MergeValidationListener: Also provide RevWalk to the onPreMerge method

This way implementors that need a RevWalk do not need to create a new
instance. The callers have the RevWalk anyway available, so it's no
extra effort for them to provide it.

This makes the objects that are available to implementors of
MergeValidationListener more consistent with the objects that are
available to implementors of CommitValidationListener, which already
contains the RevWalk inside of CommitReceivedEvent.

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: Id93e378be10c91d3dc3365aec0bab9847ee8ef6d
(cherry picked from commit f57cdd0b5d)

java/com/google/gerrit/server/git/validators/MergeValidationListener.java

@@ -19,6 +19,7 @@ import com.google.gerrit.entities.PatchSet;
 import com.google.gerrit.extensions.annotations.ExtensionPoint;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.git.CodeReviewCommit;
+import com.google.gerrit.server.git.CodeReviewCommit.CodeReviewRevWalk;
 import com.google.gerrit.server.project.ProjectState;
 import org.eclipse.jgit.lib.Repository;
 
@@ -33,6 +34,7 @@ public interface MergeValidationListener {
    * Validate a commit before it is merged.
    *
    * @param repo the repository
+   * @param revWalk the rev walk
    * @param commit commit details
    * @param destProject the destination project
    * @param destBranch the destination branch
@@ -42,6 +44,7 @@ public interface MergeValidationListener {
    */
   void onPreMerge(
       Repository repo,
+      CodeReviewRevWalk revWalk,
       CodeReviewCommit commit,
       ProjectState destProject,
       BranchNameKey destBranch,

java/com/google/gerrit/server/git/validators/MergeValidators.java

@@ -35,6 +35,7 @@ import com.google.gerrit.server.config.GerritServerConfig;
 import com.google.gerrit.server.config.PluginConfig;
 import com.google.gerrit.server.config.ProjectConfigEntry;
 import com.google.gerrit.server.git.CodeReviewCommit;
+import com.google.gerrit.server.git.CodeReviewCommit.CodeReviewRevWalk;
 import com.google.gerrit.server.permissions.GlobalPermission;
 import com.google.gerrit.server.permissions.PermissionBackend;
 import com.google.gerrit.server.permissions.PermissionBackendException;
@@ -51,7 +52,6 @@ import java.util.Objects;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.lib.Repository;
-import org.eclipse.jgit.revwalk.RevWalk;
 
 /**
  * Collection of validators that run inside Gerrit before a change is submitted. The main purpose is
@@ -92,6 +92,7 @@ public class MergeValidators {
    */
   public void validatePreMerge(
       Repository repo,
+      CodeReviewRevWalk revWalk,
       CodeReviewCommit commit,
       ProjectState destProject,
       BranchNameKey destBranch,
@@ -106,7 +107,7 @@ public class MergeValidators {
             groupValidatorFactory.create());
 
     for (MergeValidationListener validator : validators) {
-      validator.onPreMerge(repo, commit, destProject, destBranch, patchSetId, caller);
+      validator.onPreMerge(repo, revWalk, commit, destProject, destBranch, patchSetId, caller);
     }
   }
 
@@ -168,11 +169,12 @@ public class MergeValidators {
 
     @Override
     public void onPreMerge(
-        final Repository repo,
-        final CodeReviewCommit commit,
-        final ProjectState destProject,
-        final BranchNameKey destBranch,
-        final PatchSet.Id patchSetId,
+        Repository repo,
+        CodeReviewRevWalk revWalk,
+        CodeReviewCommit commit,
+        ProjectState destProject,
+        BranchNameKey destBranch,
+        PatchSet.Id patchSetId,
         IdentifiedUser caller)
         throws MergeValidationException {
       if (RefNames.REFS_CONFIG.equals(destBranch.branch())) {
@@ -260,6 +262,7 @@ public class MergeValidators {
     @Override
     public void onPreMerge(
         Repository repo,
+        CodeReviewRevWalk revWalk,
         CodeReviewCommit commit,
         ProjectState destProject,
         BranchNameKey destBranch,
@@ -267,7 +270,7 @@ public class MergeValidators {
         IdentifiedUser caller)
         throws MergeValidationException {
       mergeValidationListeners.runEach(
-          l -> l.onPreMerge(repo, commit, destProject, destBranch, patchSetId, caller),
+          l -> l.onPreMerge(repo, revWalk, commit, destProject, destBranch, patchSetId, caller),
           MergeValidationException.class);
     }
   }
@@ -294,6 +297,7 @@ public class MergeValidators {
     @Override
     public void onPreMerge(
         Repository repo,
+        CodeReviewRevWalk revWalk,
         CodeReviewCommit commit,
         ProjectState destProject,
         BranchNameKey destBranch,
@@ -316,8 +320,9 @@ public class MergeValidators {
         throw new MergeValidationException("account validation unavailable");
       }
 
-      try (RevWalk rw = new RevWalk(repo)) {
-        List<String> errorMessages = accountValidator.validate(accountId, repo, rw, null, commit);
+      try {
+        List<String> errorMessages =
+            accountValidator.validate(accountId, repo, revWalk, null, commit);
         if (!errorMessages.isEmpty()) {
           throw new MergeValidationException(
               "invalid account configuration: " + Joiner.on("; ").join(errorMessages));
@@ -345,6 +350,7 @@ public class MergeValidators {
     @Override
     public void onPreMerge(
         Repository repo,
+        CodeReviewRevWalk revWalk,
         CodeReviewCommit commit,
         ProjectState destProject,
         BranchNameKey destBranch,

java/com/google/gerrit/server/submit/MergeOp.java

@@ -864,7 +864,8 @@ public class MergeOp implements AutoCloseable {
 
       MergeValidators mergeValidators = mergeValidatorsFactory.create();
       try {
-        mergeValidators.validatePreMerge(or.repo, commit, or.project, destBranch, ps.id(), caller);
+        mergeValidators.validatePreMerge(
+            or.repo, or.rw, commit, or.project, destBranch, ps.id(), caller);
       } catch (MergeValidationException mve) {
         commitStatus.problem(changeId, mve.getMessage());
         continue;