From f612429d111af6fba58bb047fed44e054bcb6d9d Mon Sep 17 00:00:00 2001
From: Michael Lex <mich.lex@gmail.com>
Date: Thu, 1 May 2014 14:19:33 +0200
Subject: [PATCH] [JENKINS-20392] Fix "Recent History" for merge jobs.

To compute the recent-history, jenkins uses a hashmap of branch-names
and commit-ids. The bug has two sources:
1) To fill the hashmap, jenkins uses only the branch-name and
commit-ids of those commits, that triggered the build. The
merge-commits created by jenkins are ignored (see
BuildData.java#L129).
2) To calculate the "Recent Changes", jenkins searches for the
branch-names of the commit, that was built. But jenkins considers the
merge-commit not part of any branch (the call to getRevisionsForSHA1
in PreBuildMerge.java#L93 returns a Revision without associated
branches).

The patch fixes this bug by 1) including the branches of the current
commit in the recent-changes-hashmap and 2) associating the current
commit with the correct branch-name.
---
 .../hudson/plugins/git/extensions/impl/PreBuildMerge.java    | 5 ++++-
 src/main/java/hudson/plugins/git/util/BuildData.java         | 3 +++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/main/java/hudson/plugins/git/extensions/impl/PreBuildMerge.java b/src/main/java/hudson/plugins/git/extensions/impl/PreBuildMerge.java
index 81df102003..b54a7437b1 100644
--- a/src/main/java/hudson/plugins/git/extensions/impl/PreBuildMerge.java
+++ b/src/main/java/hudson/plugins/git/extensions/impl/PreBuildMerge.java
@@ -7,6 +7,7 @@
 import hudson.plugins.git.GitException;
 import hudson.plugins.git.GitSCM;
 import hudson.plugins.git.Revision;
+import hudson.plugins.git.Branch;
 import hudson.plugins.git.UserMergeOptions;
 import hudson.plugins.git.extensions.GitClientType;
 import hudson.plugins.git.extensions.GitSCMExtension;
@@ -90,7 +91,9 @@ public Revision decorateRevisionToBuild(GitSCM scm, AbstractBuild<?, ?> build, G
 
         build.addAction(new MergeRecord(remoteBranchRef,target.getName()));
 
-        return new GitUtils(listener,git).getRevisionForSHA1(git.revParse(HEAD));
+        Revision mergeRevision = new GitUtils(listener,git).getRevisionForSHA1(git.revParse(HEAD));
+        mergeRevision.getBranches().add(new Branch(remoteBranchRef, target));
+        return mergeRevision;
     }
 
     @Override
diff --git a/src/main/java/hudson/plugins/git/util/BuildData.java b/src/main/java/hudson/plugins/git/util/BuildData.java
index 34b2c97433..108bac4572 100644
--- a/src/main/java/hudson/plugins/git/util/BuildData.java
+++ b/src/main/java/hudson/plugins/git/util/BuildData.java
@@ -131,6 +131,9 @@ public void saveBuild(Build build) {
     	for(Branch branch : build.marked.getBranches()) {
             buildsByBranchName.put(fixNull(branch.getName()), build);
     	}
+        for(Branch branch : build.revision.getBranches()) {
+            buildsByBranchName.put(fixNull(branch.getName()), build);
+        }
     }
 
     public Build getLastBuildOfBranch(String branch) {