Refactored conan.tools.gnu.pkgconfigdeps module and added new `pkg_…

…config_aliases` property (#10084)

* Restructured the mechanism to declare an 'alias' in PkgConfigDeps

* Added and modified several tests to check the set_property is working

* Added more docstrings for tests and added another case

* Allowing lists as valid  pkg_config_name value, e.g., ['name1', 'alias1']

* wip - moving tons of code

* Tests passing and completed new pkgconfigdeps module structure

* Deleted useless test

* Added checks in case of foo::foo components

* Changed 'wrapper' word to 'alias' instead. It's clearer than wrapper

* Refactored all the help modules. Now, it's more functional

* Added conanfile as first argument. Needed for GnuDepsFlags

conan/tools/gnu/__init__.py

@@ -1,4 +1,4 @@
 from conan.tools.gnu.autotoolstoolchain import AutotoolsToolchain
 from conan.tools.gnu.autotoolsdeps import AutotoolsDeps
 from conan.tools.gnu.autotools import Autotools
-from conan.tools.gnu.pkgconfigdeps import PkgConfigDeps
+from conan.tools.gnu.pkgconfigdeps.pkgconfigdeps import PkgConfigDeps

conan/tools/gnu/pkgconfigdeps/pc_files_creator.py

@@ -0,0 +1,89 @@
+from conan.tools.gnu.pkgconfigdeps.pc_files_templates import get_alias_pc_filename_and_content, \
+    get_pc_filename_and_content
+from conan.tools.gnu.pkgconfigdeps.pc_info_loader import get_package_with_components_info, \
+    get_single_package_info, get_aliases_info
+
+
+def _get_aliases_pc_files_and_content(dep, aliases_info):
+    """
+    Get all the PC files and content for the aliases defined previously
+    for package and components names
+    """
+    pc_files = {}
+    for name, aliases in aliases_info.items():
+        for alias in aliases:
+            pc_alias_file = get_alias_pc_filename_and_content(
+                dep,
+                alias,
+                [name],  # require is the own name which is being used the aliases for.
+                description="Alias %s for %s" % (alias, name),
+            )
+            pc_files.update(pc_alias_file)
+    return pc_files
+
+
+def _get_components_pc_files_and_content(conanfile, dep, components_info):
+    """
+    Get the PC files and content for dependency's components
+    """
+    pc_files = {}
+    # Loop through all the package's components
+    for pc_info_component in components_info:
+        # Get the *.pc file content for each component
+        description = "Conan component: %s" % pc_info_component.name
+        pc_file = get_pc_filename_and_content(
+            conanfile,
+            dep,
+            pc_info_component.name,
+            pc_info_component.requires,
+            description,
+            cpp_info=pc_info_component.cpp_info)
+        pc_files.update(pc_file)
+    return pc_files
+
+
+def _get_package_with_components_pc_files_and_content(conanfile, dep, package_info, components_info):
+    """
+    Get the PC files and content for dependencies with components
+    """
+    pc_files = {}
+    pc_files.update(_get_components_pc_files_and_content(conanfile, dep, components_info))
+    description = "Conan package: %s" % package_info.name
+    pc_alias_file_pkg = get_alias_pc_filename_and_content(
+        dep,
+        package_info.name,
+        package_info.requires,
+        description
+    )
+    pc_files.update(pc_alias_file_pkg)
+    return pc_files
+
+
+def _get_single_package_pc_file_and_content(conanfile, dep, package_info):
+    """
+    Get the PC files for dependencies without components
+    """
+    description = "Conan package: %s" % package_info.name
+    pc_file = get_pc_filename_and_content(conanfile, dep, package_info.name,
+                                          package_info.requires, description)
+    return pc_file
+
+
+def get_pc_files_and_content(conanfile, dep):
+    """
+    Get all the PC files given a dependency (package, components and alias ones)
+    """
+    pc_files = {}
+    if dep.cpp_info.has_components:  # Package with components
+        pkg_info, components_info = get_package_with_components_info(dep)
+        pc_files.update(_get_package_with_components_pc_files_and_content(conanfile, dep, pkg_info,
+                                                                          components_info))
+    else:
+        # Package without components
+        pkg_info = get_single_package_info(dep)
+        components_info = []
+        pc_files.update(_get_single_package_pc_file_and_content(conanfile, dep, pkg_info))
+    # Package and components names aliases
+    aliases_info = get_aliases_info(dep, pkg_info, components_info)
+    pc_files.update(_get_aliases_pc_files_and_content(dep, aliases_info))
+    return pc_files