Don't use using statements in Objective-C headers ... (#2827)

use namespace aliases instead.

This makes the Objective-C code much more like what it's going to end up
being like when translated to C++: headers will include classes declared
in a namespace relative to firebase::firestore so everything else will
be named relative to firebase::firestore.

Meanwhile the using statements in the headers were causing us to miss
adding using statements in source files which was moving us away from
where we wanted to be.

Author: wilhuff

Firestore/Example/Tests/API/FIRQuerySnapshotTests.mm

@@ -35,6 +35,10 @@
 #include "Firestore/core/src/firebase/firestore/util/string_apple.h"
 
 namespace util = firebase::firestore::util;
+using firebase::firestore::api::DocumentChange;
+using firebase::firestore::api::DocumentSnapshot;
+using firebase::firestore::api::Firestore;
+using firebase::firestore::api::SnapshotMetadata;
 using firebase::firestore::core::DocumentViewChange;
 using firebase::firestore::core::ViewSnapshot;
 using firebase::firestore::model::DocumentKeySet;

Firestore/Example/Tests/API/FSTAPIHelpers.mm

@@ -40,6 +40,7 @@
 
 namespace testutil = firebase::firestore::testutil;
 namespace util = firebase::firestore::util;
+using firebase::firestore::api::SnapshotMetadata;
 using firebase::firestore::core::DocumentViewChange;
 using firebase::firestore::core::ViewSnapshot;
 using firebase::firestore::model::DocumentKeySet;

Firestore/Example/Tests/Core/FSTEventManagerTests.mm

@@ -37,6 +37,7 @@
 
 using firebase::firestore::core::EventListener;
 using firebase::firestore::core::ListenOptions;
+using firebase::firestore::core::QueryListener;
 using firebase::firestore::core::ViewSnapshot;
 using firebase::firestore::model::DocumentKeySet;
 using firebase::firestore::model::DocumentSet;

Firestore/Example/Tests/Core/FSTQueryListenerTests.mm

@@ -45,6 +45,7 @@
 using firebase::firestore::core::DocumentViewChange;
 using firebase::firestore::core::EventListener;
 using firebase::firestore::core::ListenOptions;
+using firebase::firestore::core::QueryListener;
 using firebase::firestore::core::ViewSnapshot;
 using firebase::firestore::model::DocumentKeySet;
 using firebase::firestore::model::DocumentSet;

Firestore/Example/Tests/Integration/FSTDatastoreTests.mm

@@ -55,6 +55,7 @@
 using firebase::firestore::model::DatabaseId;
 using firebase::firestore::model::DocumentKey;
 using firebase::firestore::model::DocumentKeySet;
+using firebase::firestore::model::FieldValue;
 using firebase::firestore::model::Precondition;
 using firebase::firestore::model::OnlineState;
 using firebase::firestore::model::TargetId;

Firestore/Example/Tests/Model/FSTDocumentTests.mm

@@ -27,6 +27,7 @@
 
 namespace testutil = firebase::firestore::testutil;
 using firebase::firestore::model::DocumentKey;
+using firebase::firestore::model::FieldValue;
 using firebase::firestore::model::SnapshotVersion;
 
 NS_ASSUME_NONNULL_BEGIN

Firestore/Example/Tests/Remote/FSTSerializerBetaTests.mm

@@ -65,6 +65,7 @@
 using firebase::firestore::model::DatabaseId;
 using firebase::firestore::model::FieldMask;
 using firebase::firestore::model::FieldTransform;
+using firebase::firestore::model::FieldValue;
 using firebase::firestore::model::Precondition;
 using firebase::firestore::model::SnapshotVersion;
 using firebase::firestore::remote::DocumentWatchChange;

Firestore/Example/Tests/SpecTests/FSTSyncEngineTestDriver.mm

@@ -61,6 +61,7 @@
 using firebase::firestore::auth::User;
 using firebase::firestore::core::DatabaseInfo;
 using firebase::firestore::core::ListenOptions;
+using firebase::firestore::core::QueryListener;
 using firebase::firestore::core::ViewSnapshot;
 using firebase::firestore::model::DatabaseId;
 using firebase::firestore::model::DocumentKey;

Firestore/Source/API/FIRCollectionReference+Internal.h

@@ -18,11 +18,13 @@
 
 #include "Firestore/core/src/firebase/firestore/model/resource_path.h"
 
+namespace model = firebase::firestore::model;
+
 NS_ASSUME_NONNULL_BEGIN
 
 /** Internal FIRCollectionReference API we don't want exposed in our public header files. */
 @interface FIRCollectionReference (Internal)
-+ (instancetype)referenceWithPath:(const firebase::firestore::model::ResourcePath &)path
++ (instancetype)referenceWithPath:(const model::ResourcePath &)path
                         firestore:(FIRFirestore *)firestore;
 @end
 

Firestore/Source/API/FIRDocumentChange+Internal.h

@@ -20,13 +20,14 @@
 
 #include "Firestore/core/src/firebase/firestore/api/document_change.h"
 
-using firebase::firestore::api::DocumentChange;
+namespace api = firebase::firestore::api;
 
 NS_ASSUME_NONNULL_BEGIN
 
 @interface FIRDocumentChange (/* Init */)
 
-- (instancetype)initWithDocumentChange:(DocumentChange &&)documentChange NS_DESIGNATED_INITIALIZER;
+- (instancetype)initWithDocumentChange:(api::DocumentChange &&)documentChange
+    NS_DESIGNATED_INITIALIZER;
 
 @end
 

Firestore/Source/API/FIRDocumentReference+Internal.h

@@ -20,25 +20,25 @@
 #include "Firestore/core/src/firebase/firestore/model/document_key.h"
 #include "Firestore/core/src/firebase/firestore/model/resource_path.h"
 
+namespace api = firebase::firestore::api;
+namespace model = firebase::firestore::model;
+
 NS_ASSUME_NONNULL_BEGIN
 
 @interface FIRDocumentReference (/* Init */)
 
-- (instancetype)initWithReference:(firebase::firestore::api::DocumentReference &&)reference
-    NS_DESIGNATED_INITIALIZER;
+- (instancetype)initWithReference:(api::DocumentReference &&)reference NS_DESIGNATED_INITIALIZER;
 
-- (instancetype)initWithPath:(firebase::firestore::model::ResourcePath)path
-                   firestore:(firebase::firestore::api::Firestore *)firestore;
+- (instancetype)initWithPath:(model::ResourcePath)path firestore:(api::Firestore *)firestore;
 
-- (instancetype)initWithKey:(firebase::firestore::model::DocumentKey)key
-                  firestore:(firebase::firestore::api::Firestore *)firestore;
+- (instancetype)initWithKey:(model::DocumentKey)key firestore:(api::Firestore *)firestore;
 
 @end
 
 /** Internal FIRDocumentReference API we don't want exposed in our public header files. */
 @interface FIRDocumentReference (Internal)
 
-- (const firebase::firestore::model::DocumentKey &)key;
+- (const model::DocumentKey &)key;
 
 @end
 

Firestore/Source/API/FIRDocumentReference.mm

@@ -50,6 +50,7 @@
 using firebase::firestore::api::DocumentReference;
 using firebase::firestore::api::DocumentSnapshot;
 using firebase::firestore::api::Firestore;
+using firebase::firestore::api::ListenerRegistration;
 using firebase::firestore::api::Source;
 using firebase::firestore::api::MakeSource;
 using firebase::firestore::api::ThrowInvalidArgument;

Firestore/Source/API/FIRDocumentSnapshot+Internal.h

@@ -23,24 +23,22 @@
 @class FIRFirestore;
 @class FSTDocument;
 
-using firebase::firestore::api::DocumentSnapshot;
-using firebase::firestore::api::Firestore;
-using firebase::firestore::api::SnapshotMetadata;
-using firebase::firestore::model::DocumentKey;
+namespace api = firebase::firestore::api;
+namespace model = firebase::firestore::model;
 
 NS_ASSUME_NONNULL_BEGIN
 
 @interface FIRDocumentSnapshot (/* Init */)
 
-- (instancetype)initWithSnapshot:(DocumentSnapshot &&)snapshot NS_DESIGNATED_INITIALIZER;
+- (instancetype)initWithSnapshot:(api::DocumentSnapshot &&)snapshot NS_DESIGNATED_INITIALIZER;
 
-- (instancetype)initWithFirestore:(Firestore *)firestore
-                      documentKey:(DocumentKey)documentKey
+- (instancetype)initWithFirestore:(api::Firestore *)firestore
+                      documentKey:(model::DocumentKey)documentKey
                          document:(nullable FSTDocument *)document
-                         metadata:(SnapshotMetadata)metadata;
+                         metadata:(api::SnapshotMetadata)metadata;
 
-- (instancetype)initWithFirestore:(Firestore *)firestore
-                      documentKey:(DocumentKey)documentKey
+- (instancetype)initWithFirestore:(api::Firestore *)firestore
+                      documentKey:(model::DocumentKey)documentKey
                          document:(nullable FSTDocument *)document
                         fromCache:(bool)fromCache
                  hasPendingWrites:(bool)hasPendingWrites;

Firestore/Source/API/FIRDocumentSnapshot.mm

@@ -41,6 +41,7 @@
 namespace util = firebase::firestore::util;
 using firebase::firestore::api::DocumentSnapshot;
 using firebase::firestore::api::Firestore;
+using firebase::firestore::api::SnapshotMetadata;
 using firebase::firestore::api::ThrowInvalidArgument;
 using firebase::firestore::model::DatabaseId;
 using firebase::firestore::model::DocumentKey;

Firestore/Source/API/FIRFieldPath+Internal.h

@@ -18,14 +18,16 @@
 
 #include "Firestore/core/src/firebase/firestore/model/field_path.h"
 
+namespace model = firebase::firestore::model;
+
 NS_ASSUME_NONNULL_BEGIN
 
 @interface FIRFieldPath ()
 
 /** Internal field path representation */
-- (const firebase::firestore::model::FieldPath &)internalValue;
+- (const model::FieldPath &)internalValue;
 
-- (instancetype)initPrivate:(firebase::firestore::model::FieldPath)path NS_DESIGNATED_INITIALIZER;
+- (instancetype)initPrivate:(model::FieldPath)path NS_DESIGNATED_INITIALIZER;
 
 @end
 

Firestore/Source/API/FIRFirestore+Internal.h

@@ -23,26 +23,29 @@
 #include "Firestore/core/src/firebase/firestore/auth/credentials_provider.h"
 #include "Firestore/core/src/firebase/firestore/util/async_queue.h"
 
-NS_ASSUME_NONNULL_BEGIN
-
 @class FIRApp;
 @class FSTFirestoreClient;
 @class FSTUserDataConverter;
 
+namespace api = firebase::firestore::api;
+namespace auth = firebase::firestore::auth;
+namespace model = firebase::firestore::model;
+namespace util = firebase::firestore::util;
+
+NS_ASSUME_NONNULL_BEGIN
+
 @interface FIRFirestore (/* Init */)
 
 /**
  * Initializes a Firestore object with all the required parameters directly. This exists so that
  * tests can create FIRFirestore objects without needing FIRApp.
  */
-- (instancetype)
-      initWithProjectID:(std::string)projectID
-               database:(std::string)database
-         persistenceKey:(std::string)persistenceKey
-    credentialsProvider:
-        (std::unique_ptr<firebase::firestore::auth::CredentialsProvider>)credentialsProvider
-            workerQueue:(std::unique_ptr<firebase::firestore::util::AsyncQueue>)workerQueue
-            firebaseApp:(FIRApp *)app;
+- (instancetype)initWithProjectID:(std::string)projectID
+                         database:(std::string)database
+                   persistenceKey:(std::string)persistenceKey
+              credentialsProvider:(std::unique_ptr<auth::CredentialsProvider>)credentialsProvider
+                      workerQueue:(std::unique_ptr<util::AsyncQueue>)workerQueue
+                      firebaseApp:(FIRApp *)app;
 @end
 
 /** Internal FIRFirestore API we don't want exposed in our public header files. */
@@ -51,7 +54,7 @@ NS_ASSUME_NONNULL_BEGIN
 /** Checks to see if logging is is globally enabled for the Firestore client. */
 + (BOOL)isLoggingEnabled;
 
-+ (FIRFirestore *)recoverFromFirestore:(firebase::firestore::api::Firestore *)firestore;
++ (FIRFirestore *)recoverFromFirestore:(api::Firestore *)firestore;
 
 /**
  * Shutdown this `FIRFirestore`, releasing all resources (abandoning any outstanding writes,
@@ -62,12 +65,12 @@ NS_ASSUME_NONNULL_BEGIN
 - (void)shutdownWithCompletion:(nullable void (^)(NSError *_Nullable error))completion
     NS_SWIFT_NAME(shutdown(completion:));
 
-@property(nonatomic, assign, readonly) firebase::firestore::api::Firestore *wrapped;
+@property(nonatomic, assign, readonly) api::Firestore *wrapped;
 
-@property(nonatomic, assign, readonly) firebase::firestore::util::AsyncQueue *workerQueue;
+@property(nonatomic, assign, readonly) util::AsyncQueue *workerQueue;
 
 // FIRFirestore ownes the DatabaseId instance.
-@property(nonatomic, assign, readonly) const firebase::firestore::model::DatabaseId *databaseID;
+@property(nonatomic, assign, readonly) const model::DatabaseId *databaseID;
 @property(nonatomic, strong, readonly) FSTUserDataConverter *dataConverter;
 
 @end

Firestore/Source/API/FIRListenerRegistration+Internal.h

@@ -18,14 +18,14 @@
 
 #include "Firestore/core/src/firebase/firestore/api/listener_registration.h"
 
-NS_ASSUME_NONNULL_BEGIN
+namespace api = firebase::firestore::api;
 
-using firebase::firestore::api::ListenerRegistration;
+NS_ASSUME_NONNULL_BEGIN
 
 /** Private implementation of the FIRListenerRegistration protocol. */
 @interface FSTListenerRegistration : NSObject <FIRListenerRegistration>
 
-- (instancetype)initWithRegistration:(ListenerRegistration &&)registration;
+- (instancetype)initWithRegistration:(api::ListenerRegistration &&)registration;
 
 @end
 

Firestore/Source/API/FIRListenerRegistration.mm

@@ -25,10 +25,10 @@
 using firebase::firestore::util::DelayedConstructor;
 
 @implementation FSTListenerRegistration {
-  DelayedConstructor<ListenerRegistration> _registration;
+  DelayedConstructor<api::ListenerRegistration> _registration;
 }
 
-- (instancetype)initWithRegistration:(ListenerRegistration &&)registration {
+- (instancetype)initWithRegistration:(api::ListenerRegistration &&)registration {
   if (self = [super init]) {
     _registration.Init(std::move(registration));
   }

Firestore/Source/API/FIRQuery.mm

@@ -51,12 +51,16 @@
 #include "Firestore/core/src/firebase/firestore/util/string_apple.h"
 
 namespace util = firebase::firestore::util;
-using firebase::firestore::api::MakeSource;
+using firebase::firestore::api::Firestore;
+using firebase::firestore::api::ListenerRegistration;
+using firebase::firestore::api::SnapshotMetadata;
 using firebase::firestore::api::Source;
 using firebase::firestore::api::ThrowInvalidArgument;
 using firebase::firestore::core::AsyncEventListener;
 using firebase::firestore::core::EventListener;
 using firebase::firestore::core::Filter;
+using firebase::firestore::core::ListenOptions;
+using firebase::firestore::core::QueryListener;
 using firebase::firestore::core::ViewSnapshot;
 using firebase::firestore::model::DocumentKey;
 using firebase::firestore::model::FieldPath;
@@ -121,7 +125,7 @@ - (void)getDocumentsWithCompletion:(void (^)(FIRQuerySnapshot *_Nullable snapsho
 - (void)getDocumentsWithSource:(FIRFirestoreSource)publicSource
                     completion:(void (^)(FIRQuerySnapshot *_Nullable snapshot,
                                          NSError *_Nullable error))completion {
-  Source source = MakeSource(publicSource);
+  Source source = api::MakeSource(publicSource);
   if (source == Source::Cache) {
     [self.firestore.wrapped->client() getDocumentsFromLocalCache:self completion:completion];
     return;

Firestore/Source/API/FIRQuerySnapshot+Internal.h

@@ -25,22 +25,20 @@
 @class FIRSnapshotMetadata;
 @class FSTQuery;
 
-using firebase::firestore::api::Firestore;
-using firebase::firestore::api::QuerySnapshot;
-using firebase::firestore::api::SnapshotMetadata;
-using firebase::firestore::core::ViewSnapshot;
+namespace api = firebase::firestore::api;
+namespace core = firebase::firestore::core;
 
 NS_ASSUME_NONNULL_BEGIN
 
 /** Internal FIRQuerySnapshot API we don't want exposed in our public header files. */
 @interface FIRQuerySnapshot (/* Init */)
 
-- (instancetype)initWithSnapshot:(QuerySnapshot &&)snapshot NS_DESIGNATED_INITIALIZER;
+- (instancetype)initWithSnapshot:(api::QuerySnapshot &&)snapshot NS_DESIGNATED_INITIALIZER;
 
-- (instancetype)initWithFirestore:(Firestore *)firestore
+- (instancetype)initWithFirestore:(api::Firestore *)firestore
                     originalQuery:(FSTQuery *)query
-                         snapshot:(ViewSnapshot &&)snapshot
-                         metadata:(SnapshotMetadata)metadata;
+                         snapshot:(core::ViewSnapshot &&)snapshot
+                         metadata:(api::SnapshotMetadata)metadata;
 
 @end
 

Firestore/Source/API/FIRQuerySnapshot.mm

@@ -32,8 +32,11 @@
 #include "Firestore/core/src/firebase/firestore/model/document_set.h"
 #include "Firestore/core/src/firebase/firestore/util/delayed_constructor.h"
 
+using firebase::firestore::api::DocumentChange;
+using firebase::firestore::api::DocumentSnapshot;
 using firebase::firestore::api::Firestore;
 using firebase::firestore::api::QuerySnapshot;
+using firebase::firestore::api::SnapshotMetadata;
 using firebase::firestore::api::ThrowInvalidArgument;
 using firebase::firestore::core::ViewSnapshot;
 using firebase::firestore::util::DelayedConstructor;

Firestore/Source/API/FIRSnapshotMetadata+Internal.h

@@ -20,13 +20,13 @@
 
 #include "Firestore/core/src/firebase/firestore/api/snapshot_metadata.h"
 
-using firebase::firestore::api::SnapshotMetadata;
+namespace api = firebase::firestore::api;
 
 NS_ASSUME_NONNULL_BEGIN
 
 @interface FIRSnapshotMetadata (/* Init */)
 
-- (instancetype)initWithMetadata:(SnapshotMetadata)metadata NS_DESIGNATED_INITIALIZER;
+- (instancetype)initWithMetadata:(api::SnapshotMetadata)metadata NS_DESIGNATED_INITIALIZER;
 
 - (instancetype)initWithPendingWrites:(bool)pendingWrites fromCache:(bool)fromCache;