Add commit_range to template context

[jdrst]

Hey,

i would like to add links to diffs of certain files to the changelog.
Is there a way to get the commit range git cliff uses or was called with (in my case git cliff commitA..commitB)? As far as i could see it's not part of the context.

Thanks

[welcome]

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[orhun]

Good idea! We simply need to add commit_range to Release struct and update the other parts accordingly. See #721 for an example.

Marking this as good-first-issue, would you be interested in contributing?

[jdrst]

i'll try to make some time next week and have a look.

[orhun]

Perfect, assigned to you! Let me know if you need any assistance.

[jdrst]

Hey,

i finally could make the time to have a look. Unless i'm overlooking something this might not be as straight forward as thought. Here are my observations:

Currently the commit range is passed when getting the commits for changelog creation, we don't have ownership of the repo there.
As far as i could tell, we might not even "know" the actual commits used, at that time, because they might be internal to the revwalker. What we (afterwards) do have, is a list of sorted commits that is produced. So it might be possible to add something here akin to

//...
	let first_commit = commits.first().unwrap().id();
	let last_commit = commits.last().unwrap().id();
	let commit_range =
		CommitRange::new(&first_commit.to_string(), &last_commit.to_string());
	for git_commit in commits.iter().rev() {
		let release = releases.last_mut().unwrap();
                //..
		release.commit_range = Some(commit_range.clone());
// ...

with

/// Commit range (from..to)
pub struct CommitRange {
	from: String,
	to:   String,
}

From what i could tell this is currently not easily testable though, right?

Let me know your thoughts.

[Cyclonit]

Can you elaborate on the use case for this request? Do you want to generate a diff between a change's commit and the previous release?

[orhun]

Do you want to generate a diff between a change's commit and the previous release?

I think yes... I cannot think of another use case.

As far as i could tell, we might not even "know" the actual commits used, at that time, because they might be internal to the revwalker.

Hmm yeah, good point.

let commit_range =
CommitRange::new(&first_commit.to_string(), &last_commit.to_string());

Yup, that looks good to me. I think that would be the most correct way of getting the range.

From what i could tell this is currently not easily testable though, right?

Can you elaborate this a bit? What do you want to do exactly?

[jdrst]

Can you elaborate on the use case for this request? Do you want to generate a diff between a change's commit and the previous release?

yes, as stated:

i would like to add links to diffs of certain files to the changelog.

in my case this would be achieveable via the commit hashes

Can you elaborate this a bit? What do you want to do exactly?

my proposal would put the logic in fn process_repository - looking at references i couldn't find a test that runs that logic.
a quick check locally with an actual project produced results that were not what i was expecting and i'd like to look at it more isolated

[orhun]

I think we can use test fixtures for testing this functionality in the first phase. And yes, I think process_repository is a good place to implement it 👍🏼

[jdrst]

Ah, missed those. It looks like commits are created "on the fly" there. Any quick idea how i can deterministically create the same commit sha every time? Apply patches?
Or is there another way to put those in the expected.md?

I'll try to get a pr going some time soon.

[orhun]

Good question. I think applying patches might work. Or we can install a tool like lucky_commit in CI to generate hashes like 1010101 etc. It might be a bit of an overkill though.

Edit: Just do this in commit.sh to use an already existing repo:

#!/usr/bin/env bash
set -e

git remote add origin https://github.com/orhun/git-cliff-readme-example
git pull origin master
git fetch --tags