+- (NSUInteger)indexOfKey:(FSTDocumentKey *)key;
+
+- (NSEnumerator<FSTDocument *> *)documentEnumerator;
+
+/** Returns a copy of the documents in this set as an array. This is O(n) on the size of the set. */
+- (NSArray<FSTDocument *> *)arrayValue;
+
+/**
+ * Returns the documents as a FSTMaybeDocumentDictionary. This is O(1) as this leverages our
+ * internal representation.
+ */
+- (FSTMaybeDocumentDictionary *)dictionaryValue;
+
+/** Returns a new FSTDocumentSet that contains the given document. */
+- (instancetype)documentSetByAddingDocument:(FSTDocument *_Nullable)document;
+
+/** Returns a new FSTDocumentSet that excludes any document associated with the given key. */
+- (instancetype)documentSetByRemovingKey:(FSTDocumentKey *)key;
+@end
+
+NS_ASSUME_NONNULL_END