enhance mergeCommandBuilder API with setMessage to avoid templating commit messages

scm-core/src/main/java/sonia/scm/repository/api/MergeCommandBuilder.java

@@ -181,6 +181,18 @@ public class MergeCommandBuilder {
     return this;
   }
 
+  /**
+   * Use this to set the commit message. If no message is set, the message template will be used.
+   *
+   * This is optional and for {@link #executeMerge()} only.
+   *
+   * @return This builder instance.
+   */
+  public MergeCommandBuilder setMessage(String message) {
+    request.setMessage(message);
+    return this;
+  }
+
   /**
    * Use this to reset the command.
    * @return This builder instance.

scm-core/src/main/java/sonia/scm/repository/spi/MergeCommandRequest.java

@@ -42,6 +42,7 @@ public class MergeCommandRequest implements Validateable, Resetable, Serializabl
   private String targetBranch;
   private Person author;
   private String messageTemplate;
+  private String message;
   private MergeStrategy mergeStrategy;
   private boolean sign = true;
 
@@ -77,6 +78,14 @@ public class MergeCommandRequest implements Validateable, Resetable, Serializabl
     this.messageTemplate = messageTemplate;
   }
 
+  public String getMessage() {
+    return message;
+  }
+
+  public void setMessage(String message) {
+    this.message = message;
+  }
+
   public MergeStrategy getMergeStrategy() {
     return mergeStrategy;
   }

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitMergeStrategy.java

@@ -56,6 +56,7 @@ abstract class GitMergeStrategy extends AbstractGitCommand.GitCloneWorker<MergeC
   private final ObjectId revisionToMerge;
   private final Person author;
   private final String messageTemplate;
+  private final String message;
   private final boolean sign;
 
   GitMergeStrategy(Git clone, MergeCommandRequest request, GitContext context, sonia.scm.repository.Repository repository) {
@@ -64,6 +65,7 @@ abstract class GitMergeStrategy extends AbstractGitCommand.GitCloneWorker<MergeC
     this.branchToMerge = request.getBranchToMerge();
     this.author = request.getAuthor();
     this.messageTemplate = request.getMessageTemplate();
+    this.message = request.getMessage();
     this.sign = request.isSign();
     try {
       this.targetRevision = resolveRevision(request.getTargetBranch());
@@ -106,10 +108,12 @@ abstract class GitMergeStrategy extends AbstractGitCommand.GitCloneWorker<MergeC
   }
 
   private String determineMessage() {
-    if (Strings.isNullOrEmpty(messageTemplate)) {
+    if (!Strings.isNullOrEmpty(message)) {
-      return MessageFormat.format(MERGE_COMMIT_MESSAGE_TEMPLATE, branchToMerge, targetBranch);
+      return message;
+    } else if (!Strings.isNullOrEmpty(messageTemplate)) {
+      return MessageFormat.format(messageTemplate, branchToMerge, targetBranch);
     } else {
-      return messageTemplate;
+      return MessageFormat.format(MERGE_COMMIT_MESSAGE_TEMPLATE, branchToMerge, targetBranch);
     }
   }