Evaluate package conditions when generating ebuilds.

Ebuild generation was not utilizing package conditions.
Packages with multiple build types were causing hard failures during
ebuild generation but it's possible that invalid ebuilds were being
generated for other packages as well due to the lack of dependency
conditions.

superflore/generators/ebuild/gen_packages.py

@@ -120,6 +120,32 @@ def regenerate_pkg(overlay, pkg, distro, preserve_existing=False):
     return current, previous_version, pkg
 
 
+def _package_condition_context(rosdistro_name):
+    distro_properties = get_distros()[rosdistro_name]
+    ros_version = None
+    if distro_properties['distribution_type'] == 'ros2':
+        ros_version = '2'
+    elif distro_properties['distribution_type'] == 'ros1':
+        ros_version = '1'
+    else:
+        err("Superflore does not handle the distribution type '{}'".format(
+            distro_properties['distribution_type']))
+        raise 'Invalid distribution_type for {}'.format(rosdistro_name)
+    ros_python_version = None
+    if distro_properties['python_version'] == 3:
+        ros_python_version = '3'
+    elif distro_properties['python_version'] == 2:
+        ros_python_version = '2'
+    else:
+        err("Superflore does not handle the python version '{}'".format(
+            distro_properties['python_version']))
+        raise 'Invalid python_version for {}'.format(rosdistro_name)
+    return {
+            'ROS_DISTRO': rosdistro_name,
+            'ROS_VERSION': ros_version,
+            'ROS_PYTHON_VERSION': ros_python_version}
+
+
 def _gen_metadata_for_package(
     distro, pkg_name, repo, ros_pkg, pkg_rosinstall
 ):
@@ -129,7 +155,8 @@ def _gen_metadata_for_package(
     except Exception:
         warn("fetch metadata for package {}".format(pkg_name))
         return pkg_metadata_xml
-    pkg = PackageMetadata(pkg_xml)
+    package_condition_context = _package_condition_context(distro.name)
+    pkg = PackageMetadata(pkg_xml, evaluate_condition_context=package_condition_context)
     pkg_metadata_xml.upstream_email = pkg.upstream_email
     pkg_metadata_xml.upstream_name = pkg.upstream_name
     pkg_metadata_xml.longdescription = pkg.longdescription
@@ -146,7 +173,8 @@ def _gen_ebuild_for_package(
     pkg_ebuild.distro = distro.name
     pkg_ebuild.src_uri = pkg_rosinstall[0]['tar']['uri']
     pkg_names = get_package_names(distro)
-    pkg_dep_walker = DependencyWalker(distro)
+    package_condition_context = _package_condition_context(distro.name)
+    pkg_dep_walker = DependencyWalker(distro, evaluate_condition_context=package_condition_context)
 
     pkg_buildtool_deps = pkg_dep_walker.get_depends(pkg_name, "buildtool")
     pkg_build_deps = pkg_dep_walker.get_depends(pkg_name, "build")
@@ -181,7 +209,7 @@ def _gen_ebuild_for_package(
     except Exception:
         warn("fetch metadata for package {}".format(pkg_name))
         return pkg_ebuild
-    pkg = PackageMetadata(pkg_xml)
+    pkg = PackageMetadata(pkg_xml, evaluate_condition_context=package_condition_context)
     pkg_ebuild.upstream_license = pkg.upstream_license
     pkg_ebuild.description = pkg.description
     pkg_ebuild.homepage = pkg.homepage