PkgConfig uses conanfile.run() instead of independent runner to u…

…se Conan environment (#13985)

* serialize cpp_info in package() for PkgConfig full functionality

* Update conan/tools/gnu/pkgconfig.py

Co-authored-by: Francisco Ramírez <franchuti688@gmail.com>

---------

Co-authored-by: Francisco Ramírez <franchuti688@gmail.com>

conan/tools/gnu/pkgconfig.py

@@ -1,7 +1,8 @@
+from io import StringIO
+
 from conan.tools.build import cmd_args_to_string
 from conan.tools.env import Environment
 from conan.errors import ConanException
-from conans.util.runners import check_output_runner
 
 
 class PkgConfig:
@@ -23,11 +24,16 @@ def __init__(self, conanfile, library, pkg_config_path=None):
     def _parse_output(self, option):
         executable = self._conanfile.conf.get("tools.gnu:pkg_config", default="pkg-config")
         command = cmd_args_to_string([executable, '--' + option, self._library, '--print-errors'])
+
         env = Environment()
         if self._pkg_config_path:
             env.prepend_path("PKG_CONFIG_PATH", self._pkg_config_path)
         with env.vars(self._conanfile).apply():
-            return check_output_runner(command).strip()
+            # This way we get the environment from ConanFile, from profile (default buildenv)
+            output = StringIO()
+            self._conanfile.run(command, stdout=output)
+        value = output.getvalue().strip()
+        return value
 
     def _get_option(self, option):
         if option not in self._info:

conans/test/functional/toolchains/gnu/test_pkg_config.py

@@ -1,7 +1,9 @@
+import platform
 import textwrap
 
 import pytest
 
+from conans.test.conftest import tools_locations
 from conans.test.utils.tools import TestClient
 
 
@@ -68,3 +70,67 @@ def generate(self):
         assert "conanfile.py: PROVIDES: libastral = 6.6.6" in c.out
         assert "conanfile.py: VERSION: 6.6.6" in c.out
         assert "conanfile.py: VARIABLES: /usr/local" in c.out
+
+
+def test_pkg_config_round_tripe_cpp_info():
+    """ test that serialize and deserialize CppInfo works
+    """
+    try:
+        version = tools_locations["pkg_config"]["default"]
+        exe = tools_locations["pkg_config"]["exe"]
+        os_ = platform.system()
+        pkg_config_path = tools_locations["pkg_config"][version]["path"][os_] + "/" + exe
+    except KeyError:
+        pytest.skip("pkg-config path not defined")
+        return
+
+    c = TestClient()
+    conanfile = textwrap.dedent("""
+        import os
+        from conan import ConanFile
+        from conan.tools.gnu import PkgConfig
+        from conan.tools import CppInfo
+
+        class Pkg(ConanFile):
+            name = "pkg"
+            version = "0.1"
+            exports_sources = "*.pc"
+
+            def package(self):
+                pkg_config = PkgConfig(self, "libastral", pkg_config_path=".")
+                cpp_info = CppInfo(self)
+                pkg_config.fill_cpp_info(cpp_info, is_system=False, system_libs=["m"])
+                cpp_info.save(os.path.join(self.package_folder, "cpp_info.json"))
+
+            def package_info(self):
+                self.cpp_info = CppInfo(self).load("cpp_info.json")
+        """)
+    prefix = "C:" if platform.system() == "Windows" else ""
+    libastral_pc = textwrap.dedent("""\
+        PC FILE EXAMPLE:
+
+        prefix=%s/usr/local
+        exec_prefix=${prefix}
+        libdir=${exec_prefix}/lib
+        includedir=${prefix}/include
+
+        Name: libastral
+        Description: Interface library for Astral data flows
+        Version: 6.6.6
+        Libs: -L${libdir}/libastral -lastral -lm -Wl,--whole-archive
+        Cflags: -I${includedir}/libastral -D_USE_LIBASTRAL
+        """ % prefix)
+    c.save({"conanfile.py": conanfile,
+            "libastral.pc": libastral_pc,
+            "profile": f"[conf]\ntools.gnu:pkg_config={pkg_config_path}"})
+    c.run("export .")
+    c.run("install --requires=pkg/0.1 -pr=profile -g CMakeDeps --build=missing")
+    pkg_data = c.load("pkg-none-data.cmake")
+    assert 'set(pkg_DEFINITIONS_NONE "-D_USE_LIBASTRAL")' in pkg_data
+    assert 'set(pkg_SHARED_LINK_FLAGS_NONE "-Wl,--whole-archive")' in pkg_data
+    assert 'set(pkg_COMPILE_DEFINITIONS_NONE "_USE_LIBASTRAL")' in pkg_data
+    assert 'set(pkg_LIBS_NONE astral)' in pkg_data
+    assert 'set(pkg_SYSTEM_LIBS_NONE m)' in pkg_data
+    # paths
+    assert f'set(pkg_INCLUDE_DIRS_NONE "{prefix}/usr/local/include/libastral")' in pkg_data
+    assert f'set(pkg_LIB_DIRS_NONE "{prefix}/usr/local/lib/libastral")' in pkg_data