Merge "Reduce BooleanCondition predicate tree before evaluating permissions"

javatests/com/google/gerrit/extensions/conditions/BUILD

@@ -0,0 +1,10 @@
+load("//tools/bzl:junit.bzl", "junit_tests")
+
+junit_tests(
+    name = "conditions_tests",
+    srcs = glob(["*.java"]),
+    deps = [
+        "//java/com/google/gerrit/extensions:lib",
+        "//lib:truth",
+    ],
+)

javatests/com/google/gerrit/extensions/conditions/BooleanConditionTest.java

@@ -0,0 +1,152 @@
+// Copyright (C) 2018 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 static com.google.gerrit.extensions.conditions.BooleanCondition.and;
+import static com.google.gerrit.extensions.conditions.BooleanCondition.not;
+import static com.google.gerrit.extensions.conditions.BooleanCondition.or;
+import static com.google.gerrit.extensions.conditions.BooleanCondition.valueOf;
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+public class BooleanConditionTest {
+
+  private static final BooleanCondition NO_TRIVIAL_EVALUATION =
+      new BooleanCondition() {
+        @Override
+        public boolean value() {
+          throw new UnsupportedOperationException("value() is not supported");
+        }
+
+        @Override
+        public <T> Iterable<T> children(Class<T> type) {
+          throw new UnsupportedOperationException("children(Class<T> type) is not supported");
+        }
+
+        @Override
+        public BooleanCondition reduce() {
+          return this;
+        }
+
+        @Override
+        protected boolean evaluatesTrivially() {
+          return false;
+        }
+      };
+
+  @Test
+  public void reduceAnd_CutOffNonTrivialWhenPossible() throws Exception {
+    BooleanCondition nonReduced = and(false, NO_TRIVIAL_EVALUATION);
+    BooleanCondition reduced = valueOf(false);
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+
+  @Test
+  public void reduceAnd_CutOffNonTrivialWhenPossibleSwapped() throws Exception {
+    BooleanCondition nonReduced = and(NO_TRIVIAL_EVALUATION, valueOf(false));
+    BooleanCondition reduced = valueOf(false);
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+
+  @Test
+  public void reduceAnd_KeepNonTrivialWhenNoCutOffPossible() throws Exception {
+    BooleanCondition nonReduced = and(true, NO_TRIVIAL_EVALUATION);
+    BooleanCondition reduced = and(true, NO_TRIVIAL_EVALUATION);
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+
+  @Test
+  public void reduceAnd_KeepNonTrivialWhenNoCutOffPossibleSwapped() throws Exception {
+    BooleanCondition nonReduced = and(NO_TRIVIAL_EVALUATION, valueOf(true));
+    BooleanCondition reduced = and(NO_TRIVIAL_EVALUATION, valueOf(true));
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+
+  @Test
+  public void reduceOr_CutOffNonTrivialWhenPossible() throws Exception {
+    BooleanCondition nonReduced = or(true, NO_TRIVIAL_EVALUATION);
+    BooleanCondition reduced = valueOf(true);
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+
+  @Test
+  public void reduceOr_CutOffNonTrivialWhenPossibleSwapped() throws Exception {
+    BooleanCondition nonReduced = or(NO_TRIVIAL_EVALUATION, valueOf(true));
+    BooleanCondition reduced = valueOf(true);
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+
+  @Test
+  public void reduceOr_KeepNonTrivialWhenNoCutOffPossible() throws Exception {
+    BooleanCondition nonReduced = or(false, NO_TRIVIAL_EVALUATION);
+    BooleanCondition reduced = or(false, NO_TRIVIAL_EVALUATION);
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+
+  @Test
+  public void reduceOr_KeepNonTrivialWhenNoCutOffPossibleSwapped() throws Exception {
+    BooleanCondition nonReduced = or(NO_TRIVIAL_EVALUATION, valueOf(false));
+    BooleanCondition reduced = or(NO_TRIVIAL_EVALUATION, valueOf(false));
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+
+  @Test
+  public void reduceNot_ReduceIrrelevant() throws Exception {
+    BooleanCondition nonReduced = not(valueOf(true));
+    BooleanCondition reduced = valueOf(false);
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+
+  @Test
+  public void reduceNot_ReduceIrrelevant2() throws Exception {
+    BooleanCondition nonReduced = not(valueOf(false));
+    BooleanCondition reduced = valueOf(true);
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+
+  @Test
+  public void reduceNot_KeepNonTrivialWhenNoCutOffPossible() throws Exception {
+    BooleanCondition nonReduced = not(NO_TRIVIAL_EVALUATION);
+    BooleanCondition reduced = not(NO_TRIVIAL_EVALUATION);
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+
+  @Test
+  public void reduceComplexTreeToSingleValue() throws Exception {
+    //        AND
+    //       /   \
+    //      OR   NOT
+    //     /  \    \
+    //   NTE NTE  TRUE
+    BooleanCondition nonReduced =
+        and(or(NO_TRIVIAL_EVALUATION, NO_TRIVIAL_EVALUATION), not(valueOf(true)));
+    BooleanCondition reduced = valueOf(false);
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+
+  @Test
+  public void reduceComplexTreeToSmallerTree() throws Exception {
+    //        AND
+    //       /   \
+    //      OR    OR
+    //     /  \   / \
+    //   NTE NTE  T  F
+    BooleanCondition nonReduced =
+        and(or(NO_TRIVIAL_EVALUATION, NO_TRIVIAL_EVALUATION), or(valueOf(true), valueOf(false)));
+    BooleanCondition reduced = and(or(NO_TRIVIAL_EVALUATION, NO_TRIVIAL_EVALUATION), valueOf(true));
+    assertEquals(nonReduced.reduce(), reduced);
+  }
+}