implement C++ logger (#575)

* implement logger, apple impl and other impl, with test.

* some minor fixes

*   re-organize cmake build rules;
*   fix bugs in log_apple.mm;

* style fix by style.sh

* Complete removal of LogAssert

2 files changed, 52 insertions, 0 deletions

diff --git a/Firestore/core/test/firebase/firestore/util/CMakeLists.txt b/Firestore/core/test/firebase/firestore/util/CMakeLists.txt
index 223fa41..ae2c3b0 100644
--- a/Firestore/core/test/firebase/firestore/util/CMakeLists.txt
+++ b/Firestore/core/test/firebase/firestore/util/CMakeLists.txt
@@ -15,6 +15,7 @@
 cc_test(
   firebase_firestore_util_test
   autoid_test.cc
+  log_test.cc
   secure_random_test.cc
 )
 target_link_libraries(
diff --git a/Firestore/core/test/firebase/firestore/util/log_test.cc b/Firestore/core/test/firebase/firestore/util/log_test.cc
new file mode 100644
index 0000000..09b2c08
--- /dev/null
+++ b/Firestore/core/test/firebase/firestore/util/log_test.cc
@@ -0,0 +1,51 @@
+/*
+ * 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.
+ */
+
+#include "Firestore/core/src/firebase/firestore/util/log.h"
+
+#include "gtest/gtest.h"
+
+namespace firebase {
+namespace firestore {
+namespace util {
+
+TEST(Log, SetAndGet) {
+  LogSetLevel(kLogLevelVerbose);
+
+  LogSetLevel(kLogLevelDebug);
+  EXPECT_EQ(kLogLevelDebug, LogGetLevel());
+
+  LogSetLevel(kLogLevelInfo);
+  EXPECT_EQ(kLogLevelInfo, LogGetLevel());
+
+  LogSetLevel(kLogLevelWarning);
+  EXPECT_EQ(kLogLevelWarning, LogGetLevel());
+
+  LogSetLevel(kLogLevelError);
+  EXPECT_EQ(kLogLevelError, LogGetLevel());
+}
+
+TEST(Log, LogAllKinds) {
+  LogDebug("test debug logging %d", 1);
+  LogInfo("test info logging %d", 2);
+  LogWarning("test warning logging %d", 3);
+  LogError("test error logging %d", 4);
+  LogMessage(kLogLevelError, "test va-args %s %c %d", "abc", ':', 123);
+}
+
+}  //  namespace util
+}  //  namespace firestore
+}  //  namespace firebase