Get started with fledge • fledge

library(fledge)

Do you want to provide a changelog (NEWS.md) more informative than “bug fixes and performance improvements” (https://twitter.com/EmilyKager/status/1413628436984188933) to the users of your package?

Ways to achieve that are:

Update NEWS.md right before release by reading through commit messages. Not necessarily fun!
Update the changelog in every commit e.g. in every PR. Now, if there are several feature PRs around that update the changelog, you’ll have a few clicks to make to tackle conflicts. Easy enough, but potentially annoying.
Use fledge to
- fill the NEWS.md for you based on informative commit messages,
- (optionally) increase the version number in DESCRIPTION (e.g. useful in bug reports with session information!),
- (optionally) create git tags (more coarse-grained history compared to top-level merges see fledge tag list on GitHub).

Using fledge is a discipline, a few habits, that are worth learning!

What you need to do in practice is, no matter your fledge commitment level:

For important commit messages you want recorded in the changelog, you can
- Use the conventional commits syntax. For instance feat: Enhanced support for time series. Only using conventional commits syntax will provide automatic grouping of changelog items into groups (Documentation, Bug Fixes, etc.).
- Add a hyphen - or * at the beginning of the commit message. Exclude housekeeping parts of the message by typing them after a line ---.
```
- Add support for bla databases.
```
or
```
- Add support for bla databases.

---

Also tweak the CI workflow accordingly. :sweat_smile:
```
- Use informative merge commit messages as those will also be included by default in the changelog. On GitHub you can control the default commit message when merging a pull request.
- (GitHub repositories only) For merge commits with the default not self-contained message (“Merge pull request…”), rely on fledge’s querying GitHub API to get the PR title and include it in the changelog.

For informative commit messages refer to the Tidyverse style guide.

Then, for full fledge use = fledge-assisted management of NEWS.md, DESCRIPTION version numbers, and git tags:

Run fledge::bump_version() regularly e.g. before every coffee break or at the end of the day or of the week. If you forgot to merge one PR run fledge::unbump_version(), merge the PR with an informative squash commit message, then run fledge::bump_version() and go drink that coffee!
Run fledge::finalize_version() if you need to edit NEWS.md manually e.g. if you made a typo or are not happy with a phrasing in retrospect. Even if you edit a lot, what’s been written in by fledge is still a good place-holder.
Follow the recommended steps at release (see vignette("fledge") usage section).

OR, for light fledge use = filling of NEWS.md between releases:

Have a development version header as produced by usethis::use_development_version().

# mypackage (development version)

Regularly run fledge::update_news(), preferentially on the main branch to avoid merge conflicts.

These habits are worth learning!

Installation & setup

Once per machine

Install from CRAN using:

install.packages("fledge")

Install from cynkra’s R-universe (development version) using:

install.packages("fledge", repos = c("https://cynkra.r-universe.dev", "https://cloud.r-project.org"))

Or install from GitHub (development version as well) using:

remotes::install_github("cynkra/fledge")

If you are used to making workflow packages (e.g. devtools) available for all your interactive work, you might enjoy loading fledge in your .Rprofile.

Once per package

Your package needs to have a remote that indicates the default branch (e.g. GitHub remote) or to be using the same default branch name as your global/project init.defaultbranch.
Add a mention of fledge usage in your contributing guide, as contributors might not know about it. A comment is added to the top of NEWS.md, but it tends to be ignored occasionally.

For full use

If your package…
- is brand-new, remember to run fledge::bump_version() regularly.
- has already undergone some development, it is not too late to jump on the train! Run fledge::bump_version() and then fledge::finalize_version().

For light use

Your package needs a development version header as produced by usethis::use_development_version().

# mypackage (development version)

Functions

{fledge} consists of the following functions that enable versioning at different stages through the package development lifecycle.

Function Name	Description	Stage Applicable
`bump_version(which)`	Increments the package version based on argument. (Version format supported major.minor.dev.patch)	Configuration, Development, Release
`finalize_version()`	Finalize the package version	Configuration, Development
`commit_version()`	Commits `NEWS.md` and `DESCRIPTION` to Git.	Release
`tag_version()`	Parses `NEWS.md` and creates/updates the tag for the most recent version.	Release
`update_news()`	Update `NEWS.md` with messages from top level commits; Update `NEWS.md` and `DESCRIPTION` with a new version	Used by `bump_version()`

Full fledge usage

The following sections show how to combine these functions at different stages with any R package on GitHub. All {fledge} commands should be issued from the package directory of the target R package.

Initial Configuration

{fledge} assumes that the target R package is version-controlled with Git in a dedicated repository. The following steps are required to set up {fledge} for first time use, with your package.

Call bump_version() as given below to set the package version
```
fledge::bump_version()
```
Edit NEWS.md if required (typo fixes, rephrasing, grouping).
Call finalize_version() as given below to update NEWS.md
```
fledge::finalize_version()
```

You are all set to switch to the development stage now. Ensure that you use bullet points (* or -) in your commit or merge messages to indicate the messages that you want to include in NEWS.md. Use finalize_version(push = TRUE) to push to the remote repository (e.g. GitHub) in one swoop.

Development

{fledge} aims to update NEWS.md and DESCRIPTION correctly whenever a new version is assigned. In order to do this, the following steps need to be included throughout the development workflow.

In commit messages to your main branch (typically main or master), mark everything that should go to NEWS.md with a bullet point (- or *). This is applicable to single commits, merge commits, or squash commits from pull requests. Do not edit NEWS.md manually.
When you want to assign a version number to the current state of your R package e.g. at the end of the day or before a break, call
```
fledge::bump_version()
```
The default argument for bump_version is “dev”. So the dev part of the version number will be updated. It is good practice to assign a new version number before switching focus to another project.
Edit NEWS.md if required (typo fixes, rephrasing, grouping).
Call finalize_version(): fledge::finalize_version(). This achieves the following:
- NEWS.md is now composed, based on the most recent commit messages. To understand how NEWS.md is updated by fledge, see the section on NEWS.md implementation.
- A new version number is assigned automatically (this is modeled after usethis::use_version()).
- A tag matching the version number is assigned automatically, with the most recent NEWS.md messages included in the tag’s message.

Releasing to CRAN

When you want to release your package to CRAN, follow the steps below:

Call bump_version() with the appropriate argument ("patch", "major", "minor"). e.g.,
```
fledge::bump_version("patch")
```
Edit NEWS.md, convert the “change log” to “release notes” – a higher-level description of features and bug fixes (typo fixes, rephrasing, grouping).
Call commit_version() as below
```
fledge::commit_version()
```
Make any necessary adjustments before releasing to CRAN depending on results of preparatory / incoming checks.
Once the release/changes have been accepted by CRAN, use the following calls to tag the released version and to switch to a development version immediately.
```
fledge::tag_version()
fledge::bump_version()
```
Return to development mode!

FAQ & edge cases

At least we think these questions could be asked. Feel free to also ask us questions!

But what if I want to edit NEWS.md manually?

You still can!

The best moment is between bump_version() and finalize_version(push = TRUE).
You can actually edit at any time, but only between those two calls the text in the changelog will be captured in the tag message, which is better for the tag history.

What if a contributor wants to contribute a NEWS item?

If someone opens a PR, with fledge the information about the changes should be entered in the message for the merge or squash commit. Now you could still advise contributors to provide a summary of the change as a comment to the PR.

Does this mean “Fix #42” will appear in NEWS.md?

If you want to fix an issue with a commit message you can

put “Fix #42” on a separate non-bulleted line or after a line with 3 hyphens.

- Adds support for coolness (#42, @contributor).

---

Fix #42

In a PR on e.g. GitHub you can link an issue to a PR by starting the first comment with “Fix 42” so the issue will be closed. The merge or squash commit will be hyperlinked to the PR, but the commit message won’t have that phrase. You should still add an acknowledgement in the actual commit message e.g. “- Adds support for coolness (#42, @contributor)”.

Edge cases

If you rebase after creating a tag, you need to call finalize_version() to make sure the tag is moved to the mainline branch.
If you pushed via finalize_version(push = TRUE) or git push, the tag may have been pushed as well. In this case, invoke

git push origin :vx.y.z.9www

(where x.y.z.9www is the new version) to delete the newly created remote tag. This is the reason why {fledge} only tags "dev" releases automatically. Other releases always must be tagged manually with tag_version().