GoogleTest hello world.

./build and ./test work automatically when cwd is inside userland/libs/XXX
without --package-all.

Author: cirosantilli

.gitmodules

@@ -11,6 +11,9 @@
 [submodule "submodules/crosstool-ng"]
 	path = submodules/crosstool-ng
 	url = https://github.com/cirosantilli/crosstool-ng
+[submodule "submodules/freebsd"]
+	path = submodules/freebsd
+	url = https://github.com/cirosantilli/freebsd
 [submodule "submodules/gcc"]
 	path = submodules/gcc
 	url = https://github.com/cirosantilli/gcc
@@ -30,6 +33,9 @@
 # git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
 # But git clone --branch --depth 1 worked weirdly:
 # https://unix.stackexchange.com/questions/338578/linux-kernel-source-code-size-difference
+[submodule "submodules/googletest"]
+	path = submodules/googletest
+	url = https://github.com/cirosantilli/googletest
 [submodule "submodules/linux"]
 	path = submodules/linux
 	url = https://github.com/cirosantilli/linux
@@ -39,6 +45,3 @@
 [submodule "submodules/xen"]
 	path = submodules/xen
 	url = https://github.com/cirosantilli/xen
-[submodule "submodules/freebsd"]
-	path = submodules/freebsd
-	url = https://github.com/cirosantilli/freebsd

README.adoc

@@ -13504,7 +13504,7 @@ Running individual unit tests is not yet exposed, but it is easy to do: while ru
 
 so you can just copy paste the command.
 
-Building individual tests is possible with:
+Building individual tests is possible with `--unit-test` (singular, no 's'):
 
 ....
 ./build-gem5 --unit-test base/circlebuf.test
@@ -20628,6 +20628,62 @@ link:userland/cpp/custom_iterator.cpp[]: there is no way to easily define a nice
 * https://stackoverflow.com/questions/3582608/how-to-correctly-implement-custom-iterators-and-const-iterators
 * https://stackoverflow.com/questions/6471019/can-should-i-inherit-from-an-stl-iterator
 
+[[cpp-third-party-libraries]]
+==== C++ third-party libraries
+
+Under: <<userland-libs-directory>>.
+
+===== Boost
+
+link:https://++en.wikipedia.org/wiki/Boost_(C%2B%2B_libraries)++[]
+
+link:userland/libs/boost[]:
+
+* link:userland/libs/boost/bimap.cpp[]
+
+===== GoogleTest
+
+https://github.com/google/googletest
+
+On Ubuntu 20.04, the package:
+
+....
+sudo apt install googletest
+....
+
+does not contain prebuilts, and it is intentional, it is incomprehensible:
+
+* https://askubuntu.com/questions/97626/how-to-install-googletest/1295185#1295185
+* https://askubuntu.com/questions/145887/why-no-library-files-installed-for-google-test
+
+so you might as well just `git clone` and build the damned thing yourself:
+
+....
+git submodule update --init submodules/googletest
+cd submodules/googletest
+mkdir build
+cd build
+cmake ..
+make -j`nproc`
+cd ../../userland/libs/googletest
+./build
+....
+
+link:userland/libs/googletest[]:
+
+* userland/libs/googletest/main.cpp[]
+
+===== HDF5
+
+https://en.wikipedia.org/wiki/Hierarchical_Data_Format
+
+Binary format to store data. TODO vs databases, notably SQLite: https://datascience.stackexchange.com/questions/262/hierarchical-data-format-what-are-the-advantages-compared-to-alternative-format
+
+Examples:
+
+* link:userland/libs/hdf5[]
+* gem5 can dump statistics as HDF5: <<gem5-hdf5-statistics>>
+
 === POSIX
 
 Programs under link:userland/posix/[] are examples of POSIX C programming.
@@ -21344,24 +21400,19 @@ See for example <<blas>>. Since it is located under `userland/libs/openblas`, it
 ./build-userland --package-all
 ....
 
-==== Boost
-
-link:https://++en.wikipedia.org/wiki/Boost_(C%2B%2B_libraries)++[]
-
-link:userland/libs/boost[]
+As an exception, if you first `cd` directly into one of the directories and do a <<userland-setup-getting-started-natively,native host build>>, e.g.:
 
-* link:userland/libs/boost/bimap.cpp[]
-
-==== HDF5
-
-https://en.wikipedia.org/wiki/Hierarchical_Data_Format
+....
+sudo apt install libeigen3-dev
+cd userland/libs/eigen
+./build
+....
 
-Binary format to store data. TODO vs databases, notably SQLite: https://datascience.stackexchange.com/questions/262/hierarchical-data-format-what-are-the-advantages-compared-to-alternative-format
+then that library will be automatically enabled.
 
-Examples:
+See also:
 
-* link:userland/libs/hdf5[]
-* gem5 can dump statistics as HDF5: <<gem5-hdf5-statistics>>
+* <<cpp-third-party-libraries>>
 
 === Userland content filename conventions
 

build-userland-in-tree

@@ -10,16 +10,19 @@ build_userland = lkmc.import_path.import_path_relative_root('build-userland')
 
 class Main(build_userland.Main):
     def __init__(self):
+        defaults = {
+            'archs': [platform.processor()],
+            'gcc_which': 'host',
+            'in_tree': True,
+            'targets': ['.'],
+        }
+        if self.cwd_in_lib():
+            defaults['package_all'] = True
         super().__init__(
             description='''\
 https://cirosantilli.com/linux-kernel-module-cheat#userland-setup-getting-started-natively
 ''',
-            defaults={
-                'archs': [platform.processor()],
-                'gcc_which': 'host',
-                'in_tree': True,
-                'targets': ['.'],
-            }
+            defaults=defaults
         )
 
 if __name__ == '__main__':

common.py

@@ -69,6 +69,8 @@
 consts['kernel_modules_source_dir'] = os.path.join(consts['root_dir'], consts['kernel_modules_subdir'])
 consts['userland_subdir'] = 'userland'
 consts['userland_source_dir'] = os.path.join(consts['root_dir'], consts['userland_subdir'])
+consts['userland_libs_basename'] = 'libs'
+consts['userland_source_libs_dir'] = os.path.join(consts['userland_source_dir'], consts['userland_libs_basename'])
 consts['userland_source_arch_dir'] = os.path.join(consts['userland_source_dir'], 'arch')
 consts['userland_executable_ext'] = '.out'
 consts['baremetal_executable_ext'] = '.elf'
@@ -83,6 +85,7 @@
 consts['linux_source_dir'] = os.path.join(consts['submodules_dir'], 'linux')
 consts['linux_config_dir'] = os.path.join(consts['root_dir'], 'linux_config')
 consts['gem5_default_source_dir'] = os.path.join(consts['submodules_dir'], 'gem5')
+consts['googletest_source_dir'] = os.path.join(consts['submodules_dir'], 'googletest')
 consts['rootfs_overlay_dir'] = os.path.join(consts['root_dir'], 'rootfs_overlay')
 consts['extract_vmlinux'] = os.path.join(consts['linux_source_dir'], 'scripts', 'extract-vmlinux')
 consts['qemu_source_dir'] = os.path.join(consts['submodules_dir'], 'qemu')
@@ -1358,6 +1361,10 @@ def get_gem5_target_path(env, name):
         '''
         return os.path.join(env['gem5_executable_dir'], name + env['gem5_executable_suffix'])
 
+    @staticmethod
+    def cwd_in_lib():
+        return pathlib.Path(common.consts['userland_source_libs_dir']) in pathlib.Path(os.getcwd()).parents
+
     def gem5_list_checkpoint_dirs(self):
         '''
         List checkpoint directory, oldest first.
@@ -1896,14 +1903,15 @@ def _build_one(
                             '-march={}'.format(self.env['march']), LF,
                         ])
                 if dirpath_relative_root_components_len > 0:
-                    if dirpath_relative_root_components[0] == 'userland':
+                    if dirpath_relative_root_components[0] == consts['userland_subdir']:
                         if dirpath_relative_root_components_len > 1:
-                            if dirpath_relative_root_components[1] == 'libs':
+                            if dirpath_relative_root_components[1] == self.env['userland_libs_basename']:
                                 if dirpath_relative_root_components_len > 1:
                                     if self.env['gcc_which'] == 'host':
                                         eigen_root = '/'
                                     else:
                                         eigen_root = self.env['buildroot_staging_dir']
+                                    # TODO move to path_properties.py somehow.
                                     packages = {
                                         'boost': {
                                             # Header only, no pkg-config package.
@@ -1931,6 +1939,17 @@ def _build_one(
                                         'hdf5': {
                                             'pkg_config_id': 'hdf5-serial',
                                         },
+                                        'googletest': {
+                                            'cc_flags': [
+                                                '-I', os.path.join(self.env['googletest_source_dir'], 'googletest', 'include'), LF,
+                                                '-I', os.path.join(self.env['googletest_source_dir'], 'googlemock', 'include'), LF,
+                                            ],
+                                            'cc_flags_after': [
+                                                os.path.join(self.env['googletest_source_dir'], 'build', 'lib', 'libgtest.a'), LF,
+                                                os.path.join(self.env['googletest_source_dir'], 'build', 'lib', 'libgtest_main.a'), LF,
+                                                os.path.join(self.env['googletest_source_dir'], 'build', 'lib', 'libgmock.a'), LF,
+                                            ],
+                                        },
                                     }
                                     package_key = dirpath_relative_root_components[2]
                                     if package_key in packages:
@@ -1951,7 +1970,7 @@ def _build_one(
                                         ]).decode()
                                         cc_flags.extend(self.sh.shlex_split(pkg_config_output))
                                     if 'cc_flags_after' in package:
-                                        cc_flags.extend(package['cc_flags_after'])
+                                        cc_flags_after.extend(package['cc_flags_after'])
                                     else:
                                         pkg_config_output = subprocess.check_output([
                                             self.env['pkg_config'],

path_properties.py

@@ -749,6 +749,12 @@ def get(path):
                     {'requires_dynamic_library': True},
                     {
                         'cython': {'no_build': True},
+                        'googletest': (
+                            {},
+                            {
+                                'fail.cpp': {'exit_status': 1},
+                            }
+                        ),
                         'libdrm': {'requires_sudo': True},
                         'hdf5': (
                             {},

submodules/googletest

@@ -6,15 +6,18 @@ test_user_mode = lkmc.import_path.import_path_relative_root('test-executables')
 
 class Main(test_user_mode.Main):
     def __init__(self):
+        defaults = {
+            'emulators': ['native'],
+            'in_tree': True,
+            'tests': ['.'],
+        }
+        if self.cwd_in_lib():
+            defaults['package_all'] = True
         super().__init__(
             description='''\
 https://cirosantilli.com/linux-kernel-module-cheat#userland-setup-getting-started-natively
 ''',
-            defaults={
-                'emulators': ['native'],
-                'in_tree': True,
-                'tests': ['.'],
-            }
+            defaults=defaults
         )
 
 if __name__ == '__main__':

test-executables-in-tree

@@ -0,0 +1 @@
+../build

userland/libs/googletest/build

@@ -0,0 +1,9 @@
+#include <gtest/gtest.h>
+
+TEST(FailTest, ThisTestPasses) {
+  EXPECT_EQ(1, 1);
+}
+
+TEST(FailTest, ThisTestFails) {
+  EXPECT_EQ(1, 2);
+}

userland/libs/googletest/fail.cpp

@@ -0,0 +1,27 @@
+#include <utility>
+#include <vector>
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+using testing::ElementsAre;
+using testing::Pair;
+
+TEST(MainTest, MyTest0) {
+    EXPECT_EQ(1, 1);
+
+    // Array comparison.
+    // https://stackoverflow.com/questions/1460703/comparison-of-arrays-in-google-test
+    ASSERT_THAT(
+        (std::vector<int>{5, 10, 15}),
+        ElementsAre(5, 10, 15)
+    );
+    ASSERT_THAT(
+        (std::vector<std::pair<int, int>>{{1, -1}, {2, -2}}),
+        ElementsAre(Pair(1, -1), Pair(2, -2))
+    );
+}
+
+TEST(MainTest, MyTest1) {
+    EXPECT_EQ(1, 1);
+}