Permit booleans in project.config to be inherited

Allow the parent project to supply the value for properties:

  * use content merge
  * require contributor agreement
  * require change id
  * require signed off by

This makes it easier to configure a large number of projects, as
the properties can be defined once on the parent and inherited.

This commit modifies the default behavior when the variable is not
defined in project.config, it now inherits from the parent rather
than being false.

Change-Id: Ic4a6ea6ff23ad16f1fc82b70cc89a480f59db010

gerrit-server/src/main/java/com/google/gerrit/server/project/ProjectState.java

@@ -14,13 +14,16 @@
 
 package com.google.gerrit.server.project;
 
+import com.google.common.base.Function;
 import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
 import com.google.gerrit.common.data.AccessSection;
 import com.google.gerrit.common.data.GroupReference;
 import com.google.gerrit.common.data.Permission;
 import com.google.gerrit.common.data.PermissionRule;
 import com.google.gerrit.reviewdb.client.AccountGroup;
 import com.google.gerrit.reviewdb.client.Project;
+import com.google.gerrit.reviewdb.client.Project.InheritedBoolean;
 import com.google.gerrit.rules.PrologEnvironment;
 import com.google.gerrit.rules.RulesCache;
 import com.google.gerrit.server.CurrentUser;
@@ -295,4 +298,63 @@ public class ProjectState {
   public boolean isAllProjects() {
     return isAllProjects;
   }
+
+  public boolean isUseContributorAgreements() {
+    return getInheritedBoolean(new Function<Project, InheritedBoolean>() {
+      @Override
+      public InheritedBoolean apply(Project input) {
+        return input.getUseContributorAgreements();
+      }
+    });
+  }
+
+  public boolean isUseContentMerge() {
+    return getInheritedBoolean(new Function<Project, InheritedBoolean>() {
+      @Override
+      public InheritedBoolean apply(Project input) {
+        return input.getUseContentMerge();
+      }
+    });
+  }
+
+  public boolean isUseSignedOffBy() {
+    return getInheritedBoolean(new Function<Project, InheritedBoolean>() {
+      @Override
+      public InheritedBoolean apply(Project input) {
+        return input.getUseSignedOffBy();
+      }
+    });
+  }
+
+  public boolean isRequireChangeID() {
+    return getInheritedBoolean(new Function<Project, InheritedBoolean>() {
+      @Override
+      public InheritedBoolean apply(Project input) {
+        return input.getRequireChangeID();
+      }
+    });
+  }
+
+  private boolean getInheritedBoolean(Function<Project, InheritedBoolean> func) {
+    Set<Project.NameKey> seen = Sets.newHashSet();
+    seen.add(getProject().getNameKey());
+    ProjectState s = this;
+    do {
+      switch (func.apply(s.getProject())) {
+        case TRUE:
+          return true;
+        case FALSE:
+          return false;
+        case INHERIT:
+        default:
+          Project.NameKey parent = s.getProject().getParent(allProjectsName);
+          if (parent != null && seen.add(parent)) {
+            s = projectCache.get(parent);
+          } else {
+            s = null;
+          }
+      }
+    } while (s != null);
+    return false;
+  }
 }