Skip rosidl_generate_interfaces dependency export on SKIP_INSTALL. (#708)

* Skip rosidl_generate_interfaces dependency export on SKIP_INSTALL.

When a dependency is declared in rosidl_generate_interfaces(),
ament_export_dependencies() for that dependency is automatically
called.  That is the correct default behavior, but it isn't always
the behavior that is wanted.  In particular, if a package has
messages that are only used for tests, we don't want to export
those dependencies downstream.  If SKIP_INSTALL is specified,
skip exporting the dependencies downstream.

Signed-off-by: Chris Lalancette <[email protected]>

Author: clalancette

rosidl_cmake/cmake/rosidl_generate_interfaces.cmake

@@ -41,8 +41,8 @@
 # :type LIBRARY_NAME: string
 # :param SKIP_INSTALL: if set skip installing the interface files
 # :type SKIP_INSTALL: option
-# :param SKIP_GROUP_MEMBERSHIP_CHECK: if set, skip enforcing the appartenance
-#   to the rosidl_interface_packages group
+# :param SKIP_GROUP_MEMBERSHIP_CHECK: if set, skip enforcing membership in the
+#   rosidl_interface_packages group
 # :type SKIP_GROUP_MEMBERSHIP_CHECK: option
 # :param ADD_LINTER_TESTS: if set lint the interface files using
 #   the ``ament_lint`` package
@@ -66,7 +66,9 @@ macro(rosidl_generate_interfaces target)
   endif()
 
   _rosidl_cmake_register_package_hook()
-  ament_export_dependencies(${_ARG_DEPENDENCIES})
+  if(NOT _ARG_SKIP_INSTALL)
+    ament_export_dependencies(${_ARG_DEPENDENCIES})
+  endif()
 
   # check that passed interface files exist
   # a tuple with an absolute base and a relative path is returned as is