Merge changes from topic "boolcond"

* changes:
  UiActions: defer GlobalPermission checks on views
  CherryPick: use BooleanCondition for visible
  PermissionBackend: support bulk evaluation of UiAction
  PermissionBackend: support testCond for UiAction
  Delay UiAction visible and enabled with BooleanCondition

gerrit-extension-api/src/main/java/com/google/gerrit/extensions/conditions/BooleanCondition.java

@@ -0,0 +1,217 @@
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.extensions.conditions;
+
+import com.google.common.collect.Iterables;
+import java.util.Collections;
+
+/** Delayed evaluation of a boolean condition. */
+public abstract class BooleanCondition {
+  public static final BooleanCondition TRUE = new Value(true);
+  public static final BooleanCondition FALSE = new Value(false);
+
+  public static BooleanCondition valueOf(boolean a) {
+    return a ? TRUE : FALSE;
+  }
+
+  public static BooleanCondition and(BooleanCondition a, BooleanCondition b) {
+    return a == FALSE || b == FALSE ? FALSE : new And(a, b);
+  }
+
+  public static BooleanCondition and(boolean a, BooleanCondition b) {
+    return and(valueOf(a), b);
+  }
+
+  public static BooleanCondition or(BooleanCondition a, BooleanCondition b) {
+    return a == TRUE || b == TRUE ? TRUE : new Or(a, b);
+  }
+
+  public static BooleanCondition or(boolean a, BooleanCondition b) {
+    return or(valueOf(a), b);
+  }
+
+  public static BooleanCondition not(BooleanCondition bc) {
+    return bc == TRUE ? FALSE : bc == FALSE ? TRUE : new Not(bc);
+  }
+
+  BooleanCondition() {}
+
+  /** @return evaluate the condition and return its value. */
+  public abstract boolean value();
+
+  /**
+   * Recursively collect all children of type {@code type}.
+   *
+   * @param type implementation type of the conditions to collect and return.
+   * @return non-null, unmodifiable iteration of children of type {@code type}.
+   */
+  public abstract <T> Iterable<T> children(Class<T> type);
+
+  private static final class And extends BooleanCondition {
+    private final BooleanCondition a;
+    private final BooleanCondition b;
+
+    And(BooleanCondition a, BooleanCondition b) {
+      this.a = a;
+      this.b = b;
+    }
+
+    @Override
+    public boolean value() {
+      return a.value() && b.value();
+    }
+
+    @Override
+    public <T> Iterable<T> children(Class<T> type) {
+      return Iterables.concat(a.children(type), b.children(type));
+    }
+
+    @Override
+    public int hashCode() {
+      return a.hashCode() * 31 + b.hashCode();
+    }
+
+    @Override
+    public boolean equals(Object other) {
+      if (other instanceof And) {
+        And o = (And) other;
+        return a.equals(o.a) && b.equals(o.b);
+      }
+      return false;
+    }
+
+    @Override
+    public String toString() {
+      return "(" + maybeTrim(a, getClass()) + " && " + maybeTrim(a, getClass()) + ")";
+    }
+  }
+
+  private static final class Or extends BooleanCondition {
+    private final BooleanCondition a;
+    private final BooleanCondition b;
+
+    Or(BooleanCondition a, BooleanCondition b) {
+      this.a = a;
+      this.b = b;
+    }
+
+    @Override
+    public boolean value() {
+      return a.value() || b.value();
+    }
+
+    @Override
+    public <T> Iterable<T> children(Class<T> type) {
+      return Iterables.concat(a.children(type), b.children(type));
+    }
+
+    @Override
+    public int hashCode() {
+      return a.hashCode() * 31 + b.hashCode();
+    }
+
+    @Override
+    public boolean equals(Object other) {
+      if (other instanceof Or) {
+        Or o = (Or) other;
+        return a.equals(o.a) && b.equals(o.b);
+      }
+      return false;
+    }
+
+    @Override
+    public String toString() {
+      return "(" + maybeTrim(a, getClass()) + " || " + maybeTrim(a, getClass()) + ")";
+    }
+  }
+
+  private static final class Not extends BooleanCondition {
+    private final BooleanCondition cond;
+
+    Not(BooleanCondition bc) {
+      cond = bc;
+    }
+
+    @Override
+    public boolean value() {
+      return !cond.value();
+    }
+
+    @Override
+    public <T> Iterable<T> children(Class<T> type) {
+      return cond.children(type);
+    }
+
+    @Override
+    public int hashCode() {
+      return cond.hashCode() * 31;
+    }
+
+    @Override
+    public boolean equals(Object other) {
+      return other instanceof Not ? cond.equals(((Not) other).cond) : false;
+    }
+
+    @Override
+    public String toString() {
+      return "!" + cond;
+    }
+  }
+
+  private static final class Value extends BooleanCondition {
+    private final boolean value;
+
+    Value(boolean v) {
+      value = v;
+    }
+
+    @Override
+    public boolean value() {
+      return value;
+    }
+
+    @Override
+    public <T> Iterable<T> children(Class<T> type) {
+      return Collections.emptyList();
+    }
+
+    @Override
+    public int hashCode() {
+      return value ? 1 : 0;
+    }
+
+    @Override
+    public boolean equals(Object other) {
+      return other instanceof Value ? value == ((Value) other).value : false;
+    }
+
+    @Override
+    public String toString() {
+      return Boolean.toString(value);
+    }
+  }
+
+  /** Remove leading '(' and trailing ')' if the type is the same as the parent. */
+  static String maybeTrim(BooleanCondition cond, Class<? extends BooleanCondition> type) {
+    String s = cond.toString();
+    if (cond.getClass() == type
+        && s.length() > 2
+        && s.charAt(0) == '('
+        && s.charAt(s.length() - 1) == ')') {
+      s = s.substring(1, s.length() - 1);
+    }
+    return s;
+  }
+}

gerrit-extension-api/src/main/java/com/google/gerrit/extensions/conditions/PrivateInternals_BooleanCondition.java

@@ -0,0 +1,33 @@
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.extensions.conditions;
+
+import java.util.Collections;
+
+/** <b>DO NOT USE</b> */
+public final class PrivateInternals_BooleanCondition {
+  private PrivateInternals_BooleanCondition() {}
+
+  public abstract static class SubclassOnlyInCoreServer extends BooleanCondition {
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> Iterable<T> children(Class<T> type) {
+      if (type.isAssignableFrom(getClass())) {
+        return Collections.singleton((T) this);
+      }
+      return Collections.emptyList();
+    }
+  }
+}

gerrit-extension-api/src/main/java/com/google/gerrit/extensions/webui/UiAction.java

@@ -14,6 +14,7 @@
 
 package com.google.gerrit.extensions.webui;
 
+import com.google.gerrit.extensions.conditions.BooleanCondition;
 import com.google.gerrit.extensions.restapi.RestResource;
 import com.google.gerrit.extensions.restapi.RestView;
 
@@ -35,8 +36,8 @@ public interface UiAction<R extends RestResource> extends RestView<R> {
     private String id;
     private String label;
     private String title;
-    private boolean visible = true;
-    private boolean enabled = true;
+    private BooleanCondition visible = BooleanCondition.TRUE;
+    private BooleanCondition enabled = BooleanCondition.TRUE;
 
     public String getMethod() {
       return method;
@@ -77,6 +78,10 @@ public interface UiAction<R extends RestResource> extends RestView<R> {
     }
 
     public boolean isVisible() {
+      return getVisibleCondition().value();
+    }
+
+    public BooleanCondition getVisibleCondition() {
       return visible;
     }
 
@@ -85,16 +90,33 @@ public interface UiAction<R extends RestResource> extends RestView<R> {
      * action description may not be sent to the client.
      */
     public Description setVisible(boolean visible) {
+      return setVisible(BooleanCondition.valueOf(visible));
+    }
+
+    /**
+     * Set if the action's button is visible on screen for the current client. If not visible the
+     * action description may not be sent to the client.
+     */
+    public Description setVisible(BooleanCondition visible) {
       this.visible = visible;
       return this;
     }
 
     public boolean isEnabled() {
-      return enabled && isVisible();
+      return getEnabledCondition().value();
+    }
+
+    public BooleanCondition getEnabledCondition() {
+      return BooleanCondition.and(enabled, visible);
     }
 
     /** Set if the button should be invokable (true), or greyed out (false). */
     public Description setEnabled(boolean enabled) {
+      return setEnabled(BooleanCondition.valueOf(enabled));
+    }
+
+    /** Set if the button should be invokable (true), or greyed out (false). */
+    public Description setEnabled(BooleanCondition enabled) {
       this.enabled = enabled;
       return this;
     }