Expand write_to_template to permit commit hash and date

[effigies]

While shifting a project to setuptools_scm, I saw someone ask if they could generate a copyright field dynamically based on the current year. Something like:

from datetime import datetime
__copyright__ = f"Copyright {datetime.today():%Y}, The Project X developers"

Obviously this would be bad, as the copyright would apply to the most recent change to the source code, not time of import. This information is available to setuptools_scm, and it could be useful to permit something like the following:

from datetime import datetime
from ._version import commit_date

__copyright__ = f"Copyright {datetime.fromisoformat(commit_date):%Y}, The Project X developers"

Is there any appetite to permit additional SCM-derived data in the generated file? I would imagine anything available in the ScmVersion data class would be potentially useful. Beyond saving a chore, generating more detailed bug report templates are the main other use case I can think of.

Anyway, any appetite for this? It could be done in a separate build tool plugin, but it would be nice to consolidate interaction with the SCM to a single utility.

[RonnyPfannschmidt]

There is a wish to add the scm version

Generating copyright based on recent dates is fundamentally broken

In particular it is absolutely useless for a autogenerated file

I recommend spdx aware pre commit hooks

[RonnyPfannschmidt]

@effigies also important warning - copyright does not start at the commit date - it can t best be used as the end of a range, else its wrong data

[effigies]

Fair points. Thanks for the feedback on the idea and apologies for leaving this open so long.

[RonnyPfannschmidt]

This is still planned as feature

[ZhiyuanChen]

It semms #854 can only help in terms of node.
I tried to add date, but it's impossible to strftime a date object inside a format call.

Maybe we need a new function like format_template to resolve this issue.

[RonnyPfannschmidt]

Date objects can uses strftime Style Formats in Format specifiers

[ZhiyuanChen]

Date objects can uses strftime Style Formats in Format specifiers

Ahhhh right! I've never noticed this behaviour before.
__date__ = {scm_version.node_date:%Y-%m-%d} would work

[RonnyPfannschmidt]

closing this as solves as the scm version is passed now