xacro_add_files fails if another file in the current building package is included in the file

[Yuki Furuta]

The cmake function xacro_add_files fails when the target xacro file has include tags which has the path to files in the current package.
It looks this is because we cannot find the current building package using ament_index system.
Is there any fix or workaround?

Here is how to reproduce the issue:

Given a test_pkg in a workspace:

• src/test_pkg/CMakeLists.txt

cmake_minimum_required(VERSION 3.8)
project(test_pkg)

find_package(ament_cmake REQUIRED)
find_package(xacro REQUIRED)

xacro_add_files(foo.urdf.xacro TARGET foo)

ament_package()

• src/test_pkg/foo.urdf.xacro

<?xml version="1.0" encoding="utf-8"?>
<robot name="robot" xmlns:xacro="http://www.ros.org/wiki/xacro">
  <xacro:include filename="$(find test_pkg)/bar.urdf.xacro"/>
</robot>

• src/test_pkg/bar.urdf.xacro

<?xml version="1.0" encoding="utf-8"?>
<robot xmlns:xacro="http://www.ros.org/wiki/xacro">
</robot>

Run colcon build fails on error:

$ source /opt/ros/humble/setup.bash
$ colcon build --symlink-install
Starting >>> test_pkg
--- stderr: test_pkg                              
CMake Warning at /opt/ros/humble/share/xacro/cmake/xacro-extras.cmake:74 (message):
  failed to determine deps for: foo.urdf.xacro

  error: package not found: "package 'test_pkg' not found, searching:
  ['/opt/ros/humble']"

  when processing file: foo.urdf.xacro

Call Stack (most recent call first):
  /opt/ros/humble/share/xacro/cmake/xacro-extras.cmake:133 (xacro_add_xacro_file)
  CMakeLists.txt:12 (xacro_add_files)


package not found: "package 'test_pkg' not found, searching: ['/opt/ros/humble']"
when processing file: foo.urdf.xacro
gmake[2]: *** [CMakeFiles/test_pkg_foo.dir/build.make:73: foo.urdf] Error 2
gmake[1]: *** [CMakeFiles/Makefile2:137: CMakeFiles/test_pkg_foo.dir/all] Error 2
gmake: *** [Makefile:146: all] Error 2
---
Failed   <<< test_pkg [0.47s, exited with code 2]

Summary: 0 packages finished [0.57s]
  1 package failed: test_pkg
  1 package had stderr output: test_pkg

[Robert Haschke]

I don't have a clean solution to this problem. See #326 for an intermediate workaround.

[Yuki Furuta]

Thank you for addressing this issue! I hope there should be a way that the current package path is resolved at build time.

[Robert Haschke]

The downside of #326 is if any custom destination is set in install function in CMakeLists.txt, it will not work.

@furushchev, can you please elaborate on this statement? I don't yet see a limitation.

[Yuki Furuta]

@rhaschke
Given that there is urdf directory in the project, if the install function is set as followings:

install(DIRECTORY urdf DESTINATION share/${PROJECT_NAME}/resources)

The file can only be looked up as $(find pkg)/resources/urdf/foo.urdf.xacro, which is different from the location in the source directory $(find pkg)/urdf/foo.urdf.xacro.

However, it is really edge case (and it is not supported in ROS1 too), so I think we can ignore it anyway.

[Robert Haschke]

I see. But the same issue arises in ROS1: build-space and install-space paths have to be the same.

[Yuki Furuta]

But the same issue arises in ROS1: build-space and install-space paths have to be the same.

Thank you for the answer. Yes, I just now realized the same thing, sorry for confusion.

[Robert Haschke]

Closed via #326.