1# Quickstart: Building with Bazel 2 3This tutorial aims to get you up and running with GoogleTest using the Bazel 4build system. If you're using GoogleTest for the first time or need a refresher, 5we recommend this tutorial as a starting point. 6 7## Prerequisites 8 9To complete this tutorial, you'll need: 10 11* A compatible operating system (e.g. Linux, macOS, Windows). 12* A compatible C++ compiler that supports at least C++11. 13* [Bazel](https://bazel.build/), the preferred build system used by the 14 GoogleTest team. 15 16See [Supported Platforms](platforms.md) for more information about platforms 17compatible with GoogleTest. 18 19If you don't already have Bazel installed, see the 20[Bazel installation guide](https://docs.bazel.build/versions/master/install.html). 21 22{: .callout .note} 23Note: The terminal commands in this tutorial show a Unix shell prompt, but the 24commands work on the Windows command line as well. 25 26## Set up a Bazel workspace 27 28A 29[Bazel workspace](https://docs.bazel.build/versions/master/build-ref.html#workspace) 30is a directory on your filesystem that you use to manage source files for the 31software you want to build. Each workspace directory has a text file named 32`WORKSPACE` which may be empty, or may contain references to external 33dependencies required to build the outputs. 34 35First, create a directory for your workspace: 36 37``` 38$ mkdir my_workspace && cd my_workspace 39``` 40 41Next, you’ll create the `WORKSPACE` file to specify dependencies. A common and 42recommended way to depend on GoogleTest is to use a 43[Bazel external dependency](https://docs.bazel.build/versions/master/external.html) 44via the 45[`http_archive` rule](https://docs.bazel.build/versions/master/repo/http.html#http_archive). 46To do this, in the root directory of your workspace (`my_workspace/`), create a 47file named `WORKSPACE` with the following contents: 48 49``` 50load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive") 51 52http_archive( 53 name = "com_google_googletest", 54 urls = ["https://github.com/google/googletest/archive/609281088cfefc76f9d0ce82e1ff6c30cc3591e5.zip"], 55 strip_prefix = "googletest-609281088cfefc76f9d0ce82e1ff6c30cc3591e5", 56) 57``` 58 59The above configuration declares a dependency on GoogleTest which is downloaded 60as a ZIP archive from GitHub. In the above example, 61`609281088cfefc76f9d0ce82e1ff6c30cc3591e5` is the Git commit hash of the 62GoogleTest version to use; we recommend updating the hash often to point to the 63latest version. 64 65Bazel also needs a dependency on the 66[`rules_cc` repository](https://github.com/bazelbuild/rules_cc) to build C++ 67code, so add the following to the `WORKSPACE` file: 68 69``` 70http_archive( 71 name = "rules_cc", 72 urls = ["https://github.com/bazelbuild/rules_cc/archive/40548a2974f1aea06215272d9c2b47a14a24e556.zip"], 73 strip_prefix = "rules_cc-40548a2974f1aea06215272d9c2b47a14a24e556", 74) 75``` 76 77Now you're ready to build C++ code that uses GoogleTest. 78 79## Create and run a binary 80 81With your Bazel workspace set up, you can now use GoogleTest code within your 82own project. 83 84As an example, create a file named `hello_test.cc` in your `my_workspace` 85directory with the following contents: 86 87```cpp 88#include <gtest/gtest.h> 89 90// Demonstrate some basic assertions. 91TEST(HelloTest, BasicAssertions) { 92 // Expect two strings not to be equal. 93 EXPECT_STRNE("hello", "world"); 94 // Expect equality. 95 EXPECT_EQ(7 * 6, 42); 96} 97``` 98 99GoogleTest provides [assertions](primer.md#assertions) that you use to test the 100behavior of your code. The above sample includes the main GoogleTest header file 101and demonstrates some basic assertions. 102 103To build the code, create a file named `BUILD` in the same directory with the 104following contents: 105 106``` 107load("@rules_cc//cc:defs.bzl", "cc_test") 108 109cc_test( 110 name = "hello_test", 111 size = "small", 112 srcs = ["hello_test.cc"], 113 deps = ["@com_google_googletest//:gtest_main"], 114) 115``` 116 117This `cc_test` rule declares the C++ test binary you want to build, and links to 118GoogleTest (`//:gtest_main`) using the prefix you specified in the `WORKSPACE` 119file (`@com_google_googletest`). For more information about Bazel `BUILD` files, 120see the 121[Bazel C++ Tutorial](https://docs.bazel.build/versions/master/tutorial/cpp.html). 122 123Now you can build and run your test: 124 125<pre> 126<strong>my_workspace$ bazel test --test_output=all //:hello_test</strong> 127INFO: Analyzed target //:hello_test (26 packages loaded, 362 targets configured). 128INFO: Found 1 test target... 129INFO: From Testing //:hello_test: 130==================== Test output for //:hello_test: 131Running main() from gmock_main.cc 132[==========] Running 1 test from 1 test suite. 133[----------] Global test environment set-up. 134[----------] 1 test from HelloTest 135[ RUN ] HelloTest.BasicAssertions 136[ OK ] HelloTest.BasicAssertions (0 ms) 137[----------] 1 test from HelloTest (0 ms total) 138 139[----------] Global test environment tear-down 140[==========] 1 test from 1 test suite ran. (0 ms total) 141[ PASSED ] 1 test. 142================================================================================ 143Target //:hello_test up-to-date: 144 bazel-bin/hello_test 145INFO: Elapsed time: 4.190s, Critical Path: 3.05s 146INFO: 27 processes: 8 internal, 19 linux-sandbox. 147INFO: Build completed successfully, 27 total actions 148//:hello_test PASSED in 0.1s 149 150INFO: Build completed successfully, 27 total actions 151</pre> 152 153Congratulations! You've successfully built and run a test binary using 154GoogleTest. 155 156## Next steps 157 158* [Check out the Primer](primer.md) to start learning how to write simple 159 tests. 160* [See the code samples](samples.md) for more examples showing how to use a 161 variety of GoogleTest features. 162