diff --git a/test/gflags_unittest.cc b/test/gflags_unittest.cc
new file mode 100644
index 0000000..80f7398
--- /dev/null
+++ b/test/gflags_unittest.cc
@@ -0,0 +1,1536 @@
+// Copyright (c) 2005, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// ---
+//
+// For now, this unit test does not cover all features of
+// gflags.cc
+
+#include "config_for_unittests.h"
+#include <gflags/gflags.h>
+
+#include <math.h>       // for isinf() and isnan()
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#ifdef HAVE_UNISTD_H
+#  include <unistd.h>   // for unlink()
+#endif
+#include <vector>
+#include <string>
+#include "util.h"
+TEST_INIT
+EXPECT_DEATH_INIT
+
+// I don't actually use this header file, but #include it under the
+// old location to make sure that the include-header-forwarding
+// works.  But don't bother on windows; the windows port is so new
+// it never had the old location-names.
+#ifndef _MSC_VER
+#include <gflags/gflags_completions.h>
+void (*unused_fn)() = &GFLAGS_NAMESPACE::HandleCommandLineCompletions;
+#endif
+
+using std::string;
+using std::vector;
+using GFLAGS_NAMESPACE::int32;
+using GFLAGS_NAMESPACE::FlagRegisterer;
+using GFLAGS_NAMESPACE::StringFromEnv;
+using GFLAGS_NAMESPACE::RegisterFlagValidator;
+using GFLAGS_NAMESPACE::CommandLineFlagInfo;
+using GFLAGS_NAMESPACE::GetAllFlags;
+
+DEFINE_string(test_tmpdir, "", "Dir we use for temp files");
+DEFINE_string(srcdir, StringFromEnv("SRCDIR", "."), "Source-dir root, needed to find gflags_unittest_flagfile");
+
+DECLARE_string(tryfromenv);   // in gflags.cc
+
+DEFINE_bool(test_bool, false, "tests bool-ness");
+DEFINE_int32(test_int32, -1, "");
+DEFINE_int64(test_int64, -2, "");
+DEFINE_uint64(test_uint64, 2, "");
+DEFINE_double(test_double, -1.0, "");
+DEFINE_string(test_string, "initial", "");
+
+//
+// The below ugliness gets some additional code coverage in the -helpxml
+// and -helpmatch test cases having to do with string lengths and formatting
+//
+DEFINE_bool(test_bool_with_quite_quite_quite_quite_quite_quite_quite_quite_quite_quite_quite_quite_quite_quite_long_name,
+            false,
+            "extremely_extremely_extremely_extremely_extremely_extremely_extremely_extremely_long_meaning");
+
+DEFINE_string(test_str1, "initial", "");
+DEFINE_string(test_str2, "initial", "");
+DEFINE_string(test_str3, "initial", "");
+
+// This is used to test setting tryfromenv manually
+DEFINE_string(test_tryfromenv, "initial", "");
+
+// Don't try this at home!
+static int changeable_var = 12;
+DEFINE_int32(changeable_var, ++changeable_var, "");
+
+static int changeable_bool_var = 8008;
+DEFINE_bool(changeable_bool_var, ++changeable_bool_var == 8009, "");
+
+static int changeable_string_var = 0;
+static string ChangeableString() {
+  char r[] = {static_cast<char>('0' + ++changeable_string_var), '\0'};
+  return r;
+}
+DEFINE_string(changeable_string_var, ChangeableString(), "");
+
+// These are never used in this unittest, but can be used by
+// gflags_unittest.sh when it needs to specify flags
+// that are legal for gflags_unittest but don't need to
+// be a particular value.
+DEFINE_bool(unused_bool, true, "unused bool-ness");
+DEFINE_int32(unused_int32, -1001, "");
+DEFINE_int64(unused_int64, -2001, "");
+DEFINE_uint64(unused_uint64, 2000, "");
+DEFINE_double(unused_double, -1000.0, "");
+DEFINE_string(unused_string, "unused", "");
+
+// These flags are used by gflags_unittest.sh
+DEFINE_bool(changed_bool1, false, "changed");
+DEFINE_bool(changed_bool2, false, "changed");
+DEFINE_bool(long_helpstring, false,
+            "This helpstring goes on forever and ever and ever and ever and "
+            "ever and ever and ever and ever and ever and ever and ever and "
+            "ever and ever and ever and ever and ever and ever and ever and "
+            "ever and ever and ever and ever and ever and ever and ever and "
+            "ever and ever and ever and ever and ever and ever and ever and "
+            "ever and ever and ever and ever and ever and ever and ever and "
+            "ever and ever and ever and ever and ever and ever and ever and "
+            "ever and ever and ever and ever and ever and ever and ever and "
+            "ever and ever and ever and ever and ever and ever and ever and "
+            "ever and ever and ever and ever and ever and ever and ever and "
+            "ever.  This is the end of a long helpstring");
+
+
+static bool AlwaysFail(const char* flag, bool value) { return value == false; }
+DEFINE_bool(always_fail, false, "will fail to validate when you set it");
+DEFINE_validator(always_fail, AlwaysFail);
+
+// See the comment by GetAllFlags in gflags.h
+static bool DeadlockIfCantLockInValidators(const char* flag, bool value) {
+  if (!value) {
+    return true;
+  }
+  vector<CommandLineFlagInfo> dummy;
+  GetAllFlags(&dummy);
+  return true;
+}
+DEFINE_bool(deadlock_if_cant_lock,
+            false,
+            "will deadlock if set to true and "
+            "if locking of registry in validators fails.");
+DEFINE_validator(deadlock_if_cant_lock, DeadlockIfCantLockInValidators);
+
+#define MAKEFLAG(x) DEFINE_int32(test_flag_num##x, x, "Test flag")
+
+// Define 10 flags
+#define MAKEFLAG10(x)                           \
+  MAKEFLAG(x##0);                               \
+  MAKEFLAG(x##1);                               \
+  MAKEFLAG(x##2);                               \
+  MAKEFLAG(x##3);                               \
+  MAKEFLAG(x##4);                               \
+  MAKEFLAG(x##5);                               \
+  MAKEFLAG(x##6);                               \
+  MAKEFLAG(x##7);                               \
+  MAKEFLAG(x##8);                               \
+  MAKEFLAG(x##9)
+
+// Define 100 flags
+#define MAKEFLAG100(x)                          \
+  MAKEFLAG10(x##0);                             \
+  MAKEFLAG10(x##1);                             \
+  MAKEFLAG10(x##2);                             \
+  MAKEFLAG10(x##3);                             \
+  MAKEFLAG10(x##4);                             \
+  MAKEFLAG10(x##5);                             \
+  MAKEFLAG10(x##6);                             \
+  MAKEFLAG10(x##7);                             \
+  MAKEFLAG10(x##8);                             \
+  MAKEFLAG10(x##9)
+
+// Define a bunch of command-line flags.  Each occurrence of the MAKEFLAG100
+// macro defines 100 integer flags.  This lets us test the effect of having
+// many flags on startup time.
+MAKEFLAG100(1);
+MAKEFLAG100(2);
+MAKEFLAG100(3);
+MAKEFLAG100(4);
+MAKEFLAG100(5);
+MAKEFLAG100(6);
+MAKEFLAG100(7);
+MAKEFLAG100(8);
+MAKEFLAG100(9);
+MAKEFLAG100(10);
+MAKEFLAG100(11);
+MAKEFLAG100(12);
+MAKEFLAG100(13);
+MAKEFLAG100(14);
+MAKEFLAG100(15);
+
+#undef MAKEFLAG100
+#undef MAKEFLAG10
+#undef MAKEFLAG
+
+// This is a pseudo-flag -- we want to register a flag with a filename
+// at the top level, but there is no way to do this except by faking
+// the filename.
+namespace fLI {
+  static const int32 FLAGS_nonotldflag1 = 12;
+  int32 FLAGS_tldflag1 = FLAGS_nonotldflag1;
+  int32 FLAGS_notldflag1 = FLAGS_nonotldflag1;
+  static FlagRegisterer o_tldflag1(
+    "tldflag1", "int32",
+    "should show up in --helpshort", "gflags_unittest.cc",
+    &FLAGS_tldflag1, &FLAGS_notldflag1);
+}
+using fLI::FLAGS_tldflag1;
+
+namespace fLI {
+  static const int32 FLAGS_nonotldflag2 = 23;
+  int32 FLAGS_tldflag2 = FLAGS_nonotldflag2;
+  int32 FLAGS_notldflag2 = FLAGS_nonotldflag2;
+  static FlagRegisterer o_tldflag2(
+    "tldflag2", "int32",
+    "should show up in --helpshort", "gflags_unittest.",
+    &FLAGS_tldflag2, &FLAGS_notldflag2);
+}
+using fLI::FLAGS_tldflag2;
+
+namespace GFLAGS_NAMESPACE {
+
+namespace {
+
+
+static string TmpFile(const string& basename) {
+#ifdef _MSC_VER
+  return FLAGS_test_tmpdir + "\\" + basename;
+#else
+  return FLAGS_test_tmpdir + "/" + basename;
+#endif
+}
+
+// Returns the definition of the --flagfile flag to be used in the tests.
+// Must be called after ParseCommandLineFlags().
+static const char* GetFlagFileFlag() {
+#ifdef _MSC_VER
+  static const string flagfile = FLAGS_srcdir + "\\gflags_unittest_flagfile";
+#else
+  static const string flagfile = FLAGS_srcdir + "/gflags_unittest_flagfile";
+#endif
+  static const string flagfile_flag = string("--flagfile=") + flagfile;
+  return flagfile_flag.c_str();
+}
+
+
+// Defining a variable of type CompileAssertTypesEqual<T1, T2> will cause a
+// compiler error iff T1 and T2 are different types.
+template <typename T1, typename T2>
+struct CompileAssertTypesEqual;
+
+template <typename T>
+struct CompileAssertTypesEqual<T, T> {
+};
+
+
+template <typename Expected, typename Actual>
+void AssertIsType(Actual& x) {
+  CompileAssertTypesEqual<Expected, Actual>();
+}
+
+// Verify all the flags are the right type.
+TEST(FlagTypes, FlagTypes) {
+  AssertIsType<bool>(FLAGS_test_bool);
+  AssertIsType<int32>(FLAGS_test_int32);
+  AssertIsType<int64>(FLAGS_test_int64);
+  AssertIsType<uint64>(FLAGS_test_uint64);
+  AssertIsType<double>(FLAGS_test_double);
+  AssertIsType<string>(FLAGS_test_string);
+}
+
+#ifdef GTEST_HAS_DEATH_TEST
+// Death tests for "help" options.
+//
+// The help system automatically calls gflags_exitfunc(1) when you specify any of
+// the help-related flags ("-helpmatch", "-helpxml") so we can't test
+// those mainline.
+
+// Tests that "-helpmatch" causes the process to die.
+TEST(ReadFlagsFromStringDeathTest, HelpMatch) {
+  EXPECT_DEATH(ReadFlagsFromString("-helpmatch=base", GetArgv0(), true),
+               "");
+}
+
+
+// Tests that "-helpxml" causes the process to die.
+TEST(ReadFlagsFromStringDeathTest, HelpXml) {
+  EXPECT_DEATH(ReadFlagsFromString("-helpxml", GetArgv0(), true),
+               "");
+}
+#endif
+
+
+// A subroutine needed for testing reading flags from a string.
+void TestFlagString(const string& flags,
+                    const string& expected_string,
+                    bool expected_bool,
+                    int32 expected_int32,
+                    double expected_double) {
+  EXPECT_TRUE(ReadFlagsFromString(flags,
+                                  GetArgv0(),
+                                  // errors are fatal
+                                  true));
+
+  EXPECT_EQ(expected_string, FLAGS_test_string);
+  EXPECT_EQ(expected_bool, FLAGS_test_bool);
+  EXPECT_EQ(expected_int32, FLAGS_test_int32);
+  EXPECT_DOUBLE_EQ(expected_double, FLAGS_test_double);
+}
+
+
+// Tests reading flags from a string.
+TEST(FlagFileTest, ReadFlagsFromString) {
+  TestFlagString(
+      // Flag string
+      "-test_string=continued\n"
+      "# some comments are in order\n"
+      "# some\n"
+      "  # comments\n"
+      "#are\n"
+      "                  #trickier\n"
+      "# than others\n"
+      "-test_bool=true\n"
+      "     -test_int32=1\n"
+      "-test_double=0.0\n",
+      // Expected values
+      "continued",
+      true,
+      1,
+      0.0);
+
+  TestFlagString(
+      // Flag string
+      "# let's make sure it can update values\n"
+      "-test_string=initial\n"
+      "-test_bool=false\n"
+      "-test_int32=123\n"
+      "-test_double=123.0\n",
+      // Expected values
+      "initial",
+      false,
+      123,
+      123.0);
+}
+
+// Tests the filename part of the flagfile
+TEST(FlagFileTest, FilenamesOurfileLast) {
+  FLAGS_test_string = "initial";
+  FLAGS_test_bool = false;
+  FLAGS_test_int32 = -1;
+  FLAGS_test_double = -1.0;
+  TestFlagString(
+      // Flag string
+      "-test_string=continued\n"
+      "# some comments are in order\n"
+      "# some\n"
+      "  # comments\n"
+      "#are\n"
+      "                  #trickier\n"
+      "# than others\n"
+      "not_our_filename\n"
+      "-test_bool=true\n"
+      "     -test_int32=1\n"
+      "gflags_unittest\n"
+      "-test_double=1000.0\n",
+      // Expected values
+      "continued",
+      false,
+      -1,
+      1000.0);
+}
+
+TEST(FlagFileTest, FilenamesOurfileFirst) {
+  FLAGS_test_string = "initial";
+  FLAGS_test_bool = false;
+  FLAGS_test_int32 = -1;
+  FLAGS_test_double = -1.0;
+  TestFlagString(
+      // Flag string
+      "-test_string=continued\n"
+      "# some comments are in order\n"
+      "# some\n"
+      "  # comments\n"
+      "#are\n"
+      "                  #trickier\n"
+      "# than others\n"
+      "gflags_unittest\n"
+      "-test_bool=true\n"
+      "     -test_int32=1\n"
+      "not_our_filename\n"
+      "-test_double=1000.0\n",
+      // Expected values
+      "continued",
+      true,
+      1,
+      -1.0);
+}
+
+#if defined(HAVE_FNMATCH_H) || defined(HAVE_SHLWAPI_H)  // otherwise glob isn't supported
+TEST(FlagFileTest, FilenamesOurfileGlob) {
+  FLAGS_test_string = "initial";
+  FLAGS_test_bool = false;
+  FLAGS_test_int32 = -1;
+  FLAGS_test_double = -1.0;
+  TestFlagString(
+      // Flag string
+      "-test_string=continued\n"
+      "# some comments are in order\n"
+      "# some\n"
+      "  # comments\n"
+      "#are\n"
+      "                  #trickier\n"
+      "# than others\n"
+      "*flags*\n"
+      "-test_bool=true\n"
+      "     -test_int32=1\n"
+      "flags\n"
+      "-test_double=1000.0\n",
+      // Expected values
+      "continued",
+      true,
+      1,
+      -1.0);
+}
+
+TEST(FlagFileTest, FilenamesOurfileInBigList) {
+  FLAGS_test_string = "initial";
+  FLAGS_test_bool = false;
+  FLAGS_test_int32 = -1;
+  FLAGS_test_double = -1.0;
+  TestFlagString(
+      // Flag string
+      "-test_string=continued\n"
+      "# some comments are in order\n"
+      "# some\n"
+      "  # comments\n"
+      "#are\n"
+      "                  #trickier\n"
+      "# than others\n"
+      "*first* *flags* *third*\n"
+      "-test_bool=true\n"
+      "     -test_int32=1\n"
+      "flags\n"
+      "-test_double=1000.0\n",
+      // Expected values
+      "continued",
+      true,
+      1,
+      -1.0);
+}
+#endif  // defined(HAVE_FNMATCH_H) || defined(HAVE_SHLWAPI_H)
+
+// Tests that a failed flag-from-string read keeps flags at default values
+TEST(FlagFileTest, FailReadFlagsFromString) {
+  FLAGS_test_int32 = 119;
+  string flags("# let's make sure it can update values\n"
+               "-test_string=non_initial\n"
+               "-test_bool=false\n"
+               "-test_int32=123\n"
+               "-test_double=illegal\n");
+
+  EXPECT_FALSE(ReadFlagsFromString(flags,
+                                   GetArgv0(),
+                                   // errors are fatal
+                                   false));
+
+  EXPECT_EQ(119, FLAGS_test_int32);
+  EXPECT_EQ("initial", FLAGS_test_string);
+}
+
+// Tests that flags can be set to ordinary values.
+TEST(SetFlagValueTest, OrdinaryValues) {
+  EXPECT_EQ("initial", FLAGS_test_str1);
+
+  SetCommandLineOptionWithMode("test_str1", "second", SET_FLAG_IF_DEFAULT);
+  EXPECT_EQ("second", FLAGS_test_str1);  // set; was default
+
+  SetCommandLineOptionWithMode("test_str1", "third", SET_FLAG_IF_DEFAULT);
+  EXPECT_EQ("second", FLAGS_test_str1);  // already set once
+
+  FLAGS_test_str1 = "initial";
+  SetCommandLineOptionWithMode("test_str1", "third", SET_FLAG_IF_DEFAULT);
+  EXPECT_EQ("initial", FLAGS_test_str1);  // still already set before
+
+  SetCommandLineOptionWithMode("test_str1", "third", SET_FLAGS_VALUE);
+  EXPECT_EQ("third", FLAGS_test_str1);  // changed value
+
+  SetCommandLineOptionWithMode("test_str1", "fourth", SET_FLAGS_DEFAULT);
+  EXPECT_EQ("third", FLAGS_test_str1);
+  // value not changed (already set before)
+
+  EXPECT_EQ("initial", FLAGS_test_str2);
+
+  SetCommandLineOptionWithMode("test_str2", "second", SET_FLAGS_DEFAULT);
+  EXPECT_EQ("second", FLAGS_test_str2);  // changed (was default)
+
+  FLAGS_test_str2 = "extra";
+  EXPECT_EQ("extra", FLAGS_test_str2);
+
+  FLAGS_test_str2 = "second";
+  SetCommandLineOptionWithMode("test_str2", "third", SET_FLAGS_DEFAULT);
+  EXPECT_EQ("third", FLAGS_test_str2);  // still changed (was equal to default)
+
+  SetCommandLineOptionWithMode("test_str2", "fourth", SET_FLAG_IF_DEFAULT);
+  EXPECT_EQ("fourth", FLAGS_test_str2);  // changed (was default)
+
+  EXPECT_EQ("initial", FLAGS_test_str3);
+
+  SetCommandLineOptionWithMode("test_str3", "second", SET_FLAGS_DEFAULT);
+  EXPECT_EQ("second", FLAGS_test_str3);  // changed
+
+  FLAGS_test_str3 = "third";
+  SetCommandLineOptionWithMode("test_str3", "fourth", SET_FLAGS_DEFAULT);
+  EXPECT_EQ("third", FLAGS_test_str3);  // not changed (was set)
+
+  SetCommandLineOptionWithMode("test_str3", "fourth", SET_FLAG_IF_DEFAULT);
+  EXPECT_EQ("third", FLAGS_test_str3);  // not changed (was set)
+
+  SetCommandLineOptionWithMode("test_str3", "fourth", SET_FLAGS_VALUE);
+  EXPECT_EQ("fourth", FLAGS_test_str3);  // changed value
+}
+
+
+// Tests that flags can be set to exceptional values.
+// Note: apparently MINGW doesn't parse inf and nan correctly:
+//    http://www.mail-archive.com/bug-gnulib@gnu.org/msg09573.html
+// This url says FreeBSD also has a problem, but I didn't see that.
+TEST(SetFlagValueTest, ExceptionalValues) {
+#if defined(isinf) && !defined(__MINGW32__)
+  EXPECT_EQ("test_double set to inf\n",
+            SetCommandLineOption("test_double", "inf"));
+  EXPECT_INF(FLAGS_test_double);
+
+  EXPECT_EQ("test_double set to inf\n",
+            SetCommandLineOption("test_double", "INF"));
+  EXPECT_INF(FLAGS_test_double);
+#endif
+
+  // set some bad values
+  EXPECT_EQ("",
+            SetCommandLineOption("test_double", "0.1xxx"));
+  EXPECT_EQ("",
+            SetCommandLineOption("test_double", " "));
+  EXPECT_EQ("",
+            SetCommandLineOption("test_double", ""));
+#if defined(isinf) && !defined(__MINGW32__)
+  EXPECT_EQ("test_double set to -inf\n",
+            SetCommandLineOption("test_double", "-inf"));
+  EXPECT_INF(FLAGS_test_double);
+  EXPECT_GT(0, FLAGS_test_double);
+#endif
+
+#if defined(isnan) && !defined(__MINGW32__)
+  EXPECT_EQ("test_double set to nan\n",
+            SetCommandLineOption("test_double", "NaN"));
+  EXPECT_NAN(FLAGS_test_double);
+#endif
+}
+
+// Tests that integer flags can be specified in many ways
+TEST(SetFlagValueTest, DifferentRadices) {
+  EXPECT_EQ("test_int32 set to 12\n",
+            SetCommandLineOption("test_int32", "12"));
+
+  EXPECT_EQ("test_int32 set to 16\n",
+            SetCommandLineOption("test_int32", "0x10"));
+
+  EXPECT_EQ("test_int32 set to 34\n",
+            SetCommandLineOption("test_int32", "0X22"));
+
+  // Leading 0 is *not* octal; it's still decimal
+  EXPECT_EQ("test_int32 set to 10\n",
+            SetCommandLineOption("test_int32", "010"));
+}
+
+// Tests what happens when you try to set a flag to an illegal value
+TEST(SetFlagValueTest, IllegalValues) {
+  FLAGS_test_bool = true;
+  FLAGS_test_int32 = 119;
+  FLAGS_test_int64 = 1191;
+  FLAGS_test_uint64 = 11911;
+
+  EXPECT_EQ("",
+            SetCommandLineOption("test_bool", "12"));
+
+  EXPECT_EQ("",
+            SetCommandLineOption("test_int32", "7000000000000"));
+
+  EXPECT_EQ("",
+            SetCommandLineOption("test_uint64", "-1"));
+
+  EXPECT_EQ("",
+            SetCommandLineOption("test_int64", "not a number!"));
+
+  // Test the empty string with each type of input
+  EXPECT_EQ("", SetCommandLineOption("test_bool", ""));
+  EXPECT_EQ("", SetCommandLineOption("test_int32", ""));
+  EXPECT_EQ("", SetCommandLineOption("test_int64", ""));
+  EXPECT_EQ("", SetCommandLineOption("test_uint64", ""));
+  EXPECT_EQ("", SetCommandLineOption("test_double", ""));
+  EXPECT_EQ("test_string set to \n", SetCommandLineOption("test_string", ""));
+
+  EXPECT_TRUE(FLAGS_test_bool);
+  EXPECT_EQ(119, FLAGS_test_int32);
+  EXPECT_EQ(1191, FLAGS_test_int64);
+  EXPECT_EQ(11911, FLAGS_test_uint64);
+}
+
+
+// Tests that we only evaluate macro args once
+TEST(MacroArgs, EvaluateOnce) {
+  EXPECT_EQ(13, FLAGS_changeable_var);
+  // Make sure we don't ++ the value somehow, when evaluating the flag.
+  EXPECT_EQ(13, FLAGS_changeable_var);
+  // Make sure the macro only evaluated this var once.
+  EXPECT_EQ(13, changeable_var);
+  // Make sure the actual value and default value are the same
+  SetCommandLineOptionWithMode("changeable_var", "21", SET_FLAG_IF_DEFAULT);
+  EXPECT_EQ(21, FLAGS_changeable_var);
+}
+
+TEST(MacroArgs, EvaluateOnceBool) {
+  EXPECT_TRUE(FLAGS_changeable_bool_var);
+  EXPECT_TRUE(FLAGS_changeable_bool_var);
+  EXPECT_EQ(8009, changeable_bool_var);
+  SetCommandLineOptionWithMode("changeable_bool_var", "false",
+                               SET_FLAG_IF_DEFAULT);
+  EXPECT_FALSE(FLAGS_changeable_bool_var);
+}
+
+TEST(MacroArgs, EvaluateOnceStrings) {
+  EXPECT_EQ("1", FLAGS_changeable_string_var);
+  EXPECT_EQ("1", FLAGS_changeable_string_var);
+  EXPECT_EQ(1, changeable_string_var);
+  SetCommandLineOptionWithMode("changeable_string_var", "different",
+                               SET_FLAG_IF_DEFAULT);
+  EXPECT_EQ("different", FLAGS_changeable_string_var);
+}
+
+// Tests that the FooFromEnv does the right thing
+TEST(FromEnvTest, LegalValues) {
+  setenv("BOOL_VAL1", "true", 1);
+  setenv("BOOL_VAL2", "false", 1);
+  setenv("BOOL_VAL3", "1", 1);
+  setenv("BOOL_VAL4", "F", 1);
+  EXPECT_TRUE(BoolFromEnv("BOOL_VAL1", false));
+  EXPECT_FALSE(BoolFromEnv("BOOL_VAL2", true));
+  EXPECT_TRUE(BoolFromEnv("BOOL_VAL3", false));
+  EXPECT_FALSE(BoolFromEnv("BOOL_VAL4", true));
+  EXPECT_TRUE(BoolFromEnv("BOOL_VAL_UNKNOWN", true));
+  EXPECT_FALSE(BoolFromEnv("BOOL_VAL_UNKNOWN", false));
+
+  setenv("INT_VAL1", "1", 1);
+  setenv("INT_VAL2", "-1", 1);
+  EXPECT_EQ(1, Int32FromEnv("INT_VAL1", 10));
+  EXPECT_EQ(-1, Int32FromEnv("INT_VAL2", 10));
+  EXPECT_EQ(10, Int32FromEnv("INT_VAL_UNKNOWN", 10));
+
+  setenv("INT_VAL3", "1099511627776", 1);
+  EXPECT_EQ(1, Int64FromEnv("INT_VAL1", 20));
+  EXPECT_EQ(-1, Int64FromEnv("INT_VAL2", 20));
+  EXPECT_EQ(1099511627776LL, Int64FromEnv("INT_VAL3", 20));
+  EXPECT_EQ(20, Int64FromEnv("INT_VAL_UNKNOWN", 20));
+
+  EXPECT_EQ(1, Uint64FromEnv("INT_VAL1", 30));
+  EXPECT_EQ(1099511627776ULL, Uint64FromEnv("INT_VAL3", 30));
+  EXPECT_EQ(30, Uint64FromEnv("INT_VAL_UNKNOWN", 30));
+
+  // I pick values here that can be easily represented exactly in floating-point
+  setenv("DOUBLE_VAL1", "0.0", 1);
+  setenv("DOUBLE_VAL2", "1.0", 1);
+  setenv("DOUBLE_VAL3", "-1.0", 1);
+  EXPECT_EQ(0.0, DoubleFromEnv("DOUBLE_VAL1", 40.0));
+  EXPECT_EQ(1.0, DoubleFromEnv("DOUBLE_VAL2", 40.0));
+  EXPECT_EQ(-1.0, DoubleFromEnv("DOUBLE_VAL3", 40.0));
+  EXPECT_EQ(40.0, DoubleFromEnv("DOUBLE_VAL_UNKNOWN", 40.0));
+
+  setenv("STRING_VAL1", "", 1);
+  setenv("STRING_VAL2", "my happy string!", 1);
+  EXPECT_STREQ("", StringFromEnv("STRING_VAL1", "unknown"));
+  EXPECT_STREQ("my happy string!", StringFromEnv("STRING_VAL2", "unknown"));
+  EXPECT_STREQ("unknown", StringFromEnv("STRING_VAL_UNKNOWN", "unknown"));
+}
+
+#ifdef GTEST_HAS_DEATH_TEST
+// Tests that the FooFromEnv dies on parse-error
+TEST(FromEnvDeathTest, IllegalValues) {
+  setenv("BOOL_BAD1", "so true!", 1);
+  setenv("BOOL_BAD2", "", 1);
+  EXPECT_DEATH(BoolFromEnv("BOOL_BAD1", false), "error parsing env variable");
+  EXPECT_DEATH(BoolFromEnv("BOOL_BAD2", true), "error parsing env variable");
+
+  setenv("INT_BAD1", "one", 1);
+  setenv("INT_BAD2", "100000000000000000", 1);
+  setenv("INT_BAD3", "0xx10", 1);
+  setenv("INT_BAD4", "", 1);
+  EXPECT_DEATH(Int32FromEnv("INT_BAD1", 10), "error parsing env variable");
+  EXPECT_DEATH(Int32FromEnv("INT_BAD2", 10), "error parsing env variable");
+  EXPECT_DEATH(Int32FromEnv("INT_BAD3", 10), "error parsing env variable");
+  EXPECT_DEATH(Int32FromEnv("INT_BAD4", 10), "error parsing env variable");
+
+  setenv("BIGINT_BAD1", "18446744073709551616000", 1);
+  EXPECT_DEATH(Int64FromEnv("INT_BAD1", 20), "error parsing env variable");
+  EXPECT_DEATH(Int64FromEnv("INT_BAD3", 20), "error parsing env variable");
+  EXPECT_DEATH(Int64FromEnv("INT_BAD4", 20), "error parsing env variable");
+  EXPECT_DEATH(Int64FromEnv("BIGINT_BAD1", 200), "error parsing env variable");
+
+  setenv("BIGINT_BAD2", "-1", 1);
+  EXPECT_DEATH(Uint64FromEnv("INT_BAD1", 30), "error parsing env variable");
+  EXPECT_DEATH(Uint64FromEnv("INT_BAD3", 30), "error parsing env variable");
+  EXPECT_DEATH(Uint64FromEnv("INT_BAD4", 30), "error parsing env variable");
+  EXPECT_DEATH(Uint64FromEnv("BIGINT_BAD1", 30), "error parsing env variable");
+  // TODO(csilvers): uncomment this when we disallow negative numbers for uint64
+#if 0
+  EXPECT_DEATH(Uint64FromEnv("BIGINT_BAD2", 30), "error parsing env variable");
+#endif
+
+  setenv("DOUBLE_BAD1", "0.0.0", 1);
+  setenv("DOUBLE_BAD2", "", 1);
+  EXPECT_DEATH(DoubleFromEnv("DOUBLE_BAD1", 40.0), "error parsing env variable");
+  EXPECT_DEATH(DoubleFromEnv("DOUBLE_BAD2", 40.0), "error parsing env variable");
+}
+#endif
+
+
+// Tests that FlagSaver can save the states of string flags.
+TEST(FlagSaverTest, CanSaveStringFlagStates) {
+  // 1. Initializes the flags.
+
+  // State of flag test_str1:
+  //   default value - "initial"
+  //   current value - "initial"
+  //   not set       - true
+
+  SetCommandLineOptionWithMode("test_str2", "second", SET_FLAGS_VALUE);
+  // State of flag test_str2:
+  //   default value - "initial"
+  //   current value - "second"
+  //   not set       - false
+
+  SetCommandLineOptionWithMode("test_str3", "second", SET_FLAGS_DEFAULT);
+  // State of flag test_str3:
+  //   default value - "second"
+  //   current value - "second"
+  //   not set       - true
+
+  // 2. Saves the flag states.
+
+  {
+    FlagSaver fs;
+
+    // 3. Modifies the flag states.
+
+    SetCommandLineOptionWithMode("test_str1", "second", SET_FLAGS_VALUE);
+    EXPECT_EQ("second", FLAGS_test_str1);
+    // State of flag test_str1:
+    //   default value - "second"
+    //   current value - "second"
+    //   not set       - true
+
+    SetCommandLineOptionWithMode("test_str2", "third", SET_FLAGS_DEFAULT);
+    EXPECT_EQ("second", FLAGS_test_str2);
+    // State of flag test_str2:
+    //   default value - "third"
+    //   current value - "second"
+    //   not set       - false
+
+    SetCommandLineOptionWithMode("test_str3", "third", SET_FLAGS_VALUE);
+    EXPECT_EQ("third", FLAGS_test_str3);
+    // State of flag test_str1:
+    //   default value - "second"
+    //   current value - "third"
+    //   not set       - false
+
+    // 4. Restores the flag states.
+  }
+
+  // 5. Verifies that the states were restored.
+
+  // Verifies that the value of test_str1 was restored.
+  EXPECT_EQ("initial", FLAGS_test_str1);
+  // Verifies that the "not set" attribute of test_str1 was restored to true.
+  SetCommandLineOptionWithMode("test_str1", "second", SET_FLAG_IF_DEFAULT);
+  EXPECT_EQ("second", FLAGS_test_str1);
+
+  // Verifies that the value of test_str2 was restored.
+  EXPECT_EQ("second", FLAGS_test_str2);
+  // Verifies that the "not set" attribute of test_str2 was restored to false.
+  SetCommandLineOptionWithMode("test_str2", "fourth", SET_FLAG_IF_DEFAULT);
+  EXPECT_EQ("second", FLAGS_test_str2);
+
+  // Verifies that the value of test_str3 was restored.
+  EXPECT_EQ("second", FLAGS_test_str3);
+  // Verifies that the "not set" attribute of test_str3 was restored to true.
+  SetCommandLineOptionWithMode("test_str3", "fourth", SET_FLAG_IF_DEFAULT);
+  EXPECT_EQ("fourth", FLAGS_test_str3);
+}
+
+
+// Tests that FlagSaver can save the values of various-typed flags.
+TEST(FlagSaverTest, CanSaveVariousTypedFlagValues) {
+  // Initializes the flags.
+  FLAGS_test_bool = false;
+  FLAGS_test_int32 = -1;
+  FLAGS_test_int64 = -2;
+  FLAGS_test_uint64 = 3;
+  FLAGS_test_double = 4.0;
+  FLAGS_test_string = "good";
+
+  // Saves the flag states.
+  {
+    FlagSaver fs;
+
+    // Modifies the flags.
+    FLAGS_test_bool = true;
+    FLAGS_test_int32 = -5;
+    FLAGS_test_int64 = -6;
+    FLAGS_test_uint64 = 7;
+    FLAGS_test_double = 8.0;
+    FLAGS_test_string = "bad";
+
+    // Restores the flag states.
+  }
+
+  // Verifies the flag values were restored.
+  EXPECT_FALSE(FLAGS_test_bool);
+  EXPECT_EQ(-1, FLAGS_test_int32);
+  EXPECT_EQ(-2, FLAGS_test_int64);
+  EXPECT_EQ(3, FLAGS_test_uint64);
+  EXPECT_DOUBLE_EQ(4.0, FLAGS_test_double);
+  EXPECT_EQ("good", FLAGS_test_string);
+}
+
+TEST(GetAllFlagsTest, BaseTest) {
+  vector<CommandLineFlagInfo> flags;
+  GetAllFlags(&flags);
+  bool found_test_bool = false;
+  vector<CommandLineFlagInfo>::const_iterator i;
+  for (i = flags.begin(); i != flags.end(); ++i) {
+    if (i->name == "test_bool") {
+      found_test_bool = true;
+      EXPECT_EQ(i->type, "bool");
+      EXPECT_EQ(i->default_value, "false");
+      EXPECT_EQ(i->flag_ptr, &FLAGS_test_bool);
+      break;
+    }
+  }
+  EXPECT_TRUE(found_test_bool);
+}
+
+TEST(ShowUsageWithFlagsTest, BaseTest) {
+  // TODO(csilvers): test this by allowing output other than to stdout.
+  // Not urgent since this functionality is tested via
+  // gflags_unittest.sh, though only through use of --help.
+}
+
+TEST(ShowUsageWithFlagsRestrictTest, BaseTest) {
+  // TODO(csilvers): test this by allowing output other than to stdout.
+  // Not urgent since this functionality is tested via
+  // gflags_unittest.sh, though only through use of --helpmatch.
+}
+
+// Note: all these argv-based tests depend on SetArgv being called
+// before ParseCommandLineFlags() in main(), below.
+TEST(GetArgvsTest, BaseTest) {
+  vector<string> argvs = GetArgvs();
+  EXPECT_EQ(4, argvs.size());
+  EXPECT_EQ("/test/argv/for/gflags_unittest", argvs[0]);
+  EXPECT_EQ("argv 2", argvs[1]);
+  EXPECT_EQ("3rd argv", argvs[2]);
+  EXPECT_EQ("argv #4", argvs[3]);
+}
+
+TEST(GetArgvTest, BaseTest) {
+  EXPECT_STREQ("/test/argv/for/gflags_unittest "
+               "argv 2 3rd argv argv #4", GetArgv());
+}
+
+TEST(GetArgv0Test, BaseTest) {
+  EXPECT_STREQ("/test/argv/for/gflags_unittest", GetArgv0());
+}
+
+TEST(GetArgvSumTest, BaseTest) {
+  // This number is just the sum of the ASCII values of all the chars
+  // in GetArgv().
+  EXPECT_EQ(4904, GetArgvSum());
+}
+
+TEST(ProgramInvocationNameTest, BaseTest) {
+  EXPECT_STREQ("/test/argv/for/gflags_unittest",
+               ProgramInvocationName());
+}
+
+TEST(ProgramInvocationShortNameTest, BaseTest) {
+  EXPECT_STREQ("gflags_unittest", ProgramInvocationShortName());
+}
+
+TEST(ProgramUsageTest, BaseTest) {  // Depends on 1st arg to ParseCommandLineFlags()
+  EXPECT_STREQ("/test/argv/for/gflags_unittest: "
+               "<useless flag> [...]\nDoes something useless.\n",
+               ProgramUsage());
+}
+
+TEST(GetCommandLineOptionTest, NameExistsAndIsDefault) {
+  string value("will be changed");
+  bool r = GetCommandLineOption("test_bool", &value);
+  EXPECT_TRUE(r);
+  EXPECT_EQ("false", value);
+
+  r = GetCommandLineOption("test_int32", &value);
+  EXPECT_TRUE(r);
+  EXPECT_EQ("-1", value);
+}
+
+TEST(GetCommandLineOptionTest, NameExistsAndWasAssigned) {
+  FLAGS_test_int32 = 400;
+  string value("will be changed");
+  const bool r = GetCommandLineOption("test_int32", &value);
+  EXPECT_TRUE(r);
+  EXPECT_EQ("400", value);
+}
+
+TEST(GetCommandLineOptionTest, NameExistsAndWasSet) {
+  SetCommandLineOption("test_int32", "700");
+  string value("will be changed");
+  const bool r = GetCommandLineOption("test_int32", &value);
+  EXPECT_TRUE(r);
+  EXPECT_EQ("700", value);
+}
+
+TEST(GetCommandLineOptionTest, NameExistsAndWasNotSet) {
+  // This doesn't set the flag's value, but rather its default value.
+  // is_default is still true, but the 'default' value returned has changed!
+  SetCommandLineOptionWithMode("test_int32", "800", SET_FLAGS_DEFAULT);
+  string value("will be changed");
+  const bool r = GetCommandLineOption("test_int32", &value);
+  EXPECT_TRUE(r);
+  EXPECT_EQ("800", value);
+  EXPECT_TRUE(GetCommandLineFlagInfoOrDie("test_int32").is_default);
+}
+
+TEST(GetCommandLineOptionTest, NameExistsAndWasConditionallySet) {
+  SetCommandLineOptionWithMode("test_int32", "900", SET_FLAG_IF_DEFAULT);
+  string value("will be changed");
+  const bool r = GetCommandLineOption("test_int32", &value);
+  EXPECT_TRUE(r);
+  EXPECT_EQ("900", value);
+}
+
+TEST(GetCommandLineOptionTest, NameDoesNotExist) {
+  string value("will not be changed");
+  const bool r = GetCommandLineOption("test_int3210", &value);
+  EXPECT_FALSE(r);
+  EXPECT_EQ("will not be changed", value);
+}
+
+TEST(GetCommandLineFlagInfoTest, FlagExists) {
+  CommandLineFlagInfo info;
+  bool r = GetCommandLineFlagInfo("test_int32", &info);
+  EXPECT_TRUE(r);
+  EXPECT_EQ("test_int32", info.name);
+  EXPECT_EQ("int32", info.type);
+  EXPECT_EQ("", info.description);
+  EXPECT_EQ("-1", info.current_value);
+  EXPECT_EQ("-1", info.default_value);
+  EXPECT_TRUE(info.is_default);
+  EXPECT_FALSE(info.has_validator_fn);
+  EXPECT_EQ(&FLAGS_test_int32, info.flag_ptr);
+
+  FLAGS_test_bool = true;
+  r = GetCommandLineFlagInfo("test_bool", &info);
+  EXPECT_TRUE(r);
+  EXPECT_EQ("test_bool", info.name);
+  EXPECT_EQ("bool", info.type);
+  EXPECT_EQ("tests bool-ness", info.description);
+  EXPECT_EQ("true", info.current_value);
+  EXPECT_EQ("false", info.default_value);
+  EXPECT_FALSE(info.is_default);
+  EXPECT_FALSE(info.has_validator_fn);
+  EXPECT_EQ(&FLAGS_test_bool, info.flag_ptr);
+
+  FLAGS_test_bool = false;
+  r = GetCommandLineFlagInfo("test_bool", &info);
+  EXPECT_TRUE(r);
+  EXPECT_EQ("test_bool", info.name);
+  EXPECT_EQ("bool", info.type);
+  EXPECT_EQ("tests bool-ness", info.description);
+  EXPECT_EQ("false", info.current_value);
+  EXPECT_EQ("false", info.default_value);
+  EXPECT_FALSE(info.is_default);  // value is same, but flag *was* modified
+  EXPECT_FALSE(info.has_validator_fn);
+  EXPECT_EQ(&FLAGS_test_bool, info.flag_ptr);
+}
+
+TEST(GetCommandLineFlagInfoTest, FlagDoesNotExist) {
+  CommandLineFlagInfo info;
+  // Set to some random values that GetCommandLineFlagInfo should not change
+  info.name = "name";
+  info.type = "type";
+  info.current_value = "curr";
+  info.default_value = "def";
+  info.filename = "/";
+  info.is_default = false;
+  info.has_validator_fn = true;
+  info.flag_ptr = NULL;
+  bool r = GetCommandLineFlagInfo("test_int3210", &info);
+  EXPECT_FALSE(r);
+  EXPECT_EQ("name", info.name);
+  EXPECT_EQ("type", info.type);
+  EXPECT_EQ("", info.description);
+  EXPECT_EQ("curr", info.current_value);
+  EXPECT_EQ("def", info.default_value);
+  EXPECT_EQ("/", info.filename);
+  EXPECT_FALSE(info.is_default);
+  EXPECT_TRUE(info.has_validator_fn);
+  EXPECT_EQ(NULL, info.flag_ptr);
+}
+
+TEST(GetCommandLineFlagInfoOrDieTest, FlagExistsAndIsDefault) {
+  CommandLineFlagInfo info;
+  info = GetCommandLineFlagInfoOrDie("test_int32");
+  EXPECT_EQ("test_int32", info.name);
+  EXPECT_EQ("int32", info.type);
+  EXPECT_EQ("", info.description);
+  EXPECT_EQ("-1", info.current_value);
+  EXPECT_EQ("-1", info.default_value);
+  EXPECT_TRUE(info.is_default);
+  EXPECT_EQ(&FLAGS_test_int32, info.flag_ptr);
+  info = GetCommandLineFlagInfoOrDie("test_bool");
+  EXPECT_EQ("test_bool", info.name);
+  EXPECT_EQ("bool", info.type);
+  EXPECT_EQ("tests bool-ness", info.description);
+  EXPECT_EQ("false", info.current_value);
+  EXPECT_EQ("false", info.default_value);
+  EXPECT_TRUE(info.is_default);
+  EXPECT_FALSE(info.has_validator_fn);
+  EXPECT_EQ(&FLAGS_test_bool, info.flag_ptr);
+}
+
+TEST(GetCommandLineFlagInfoOrDieTest, FlagExistsAndWasAssigned) {
+  FLAGS_test_int32 = 400;
+  CommandLineFlagInfo info;
+  info = GetCommandLineFlagInfoOrDie("test_int32");
+  EXPECT_EQ("test_int32", info.name);
+  EXPECT_EQ("int32", info.type);
+  EXPECT_EQ("", info.description);
+  EXPECT_EQ("400", info.current_value);
+  EXPECT_EQ("-1", info.default_value);
+  EXPECT_FALSE(info.is_default);
+  EXPECT_EQ(&FLAGS_test_int32, info.flag_ptr);
+  FLAGS_test_bool = true;
+  info = GetCommandLineFlagInfoOrDie("test_bool");
+  EXPECT_EQ("test_bool", info.name);
+  EXPECT_EQ("bool", info.type);
+  EXPECT_EQ("tests bool-ness", info.description);
+  EXPECT_EQ("true", info.current_value);
+  EXPECT_EQ("false", info.default_value);
+  EXPECT_FALSE(info.is_default);
+  EXPECT_FALSE(info.has_validator_fn);
+  EXPECT_EQ(&FLAGS_test_bool, info.flag_ptr);
+}
+
+#ifdef GTEST_HAS_DEATH_TEST
+TEST(GetCommandLineFlagInfoOrDieDeathTest, FlagDoesNotExist) {
+  EXPECT_DEATH(GetCommandLineFlagInfoOrDie("test_int3210"),
+               ".*: flag test_int3210 does not exist");
+}
+#endif
+
+
+// These are lightly tested because they're deprecated.  Basically,
+// the tests are meant to cover how existing users use these functions,
+// but not necessarily how new users could use them.
+TEST(DeprecatedFunctionsTest, CommandlineFlagsIntoString) {
+  string s = CommandlineFlagsIntoString();
+  EXPECT_NE(string::npos, s.find("--test_bool="));
+}
+
+TEST(DeprecatedFunctionsTest, AppendFlagsIntoFile) {
+  FLAGS_test_int32 = 10;     // just to make the test more interesting
+  string filename(TmpFile("flagfile"));
+  unlink(filename.c_str());  // just to be safe
+  const bool r = AppendFlagsIntoFile(filename, "not the real argv0");
+  EXPECT_TRUE(r);
+
+  FILE* fp;
+  EXPECT_EQ(0, SafeFOpen(&fp, filename.c_str(), "r"));
+  EXPECT_TRUE(fp != NULL);
+  char line[8192];
+  EXPECT_TRUE(fgets(line, sizeof(line)-1, fp) != NULL);  // get the first line
+  // First line should be progname.
+  EXPECT_STREQ("not the real argv0\n", line);
+
+  bool found_bool = false, found_int32 = false;
+  while (fgets(line, sizeof(line)-1, fp)) {
+    line[sizeof(line)-1] = '\0';    // just to be safe
+    if (strcmp(line, "--test_bool=false\n") == 0)
+      found_bool = true;
+    if (strcmp(line, "--test_int32=10\n") == 0)
+      found_int32 = true;
+  }
+  EXPECT_TRUE(found_int32);
+  EXPECT_TRUE(found_bool);
+  fclose(fp);
+}
+
+TEST(DeprecatedFunctionsTest, ReadFromFlagsFile) {
+  FLAGS_test_int32 = -10;    // just to make the test more interesting
+  string filename(TmpFile("flagfile2"));
+  unlink(filename.c_str());  // just to be safe
+  bool r = AppendFlagsIntoFile(filename, GetArgv0());
+  EXPECT_TRUE(r);
+
+  FLAGS_test_int32 = -11;
+  r = ReadFromFlagsFile(filename, GetArgv0(), true);
+  EXPECT_TRUE(r);
+  EXPECT_EQ(-10, FLAGS_test_int32);
+}  // unnamed namespace
+
+TEST(DeprecatedFunctionsTest, ReadFromFlagsFileFailure) {
+  FLAGS_test_int32 = -20;
+  string filename(TmpFile("flagfile3"));
+  FILE* fp;
+  EXPECT_EQ(0, SafeFOpen(&fp, filename.c_str(), "w"));
+  EXPECT_TRUE(fp != NULL);
+  // Note the error in the bool assignment below...
+  fprintf(fp, "%s\n--test_int32=-21\n--test_bool=not_a_bool!\n", GetArgv0());
+  fclose(fp);
+
+  FLAGS_test_int32 = -22;
+  const bool r = ReadFromFlagsFile(filename, GetArgv0(), false);
+  EXPECT_FALSE(r);
+  EXPECT_EQ(-22, FLAGS_test_int32);   // the -21 from the flagsfile didn't take
+}
+
+TEST(FlagsSetBeforeInitTest, TryFromEnv) {
+  EXPECT_EQ("pre-set", FLAGS_test_tryfromenv);
+}
+
+// The following test case verifies that ParseCommandLineFlags() and
+// ParseCommandLineNonHelpFlags() uses the last definition of a flag
+// in case it's defined more than once.
+
+DEFINE_int32(test_flag, -1, "used for testing gflags.cc");
+
+// Parses and returns the --test_flag flag.
+// If with_help is true, calls ParseCommandLineFlags; otherwise calls
+// ParseCommandLineNonHelpFlags.
+int32 ParseTestFlag(bool with_help, int argc, const char** const_argv) {
+  FlagSaver fs;  // Restores the flags before returning.
+
+  // Makes a copy of the input array s.t. it can be reused
+  // (ParseCommandLineFlags() will alter the array).
+  char** const argv_save = new char*[argc + 1];
+  char** argv = argv_save;
+  memcpy(argv, const_argv, sizeof(*argv)*(argc + 1));
+
+  if (with_help) {
+    ParseCommandLineFlags(&argc, &argv, true);
+  } else {
+    ParseCommandLineNonHelpFlags(&argc, &argv, true);
+  }
+
+  delete[] argv_save;
+  return FLAGS_test_flag;
+}
+
+TEST(ParseCommandLineFlagsUsesLastDefinitionTest,
+     WhenFlagIsDefinedTwiceOnCommandLine) {
+  const char* argv[] = {
+    "my_test",
+    "--test_flag=1",
+    "--test_flag=2",
+    NULL,
+  };
+
+  EXPECT_EQ(2, ParseTestFlag(true, arraysize(argv) - 1, argv));
+  EXPECT_EQ(2, ParseTestFlag(false, arraysize(argv) - 1, argv));
+}
+
+TEST(ParseCommandLineFlagsUsesLastDefinitionTest,
+     WhenFlagIsDefinedTwiceInFlagFile) {
+  const char* argv[] = {
+    "my_test",
+    GetFlagFileFlag(),
+    NULL,
+  };
+
+  EXPECT_EQ(2, ParseTestFlag(true, arraysize(argv) - 1, argv));
+  EXPECT_EQ(2, ParseTestFlag(false, arraysize(argv) - 1, argv));
+}
+
+TEST(ParseCommandLineFlagsUsesLastDefinitionTest,
+     WhenFlagIsDefinedInCommandLineAndThenFlagFile) {
+  const char* argv[] = {
+    "my_test",
+    "--test_flag=0",
+    GetFlagFileFlag(),
+    NULL,
+  };
+
+  EXPECT_EQ(2, ParseTestFlag(true, arraysize(argv) - 1, argv));
+  EXPECT_EQ(2, ParseTestFlag(false, arraysize(argv) - 1, argv));
+}
+
+TEST(ParseCommandLineFlagsUsesLastDefinitionTest,
+     WhenFlagIsDefinedInFlagFileAndThenCommandLine) {
+  const char* argv[] = {
+    "my_test",
+    GetFlagFileFlag(),
+    "--test_flag=3",
+    NULL,
+  };
+
+  EXPECT_EQ(3, ParseTestFlag(true, arraysize(argv) - 1, argv));
+  EXPECT_EQ(3, ParseTestFlag(false, arraysize(argv) - 1, argv));
+}
+
+TEST(ParseCommandLineFlagsUsesLastDefinitionTest,
+     WhenFlagIsDefinedInCommandLineAndFlagFileAndThenCommandLine) {
+  const char* argv[] = {
+    "my_test",
+    "--test_flag=0",
+    GetFlagFileFlag(),
+    "--test_flag=3",
+    NULL,
+  };
+
+  EXPECT_EQ(3, ParseTestFlag(true, arraysize(argv) - 1, argv));
+  EXPECT_EQ(3, ParseTestFlag(false, arraysize(argv) - 1, argv));
+}
+
+TEST(ParseCommandLineFlagsAndDashArgs, TwoDashArgFirst) {
+  const char* argv[] = {
+    "my_test",
+    "--",
+    "--test_flag=0",
+    NULL,
+  };
+
+  EXPECT_EQ(-1, ParseTestFlag(true, arraysize(argv) - 1, argv));
+  EXPECT_EQ(-1, ParseTestFlag(false, arraysize(argv) - 1, argv));
+}
+
+TEST(ParseCommandLineFlagsAndDashArgs, TwoDashArgMiddle) {
+  const char* argv[] = {
+    "my_test",
+    "--test_flag=7",
+    "--",
+    "--test_flag=0",
+    NULL,
+  };
+
+  EXPECT_EQ(7, ParseTestFlag(true, arraysize(argv) - 1, argv));
+  EXPECT_EQ(7, ParseTestFlag(false, arraysize(argv) - 1, argv));
+}
+
+TEST(ParseCommandLineFlagsAndDashArgs, OneDashArg) {
+  const char* argv[] = {
+    "my_test",
+    "-",
+    "--test_flag=0",
+    NULL,
+  };
+
+  EXPECT_EQ(0, ParseTestFlag(true, arraysize(argv) - 1, argv));
+  EXPECT_EQ(0, ParseTestFlag(false, arraysize(argv) - 1, argv));
+}
+
+#ifdef GTEST_HAS_DEATH_TEST
+TEST(ParseCommandLineFlagsUnknownFlagDeathTest,
+     FlagIsCompletelyUnknown) {
+  const char* argv[] = {
+    "my_test",
+    "--this_flag_does_not_exist",
+    NULL,
+  };
+
+  EXPECT_DEATH(ParseTestFlag(true, arraysize(argv) - 1, argv),
+               "unknown command line flag.*");
+  EXPECT_DEATH(ParseTestFlag(false, arraysize(argv) - 1, argv),
+               "unknown command line flag.*");
+}
+
+TEST(ParseCommandLineFlagsUnknownFlagDeathTest,
+     BoolFlagIsCompletelyUnknown) {
+  const char* argv[] = {
+    "my_test",
+    "--nothis_flag_does_not_exist",
+    NULL,
+  };
+
+  EXPECT_DEATH(ParseTestFlag(true, arraysize(argv) - 1, argv),
+               "unknown command line flag.*");
+  EXPECT_DEATH(ParseTestFlag(false, arraysize(argv) - 1, argv),
+               "unknown command line flag.*");
+}
+
+TEST(ParseCommandLineFlagsUnknownFlagDeathTest,
+     FlagIsNotABool) {
+  const char* argv[] = {
+    "my_test",
+    "--notest_string",
+    NULL,
+  };
+
+  EXPECT_DEATH(ParseTestFlag(true, arraysize(argv) - 1, argv),
+               "boolean value .* specified for .* command line flag");
+  EXPECT_DEATH(ParseTestFlag(false, arraysize(argv) - 1, argv),
+               "boolean value .* specified for .* command line flag");
+}
+#endif
+
+TEST(ParseCommandLineFlagsWrongFields,
+     DescriptionIsInvalid) {
+  // These must not be automatic variables, since command line flags
+  // aren't unregistered and gUnit uses FlagSaver to save and restore
+  // command line flags' values.  If these are on the stack, then when
+  // later tests attempt to save and restore their values, the stack
+  // addresses of these variables will be overwritten...  Stack smash!
+  static bool current_storage;
+  static bool defvalue_storage;
+  FlagRegisterer fr("flag_name", "bool", 0, "filename",
+                    &current_storage, &defvalue_storage);
+  CommandLineFlagInfo fi;
+  EXPECT_TRUE(GetCommandLineFlagInfo("flag_name", &fi));
+  EXPECT_EQ("", fi.description);
+  EXPECT_EQ(&current_storage, fi.flag_ptr);
+}
+
+static bool ValidateTestFlagIs5(const char* flagname, int32 flagval) {
+  if (flagval == 5)
+    return true;
+  printf("%s isn't 5!\n", flagname);
+  return false;
+}
+
+static bool ValidateTestFlagIs10(const char* flagname, int32 flagval) {
+  return flagval == 10;
+}
+
+
+TEST(FlagsValidator, ValidFlagViaArgv) {
+  const char* argv[] = {
+    "my_test",
+    "--test_flag=5",
+    NULL,
+  };
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+  EXPECT_EQ(5, ParseTestFlag(true, arraysize(argv) - 1, argv));
+  // Undo the flag validator setting
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, NULL));
+}
+
+TEST(FlagsValidator, ValidFlagViaSetDefault) {
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+  // SetCommandLineOptionWithMode returns the empty string on error.
+  EXPECT_NE("", SetCommandLineOptionWithMode("test_flag", "5",
+                                             SET_FLAG_IF_DEFAULT));
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, NULL));
+}
+
+TEST(FlagsValidator, ValidFlagViaSetValue) {
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+  FLAGS_test_flag = 100;   // doesn't trigger the validator
+  // SetCommandLineOptionWithMode returns the empty string on error.
+  EXPECT_NE("", SetCommandLineOptionWithMode("test_flag", "5",
+                                             SET_FLAGS_VALUE));
+  EXPECT_NE("", SetCommandLineOptionWithMode("test_flag", "5",
+                                             SET_FLAGS_DEFAULT));
+  EXPECT_NE("", SetCommandLineOption("test_flag", "5"));
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, NULL));
+}
+
+#ifdef GTEST_HAS_DEATH_TEST
+TEST(FlagsValidatorDeathTest, InvalidFlagViaArgv) {
+  const char* argv[] = {
+    "my_test",
+    "--test_flag=50",
+    NULL,
+  };
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+  EXPECT_DEATH(ParseTestFlag(true, arraysize(argv) - 1, argv),
+               "ERROR: failed validation of new value '50' for flag 'test_flag'");
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, NULL));
+}
+#endif
+
+TEST(FlagsValidator, InvalidFlagViaSetDefault) {
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+  // SetCommandLineOptionWithMode returns the empty string on error.
+  EXPECT_EQ("", SetCommandLineOptionWithMode("test_flag", "50",
+                                             SET_FLAG_IF_DEFAULT));
+  EXPECT_EQ(-1, FLAGS_test_flag);   // the setting-to-50 should have failed
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, NULL));
+}
+
+TEST(FlagsValidator, InvalidFlagViaSetValue) {
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+  FLAGS_test_flag = 100;   // doesn't trigger the validator
+  // SetCommandLineOptionWithMode returns the empty string on error.
+  EXPECT_EQ("", SetCommandLineOptionWithMode("test_flag", "50",
+                                             SET_FLAGS_VALUE));
+  EXPECT_EQ("", SetCommandLineOptionWithMode("test_flag", "50",
+                                             SET_FLAGS_DEFAULT));
+  EXPECT_EQ("", SetCommandLineOption("test_flag", "50"));
+  EXPECT_EQ(100, FLAGS_test_flag);   // the setting-to-50 should have failed
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, NULL));
+}
+
+#ifdef GTEST_HAS_DEATH_TEST
+TEST(FlagsValidatorDeathTest, InvalidFlagNeverSet) {
+  // If a flag keeps its default value, and that default value is
+  // invalid, we should die at argv-parse time.
+  const char* argv[] = {
+    "my_test",
+    NULL,
+  };
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+  EXPECT_DEATH(ParseTestFlag(true, arraysize(argv) - 1, argv),
+               "ERROR: --test_flag must be set on the commandline");
+}
+#endif
+
+TEST(FlagsValidator, InvalidFlagPtr) {
+  int32 dummy;
+  EXPECT_FALSE(RegisterFlagValidator(NULL, &ValidateTestFlagIs5));
+  EXPECT_FALSE(RegisterFlagValidator(&dummy, &ValidateTestFlagIs5));
+}
+
+TEST(FlagsValidator, RegisterValidatorTwice) {
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+  EXPECT_FALSE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs10));
+  EXPECT_FALSE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs10));
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, NULL));
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs10));
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, NULL));
+}
+
+TEST(FlagsValidator, CommandLineFlagInfo) {
+  CommandLineFlagInfo info;
+  info = GetCommandLineFlagInfoOrDie("test_flag");
+  EXPECT_FALSE(info.has_validator_fn);
+
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+  info = GetCommandLineFlagInfoOrDie("test_flag");
+  EXPECT_TRUE(info.has_validator_fn);
+
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, NULL));
+  info = GetCommandLineFlagInfoOrDie("test_flag");
+  EXPECT_FALSE(info.has_validator_fn);
+}
+
+TEST(FlagsValidator, FlagSaver) {
+  {
+    FlagSaver fs;
+    EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+    EXPECT_EQ("", SetCommandLineOption("test_flag", "50"));  // fails validation
+  }
+  EXPECT_NE("", SetCommandLineOption("test_flag", "50"));  // validator is gone
+
+  EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, &ValidateTestFlagIs5));
+  {
+    FlagSaver fs;
+    EXPECT_TRUE(RegisterFlagValidator(&FLAGS_test_flag, NULL));
+    EXPECT_NE("", SetCommandLineOption("test_flag", "50"));  // no validator
+  }
+  EXPECT_EQ("", SetCommandLineOption("test_flag", "50"));  // validator is back
+}
+
+
+}  // unnamed namespace
+
+int main(int argc, char **argv) {
+
+  // Run unit tests only if called without arguments, otherwise this program
+  // is used by an "external" usage test
+  const bool run_tests = (argc == 1);
+
+  // We need to call SetArgv before parsing flags, so our "test" argv will
+  // win out over this executable's real argv.  That makes running this
+  // test with a real --help flag kinda annoying, unfortunately.
+  const char* test_argv[] = { "/test/argv/for/gflags_unittest",
+                              "argv 2", "3rd argv", "argv #4" };
+  SetArgv(arraysize(test_argv), test_argv);
+
+  // The first arg is the usage message, also important for testing.
+  string usage_message = (string(GetArgv0()) +
+                          ": <useless flag> [...]\nDoes something useless.\n");
+
+  // We test setting tryfromenv manually, and making sure
+  // ParseCommandLineFlags still evaluates it.
+  FLAGS_tryfromenv = "test_tryfromenv";
+  setenv("FLAGS_test_tryfromenv", "pre-set", 1);
+
+  // Modify flag values from declared default value in two ways.
+  // The recommended way:
+  SetCommandLineOptionWithMode("changed_bool1", "true", SET_FLAGS_DEFAULT);
+
+  // The non-recommended way:
+  FLAGS_changed_bool2 = true;
+
+  SetUsageMessage(usage_message.c_str());
+  SetVersionString("test_version");
+  ParseCommandLineFlags(&argc, &argv, true);
+  MakeTmpdir(&FLAGS_test_tmpdir);
+
+  int exit_status = 0;
+  if (run_tests) {
+	  fprintf(stdout, "Running the unit tests now...\n\n"); fflush(stdout);
+	  exit_status = RUN_ALL_TESTS();
+  } else fprintf(stderr, "\n\nPASS\n");
+  ShutDownCommandLineFlags();
+  return exit_status;
+}
+
+} // GFLAGS_NAMESPACE
+
+int main(int argc, char** argv) {
+  return GFLAGS_NAMESPACE::main(argc, argv);
+}
+