Emit post_lock after writing pyproject.toml and pdm.lock

[jantrienes]

Feature Description

We are trying to automatically generate platform-specific lockfiles whenever changes to the pyproject.toml were made. We tried using the post_lock lifecycle hook:

[tool.pdm.scripts]
post_lock = {composite = [
    "pdm lock --skip=post_lock --platform=manylinux_2_36_x86_64 --lockfile=pdm.lock.amd64 --with cpu",
    "pdm lock --skip=post_lock --platform=manylinux_2_36_aarch64 --lockfile=pdm.lock.arm64",
]}

However, this does not work for pdm add, because the post_lock event is emitted before the new pyproject.toml is written, meaning that the above pdm lock commands still operate on the "old" pyproject.toml file.

pdm/src/pdm/cli/commands/add.py

Lines 168 to 173 in 1867fba

	hooks.try_emit("post_lock", resolution=resolved, dry_run=dry_run)
	if not dry_run:
	project.add_dependencies(deps_to_update, group, selection.dev or False)
	project.write_lockfile(project.lockfile._data, False)
	if sync:
	do_sync(

As a workaround, we are using the post_install hook. This works, but this hook is also emitted in "clean" installs when no changes were made to the dependencies, triggering unnecessary lockfile generations.

Problem and Solution

Having the lockfile written to the disk before calling the post_lock hook would enable this functionality and make PDM's adoption easier for workflows that use platform-specific lockfiles.

Additional Context

I think this is analogous to #1224.

Are you willing to contribute to the development of this feature?

• Yes, I am willing to contribute to the development of this feature.