Fix Firestore tests for M22 (#834)

* Add FIRFirestoreTests to the Firestore Xcode project

* Avoid waitForExpectations:timeout:

This API was added in Xcode 8.3, but we still build production releases
with Xcode 8.2. waitForExpectationsWithTimeout:handler: is available
from Xcode 7.2.

* Add AppForUnitTesting

Add a utility for constructing a Firebase App for testing.

* Handle the nil UID from FIRAuth

* Avoid running CMake tests twice

* Only build app_testing on Apple platforms

* Revise test.sh messages

5 files changed, 155 insertions, 43 deletions

diff --git a/Firestore/core/test/firebase/firestore/auth/CMakeLists.txt b/Firestore/core/test/firebase/firestore/auth/CMakeLists.txt
index f470bd7..a6aa2ef 100644
--- a/Firestore/core/test/firebase/firestore/auth/CMakeLists.txt
+++ b/Firestore/core/test/firebase/firestore/auth/CMakeLists.txt
@@ -30,5 +30,6 @@ if(APPLE)
       firebase_credentials_provider_test.mm
     DEPENDS
       firebase_firestore_auth_apple
+      firebase_firestore_testutil
   )
 endif(APPLE)
diff --git a/Firestore/core/test/firebase/firestore/auth/firebase_credentials_provider_test.mm b/Firestore/core/test/firebase/firestore/auth/firebase_credentials_provider_test.mm
index e98d3d8..a6ccc4a 100644
--- a/Firestore/core/test/firebase/firestore/auth/firebase_credentials_provider_test.mm
+++ b/Firestore/core/test/firebase/firestore/auth/firebase_credentials_provider_test.mm
@@ -21,6 +21,7 @@
 #import <FirebaseCore/FIROptionsInternal.h>
 
 #include "Firestore/core/src/firebase/firestore/util/string_apple.h"
+#include "Firestore/core/test/firebase/firestore/testutil/app_testing.h"
 
 #include "gtest/gtest.h"
 
@@ -28,67 +29,51 @@ namespace firebase {
 namespace firestore {
 namespace auth {
 
-// TODO(zxu123): Make this an integration test and get infos from environment.
-// Set a .plist file here to enable the test-case.
-static NSString* const kPlist = @"";
-
-class FirebaseCredentialsProviderTest : public ::testing::Test {
- protected:
-  void SetUp() override {
-    app_ready_ = false;
-    if (![kPlist hasSuffix:@".plist"]) {
-      return;
-    }
-
-    static dispatch_once_t once_token;
-    dispatch_once(&once_token, ^{
-      FIROptions* options = [[FIROptions alloc] initWithContentsOfFile:kPlist];
-      [FIRApp configureWithOptions:options];
-    });
+FIRApp* AppWithFakeUid(NSString* _Nullable uid) {
+  FIRApp* app = testutil::AppForUnitTesting();
+  app.getUIDImplementation = ^NSString* {
+    return uid;
+  };
+  return app;
+}
 
-    // Set getUID implementation.
-    FIRApp* default_app = [FIRApp defaultApp];
-    default_app.getUIDImplementation = ^NSString* {
-      return @"I'm a fake uid.";
-    };
-    app_ready_ = true;
-  }
+TEST(FirebaseCredentialsProviderTest, GetTokenUnauthenticated) {
+  FIRApp* app = AppWithFakeUid(nil);
 
-  bool app_ready_;
-};
+  FirebaseCredentialsProvider credentials_provider(app);
+  credentials_provider.GetToken(
+      /*force_refresh=*/true, [](Token token, const absl::string_view error) {
+        EXPECT_EQ("", token.token());
+        const User& user = token.user();
+        EXPECT_EQ("", user.uid());
+        EXPECT_FALSE(user.is_authenticated());
+        EXPECT_EQ("", error) << error;
+      });
+}
 
-// Set kPlist above before enable.
-TEST_F(FirebaseCredentialsProviderTest, GetToken) {
-  if (!app_ready_) {
-    return;
-  }
+TEST(FirebaseCredentialsProviderTest, GetToken) {
+  FIRApp* app = AppWithFakeUid(@"fake uid");
 
-  FirebaseCredentialsProvider credentials_provider([FIRApp defaultApp]);
+  FirebaseCredentialsProvider credentials_provider(app);
   credentials_provider.GetToken(
       /*force_refresh=*/true, [](Token token, const absl::string_view error) {
         EXPECT_EQ("", token.token());
         const User& user = token.user();
-        EXPECT_EQ("I'm a fake uid.", user.uid());
+        EXPECT_EQ("fake uid", user.uid());
         EXPECT_TRUE(user.is_authenticated());
         EXPECT_EQ("", error) << error;
       });
 }
 
-// Set kPlist above before enable.
-TEST_F(FirebaseCredentialsProviderTest, SetListener) {
-  if (!app_ready_) {
-    return;
-  }
+TEST(FirebaseCredentialsProviderTest, SetListener) {
+  FIRApp* app = AppWithFakeUid(@"fake uid");
 
-  FirebaseCredentialsProvider credentials_provider([FIRApp defaultApp]);
+  FirebaseCredentialsProvider credentials_provider(app);
   credentials_provider.SetUserChangeListener([](User user) {
-    EXPECT_EQ("I'm a fake uid.", user.uid());
+    EXPECT_EQ("fake uid", user.uid());
     EXPECT_TRUE(user.is_authenticated());
   });
 
-  // TODO(wilhuff): We should wait for the above expectations to actually happen
-  // before continuing.
-
   credentials_provider.SetUserChangeListener(nullptr);
 }
 
diff --git a/Firestore/core/test/firebase/firestore/testutil/CMakeLists.txt b/Firestore/core/test/firebase/firestore/testutil/CMakeLists.txt
new file mode 100644
index 0000000..b9fcd47
--- /dev/null
+++ b/Firestore/core/test/firebase/firestore/testutil/CMakeLists.txt
@@ -0,0 +1,35 @@
+# Copyright 2018 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.
+
+cc_library(
+  firebase_firestore_testutil_apple
+  SOURCES
+    app_testing.h
+    app_testing.mm
+  DEPENDS
+    FirebaseCore
+    absl_strings
+)
+
+if(APPLE)
+  list(APPEND TESTUTIL_DEPENDS firebase_firestore_testutil_apple)
+endif()
+
+add_library(
+  firebase_firestore_testutil INTERFACE
+)
+target_link_libraries(
+  firebase_firestore_testutil INTERFACE
+  ${TESTUTIL_DEPENDS}
+)
diff --git a/Firestore/core/test/firebase/firestore/testutil/app_testing.h b/Firestore/core/test/firebase/firestore/testutil/app_testing.h
new file mode 100644
index 0000000..d18ba4f
--- /dev/null
+++ b/Firestore/core/test/firebase/firestore/testutil/app_testing.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2018 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.
+ */
+
+#ifndef FIRESTORE_CORE_TEST_FIREBASE_FIRESTORE_TESTUTIL_APP_TESTING_H_
+#define FIRESTORE_CORE_TEST_FIREBASE_FIRESTORE_TESTUTIL_APP_TESTING_H_
+
+#include "absl/strings/string_view.h"
+
+#if __OBJC__
+
+@class FIRApp;
+
+namespace firebase {
+namespace firestore {
+namespace testutil {
+
+/** Creates a set of default Firebase Options for testing. */
+FIROptions* OptionsForUnitTesting(
+    const absl::string_view project_id = "project_id");
+
+/** Creates a new Firebase App for testing. */
+FIRApp* AppForUnitTesting(const absl::string_view project_id = "project_id");
+
+}  // namespace testutil
+}  // namespace firestore
+}  // namespace firebase
+
+#endif  // __OBJC__
+
+#endif  // FIRESTORE_CORE_TEST_FIREBASE_FIRESTORE_TESTUTIL_APP_TESTING_H_
diff --git a/Firestore/core/test/firebase/firestore/testutil/app_testing.mm b/Firestore/core/test/firebase/firestore/testutil/app_testing.mm
new file mode 100644
index 0000000..21db0db
--- /dev/null
+++ b/Firestore/core/test/firebase/firestore/testutil/app_testing.mm
@@ -0,0 +1,48 @@
+/*
+ * Copyright 2018 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 <FirebaseCore/FIRApp.h>
+#import <FirebaseCore/FIROptions.h>
+
+#include "Firestore/core/src/firebase/firestore/util/string_apple.h"
+#include "Firestore/core/test/firebase/firestore/testutil/app_testing.h"
+
+namespace firebase {
+namespace firestore {
+namespace testutil {
+
+FIROptions* OptionsForUnitTesting(const absl::string_view project_id) {
+  FIROptions* options =
+      [[FIROptions alloc] initWithGoogleAppID:@"1:123:ios:123ab"
+                                  GCMSenderID:@"gcm_sender_id"];
+  options.projectID = util::WrapNSString(project_id);
+  return options;
+}
+
+FIRApp* AppForUnitTesting(const absl::string_view project_id) {
+  static int counter = 0;
+
+  NSString* appName =
+      [NSString stringWithFormat:@"app_for_unit_testing_%d", counter++];
+  FIROptions* options = OptionsForUnitTesting(project_id);
+  [FIRApp configureWithName:appName options:options];
+
+  return [FIRApp appNamed:appName];
+}
+
+}  // namespace testutil
+}  // namespace firestore
+}  // namespace firebase