Replace RE2 import with a dependency

third_party/re2/re2/testing/required_prefix_test.cc

-// Copyright 2009 The RE2 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 "util/test.h"
-#include "re2/regexp.h"
-
-namespace re2 {
-
-struct PrefixTest {
-  const char* regexp;
-  bool return_value;
-  const char* prefix;
-  bool foldcase;
-  const char* suffix;
-};
-
-static PrefixTest tests[] = {
-  // If the regexp is missing a ^, there's no required prefix.
-  { "abc", false },
-  { "", false },
-  { "(?m)^", false },
-
-  // If the regexp immediately goes into
-  // something not a literal match, there's no required prefix.
-  { "^(abc)", false },
-  { "^a*",  false },
-
-  // Otherwise, it should work.
-  { "^abc$", true, "abc", false, "(?-m:$)" },
-  { "^abc", true, "abc", false, "" },
-  { "^(?i)abc", true, "abc", true, "" },
-  { "^abcd*", true, "abc", false, "d*" },
-  { "^[Aa][Bb]cd*", true, "ab", true, "cd*" },
-  { "^ab[Cc]d*", true, "ab", false, "[Cc]d*" },
-  { "^☺abc", true, "☺abc", false, "" },
-};
-
-TEST(RequiredPrefix, SimpleTests) {
-  for (int i = 0; i < arraysize(tests); i++) {
-    const PrefixTest& t = tests[i];
-    for (int j = 0; j < 2; j++) {
-      Regexp::ParseFlags flags = Regexp::LikePerl;
-      if (j == 0)
-        flags = flags | Regexp::Latin1;
-      Regexp* re = Regexp::Parse(t.regexp, flags, NULL);
-      CHECK(re) << " " << t.regexp;
-      string p;
-      bool f = false;
-      Regexp* s = NULL;
-      CHECK_EQ(t.return_value, re->RequiredPrefix(&p, &f, &s))
-        << " " << t.regexp << " " << (j==0 ? "latin1" : "utf") << " " << re->Dump();
-      if (t.return_value) {
-        CHECK_EQ(p, string(t.prefix))
-          << " " << t.regexp << " " << (j==0 ? "latin1" : "utf");
-        CHECK_EQ(f, t.foldcase)
-          << " " << t.regexp << " " << (j==0 ? "latin1" : "utf");
-        CHECK_EQ(s->ToString(), string(t.suffix))
-          << " " << t.regexp << " " << (j==0 ? "latin1" : "utf");
-        s->Decref();
-      }
-      re->Decref();
-    }
-  }
-}
-
-}  // namespace re2