[JENKINS-4162] Optionally report the most recent commit as the changelog of a new build

[rhit-gawronja]

JENKINS-4162 - Implementing behavoir to handle JENKINS-4162

Looking to fix the behavior that is associated with push changes onto a brand new created branch. With these changes when the behavior is selected Jenkins will now present a changelog on the creation of a new branch. The changelog for the first build will be the most recent commit on the branch.

Other issue reports that are related and highlight the complexity of the general case include:

• JENKINS-14138 - Please guess the initial changeset (an idea)
• JENKINS-26354 - Please guess the initial changeset (another idea)
• JENKINS-68030 - Please guess the initial changeset

Git doesn't have the concept of a base branch. Many SCM providers (GitHub, Bitbucket, GitLab, Gitea, etc.) have a concept of a target branch, but the git plugin intentionally limits itself to the capabilities provided by command line git. Other plugins (like the GitHub branch source, Bitbucket branch source, GitLab branch source, and Gitea plugins) provide more capabilities and implement those capabilities using the specific APIs of the SCM provider.

Checklist

• I have read the CONTRIBUTING doc
• I have referenced the Jira issue related to my changes in one or more commit messages
• I have added tests that verify my changes
• Unit tests pass locally with my changes
• I have added documentation as necessary
• No Javadoc warnings were introduced with my changes
• No spotbugs warnings were introduced with my changes
• Documentation in README has been updated as necessary
• Online help has been added and reviewed for any new or modified fields
• I have interactively tested my changes

Types of changes

What types of changes does your code introduce?

• New feature (non-breaking change which adds functionality)

[UltimateGeek]

Consider updating the references to "changelog" in documentation to "changeset" to match the keyword used in Jenkinsfiles.

[UltimateGeek]

Copyright date should be this year.

Also, check to see if copyright dates may need to be updated in other files modified.

[MarkEWaite]

Copyright should not be assigned to CloudBees usually. Author usually retains copyright.

[rhit-inskeeda]

I have removed the CloudBees copyright documentation, would an author descriptor be adequate for this file?

[MarkEWaite]

Either is fine. If you want to declare copyright explicitly, that is fine. If you don't list it explicitly, the creation of the file makes it copyright by you implicitly.

Thanks for your contribution

[UltimateGeek]

I think this existing comment should be rewritten now that its within the context of the else case of the new option. But, perhaps just removing it would be best.

[rhit-gawronja]

I have seen this issue in other pull requests (#1556 (comment)) I was wondering if anyone had other insight into this issue of not passing the windows tests?

[MarkEWaite]

Needs documentation added to the README that describes how this is used in a Pipeline and how it is displayed to the user when they use the Pipeline snippet syntax generator inside their Jenkins controller.

I created a Pipeline with the Pipeline snippet syntax generator like this:

pipeline {
    agent any
    stages {
        stage('Checkout') {
            steps {
                checkout scmGit(branches: [[name: 'master']], 
                                extensions: [firstBuildChangelog(makeChangelog: true)], 
                                userRemoteConfigs: [[url: 'https://github.com/jenkinsci/git-plugin.git']])
            }
        }
    }
}

[UltimateGeek]

Hi @MarkEWaite, do you think the open items in the checklist in this PR can be checked off, and this merged?

[MarkEWaite]

Hi @MarkEWaite, do you think the open items in the checklist in this PR can be checked off, and this merged?

Thanks for asking.

I needed to make several changes to prepare for a final code review and interactive testing.

• reverted the massive changes that were injected by spotless in 5dfe120 . This repository is not yet ready for spotless to be run on all its source files. There are too many pending pull requests that would be disrupted by that large change.
• corrected the documentation to match the implemented behavior
• switched the help file from DOS line endings to Unix line endings

Interactive tests are needed to confirm there are no surprises that automation has missed.

[UltimateGeek]

I needed to make several changes to prepare for a final code review and interactive testing.

Thanks @MarkEWaite . I see the checklist item for the online help updates is still outstanding. Are there any changes with it you'd like @rhit-gawronja or @rhit-inskeeda to make?

[MarkEWaite]

Thanks @MarkEWaite . I see the checklist item for the online help updates is still outstanding. Are there any changes with it you'd like @rhit-gawronja or @rhit-inskeeda to make?

I've completed the changes in the online help and in the documentation. I don't see any further changes that are needed.