Merge changes Ib5711baa,I730e37bc

* changes:
  Support inheriting project submit type
  Clarify behavior of "default" submit types

Documentation/config-gerrit.txt

@@ -3748,12 +3748,15 @@ Path must be absolute.
 [[repository.name.defaultSubmitType]]repository.<name>.defaultSubmitType::
 +
 The default submit type for newly created projects. Supported values
-are `MERGE_IF_NECESSARY`, `FAST_FORWARD_ONLY`, `REBASE_IF_NECESSARY`,
+are `INHERIT`, `MERGE_IF_NECESSARY`, `FAST_FORWARD_ONLY`, `REBASE_IF_NECESSARY`,
 `REBASE_ALWAYS`, `MERGE_ALWAYS` and `CHERRY_PICK`.
 +
 For more details see link:project-configuration.html#submit_type[Submit Types].
 +
-By default, `MERGE_IF_NECESSARY`.
+This submit type is only applied at project creation time if a submit type is
+omitted from the link:rest-api-projects.html#project-input[ProjectInput]. If the
+submit type is unset in the project config at runtime, it defaults to
+link:project-configuration.html#merge_if_necessary[`MERGE_IF_NECESSARY`].
 
 [[repository.name.ownerGroup]]repository.<name>.ownerGroup::
 +

Documentation/project-configuration.txt

@@ -57,6 +57,12 @@ modified by any project owner through the project console, `Projects` >
 its dependencies are also submitted, with exceptions documented below.
 The following submit types are supported:
 
+[[submit_type_inherit]]
+* Inherit
++
+Inherit the submit type from the parent project. In `All-Projects`, this
+is equivalent to link:#merge_if_necessary[Merge If Necessary].
+
 [[fast_forward_only]]
 * Fast Forward Only
 +
@@ -70,7 +76,8 @@ tip of the destination branch at submit time.
 [[merge_if_necessary]]
 * Merge If Necessary
 +
-This is the default for a new project.
+This is the default for new projects, unless overridden by a global
+link:config-gerrit.html#repository.name.defaultSubmitType[`defaultSubmitType` option].
 +
 If the change being submitted is a strict superset of the destination
 branch, then the branch is fast-forwarded to the change.  If not,

Documentation/rest-api-projects.txt

@@ -494,7 +494,7 @@ link:#project-input[ProjectInput].
 
   {
     "description": "This is a demo project.",
-    "submit_type": "CHERRY_PICK",
+    "submit_type": "INHERIT",
     "owners": [
       "MyProject-Owners"
     ]
@@ -821,7 +821,12 @@ read access to `refs/meta/config`.
       "configured_value": "15m",
       "inherited_value": "20m"
     },
-    "submit_type": "MERGE_IF_NECESSARY",
+    "submit_type": "INHERIT",
+    "default_submit_type": {
+      "value": "MERGE_IF_NECESSARY",
+      "configured_value": "INHERIT",
+      "inherited_value": "MERGE_IF_NECESSARY"
+    },
     "state": "ACTIVE",
     "commentlinks": {},
     "plugin_config": {
@@ -933,6 +938,11 @@ ConfigInfo] entity.
       "inherited_value": "20m"
     },
     "submit_type": "REBASE_IF_NECESSARY",
+    "default_submit_type": {
+      "value": "REBASE_IF_NECESSARY",
+      "configured_value": "INHERIT",
+      "inherited_value": "REBASE_IF_NECESSARY"
+    },
     "state": "ACTIVE",
     "commentlinks": {}
   }
@@ -2846,10 +2856,12 @@ all new changes are set as private by default.
 The link:config-gerrit.html#receive.maxObjectSizeLimit[max object size
 limit] of this project as a link:#max-object-size-limit-info[
 MaxObjectSizeLimitInfo] entity.
+|`default_submit_type`     ||
+link:#submit-type-info[SubmitTypeInfo] that describes the default submit type of
+the project, when not overridden at the change level.
 |`submit_type`               ||
-The default submit type of the project, can be `MERGE_IF_NECESSARY`,
+Deprecated; equivalent to link:#submit-type-info[`value`] in
-`FAST_FORWARD_ONLY`, `REBASE_IF_NECESSARY`, `REBASE_ALWAYS`, `MERGE_ALWAYS` or
+`default_submit_type`.
-`CHERRY_PICK`.
 |`match_author_to_committer_date` |optional|
 link:#inherited-boolean-info[InheritedBooleanInfo] that indicates whether
 a change's author date will be changed to match its submitter date upon submit.
@@ -3327,6 +3339,27 @@ statistics of a Git repository.
 |`size_of_packed_objects`  |Size of packed objects in bytes.
 |======================================
 
+[[submit-type-info]]
+=== SubmitTypeInfo
+Information about the link:project-configuration.html#submit_type[default submit
+type of a project], taking into account project inheritance.
+
+Valid values for each field are `MERGE_IF_NECESSARY`, `FAST_FORWARD_ONLY`,
+`REBASE_IF_NECESSARY`, `REBASE_ALWAYS`, `MERGE_ALWAYS` or `CHERRY_PICK`, plus
+`INHERIT` where applicable.
+
+[options="header",cols="1,6"]
+|===============================
+|Field Name         |Description
+|`value`            |
+The effective submit type value. Never `INHERIT`.
+|`configured_value` |
+The configured value, can be one of the submit types, or `INHERIT` to inherit
+from the parent project.
+|`inherited_value`  |
+The effective value that would be inherited from the parent. Never `INHERIT`.
+|===============================
+
 [[tag-info]]
 === TagInfo
 The `TagInfo` entity contains information about a tag.

gerrit-gwtui/src/main/java/com/google/gerrit/client/admin/AdminConstants.java

@@ -133,6 +133,8 @@ public interface AdminConstants extends Constants {
 
   String headingProjectSubmitType();
 
+  String projectSubmitType_INHERIT();
+
   String projectSubmitType_FAST_FORWARD_ONLY();
 
   String projectSubmitType_MERGE_ALWAYS();

gerrit-gwtui/src/main/java/com/google/gerrit/client/admin/AdminConstants.properties

@@ -57,6 +57,7 @@ headingAgreements = Contributor Agreements
 headingAuditLog = Audit Log
 
 headingProjectSubmitType = Submit Type
+projectSubmitType_INHERIT = Inherit
 projectSubmitType_FAST_FORWARD_ONLY = Fast Forward Only
 projectSubmitType_MERGE_IF_NECESSARY = Merge if Necessary
 projectSubmitType_REBASE_ALWAYS = Rebase Always

gerrit-gwtui/src/main/java/com/google/gerrit/client/admin/ProjectInfoScreen.java

@@ -30,6 +30,7 @@ import com.google.gerrit.client.projects.ConfigInfo;
 import com.google.gerrit.client.projects.ConfigInfo.ConfigParameterInfo;
 import com.google.gerrit.client.projects.ConfigInfo.ConfigParameterValue;
 import com.google.gerrit.client.projects.ConfigInfo.InheritedBooleanInfo;
+import com.google.gerrit.client.projects.ConfigInfo.SubmitTypeInfo;
 import com.google.gerrit.client.projects.ProjectApi;
 import com.google.gerrit.client.rpc.CallbackGroup;
 import com.google.gerrit.client.rpc.GerritCallback;
@@ -335,13 +336,15 @@ public class ProjectInfoScreen extends ProjectScreen {
     grid.addHtml(AdminConstants.I.useSignedOffBy(), signedOffBy);
   }
 
-  private void setSubmitType(SubmitType newSubmitType) {
+  private void setSubmitType(SubmitTypeInfo newSubmitType) {
     int index = -1;
-    if (submitType != null) {
+    if (newSubmitType != null) {
       for (int i = 0; i < submitType.getItemCount(); i++) {
-        if (newSubmitType.name().equals(submitType.getValue(i))) {
+        if (submitType.getValue(i).equals(SubmitType.INHERIT.name())) {
+          submitType.setItemText(i, getInheritString(newSubmitType));
+        }
+        if (newSubmitType.configuredValue().name().equals(submitType.getValue(i))) {
           index = i;
-          break;
         }
       }
       submitType.setSelectedIndex(index);
@@ -349,6 +352,13 @@ public class ProjectInfoScreen extends ProjectScreen {
     }
   }
 
+  private static String getInheritString(SubmitTypeInfo submitType) {
+    return Util.toLongString(SubmitType.INHERIT)
+        + " ("
+        + Util.toLongString(submitType.inheritedValue())
+        + ")";
+  }
+
   private void setState(ProjectState newState) {
     if (state != null) {
       for (int i = 0; i < state.getItemCount(); i++) {
@@ -419,7 +429,7 @@ public class ProjectInfoScreen extends ProjectScreen {
     setBool(privateByDefault, result.privateByDefault());
     setBool(enableReviewerByEmail, result.enableReviewerByEmail());
     setBool(matchAuthorToCommitterDate, result.matchAuthorToCommitterDate());
-    setSubmitType(result.submitType());
+    setSubmitType(result.defaultSubmitType());
     setState(result.state());
     maxObjectSizeLimit.setText(result.maxObjectSizeLimit().configuredValue());
     if (result.maxObjectSizeLimit().inheritedValue() != null) {

gerrit-gwtui/src/main/java/com/google/gerrit/client/admin/Util.java

@@ -35,6 +35,8 @@ public class Util {
       return "";
     }
     switch (type) {
+      case INHERIT:
+        return AdminConstants.I.projectSubmitType_INHERIT();
       case FAST_FORWARD_ONLY:
         return AdminConstants.I.projectSubmitType_FAST_FORWARD_ONLY();
       case MERGE_IF_NECESSARY:

gerrit-gwtui/src/main/java/com/google/gerrit/client/projects/ConfigInfo.java

@@ -70,6 +70,8 @@ public class ConfigInfo extends JavaScriptObject {
     return SubmitType.valueOf(submitTypeRaw());
   }
 
+  public final native SubmitTypeInfo defaultSubmitType() /*-{ return this.default_submit_type; }-*/;
+
   public final native NativeMap<NativeMap<ConfigParameterInfo>> pluginConfig()
       /*-{ return this.plugin_config || {}; }-*/ ;
 
@@ -232,4 +234,26 @@ public class ConfigInfo extends JavaScriptObject {
 
     protected ConfigParameterValue() {}
   }
+
+  public static class SubmitTypeInfo extends JavaScriptObject {
+    public final SubmitType value() {
+      return SubmitType.valueOf(valueRaw());
+    }
+
+    public final SubmitType configuredValue() {
+      return SubmitType.valueOf(configuredValueRaw());
+    }
+
+    public final SubmitType inheritedValue() {
+      return SubmitType.valueOf(inheritedValueRaw());
+    }
+
+    private final native String valueRaw() /*-{ return this.value; }-*/;
+
+    private final native String configuredValueRaw() /*-{ return this.configured_value; }-*/;
+
+    private final native String inheritedValueRaw() /*-{ return this.inherited_value; }-*/;
+
+    protected SubmitTypeInfo() {}
+  }
 }

gerrit-gwtui/src/main/java/com/google/gerrit/client/projects/ProjectApi.java

@@ -176,7 +176,9 @@ public class ProjectApi {
     in.setRejectImplicitMerges(rejectImplicitMerges);
     in.setPrivateByDefault(privateByDefault);
     in.setMaxObjectSizeLimit(maxObjectSizeLimit);
-    in.setSubmitType(submitType);
+    if (submitType != null) {
+      in.setSubmitType(submitType);
+    }
     in.setState(state);
     in.setPluginConfigValues(pluginConfigValues);
     in.setEnableReviewerByEmail(enableReviewerByEmail);

java/com/google/gerrit/common/data/SubmitTypeRecord.java

@@ -48,6 +48,9 @@ public class SubmitTypeRecord {
   public final String errorMessage;
 
   private SubmitTypeRecord(Status status, SubmitType type, String errorMessage) {
+    if (type == SubmitType.INHERIT) {
+      throw new IllegalArgumentException("Cannot output submit type " + type);
+    }
     this.status = status;
     this.type = type;
     this.errorMessage = errorMessage;

java/com/google/gerrit/extensions/api/projects/ConfigInfo.java

@@ -38,7 +38,9 @@ public class ConfigInfo {
   public InheritedBooleanInfo rejectEmptyCommit;
 
   public MaxObjectSizeLimitInfo maxObjectSizeLimit;
+  @Deprecated // Equivalent to defaultSubmitType.value
   public SubmitType submitType;
+  public SubmitTypeInfo defaultSubmitType;
   public ProjectState state;
   public Map<String, Map<String, ConfigParameterInfo>> pluginConfig;
   public Map<String, ActionInfo> actions;
@@ -73,4 +75,10 @@ public class ConfigInfo {
     public List<String> permittedValues;
     public List<String> values;
   }
+
+  public static class SubmitTypeInfo {
+    public SubmitType value;
+    public SubmitType configuredValue;
+    public SubmitType inheritedValue;
+  }
 }

java/com/google/gerrit/extensions/client/SubmitType.java

@@ -15,10 +15,11 @@
 package com.google.gerrit.extensions.client;
 
 public enum SubmitType {
+  INHERIT,
   FAST_FORWARD_ONLY,
   MERGE_IF_NECESSARY,
   REBASE_IF_NECESSARY,
   REBASE_ALWAYS,
   MERGE_ALWAYS,
-  CHERRY_PICK
+  CHERRY_PICK;
 }

java/com/google/gerrit/reviewdb/client/Project.java

@@ -25,6 +25,12 @@ import java.util.Map;
 
 /** Projects match a source code repository managed by Gerrit */
 public final class Project {
+  /** Default submit type for new projects. */
+  public static final SubmitType DEFAULT_SUBMIT_TYPE = SubmitType.MERGE_IF_NECESSARY;
+
+  /** Default submit type for root project (All-Projects). */
+  public static final SubmitType DEFAULT_ALL_PROJECTS_SUBMIT_TYPE = SubmitType.MERGE_IF_NECESSARY;
+
   /** Project name key */
   public static class NameKey extends StringKey<com.google.gwtorm.client.Key<?>> {
     private static final long serialVersionUID = 1L;
@@ -137,7 +143,14 @@ public final class Project {
     maxObjectSizeLimit = limit;
   }
 
-  public SubmitType getSubmitType() {
+  /**
+   * Submit type as configured in {@code project.config}.
+   *
+   * <p>Does not take inheritance into account, i.e. may return {@link SubmitType#INHERIT}.
+   *
+   * @return submit type.
+   */
+  public SubmitType getConfiguredSubmitType() {
     return submitType;
   }
 

java/com/google/gerrit/server/change/MergeabilityCacheImpl.java

@@ -14,6 +14,7 @@
 
 package com.google.gerrit.server.change;
 
+import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkState;
 import static com.google.gerrit.server.ioutil.BasicSerialization.readString;
@@ -59,6 +60,7 @@ public class MergeabilityCacheImpl implements MergeabilityCache {
 
   public static final ImmutableBiMap<SubmitType, Character> SUBMIT_TYPES =
       new ImmutableBiMap.Builder<SubmitType, Character>()
+          .put(SubmitType.INHERIT, 'I')
           .put(SubmitType.FAST_FORWARD_ONLY, 'F')
           .put(SubmitType.MERGE_IF_NECESSARY, 'M')
           .put(SubmitType.REBASE_ALWAYS, 'P')
@@ -98,6 +100,11 @@ public class MergeabilityCacheImpl implements MergeabilityCache {
     private String mergeStrategy;
 
     public EntryKey(ObjectId commit, ObjectId into, SubmitType submitType, String mergeStrategy) {
+      checkArgument(
+          submitType != SubmitType.INHERIT,
+          "Cannot cache %s.%s",
+          SubmitType.class.getSimpleName(),
+          submitType);
       this.commit = checkNotNull(commit, "commit");
       this.into = checkNotNull(into, "into");
       this.submitType = checkNotNull(submitType, "submitType");

java/com/google/gerrit/server/git/ProjectConfig.java

@@ -16,6 +16,7 @@ package com.google.gerrit.server.git;
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.gerrit.common.data.Permission.isPermission;
+import static com.google.gerrit.reviewdb.client.Project.DEFAULT_SUBMIT_TYPE;
 
 import com.google.common.base.CharMatcher;
 import com.google.common.base.Joiner;
@@ -42,7 +43,6 @@ import com.google.gerrit.common.data.SubscribeSection;
 import com.google.gerrit.common.errors.InvalidNameException;
 import com.google.gerrit.extensions.client.InheritableBoolean;
 import com.google.gerrit.extensions.client.ProjectState;
-import com.google.gerrit.extensions.client.SubmitType;
 import com.google.gerrit.reviewdb.client.AccountGroup;
 import com.google.gerrit.reviewdb.client.BooleanProjectConfig;
 import com.google.gerrit.reviewdb.client.Branch;
@@ -151,7 +151,6 @@ public class ProjectConfig extends VersionedMetaData implements ValidationError.
 
   private static final String PLUGIN = "plugin";
 
-  private static final SubmitType DEFAULT_SUBMIT_ACTION = SubmitType.MERGE_IF_NECESSARY;
   private static final ProjectState DEFAULT_STATE_VALUE = ProjectState.ACTIVE;
 
   private static final String EXTENSION_PANELS = "extension-panels";
@@ -519,7 +518,7 @@ public class ProjectConfig extends VersionedMetaData implements ValidationError.
 
     p.setMaxObjectSizeLimit(rc.getString(RECEIVE, null, KEY_MAX_OBJECT_SIZE_LIMIT));
 
-    p.setSubmitType(getEnum(rc, SUBMIT, null, KEY_ACTION, DEFAULT_SUBMIT_ACTION));
+    p.setSubmitType(getEnum(rc, SUBMIT, null, KEY_ACTION, DEFAULT_SUBMIT_TYPE));
     p.setState(getEnum(rc, PROJECT, null, KEY_STATE, DEFAULT_STATE_VALUE));
 
     p.setDefaultDashboard(rc.getString(DASHBOARD, null, KEY_DEFAULT));
@@ -1043,7 +1042,7 @@ public class ProjectConfig extends VersionedMetaData implements ValidationError.
         KEY_MAX_OBJECT_SIZE_LIMIT,
         validMaxObjectSizeLimit(p.getMaxObjectSizeLimit()));
 
-    set(rc, SUBMIT, null, KEY_ACTION, p.getSubmitType(), DEFAULT_SUBMIT_ACTION);
+    set(rc, SUBMIT, null, KEY_ACTION, p.getConfiguredSubmitType(), DEFAULT_SUBMIT_TYPE);
 
     set(rc, PROJECT, null, KEY_STATE, p.getState(), DEFAULT_STATE_VALUE);
 

java/com/google/gerrit/server/git/strategy/SubmitDryRun.java

@@ -133,6 +133,7 @@ public class SubmitDryRun {
         return RebaseIfNecessary.dryRun(args, repo, tipCommit, toMergeCommit);
       case REBASE_ALWAYS:
         return RebaseAlways.dryRun(args, repo, tipCommit, toMergeCommit);
+      case INHERIT:
       default:
         String errorMsg = "No submit strategy for: " + submitType;
         log.error(errorMsg);

java/com/google/gerrit/server/git/strategy/SubmitStrategyFactory.java

@@ -96,6 +96,7 @@ public class SubmitStrategyFactory {
         return new RebaseIfNecessary(args);
       case REBASE_ALWAYS:
         return new RebaseAlways(args);
+      case INHERIT:
       default:
         String errorMsg = "No submit strategy for: " + submitType;
         log.error(errorMsg);

java/com/google/gerrit/server/git/strategy/SubmitStrategyOp.java

@@ -465,6 +465,7 @@ abstract class SubmitStrategyOp implements BatchUpdateOp {
         case REBASE_IF_NECESSARY:
         case REBASE_ALWAYS:
           return message(ctx, commit, CommitMergeStatus.CLEAN_REBASE);
+        case INHERIT:
         default:
           throw new IllegalStateException(
               "unexpected submit type "

java/com/google/gerrit/server/project/ProjectState.java

@@ -31,6 +31,7 @@ import com.google.gerrit.common.data.RefConfigSection;
 import com.google.gerrit.common.data.SubscribeSection;
 import com.google.gerrit.extensions.api.projects.CommentLinkInfo;
 import com.google.gerrit.extensions.api.projects.ThemeInfo;
+import com.google.gerrit.extensions.client.SubmitType;
 import com.google.gerrit.reviewdb.client.AccountGroup;
 import com.google.gerrit.reviewdb.client.BooleanProjectConfig;
 import com.google.gerrit.reviewdb.client.Branch;
@@ -490,6 +491,16 @@ public class ProjectState {
     return getGroups(getLocalAccessSections());
   }
 
+  public SubmitType getSubmitType() {
+    for (ProjectState s : tree()) {
+      SubmitType t = s.getProject().getConfiguredSubmitType();
+      if (t != SubmitType.INHERIT) {
+        return t;
+      }
+    }
+    return Project.DEFAULT_ALL_PROJECTS_SUBMIT_TYPE;
+  }
+
   private static Set<GroupReference> getGroups(List<SectionMatcher> sectionMatcherList) {
     final Set<GroupReference> all = new HashSet<>();
     for (SectionMatcher matcher : sectionMatcherList) {

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

@@ -14,6 +14,7 @@
 
 package com.google.gerrit.server.restapi.project;
 
+import com.google.common.base.MoreObjects;
 import com.google.common.base.Strings;
 import com.google.common.collect.Iterables;
 import com.google.gerrit.extensions.api.projects.CommentLinkInfo;
@@ -42,6 +43,7 @@ import java.util.Map;
 import java.util.TreeMap;
 
 public class ConfigInfoImpl extends ConfigInfo {
+  @SuppressWarnings("deprecation")
   public ConfigInfoImpl(
       boolean serverEnableSignedPush,
       ProjectState projectState,
@@ -79,7 +81,18 @@ public class ConfigInfoImpl extends ConfigInfo {
     maxObjectSizeLimit.inheritedValue = config.getFormattedMaxObjectSizeLimit();
     this.maxObjectSizeLimit = maxObjectSizeLimit;
 
-    this.submitType = p.getSubmitType();
+    this.defaultSubmitType = new SubmitTypeInfo();
+    this.defaultSubmitType.value = projectState.getSubmitType();
+    this.defaultSubmitType.configuredValue =
+        MoreObjects.firstNonNull(
+            projectState.getConfig().getProject().getConfiguredSubmitType(),
+            Project.DEFAULT_SUBMIT_TYPE);
+    ProjectState parent =
+        projectState.isAllProjects() ? projectState : projectState.parents().get(0);
+    this.defaultSubmitType.inheritedValue = parent.getSubmitType();
+
+    this.submitType = this.defaultSubmitType.value;
+
     this.state =
         p.getState() != com.google.gerrit.extensions.client.ProjectState.ACTIVE
             ? p.getState()

java/gerrit/PRED_project_default_submit_type_1.java

@@ -47,7 +47,7 @@ public class PRED_project_default_submit_type_1 extends Predicate.P1 {
     Term a1 = arg1.dereference();
 
     ProjectState projectState = StoredValues.PROJECT_STATE.get(engine);
-    SubmitType submitType = projectState.getProject().getSubmitType();
+    SubmitType submitType = projectState.getSubmitType();
     if (!a1.unify(term[submitType.ordinal()], engine.trail)) {
       return engine.fail();
     }

javatests/com/google/gerrit/acceptance/api/project/ProjectIT.java

@@ -219,13 +219,13 @@ public class ProjectIT extends AbstractDaemonTest {
     RevCommit initialHead = getRemoteHead(project, RefNames.REFS_CONFIG);
 
     ConfigInfo info = gApi.projects().name(project.get()).config();
-    assertThat(info.submitType).isEqualTo(SubmitType.MERGE_IF_NECESSARY);
+    assertThat(info.defaultSubmitType.value).isEqualTo(SubmitType.MERGE_IF_NECESSARY);
     ConfigInput input = new ConfigInput();
     input.submitType = SubmitType.CHERRY_PICK;
     info = gApi.projects().name(project.get()).config(input);
-    assertThat(info.submitType).isEqualTo(SubmitType.CHERRY_PICK);
+    assertThat(info.defaultSubmitType.value).isEqualTo(SubmitType.CHERRY_PICK);
     info = gApi.projects().name(project.get()).config();
-    assertThat(info.submitType).isEqualTo(SubmitType.CHERRY_PICK);
+    assertThat(info.defaultSubmitType.value).isEqualTo(SubmitType.CHERRY_PICK);
 
     RevCommit updatedHead = getRemoteHead(project, RefNames.REFS_CONFIG);
     eventRecorder.assertRefUpdatedEvents(
@@ -233,6 +233,7 @@ public class ProjectIT extends AbstractDaemonTest {
   }
 
   @Test
+  @SuppressWarnings("deprecation")
   public void setConfig() throws Exception {
     ConfigInput input = createTestConfigInput();
     ConfigInfo info = gApi.projects().name(project.get()).config(input);
@@ -250,9 +251,13 @@ public class ProjectIT extends AbstractDaemonTest {
         .isEqualTo(input.createNewChangeForAllNotInTarget);
     assertThat(info.maxObjectSizeLimit.configuredValue).isEqualTo(input.maxObjectSizeLimit);
     assertThat(info.submitType).isEqualTo(input.submitType);
+    assertThat(info.defaultSubmitType.value).isEqualTo(input.submitType);
+    assertThat(info.defaultSubmitType.inheritedValue).isEqualTo(SubmitType.MERGE_IF_NECESSARY);
+    assertThat(info.defaultSubmitType.configuredValue).isEqualTo(input.submitType);
     assertThat(info.state).isEqualTo(input.state);
   }
 
+  @SuppressWarnings("deprecation")
   @Test
   public void setPartialConfig() throws Exception {
     ConfigInput input = createTestConfigInput();
@@ -276,6 +281,9 @@ public class ProjectIT extends AbstractDaemonTest {
         .isEqualTo(input.createNewChangeForAllNotInTarget);
     assertThat(info.maxObjectSizeLimit.configuredValue).isEqualTo(input.maxObjectSizeLimit);
     assertThat(info.submitType).isEqualTo(input.submitType);
+    assertThat(info.defaultSubmitType.value).isEqualTo(input.submitType);
+    assertThat(info.defaultSubmitType.inheritedValue).isEqualTo(SubmitType.MERGE_IF_NECESSARY);
+    assertThat(info.defaultSubmitType.configuredValue).isEqualTo(input.submitType);
     assertThat(info.state).isEqualTo(input.state);
   }
 

javatests/com/google/gerrit/acceptance/rest/change/AbstractSubmit.java

@@ -238,6 +238,7 @@ public abstract class AbstractSubmit extends AbstractDaemonTest {
           break;
         case MERGE_ALWAYS:
         case MERGE_IF_NECESSARY:
+        case INHERIT:
           assertThat(e.getMessage())
               .isEqualTo(
                   "Failed to submit 3 changes due to the following problems:\n"

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

@@ -24,9 +24,12 @@ import com.google.common.collect.Lists;
 import com.google.common.collect.Sets;
 import com.google.common.net.HttpHeaders;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
+import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.RestResponse;
 import com.google.gerrit.acceptance.UseLocalDisk;
 import com.google.gerrit.common.data.GlobalCapability;
+import com.google.gerrit.extensions.api.projects.ConfigInfo;
+import com.google.gerrit.extensions.api.projects.ConfigInput;
 import com.google.gerrit.extensions.api.projects.ProjectInput;
 import com.google.gerrit.extensions.client.InheritableBoolean;
 import com.google.gerrit.extensions.client.SubmitType;
@@ -181,7 +184,7 @@ public class CreateProjectIT extends AbstractDaemonTest {
     Project project = projectCache.get(new Project.NameKey(newProjectName)).getProject();
     assertProjectInfo(project, p);
     assertThat(project.getDescription()).isEqualTo(in.description);
-    assertThat(project.getSubmitType()).isEqualTo(in.submitType);
+    assertThat(project.getConfiguredSubmitType()).isEqualTo(in.submitType);
     assertThat(project.getBooleanConfig(BooleanProjectConfig.USE_CONTRIBUTOR_AGREEMENTS))
         .isEqualTo(in.useContributorAgreements);
     assertThat(project.getBooleanConfig(BooleanProjectConfig.USE_SIGNED_OFF_BY))
@@ -331,6 +334,84 @@ public class CreateProjectIT extends AbstractDaemonTest {
     }
   }
 
+  @SuppressWarnings("deprecation")
+  @Test
+  public void createProjectWithDefaultInheritedSubmitType() throws Exception {
+    String parent = name("parent");
+    ProjectInput pin = new ProjectInput();
+    pin.name = parent;
+    ConfigInfo cfg = gApi.projects().create(pin).config();
+    assertThat(cfg.submitType).isEqualTo(SubmitType.MERGE_IF_NECESSARY);
+    assertThat(cfg.defaultSubmitType.value).isEqualTo(SubmitType.MERGE_IF_NECESSARY);
+    assertThat(cfg.defaultSubmitType.configuredValue).isEqualTo(SubmitType.MERGE_IF_NECESSARY);
+    assertThat(cfg.defaultSubmitType.inheritedValue).isEqualTo(SubmitType.MERGE_IF_NECESSARY);
+
+    ConfigInput cin = new ConfigInput();
+    cin.submitType = SubmitType.CHERRY_PICK;
+    gApi.projects().name(parent).config(cin);
+    cfg = gApi.projects().name(parent).config();
+    assertThat(cfg.submitType).isEqualTo(SubmitType.CHERRY_PICK);
+    assertThat(cfg.defaultSubmitType.value).isEqualTo(SubmitType.CHERRY_PICK);
+    assertThat(cfg.defaultSubmitType.configuredValue).isEqualTo(SubmitType.CHERRY_PICK);
+    assertThat(cfg.defaultSubmitType.inheritedValue).isEqualTo(SubmitType.MERGE_IF_NECESSARY);
+
+    String child = name("child");
+    pin = new ProjectInput();
+    pin.submitType = SubmitType.INHERIT;
+    pin.parent = parent;
+    pin.name = child;
+    cfg = gApi.projects().create(pin).config();
+    assertThat(cfg.submitType).isEqualTo(SubmitType.CHERRY_PICK);
+    assertThat(cfg.defaultSubmitType.value).isEqualTo(SubmitType.CHERRY_PICK);
+    assertThat(cfg.defaultSubmitType.configuredValue).isEqualTo(SubmitType.INHERIT);
+    assertThat(cfg.defaultSubmitType.inheritedValue).isEqualTo(SubmitType.CHERRY_PICK);
+
+    cin = new ConfigInput();
+    cin.submitType = SubmitType.REBASE_IF_NECESSARY;
+    gApi.projects().name(parent).config(cin);
+    cfg = gApi.projects().name(parent).config();
+    assertThat(cfg.submitType).isEqualTo(SubmitType.REBASE_IF_NECESSARY);
+    assertThat(cfg.defaultSubmitType.value).isEqualTo(SubmitType.REBASE_IF_NECESSARY);
+    assertThat(cfg.defaultSubmitType.configuredValue).isEqualTo(SubmitType.REBASE_IF_NECESSARY);
+    assertThat(cfg.defaultSubmitType.inheritedValue).isEqualTo(SubmitType.MERGE_IF_NECESSARY);
+
+    cfg = gApi.projects().name(child).config();
+    assertThat(cfg.submitType).isEqualTo(SubmitType.REBASE_IF_NECESSARY);
+    assertThat(cfg.defaultSubmitType.value).isEqualTo(SubmitType.REBASE_IF_NECESSARY);
+    assertThat(cfg.defaultSubmitType.configuredValue).isEqualTo(SubmitType.INHERIT);
+    assertThat(cfg.defaultSubmitType.inheritedValue).isEqualTo(SubmitType.REBASE_IF_NECESSARY);
+  }
+
+  @SuppressWarnings("deprecation")
+  @Test
+  @GerritConfig(
+    name = "repository.testinheritedsubmittype/*.defaultSubmitType",
+    value = "CHERRY_PICK"
+  )
+  public void repositoryConfigTakesPrecedenceOverInheritedSubmitType() throws Exception {
+    // Can't use name() since we need to specify this project name in gerrit.config prior to
+    // startup. Pick something reasonably unique instead.
+    String parent = "testinheritedsubmittype";
+    ProjectInput pin = new ProjectInput();
+    pin.name = parent;
+    pin.submitType = SubmitType.MERGE_ALWAYS;
+    ConfigInfo cfg = gApi.projects().create(pin).config();
+    assertThat(cfg.submitType).isEqualTo(SubmitType.MERGE_ALWAYS);
+    assertThat(cfg.defaultSubmitType.value).isEqualTo(SubmitType.MERGE_ALWAYS);
+    assertThat(cfg.defaultSubmitType.configuredValue).isEqualTo(SubmitType.MERGE_ALWAYS);
+    assertThat(cfg.defaultSubmitType.inheritedValue).isEqualTo(SubmitType.MERGE_IF_NECESSARY);
+
+    String child = parent + "/child";
+    pin = new ProjectInput();
+    pin.parent = parent;
+    pin.name = child;
+    cfg = gApi.projects().create(pin).config();
+    assertThat(cfg.submitType).isEqualTo(SubmitType.CHERRY_PICK);
+    assertThat(cfg.defaultSubmitType.value).isEqualTo(SubmitType.CHERRY_PICK);
+    assertThat(cfg.defaultSubmitType.configuredValue).isEqualTo(SubmitType.CHERRY_PICK);
+    assertThat(cfg.defaultSubmitType.inheritedValue).isEqualTo(SubmitType.MERGE_ALWAYS);
+  }
+
   private void assertHead(String projectName, String expectedRef) throws Exception {
     try (Repository repo = repoManager.openRepository(new Project.NameKey(projectName))) {
       assertThat(repo.exactRef(Constants.HEAD).getTarget().getName()).isEqualTo(expectedRef);

polygerrit-ui/app/elements/admin/gr-repo/gr-repo.html

@@ -103,7 +103,8 @@ limitations under the License.
                       id="submitTypeSelect"
                       bind-value="{{_repoConfig.submit_type}}">
                     <select disabled$="[[_readOnly]]">
-                      <template is="dom-repeat" items="[[_submitTypes]]">
+                      <template is="dom-repeat"
+                          items="[[_formatSubmitTypeSelect(_repoConfig)]]">
                         <option value="[[item.value]]">[[item.label]]</option>
                       </template>
                     </select>

polygerrit-ui/app/elements/admin/gr-repo/gr-repo.js

@@ -21,6 +21,7 @@
   };
 
   const SUBMIT_TYPES = {
+    // Exclude INHERIT, which is handled specially.
     mergeIfNecessary: {
       value: 'MERGE_IF_NECESSARY',
       label: 'Merge if necessary',
@@ -129,6 +130,15 @@
 
       promises.push(this.$.restAPI.getProjectConfig(this.repo).then(
           config => {
+            if (config.default_submit_type) {
+              // The gr-select is bound to submit_type, which needs to be the
+              // *configured* submit type. When default_submit_type is
+              // present, the server reports the *effective* submit type in
+              // submit_type, so we need to overwrite it before storing the
+              // config in this.
+              config.submit_type =
+                  config.default_submit_type.configured_value;
+            }
             if (!config.state) {
               config.state = STATES.active.value;
             }
@@ -183,6 +193,36 @@
       ];
     },
 
+    _formatSubmitTypeSelect(projectConfig) {
+      if (!projectConfig) { return; }
+      const allValues = Object.values(SUBMIT_TYPES);
+      const type = projectConfig.default_submit_type;
+      if (!type) {
+        // Server is too old to report default_submit_type, so assume INHERIT
+        // is not a valid value.
+        return allValues;
+      }
+
+      let inheritLabel = 'Inherit';
+      if (type.inherited_value) {
+        let inherited = type.inherited_value;
+        for (const val of allValues) {
+          if (val.value === type.inherited_value) {
+            inherited = val.label;
+            break;
+          }
+        }
+        inheritLabel = `Inherit (${inherited})`;
+      }
+      return [
+        {
+          label: inheritLabel,
+          value: 'INHERIT',
+        },
+        ...allValues,
+      ];
+    },
+
     _isLoading() {
       return this._loading || this._loading === undefined;
     },
@@ -195,6 +235,12 @@
       const configInputObj = {};
       for (const key in p) {
         if (p.hasOwnProperty(key)) {
+          if (key === 'default_submit_type') {
+            // default_submit_type is not in the input type, and the
+            // configured value was already copied to submit_type by
+            // _loadProject. Omit this property when saving.
+            continue;
+          }
           if (typeof p[key] === 'object') {
             configInputObj[key] = p[key].configured_value;
           } else {

polygerrit-ui/app/elements/admin/gr-repo/gr-repo_test.html

@@ -99,6 +99,11 @@ limitations under the License.
             },
             max_object_size_limit: {},
             submit_type: 'MERGE_IF_NECESSARY',
+            default_submit_type: {
+              value: 'MERGE_IF_NECESSARY',
+              configured_value: 'INHERIT',
+              inherited_value: 'MERGE_IF_NECESSARY',
+            },
           });
         },
         getConfig() {
@@ -252,7 +257,16 @@ limitations under the License.
         });
       });
 
-      test('fields update and save correctly', done => {
+      test('inherited submit type value is calculated correctly', () => {
+        return element._loadRepo().then(() => {
+          const sel = element.$.submitTypeSelect;
+          assert.equal(sel.bindValue, 'INHERIT');
+          assert.equal(
+              sel.nativeSelect.options[0].text, 'Inherit (Merge if necessary)');
+        });
+      });
+
+      test('fields update and save correctly', () => {
         // test notedb
         element._noteDbEnabled = false;
 
@@ -289,7 +303,7 @@ limitations under the License.
 
         const button = Polymer.dom(element.root).querySelector('gr-button');
 
-        element._loadRepo().then(() => {
+        return element._loadRepo().then(() => {
           assert.isTrue(button.hasAttribute('disabled'));
           assert.isFalse(element.$.Title.classList.contains('edited'));
           element.$.descriptionInput.bindValue = configInputObj.description;
@@ -327,12 +341,11 @@ limitations under the License.
               element._formatRepoConfigForSave(element._repoConfig);
           assert.deepEqual(formattedObj, configInputObj);
 
-          element._handleSaveRepoConfig().then(() => {
+          return element._handleSaveRepoConfig().then(() => {
             assert.isTrue(button.hasAttribute('disabled'));
             assert.isFalse(element.$.Title.classList.contains('edited'));
             assert.isTrue(saveStub.lastCall.calledWithExactly(REPO,
                 configInputObj));
-            done();
           });
         });
       });