1 files changed, 39 insertions, 0 deletions
diff --git a/Firestore/Port/string_util_test.cc b/Firestore/Port/string_util_test.cc
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+++ b/Firestore/Port/string_util_test.cc
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+/*
+ * 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 "string_util.h"
+
+#include "testing/base/public/gunit.h"
+#include <leveldb/db.h>
+
+using Firestore::PrefixSuccessor;
+using Firestore::ImmediateSuccessor;
+using leveldb::Slice;
+
+TEST(Util, PrefixSuccessor) {
+  EXPECT_EQ(PrefixSuccessor("a"), "b");
+  EXPECT_EQ(PrefixSuccessor("aaAA"), "aaAB");
+  EXPECT_EQ(PrefixSuccessor("aaa\xff"), "aab");
+  EXPECT_EQ(PrefixSuccessor(string("\x00", 1)), "\x01");
+  EXPECT_EQ(PrefixSuccessor("az\xe0"), "az\xe1");
+  EXPECT_EQ(PrefixSuccessor("\xff\xff\xff"), "");
+  EXPECT_EQ(PrefixSuccessor(""), "");
+}
+
+TEST(Util, ImmediateSuccessor) {
+  EXPECT_EQ(ImmediateSuccessor("hello"), Slice("hello\0", 6));
+  EXPECT_EQ(ImmediateSuccessor(""), Slice("\0", 1));
+}