Reduce memory use of GetLevenshteinDistance() by almost 50%

components/ssl_errors/error_classification_unittest.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/ssl_errors/error_classification.h"
 
 #include "base/files/file_path.h"
 #include "base/strings/string_split.h"
 #include "net/base/net_errors.h"
 #include "net/base/test_data_directory.h"
@@ skipping 135 matching lines @@
   EXPECT_TRUE(ssl_errors::IsHostNameKnownTLD("b.appspot.com"));
   EXPECT_FALSE(ssl_errors::IsHostNameKnownTLD("a.private"));
 }
 
 TEST_F(SSLErrorClassificationTest, TestPrivateURL) {
   EXPECT_FALSE(ssl_errors::IsHostnameNonUniqueOrDotless("www.foogoogle.com."));
   EXPECT_TRUE(ssl_errors::IsHostnameNonUniqueOrDotless("go"));
   EXPECT_TRUE(ssl_errors::IsHostnameNonUniqueOrDotless("172.17.108.108"));
   EXPECT_TRUE(ssl_errors::IsHostnameNonUniqueOrDotless("foo.blah"));
 }
+
+TEST(ErrorClassification, LevenshteinDistance) {
+  EXPECT_EQ(0u, GetLevenshteinDistance("banana", "banana"));
+
+  EXPECT_EQ(2u, GetLevenshteinDistance("ab", "ba"));
+  EXPECT_EQ(2u, GetLevenshteinDistance("ba", "ab"));
+
+  EXPECT_EQ(2u, GetLevenshteinDistance("ananas", "banana"));
+  EXPECT_EQ(2u, GetLevenshteinDistance("banana", "ananas"));
+
+  EXPECT_EQ(2u, GetLevenshteinDistance("unclear", "nuclear"));
+  EXPECT_EQ(2u, GetLevenshteinDistance("nuclear", "unclear"));
+
+  EXPECT_EQ(3u, GetLevenshteinDistance("chrome", "chromium"));
+  EXPECT_EQ(3u, GetLevenshteinDistance("chromium", "chrome"));
+
+  EXPECT_EQ(4u, GetLevenshteinDistance("", "abcd"));
+  EXPECT_EQ(4u, GetLevenshteinDistance("abcd", ""));
+
+  EXPECT_EQ(4u, GetLevenshteinDistance("xxx", "xxxxxxx"));
+  EXPECT_EQ(4u, GetLevenshteinDistance("xxxxxxx", "xxx"));
+
+  EXPECT_EQ(7u, GetLevenshteinDistance("yyy", "xxxxxxx"));
+  EXPECT_EQ(7u, GetLevenshteinDistance("xxxxxxx", "yyy"));
+}