[Buildbot] #2680: sourcestamp merging with no changes uses revision of oldest instead of newest

[Buildbot trac]

#2680: sourcestamp merging with no changes uses revision of oldest instead of
newest
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Reporter:  brendan  |       Owner:
    Type:  defect   |      Status:  new
Priority:  major    |   Milestone:  undecided
 Version:  0.8.5    |  Resolution:
Keywords:           |
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Comment (by dcoshea):

 It certainly makes sense to me to service buildrequests starting with the
 oldest (unless nextBuild has been used), but when requests are merged to
 use the sourcestamp from the newest request.

 I have a builder driven by a `SingleBranchScheduler` with multiple
 codebases, where all the Changes in one of the codebases are marked as
 unimportant using fileIsImportant, and where I've overridden mergeRequests
 to allow merging of buildrequests from different codebases.  The builder
 takes a long time to finish a build compared to the frequency of commits,
 so there will frequently be a lot of merging.  What happens then is that
 commits to most of the codebases will all be built in the next build that
 starts, but commits to the unimportant codebase don't get built until the
 one after that (unless they went in before the first commit to an
 important codebase).

 I'd like to try the patch but Trac says "Attachment 'nochanges.diff' not
 found" :(

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Ticket URL: <http://trac.buildbot.net/ticket/2680#comment:3>
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