Bug report

Required Info:

• Operating System:
  • Ubuntu 20.04
• Installation type:
  • binaries
• Version or commit hash:
  • up to date
• DDS implementation:
  • irrelevant
• Client library (if applicable):
  • irrelevant

Steps to reproduce issue

Create file test.launch.yaml.

launch:
  - executable:
      cmd: echo $(dirname)
      name: obvious
      output: screen
  - include:
      file: $(find-pkg-share some_package)/file.launch.yaml
  - executable:
      cmd: echo $(dirname)
      name: surprise
      output: screen

The file file.launch.yaml in some_package:

launch: []

Run ros2 launch test.launch.yaml.

Expected behavior

echo $(dirname) outputs the path to test.launch.yaml each time.

Actual behavior

echo $(dirname) outputs the path to test.launch.yaml the first time and the path to the package share of some_package the second time. It appears that "the context" is somehow not reset. Is this really intentional? I also could not find the docs for that substitution.

Additional information

launch:
  - executable:
      cmd: echo $(dirname)
      name: obvious
      output: screen
  - executable:
      cmd: echo $(find-pkg-share some_package)
      name: testing_this
      output: screen
  - executable:
      cmd: echo $(dirname)
      name: surprise
      output: screen

In this setting echo $(dirname) outputs the path to test.launch.yaml each time.

Implementation considerations

It is very unexpected but also breaking when changed.