Google C++ Testing Framework

https://github.com/google/googletest

Overview

Google's framework for writing C++ tests on a variety of platforms (Linux, Mac OS X, Windows, Windows CE, Symbian, etc). Based on the xUnit architecture. Supports automatic test discovery, a rich set of assertions, user-defined assertions, death tests, fatal and non-fatal failures, various options for running the tests, and XML test report generation.

Please see the project page above for more information as well as the mailing list for questions, discussions, and development. There is also an IRC channel on OFTC (irc.oftc.net) #gtest available. Please join us!

Requirements for End Users

Google Test is designed to have fairly minimal requirements to build and use with your projects, but there are some. Currently, we support Linux, Windows, Mac OS X, and Cygwin. We will also make our best effort to support other platforms (e.g. Solaris, AIX, and z/OS). However, since core members of the Google Test project have no access to these platforms, Google Test may have outstanding issues there. If you notice any problems on your platform, please notify googletestframework@googlegroups.com. Patches for fixing them are even more welcome!

Linux Requirements

These are the base requirements to build and use Google Test from a source package (as described below):

• GNU-compatible Make or gmake
• POSIX-standard shell
• POSIX(-2) Regular Expressions (regex.h)
• A C++98-standard-compliant compiler

Windows Requirements

• Microsoft Visual C++ 7.1 or newer

Cygwin Requirements

• Cygwin 1.5.25-14 or newer

Mac OS X Requirements

• Mac OS X 10.4 Tiger or newer
• Developer Tools Installed

Also, you'll need [CMake](http://www.cmake.org/ CMake) 2.6.4 or higher if you want to build the samples using the provided CMake script, regardless of the platform.

Requirements for Contributors

We welcome patches. If you plan to contribute a patch, you need to build Google Test and its own tests from a git checkout (described below), which has further requirements:

• Python version 2.3 or newer (for running some of the tests and re-generating certain source files from templates)
• CMake 2.6.4 or newer

Getting the Source

Google Test's source is available from its GitHub repository at https://github.com/google/googletest. The GitHub repository offers stable tagged releases available as .ZIP archives. A Git checkout requires a few extra steps and some extra software packages on your system, but lets you track the latest development and make patches much more easily, so we highly encourage it.

Source Package

Snapshots of Google Test's master branch can be downloaded directly with GitHub's "Download ZIP" button on the main page.

Versioned releases are also available by clicking on Releases in the project page.

Git Checkout

To check out the master branch of Google Test, run the following git command:

git clone https://github.com/google/googletest.git (via HTTPS)

Setting up the Build

To build Google Test and your tests that use it, you need to tell your build system where to find its headers and source files. The exact way to do it depends on which build system you use, and is usually straightforward.

Generic Build Instructions

Suppose you put Google Test in directory ${GTEST_DIR}. To build it, create a library build target (or a project as called by Visual Studio and Xcode) to compile

${GTEST_DIR}/src/gtest-all.cc

with ${GTEST_DIR}/include in the system header search path and ${GTEST_DIR} in the normal header search path. Assuming a Linux-like system and gcc, something like the following will do:

g++ -isystem ${GTEST_DIR}/include -I${GTEST_DIR} \
    -pthread -c ${GTEST_DIR}/src/gtest-all.cc
ar -rv libgtest.a gtest-all.o

(We need -pthread as Google Test uses threads.)

Next, you should compile your test source file with ${GTEST_DIR}/include in the system header search path, and link it with gtest and any other necessary libraries:

g++ -isystem ${GTEST_DIR}/include -pthread path/to/your_test.cc libgtest.a \
    -o your_test

As an example, the make/ directory contains a Makefile that you can use to build Google Test on systems where GNU make is available (e.g. Linux, Mac OS X, and Cygwin). It doesn't try to build Google Test's own tests. Instead, it just builds the Google Test library and a sample test. You can use it as a starting point for your own build script.

If the default settings are correct for your environment, the following commands should succeed:

cd ${GTEST_DIR}/make
make
./sample1_unittest

If you see errors, try to tweak the contents of make/Makefile to make them go away. There are instructions in make/Makefile on how to do it.

Using CMake

Google Test comes with a CMake build script ( CMakeLists.txt) that can be used on a wide range of platforms ("C" stands for cross-platform.). If you don't have CMake installed already, you can download it for free from http://www.cmake.org/.

CMake works by generating native makefiles or build projects that can be used in the compiler environment of your choice. The typical workflow starts with:

mkdir mybuild       # Create a directory to hold the build output.
cd mybuild
cmake ${GTEST_DIR}  # Generate native build scripts.

If you want to build Google Test's samples, you should replace the last command with

cmake -Dgtest_build_samples=ON ${GTEST_DIR}

If you are on a *nix system, you should now see a Makefile in the current directory. Just type 'make' to build gtest.

If you use Windows and have Visual Studio installed, a gtest.sln file and several .vcproj files will be created. You can then build them using Visual Studio.

On Mac OS X with Xcode installed, a .xcodeproj file will be generated.

Legacy Build Scripts

Before settling on CMake, we have been providing hand-maintained build projects/scripts for Visual Studio, Xcode, and Autotools. While we continue to provide them for convenience, they are not actively maintained any more. We highly recommend that you follow the instructions in the previous two sections to integrate Google Test with your existing build system.

If you still need to use the legacy build scripts, here's how:

The msvc\ folder contains two solutions with Visual C++ projects. Open the gtest.sln or gtest-md.sln file using Visual Studio, and you are ready to build Google Test the same way you build any Visual Studio project. Files that have names ending with -md use DLL versions of Microsoft runtime libraries (the /MD or the /MDd compiler option). Files without that suffix use static versions of the runtime libraries (the /MT or the /MTd option). Please note that one must use the same option to compile both gtest and the test code. If you use Visual Studio 2005 or above, we recommend the -md version as /MD is the default for new projects in these versions of Visual Studio.

On Mac OS X, open the gtest.xcodeproj in the xcode/ folder using Xcode. Build the "gtest" target. The universal binary framework will end up in your selected build directory (selected in the Xcode "Preferences..." -> "Building" pane and defaults to xcode/build). Alternatively, at the command line, enter:

xcodebuild

This will build the "Release" configuration of gtest.framework in your default build location. See the "xcodebuild" man page for more information about building different configurations and building in different locations.

If you wish to use the Google Test Xcode project with Xcode 4.x and above, you need to either:

• update the SDK configuration options in xcode/Config/General.xconfig. Comment options SDKROOT, MACOS_DEPLOYMENT_TARGET, and GCC_VERSION. If you choose this route you lose the ability to target earlier versions of MacOS X.
• Install an SDK for an earlier version. This doesn't appear to be supported by Apple, but has been reported to work (http://stackoverflow.com/questions/5378518).

Tweaking Google Test

Google Test can be used in diverse environments. The default configuration may not work (or may not work well) out of the box in some environments. However, you can easily tweak Google Test by defining control macros on the compiler command line. Generally, these macros are named like GTEST_XYZ and you define them to either 1 or 0 to enable or disable a certain feature.

We list the most frequently used macros below. For a complete list, see file include/gtest/internal/gtest-port.h.

Choosing a TR1 Tuple Library

Some Google Test features require the C++ Technical Report 1 (TR1) tuple library, which is not yet available with all compilers. The good news is that Google Test implements a subset of TR1 tuple that's enough for its own need, and will automatically use this when the compiler doesn't provide TR1 tuple.

Usually you don't need to care about which tuple library Google Test uses. However, if your project already uses TR1 tuple, you need to tell Google Test to use the same TR1 tuple library the rest of your project uses, or the two tuple implementations will clash. To do that, add

-DGTEST_USE_OWN_TR1_TUPLE=0

to the compiler flags while compiling Google Test and your tests. If you want to force Google Test to use its own tuple library, just add

-DGTEST_USE_OWN_TR1_TUPLE=1

to the compiler flags instead.

If you don't want Google Test to use tuple at all, add

-DGTEST_HAS_TR1_TUPLE=0

and all features using tuple will be disabled.

Multi-threaded Tests

Google Test is thread-safe where the pthread library is available. After #include "gtest/gtest.h", you can check the GTEST_IS_THREADSAFE macro to see whether this is the case (yes if the macro is #defined to 1, no if it's undefined.).

If Google Test doesn't correctly detect whether pthread is available in your environment, you can force it with

-DGTEST_HAS_PTHREAD=1

or

-DGTEST_HAS_PTHREAD=0

When Google Test uses pthread, you may need to add flags to your compiler and/or linker to select the pthread library, or you'll get link errors. If you use the CMake script or the deprecated Autotools script, this is taken care of for you. If you use your own build script, you'll need to read your compiler and linker's manual to figure out what flags to add.

As a Shared Library (DLL)

Google Test is compact, so most users can build and link it as a static library for the simplicity. You can choose to use Google Test as a shared library (known as a DLL on Windows) if you prefer.

To compile gtest as a shared library, add

-DGTEST_CREATE_SHARED_LIBRARY=1

to the compiler flags. You'll also need to tell the linker to produce a shared library instead - consult your linker's manual for how to do it.

To compile your tests that use the gtest shared library, add

-DGTEST_LINKED_AS_SHARED_LIBRARY=1

to the compiler flags.

Note: while the above steps aren't technically necessary today when using some compilers (e.g. GCC), they may become necessary in the future, if we decide to improve the speed of loading the library (see http://gcc.gnu.org/wiki/Visibility for details). Therefore you are recommended to always add the above flags when using Google Test as a shared library. Otherwise a future release of Google Test may break your build script.

Avoiding Macro Name Clashes

In C++, macros don't obey namespaces. Therefore two libraries that both define a macro of the same name will clash if you #include both definitions. In case a Google Test macro clashes with another library, you can force Google Test to rename its macro to avoid the conflict.

Specifically, if both Google Test and some other code define macro FOO, you can add

-DGTEST_DONT_DEFINE_FOO=1

to the compiler flags to tell Google Test to change the macro's name from FOO to GTEST_FOO. Currently FOO can be FAIL, SUCCEED, or TEST. For example, with -DGTEST_DONT_DEFINE_TEST=1, you'll need to write

GTEST_TEST(SomeTest, DoesThis) { ... }

instead of

TEST(SomeTest, DoesThis) { ... }

in order to define a test.

Upgrating from an Earlier Version

We strive to keep Google Test releases backward compatible. Sometimes, though, we have to make some breaking changes for the users' long-term benefits. This section describes what you'll need to do if you are upgrading from an earlier version of Google Test.

Upgrading from 1.3.0 or Earlier

You may need to explicitly enable or disable Google Test's own TR1 tuple library. See the instructions in section "Choosing a TR1 Tuple Library".

Upgrading from 1.4.0 or Earlier

The Autotools build script (configure + make) is no longer officially supportted. You are encouraged to migrate to your own build system or use CMake. If you still need to use Autotools, you can find instructions in the README file from Google Test 1.4.0.

On platforms where the pthread library is available, Google Test uses it in order to be thread-safe. See the "Multi-threaded Tests" section for what this means to your build script.

If you use Microsoft Visual C++ 7.1 with exceptions disabled, Google Test will no longer compile. This should affect very few people, as a large portion of STL (including ) doesn't compile in this mode anyway. We decided to stop supporting it in order to greatly simplify Google Test's implementation.

Developing Google Test

This section discusses how to make your own changes to Google Test.

Testing Google Test Itself

To make sure your changes work as intended and don't break existing functionality, you'll want to compile and run Google Test's own tests. For that you can use CMake:

mkdir mybuild
cd mybuild
cmake -Dgtest_build_tests=ON ${GTEST_DIR}

Make sure you have Python installed, as some of Google Test's tests are written in Python. If the cmake command complains about not being able to find Python (Could NOT find PythonInterp (missing: PYTHON_EXECUTABLE)), try telling it explicitly where your Python executable can be found:

cmake -DPYTHON_EXECUTABLE=path/to/python -Dgtest_build_tests=ON ${GTEST_DIR}

Next, you can build Google Test and all of its own tests. On *nix, this is usually done by 'make'. To run the tests, do

make test

All tests should pass.

Regenerating Source Files

Some of Google Test's source files are generated from templates (not in the C++ sense) using a script. A template file is named FOO.pump, where FOO is the name of the file it will generate. For example, the file include/gtest/internal/gtest-type-util.h.pump is used to generate gtest-type-util.h in the same directory.

Normally you don't need to worry about regenerating the source files, unless you need to modify them. In that case, you should modify the corresponding .pump files instead and run the pump.py Python script to regenerate them. You can find pump.py in the scripts/ directory. Read the Pump manual for how to use it.

Contributing a Patch

We welcome patches. Please read the Google Test developer's guide for how you can contribute. In particular, make sure you have signed the Contributor License Agreement, or we won't be able to accept the patch.

Happy testing!