Gradle 3.1 change: "replaced" change type breaks compatibility with existing plugin

[ducrohet]

The change adds a new ChangeType value REPLACED (reference: 0a4a3bb). This leads to two issues:

FileChange has not been updated to provide a isReplaced() method so plugins cannot query for this kind of file change. Because OrderSensitiveTaskFilePropertyCompareStrategy has been changed to exclusively use the new status instead of MODIFIED some file changes cannot be detected by new task implementations.

However a bigger problems is that existing plugins that go through IncrementalTaskInputs.outofDate looking at isModified() will also always miss the files that use the new status. The only fix is to release a new version of the plugin (after the new API is fixed with a new isReplaced() method).

In order to be compatible, I believe Gradle should make these replaced files return true for both isModified() and isReplaced(). This require some more refactoring as FileChange only support a single ChangeType.

The Gradle plugin for Android is failing some of its tests on 3.1 because of this.

• JIRA issue: GRADLE-3577
• Internal review: REVIEW-6345

[lptr]

FTR: the task output cache team is tracking this issue as ☝️.

[wolfs]

LGTM. I think we should open a JIRA issue (this affect 3.1, right)? Should we also add something to the release notes apart from the JIRA issue which will be automatically added? I think the issue should be enough.

[lptr]

Added JIRA issue. I also think it should be enough for the release notes.

[eriwen]

Closing as delivered in Gradle 3.2