[DO-972][DO-980] add freetype and pkgconf recipes (!6)

Co-authored-by: aleksandr.vodyanov <aleksandr.vodyanov@avroid.tech>
Reviewed-on: https://git.avroid.tech/Conan/conan_build/pulls/6

recipes/pkgconf/all/test_package/conanfile.py

@@ -0,0 +1,83 @@
+from io import StringIO
+import os
+from pathlib import Path
+import re
+
+from conan import ConanFile
+from conan.tools.build import can_run
+from conan.tools.cmake import cmake_layout, CMake, CMakeDeps, CMakeToolchain
+from conan.tools.env import Environment, VirtualBuildEnv
+from conan.tools.gnu import Autotools, AutotoolsToolchain
+from conan.tools.microsoft import unix_path
+
+
+# It will become the standard on Conan 2.x
+class TestPackageConan(ConanFile):
+    settings = "os", "arch", "compiler", "build_type"
+    test_type = "explicit"
+
+    @property
+    def _settings_build(self):
+        return getattr(self, "settings_build", self.settings)
+
+    def requirements(self):
+        self.requires(self.tested_reference_str, run=True)
+
+    def layout(self):
+        cmake_layout(self, src_folder="src")
+
+    def generate(self):
+
+        # Expose `PKG_CONFIG_PATH` to be able to find libexample1.pc
+        env = Environment()
+        self.output.info(f"Source folder: {self.source_folder}")
+        env.prepend_path("PKG_CONFIG_PATH", self.source_folder)
+        env.vars(self, scope="run").save_script("pkgconf-config-path")
+
+        # CMake project to test that we can link against the library,
+        # when the library is built
+        if self.dependencies[self.tested_reference_str].options.enable_lib:
+            ct = CMakeToolchain(self)
+            ct.generate()
+            deps = CMakeDeps(self)
+            deps.generate()
+
+        # Check build environment postconditions
+        buildenv = VirtualBuildEnv(self)
+        env = buildenv.vars(scope='build')
+        assert 'PKG_CONFIG' in env.keys()
+        assert 'ACLOCAL_PATH' in env.keys()
+        assert 'AUTOMAKE_CONAN_INCLUDES' in env.keys()
+        buildenv.generate()
+
+    @property
+    def _testing_library(self):
+        # Workaround, in Conan >=2.0 we should be able to remove this in favour of:
+        # self.dependencies[self.tested_reference_str].options.enable_lib
+        has_toolchain = sorted(Path(self.build_folder).rglob('conan_toolchain.cmake'))
+        return has_toolchain
+        
+    def build(self):
+        if self._testing_library:
+            cmake = CMake(self)
+            cmake.configure()
+            cmake.build()
+
+    def test(self):
+        # Check that we can find pkgconf in build environment
+        # and that it is the expected version
+        if can_run(self):
+            output = StringIO()
+            self.run("pkgconf --about", output, env="conanrun")
+            # TODO: When recipe is Conan 2+ only, this can be simplified
+            # to: self.dependencies['pkgconf'].ref.version
+            tokens = re.split('[@#]', self.tested_reference_str)
+            pkgconf_expected_version = tokens[0].split("/", 1)[1]
+            assert f"pkgconf {pkgconf_expected_version}" in output.getvalue() 
+
+            self.run("pkgconf libexample1 -cflags", env="conanrun")
+            
+        # Test that executable linked against library runs as expected
+        if can_run(self) and self._testing_library:
+            test_executable = unix_path(self, os.path.join(self.cpp.build.bindirs[0], "test_package"))
+            self.run(test_executable, env="conanrun")