Seems like the same problem could arise without folders, by editing Jenkins.buildsDir, though this would presumably be rare.

The most obvious solution would be to deprecate AbstractLazyLoadRunMap.<init>(File) as well as related methods/constructors, and replace it with a () -> File callback. Not sure if there would be a significant performance impact of recalculating getBuildDir() whenever dir is currently used.

Alternately, have each AbstractProject listen for renames of its parent ItemGroup as well as changes in buildsDir, and rerun createBuildRunMap when that happens. Less expensive in the normal case, more expensive when a rename does occur.

Not an lts-candidate since fix requires APIs not expected to be backported to the current LTS line.

Code changed in jenkins
User: Jesse Glick
Path:
changelog.html
core/src/main/java/hudson/model/AbstractProject.java
test/src/test/groovy/hudson/model/AbstractProjectTest.groovy
http://jenkins-ci.org/commit/jenkins/cb623640ccd820ad0540efc3b50cc596626e43a2
Log:
[FIXED JENKINS-18694] Generalizing fix of JENKINS-18678 to include also rename of parent folders, taking advantage of JENKINS-18028 API.

Integrated in jenkins_main_trunk #3160
[FIXED JENKINS-18694] Generalizing fix of JENKINS-18678 to include also rename of parent folders, taking advantage of JENKINS-18028 API. (Revision cb623640ccd820ad0540efc3b50cc596626e43a2)

Result = SUCCESS
Jesse Glick : cb623640ccd820ad0540efc3b50cc596626e43a2
Files :

• test/src/test/groovy/hudson/model/AbstractProjectTest.groovy
• core/src/main/java/hudson/model/AbstractProject.java
• changelog.html