Implement Firestore DatabaseInfo and port both Database{Id,Info} C++ to the iOS code (#738)

* implement Firestore DatabaseInfo in C++

* temporary stash changes; blocking on the massive renaming of .m to .mm

* add database_info_test to project

* finish port DatabaseId and fix style, modular fixing DatabaseInfo

* port DatabaseInfo

* remove FSTDatabase{ID,Info} and their tests from project

* fix unit test

* use namespace alias

* use namespace alias, leftover

* address more changes

* refactoring to use raw pointer instead of value for property

* address changes

* remove self->

* fix style

* remove the name suffix Alloc

* fix a bug

2 files changed, 27 insertions, 13 deletions

diff --git a/Firestore/Example/Tests/Util/FSTHelpers.mm b/Firestore/Example/Tests/Util/FSTHelpers.mm
index 64fe213..406d4dd 100644
--- a/Firestore/Example/Tests/Util/FSTHelpers.mm
+++ b/Firestore/Example/Tests/Util/FSTHelpers.mm
@@ -17,6 +17,7 @@
 #import "Firestore/Example/Tests/Util/FSTHelpers.h"
 
 #include <inttypes.h>
+#include <vector>
 
 #import <FirebaseFirestore/FIRFieldPath.h>
 #import <FirebaseFirestore/FIRGeoPoint.h>
@@ -30,7 +31,6 @@
 #import "Firestore/Source/Core/FSTViewSnapshot.h"
 #import "Firestore/Source/Local/FSTLocalViewChanges.h"
 #import "Firestore/Source/Local/FSTQueryData.h"
-#import "Firestore/Source/Model/FSTDatabaseID.h"
 #import "Firestore/Source/Model/FSTDocument.h"
 #import "Firestore/Source/Model/FSTDocumentKey.h"
 #import "Firestore/Source/Model/FSTDocumentSet.h"
@@ -41,6 +41,12 @@
 #import "Firestore/Source/Remote/FSTWatchChange.h"
 #import "Firestore/Source/Util/FSTAssert.h"
 
+#include "Firestore/core/src/firebase/firestore/model/database_id.h"
+#include "Firestore/core/src/firebase/firestore/util/string_apple.h"
+
+namespace util = firebase::firestore::util;
+using firebase::firestore::model::DatabaseId;
+
 NS_ASSUME_NONNULL_BEGIN
 
 /** A string sentinel that can be used with FSTTestPatchMutation() to mark a field for deletion. */
@@ -100,10 +106,10 @@ FSTFieldPath *FSTTestFieldPath(NSString *field) {
 }
 
 FSTFieldValue *FSTTestFieldValue(id _Nullable value) {
-  FSTDatabaseID *databaseID =
-      [FSTDatabaseID databaseIDWithProject:@"project" database:kDefaultDatabaseID];
+  // This owns the DatabaseIds since we do not have FirestoreClient instance to own them.
+  static DatabaseId database_id{"project", DatabaseId::kDefaultDatabaseId};
   FSTUserDataConverter *converter =
-      [[FSTUserDataConverter alloc] initWithDatabaseID:databaseID
+      [[FSTUserDataConverter alloc] initWithDatabaseID:&database_id
                                           preConverter:^id _Nullable(id _Nullable input) {
                                             return input;
                                           }];
@@ -167,8 +173,11 @@ FSTResourcePath *FSTTestPath(NSString *path) {
 }
 
 FSTDocumentKeyReference *FSTTestRef(NSString *projectID, NSString *database, NSString *path) {
-  FSTDatabaseID *databaseID = [FSTDatabaseID databaseIDWithProject:projectID database:database];
-  return [[FSTDocumentKeyReference alloc] initWithKey:FSTTestDocKey(path) databaseID:databaseID];
+  // This owns the DatabaseIds since we do not have FirestoreClient instance to own them.
+  static std::vector<DatabaseId> database_ids;
+  database_ids.emplace_back(util::MakeStringView(projectID), util::MakeStringView(database));
+  return [[FSTDocumentKeyReference alloc] initWithKey:FSTTestDocKey(path)
+                                           databaseID:&database_ids.back()];
 }
 
 FSTQuery *FSTTestQuery(NSString *path) {
diff --git a/Firestore/Example/Tests/Util/FSTIntegrationTestCase.mm b/Firestore/Example/Tests/Util/FSTIntegrationTestCase.mm
index ef15056..df591b0 100644
--- a/Firestore/Example/Tests/Util/FSTIntegrationTestCase.mm
+++ b/Firestore/Example/Tests/Util/FSTIntegrationTestCase.mm
@@ -27,12 +27,16 @@
 #import "Firestore/Source/Auth/FSTEmptyCredentialsProvider.h"
 #import "Firestore/Source/Core/FSTFirestoreClient.h"
 #import "Firestore/Source/Local/FSTLevelDB.h"
-#import "Firestore/Source/Model/FSTDatabaseID.h"
 #import "Firestore/Source/Util/FSTDispatchQueue.h"
 
 #import "Firestore/Example/Tests/Util/FSTEventAccumulator.h"
 #import "Firestore/Example/Tests/Util/FSTTestDispatchQueue.h"
 
+#include "Firestore/core/src/firebase/firestore/model/database_id.h"
+#include "Firestore/core/src/firebase/firestore/util/string_apple.h"
+
+namespace util = firebase::firestore::util;
+using firebase::firestore::model::DatabaseId;
 using firebase::firestore::util::CreateAutoId;
 
 NS_ASSUME_NONNULL_BEGIN
@@ -137,12 +141,13 @@ NS_ASSUME_NONNULL_BEGIN
   FIRSetLoggerLevel(FIRLoggerLevelDebug);
   // HACK: FIRFirestore expects a non-nil app, but for tests we cheat.
   FIRApp *app = nil;
-  FIRFirestore *firestore = [[FIRFirestore alloc] initWithProjectID:projectID
-                                                           database:kDefaultDatabaseID
-                                                     persistenceKey:persistenceKey
-                                                credentialsProvider:credentialsProvider
-                                                workerDispatchQueue:workerDispatchQueue
-                                                        firebaseApp:app];
+  FIRFirestore *firestore = [[FIRFirestore alloc]
+        initWithProjectID:projectID
+                 database:util::WrapNSStringNoCopy(DatabaseId::kDefaultDatabaseId)
+           persistenceKey:persistenceKey
+      credentialsProvider:credentialsProvider
+      workerDispatchQueue:workerDispatchQueue
+              firebaseApp:app];
 
   firestore.settings = [FSTIntegrationTestCase settings];