From 83cc1c4a6ff2a71eb207509649da6efed5d57532 Mon Sep 17 00:00:00 2001
From: Eduard Heimbuch <eduard.heimbuch@cloudogu.com>
Date: Wed, 18 Dec 2019 13:17:30 +0100
Subject: [PATCH] return revision on merge

---
 .../repository/api/MergeCommandResult.java    | 22 +++++++------------
 .../spi/GitFastForwardIfPossible.java         |  2 +-
 .../scm/repository/spi/GitMergeStrategy.java  |  2 +-
 .../repository/spi/GitMergeWithSquash.java    |  4 ++--
 .../sonia/scm/repository/spi/GitMerger.java   |  3 ++-
 5 files changed, 14 insertions(+), 19 deletions(-)

diff --git a/scm-core/src/main/java/sonia/scm/repository/api/MergeCommandResult.java b/scm-core/src/main/java/sonia/scm/repository/api/MergeCommandResult.java
index 54b57c668f..5680416925 100644
--- a/scm-core/src/main/java/sonia/scm/repository/api/MergeCommandResult.java
+++ b/scm-core/src/main/java/sonia/scm/repository/api/MergeCommandResult.java
@@ -1,9 +1,7 @@
 package sonia.scm.repository.api;
 
 import java.util.Collection;
-import java.util.HashSet;
 
-import static java.util.Collections.emptyList;
 import static java.util.Collections.unmodifiableCollection;
 
 /**
@@ -13,19 +11,15 @@ import static java.util.Collections.unmodifiableCollection;
  */
 public class MergeCommandResult {
   private final Collection<String> filesWithConflict;
-  private static String mergeCommitRevision;
+  private String newHeadRevision;
 
-  public MergeCommandResult(Collection<String> filesWithConflict, String mergeCommitRevision) {
+  public MergeCommandResult(Collection<String> filesWithConflict) {
     this.filesWithConflict = filesWithConflict;
-    this.mergeCommitRevision = mergeCommitRevision;
   }
 
-  public static MergeCommandResult success() {
-    return new MergeCommandResult(emptyList(), mergeCommitRevision);
-  }
-
-  public static MergeCommandResult failure(Collection<String> filesWithConflict) {
-    return new MergeCommandResult(new HashSet<>(filesWithConflict), "");
+  public MergeCommandResult(Collection<String> filesWithConflict, String newHeadRevision) {
+    this.filesWithConflict = filesWithConflict;
+    this.newHeadRevision = newHeadRevision;
   }
 
   /**
@@ -33,7 +27,7 @@ public class MergeCommandResult {
    * merge conflicts. In this case you can use {@link #getFilesWithConflict()} to check what files could not be merged.
    */
   public boolean isSuccess() {
-    return filesWithConflict.isEmpty();
+    return filesWithConflict.isEmpty() && newHeadRevision != null;
   }
 
   /**
@@ -44,7 +38,7 @@ public class MergeCommandResult {
     return unmodifiableCollection(filesWithConflict);
   }
 
-  public String getMergeCommitRevision() {
-    return mergeCommitRevision;
+  public String getNewHeadRevision() {
+    return newHeadRevision;
   }
 }
diff --git a/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitFastForwardIfPossible.java b/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitFastForwardIfPossible.java
index ddca0a78b0..cf03e832a3 100644
--- a/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitFastForwardIfPossible.java
+++ b/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitFastForwardIfPossible.java
@@ -23,7 +23,7 @@ class GitFastForwardIfPossible extends GitMergeStrategy {
     MergeResult fastForwardResult = mergeWithFastForwardOnlyMode();
     if (fastForwardResult.getMergeStatus().isSuccessful()) {
       push();
-      return new MergeCommandResult(Collections.emptyList(), "");
+      return new MergeCommandResult(Collections.emptyList(), fastForwardResult.getNewHead().toString());
     } else {
       return fallbackMerge.run();
     }
diff --git a/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMergeStrategy.java b/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMergeStrategy.java
index 17b4571820..16048c1ef6 100644
--- a/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMergeStrategy.java
+++ b/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMergeStrategy.java
@@ -69,6 +69,6 @@ abstract class GitMergeStrategy extends AbstractGitCommand.GitCloneWorker<MergeC
 
   MergeCommandResult analyseFailure(MergeResult result) {
     logger.info("could not merge branch {} into {} due to conflict in paths {}", toMerge, target, result.getConflicts().keySet());
-    return MergeCommandResult.failure(result.getConflicts().keySet());
+    return new MergeCommandResult(result.getConflicts().keySet());
   }
 }
diff --git a/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMergeWithSquash.java b/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMergeWithSquash.java
index a1e921e8a9..d50ff1737d 100644
--- a/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMergeWithSquash.java
+++ b/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMergeWithSquash.java
@@ -1,11 +1,11 @@
 package sonia.scm.repository.spi;
 
 import org.eclipse.jgit.api.Git;
+import org.eclipse.jgit.api.MergeCommand;
 import org.eclipse.jgit.api.MergeResult;
 import org.eclipse.jgit.revwalk.RevCommit;
 import sonia.scm.repository.Repository;
 import sonia.scm.repository.api.MergeCommandResult;
-import org.eclipse.jgit.api.MergeCommand;
 
 import java.io.IOException;
 import java.util.Collections;
@@ -21,7 +21,7 @@ class GitMergeWithSquash extends GitMergeStrategy {
 
   @Override
   MergeCommandResult run() throws IOException {
-   MergeCommand mergeCommand = getClone().merge();
+    MergeCommand mergeCommand = getClone().merge();
     mergeCommand.setSquash(true);
     MergeResult result = doMergeInClone(mergeCommand);
 
diff --git a/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMerger.java b/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMerger.java
index 87334e5a57..6fe942ed7e 100644
--- a/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMerger.java
+++ b/scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMerger.java
@@ -1,5 +1,6 @@
 package sonia.scm.repository.spi;
 
+import org.eclipse.jgit.api.MergeResult;
 import org.eclipse.jgit.revwalk.RevCommit;
 import sonia.scm.ContextEntry;
 import sonia.scm.repository.InternalRepositoryException;
@@ -12,6 +13,6 @@ public class GitMerger {
     if (revCommit.isPresent()) {
       return revCommit.get().toString().split(" ")[1];
     }
-    throw new InternalRepositoryException(ContextEntry.ContextBuilder.entity(GitMergeCommit.class, "merge commit failed"), "could not create commit on merge");
+    throw new InternalRepositoryException(ContextEntry.ContextBuilder.entity(GitMerger.class, "merge commit failed"), "could not create commit on merge");
   }
 }