Don't crash in GetAccess if refs/meta/config is missing

Change-Id: I6ad1b9802d104d2dac4fc4d20f9478bfde5bccdf

java/com/google/gerrit/server/restapi/project/GetAccess.java

@@ -156,13 +156,16 @@ public class GetAccess implements RestReadView<ProjectResource> {
       config = ProjectConfig.read(md);
       info.configWebLinks = new ArrayList<>();
 
-      // WebLinks operates in terms of the data types used in the GWT UI. Once the GWT UI is gone,
+      // config may have a null revision if the repo doesn't have its own refs/meta/config.
-      // WebLinks should be fixed to use the extension data types.
+      if (config.getRevision() != null) {
+        // WebLinks operates in terms of the data types used in the GWT UI. Once the GWT UI is
+        // gone, WebLinks should be fixed to use the extension data types.
         for (WebLinkInfoCommon wl :
             webLinks.getFileHistoryLinks(
                 projectName.get(), config.getRevision().getName(), ProjectConfig.PROJECT_CONFIG)) {
           info.configWebLinks.add(new WebLinkInfo(wl.name, wl.imageUrl, wl.url, wl.target));
         }
+      }
 
       if (config.updateGroupNames(groupBackend)) {
         md.setMessage("Update group names\n");

javatests/com/google/gerrit/acceptance/rest/project/AccessIT.java

@@ -52,6 +52,9 @@ import org.eclipse.jgit.internal.storage.dfs.InMemoryRepository;
 import org.eclipse.jgit.junit.TestRepository;
 import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.lib.Constants;
+import org.eclipse.jgit.lib.RefUpdate;
+import org.eclipse.jgit.lib.RefUpdate.Result;
+import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.junit.Before;
 import org.junit.Test;
@@ -83,17 +86,15 @@ public class AccessIT extends AbstractDaemonTest {
   }
 
   @Test
-  public void webLinks() throws Exception {
+  public void webLink() throws Exception {
     RegistrationHandle handle =
         fileHistoryWebLinkDynamicSet.add(
             new FileHistoryWebLink() {
               @Override
               public WebLinkInfo getFileHistoryWebLink(
                   String projectName, String revision, String fileName) {
-                WebLinkInfo info =
+                return new WebLinkInfo(
-                    new WebLinkInfo(
                     "name", "imageURL", "http://view/" + projectName + "/" + fileName);
-                return info;
               }
             });
     try {
@@ -106,6 +107,30 @@ public class AccessIT extends AbstractDaemonTest {
     }
   }
 
+  @Test
+  public void webLinkNoRefsMetaConfig() throws Exception {
+    RegistrationHandle handle =
+        fileHistoryWebLinkDynamicSet.add(
+            new FileHistoryWebLink() {
+              @Override
+              public WebLinkInfo getFileHistoryWebLink(
+                  String projectName, String revision, String fileName) {
+                return new WebLinkInfo(
+                    "name", "imageURL", "http://view/" + projectName + "/" + fileName);
+              }
+            });
+    try (Repository repo = repoManager.openRepository(new Project.NameKey(newProjectName))) {
+      RefUpdate u = repo.updateRef(RefNames.REFS_CONFIG);
+      u.setForceUpdate(true);
+      assertThat(u.delete()).isEqualTo(Result.FORCED);
+
+      // This should not crash.
+      pApi.access();
+    } finally {
+      handle.remove();
+    }
+  }
+
   @Test
   public void addAccessSection() throws Exception {
     Project.NameKey p = new Project.NameKey(newProjectName);