Avoid wrapping and rewrapping NSStrings when constructing DatabaseId (#833)

* Avoid wrapping and rewrapping NSStrings when constructing DatabaseId

* Shorten DatabaseId::kDefaultDatabaseId

2 files changed, 11 insertions, 12 deletions

diff --git a/Firestore/Source/API/FIRFirestore+Internal.h b/Firestore/Source/API/FIRFirestore+Internal.h
index 717a08b..7bc419a 100644
--- a/Firestore/Source/API/FIRFirestore+Internal.h
+++ b/Firestore/Source/API/FIRFirestore+Internal.h
@@ -17,6 +17,7 @@
 #import "FIRFirestore.h"
 
 #include "Firestore/core/src/firebase/firestore/model/database_id.h"
+#include "absl/strings/string_view.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -31,8 +32,8 @@ NS_ASSUME_NONNULL_BEGIN
  * Initializes a Firestore object with all the required parameters directly. This exists so that
  * tests can create FIRFirestore objects without needing FIRApp.
  */
-- (instancetype)initWithProjectID:(NSString *)projectID
-                         database:(NSString *)database
+- (instancetype)initWithProjectID:(const absl::string_view)projectID
+                         database:(const absl::string_view)database
                    persistenceKey:(NSString *)persistenceKey
               credentialsProvider:(id<FSTCredentialsProvider>)credentialsProvider
               workerDispatchQueue:(FSTDispatchQueue *)workerDispatchQueue
diff --git a/Firestore/Source/API/FIRFirestore.mm b/Firestore/Source/API/FIRFirestore.mm
index 5a50710..ce8f8ab 100644
--- a/Firestore/Source/API/FIRFirestore.mm
+++ b/Firestore/Source/API/FIRFirestore.mm
@@ -117,13 +117,11 @@ extern "C" NSString *const FIRFirestoreErrorDomain = @"FIRFirestoreErrorDomain";
                          @"Failed to get FirebaseApp instance. Please call FirebaseApp.configure() "
                          @"before using Firestore");
   }
-  return
-      [self firestoreForApp:app database:util::WrapNSStringNoCopy(DatabaseId::kDefaultDatabaseId)];
+  return [self firestoreForApp:app database:util::WrapNSStringNoCopy(DatabaseId::kDefault)];
 }
 
 + (instancetype)firestoreForApp:(FIRApp *)app {
-  return
-      [self firestoreForApp:app database:util::WrapNSStringNoCopy(DatabaseId::kDefaultDatabaseId)];
+  return [self firestoreForApp:app database:util::WrapNSStringNoCopy(DatabaseId::kDefault)];
 }
 
 // TODO(b/62410906): make this public
@@ -137,7 +135,7 @@ extern "C" NSString *const FIRFirestoreErrorDomain = @"FIRFirestoreErrorDomain";
     FSTThrowInvalidArgument(
         @"database identifier may not be nil. Use '%@' if you want the default "
          "database",
-        util::WrapNSStringNoCopy(DatabaseId::kDefaultDatabaseId));
+        util::WrapNSStringNoCopy(DatabaseId::kDefault));
   }
 
   // Note: If the key format changes, please change the code that detects FIRApps being deleted
@@ -159,8 +157,8 @@ extern "C" NSString *const FIRFirestoreErrorDomain = @"FIRFirestoreErrorDomain";
 
       NSString *persistenceKey = app.name;
 
-      firestore = [[FIRFirestore alloc] initWithProjectID:projectID
-                                                 database:database
+      firestore = [[FIRFirestore alloc] initWithProjectID:util::MakeStringView(projectID)
+                                                 database:util::MakeStringView(database)
                                            persistenceKey:persistenceKey
                                       credentialsProvider:credentialsProvider
                                       workerDispatchQueue:workerDispatchQueue
@@ -172,14 +170,14 @@ extern "C" NSString *const FIRFirestoreErrorDomain = @"FIRFirestoreErrorDomain";
   }
 }
 
-- (instancetype)initWithProjectID:(NSString *)projectID
-                         database:(NSString *)database
+- (instancetype)initWithProjectID:(const absl::string_view)projectID
+                         database:(const absl::string_view)database
                    persistenceKey:(NSString *)persistenceKey
               credentialsProvider:(id<FSTCredentialsProvider>)credentialsProvider
               workerDispatchQueue:(FSTDispatchQueue *)workerDispatchQueue
                       firebaseApp:(FIRApp *)app {
   if (self = [super init]) {
-    _databaseID = DatabaseId(util::MakeStringView(projectID), util::MakeStringView(database));
+    _databaseID = DatabaseId(projectID, database);
     FSTPreConverterBlock block = ^id _Nullable(id _Nullable input) {
       if ([input isKindOfClass:[FIRDocumentReference class]]) {
         FIRDocumentReference *documentReference = (FIRDocumentReference *)input;