add object representation and conversion from ast

[dirk-thomas]

This is the fifth PR integrating #298 step-by-step.

Builds on top of #325. Needs ros2/ci#220.

After lark parses any input file the AST is converted to an object representation (which will later be passed into the message generator templates).

Linux CI:

[sloretz]

Partial review. I have some questions about the definitions. With those answers I'll be better able to review the parser.

[dirk-thomas]

Just another CI after the changes:

[dirk-thomas]

Sill good with the common.lark file removed:

[sloretz]

LGTM for now with a minor fix. There are limitations that should be ticketed like includes in modules and different constants in different messages. Tests with IDL files that are acceptable to the grammar but illogical, like a boolean constant being assigned a string value, would be good too, but that can be ticketed rather than blocking the remaining PRs.

[dirk-thomas]

Thanks. I created #329 for the followup improvements.

Squashing the commits before the merge...

[sloretz]

green check mark

[dirk-thomas]

green check mark

That is very suspicious because the PR job has no way of pulling the lark-parser until we have a Debian package for it... 🤔

[dirk-thomas]

Full build:

[dirk-thomas]

@ros-pull-request-builder retest this please

[dirk-thomas]

Waiting for the python3-lark-parser Debian package...

[dirk-thomas]

• Linux
• Linux-aarch64
• macOS
• Windows
  • test failure due to encoding:
  • fixed in 49d24f2
  • rerun of the specific test only: