I’ve run into a similar problem with that path resolution and try_package_path when testing ppx updates with relative paths in “ppx-flags”:
"ppx-flags": ["../ppx"]
try_package_path: upward traversal did not find 'spice-ppx-test/../ppx' starting at...
I think it’s because it’s searching for spice-ppx-test, the name field from rescript.json, instead of the actual directory name?
I needed to use like "@greenlabs/ppx-spice": "workspace:../" in package.json so that @greenlabs/ppx-spice gets symlinked and use this instead in rescript.json.
"ppx-flags": ["@greenlabs/ppx-spice/ppx"]