Enable single-line annotations with pip-compile --annotation-style=line

[AndydeCleyre]

pip-compile gains --annotation-style=line which uses the recently discontinued single-line annotation format.

The current default behavior is unchanged, but can be explicitly passed as --annotation-style=split.

This aims to fix #1306. Please provide feedback!

Contributor checklist

• Provided the tests for the changes.
• Assure PR title is short, clear, and good to be included in the user-oriented changelog

Maintainer checklist

• Assure one of these labels is present: backwards incompatible, feature, enhancement, deprecation, bug, dependency, docs or skip-changelog as they determine changelog listing.
• Assign the PR to an existing or new milestone for the target version (following Semantic Versioning).

[reinout]

Small detail: the term "split". Would "verbose" or "multiline" be friendlier?

The verbose, multiline output is the default, so it seems a bit weird to use the term "split" as it is only "split" as opposed to the non-default "line" version.

Would a --single-line option without parameter be clearer? Then you only need to explain that it restores the old single-line-behaviour. You don't need to figure out a name for the default behaviour.

[AndydeCleyre]

Thanks for the feedback!

Small detail: the term "split". Would "verbose" or "multiline" be friendlier?

Multiline seems fine, but I don't prefer verbose, as we could have a more verbose single line annotation, theoretically. And it's not really more verbose anyway (no extra words).

Whatever maintainers and community want to call it.

Would a --single-line option without parameter be clearer?

Well not that exactly, because that doesn't indicate that this only affects the annotation (hashes still get their own lines). But the question of a single flag vs a parameter style argument is a good one.

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I don't personally care about these details, and am going to mark this as ready for review to hopefully gather answers to these and other questions from other maintainers.

[rsalmaso]

Nice! I was thinking about the same approach as #1297 was really a not good feature.

[ulope]

Added comments.
In general looks like it's doing what it says on the tin :)

[atugushev]

Looks good to me 👍🏻 Thanks for the work!

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I see the continuation backslash on the last generated --hash option is back again (gone in 5.5.0, see #1237). I presume there'll be some noise in users' VCS. Are we sure this is okay?

[AndydeCleyre]

Thanks @atugushev!

• I don't prefer to have that final trailing slash, but the reviewers before you do. 🤷‍♂️
• Do you think the style names can be improved?

[jdufresne]

I see the continuation backslash on the last generated --hash option is back again (gone in 5.5.0, see #1237). I presume there'll be some noise in users' VCS. Are we sure this is okay?

Thanks for linking this issue. I forgot that we intentionally removed this when I made a comment above 🤦. Yeah, lets not include the final trailing slash. (Sorry for the back and forth on this.)

[jdufresne]

Rest lgtm.

[AndydeCleyre]

Alright I've removed the continuation between the last hash and the annotation again, with apologies to @merwok and @ulope.

[AndydeCleyre]

All set, unless @atugushev or @jdufresne object to the latest commit.

[atugushev]

Thanks, @AndydeCleyre! 🎉

[atugushev]

Released in pip-tools v6.3.0 🚀