// Copyright 2015 The Bazel Authors. All rights reserved.
//
// 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.devtools.build.lib.packages;

import static com.google.common.truth.Truth.assertThat;
import static org.junit.Assert.assertThrows;

import com.google.devtools.build.lib.vfs.PathFragment;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/**
 * Unit tests for {@link RelativePackageNameResolver}.
 */
@RunWith(JUnit4.class)
public class RelativePackageNameResolverTest {
  private RelativePackageNameResolver resolver;

  @Test
  public void testRelativePackagesBelowOneLevelWork() throws Exception {
    createResolver("foo", true);
    assertResolvesTo("bar", "foo/bar");

    createResolver("foo/bar", true);
    assertResolvesTo("pear", "foo/bar/pear");
  }

  @Test
  public void testRelativePackagesBelowTwoLevelsWork() throws Exception {
    createResolver("foo/bar", true);
    assertResolvesTo("pear", "foo/bar/pear");
  }

  @Test
  public void testRelativePackagesAboveOneLevelWork() throws Exception {
    createResolver("foo", true);
    assertResolvesTo("../bar", "bar");
  }

  @Test
  public void testRelativePackagesAboveTwoLevelsWork() throws Exception {
    createResolver("foo/bar", true);
    assertResolvesTo("../../apple", "apple");
  }

  @Test
  public void testSimpleAbsolutePackagesWork() throws Exception {
    createResolver("foo", true);

    assertResolvesTo("//foo", "foo");
    assertResolvesTo("//foo/bar", "foo/bar");
  }

  @Test
  public void testBuildNotRemoved() throws Exception {
    createResolver("foo", false);

    assertResolvesTo("bar/BUILD", "foo/bar/BUILD");
  }

  @Test
  public void testBuildRemoved() throws Exception {
    createResolver("foo", true);

    assertResolvesTo("bar/BUILD", "foo/bar");
  }

  @Test
  public void testEmptyOffset() throws Exception {
    createResolver("", true);

    assertResolvesTo("bar", "bar");
    assertResolvesTo("bar/qux", "bar/qux");
  }

  @Test
  public void testTooFarUpwardsOneLevelThrows() throws Exception {
    createResolver("foo", true);

    assertThrows(InvalidPackageNameException.class, () -> resolver.resolve("../../bar"));
  }

  @Test
  public void testTooFarUpwardsTwoLevelsThrows() throws Exception {
    createResolver("foo/bar", true);
    assertResolvesTo("../../orange", "orange");

    assertThrows(InvalidPackageNameException.class, () -> resolver.resolve("../../../orange"));
  }

  private void createResolver(String offset, boolean discardBuild) {
    resolver = new RelativePackageNameResolver(PathFragment.create(offset), discardBuild);
  }

  private void assertResolvesTo(String relative, String expectedAbsolute) throws Exception {
    String result = resolver.resolve(relative);
    assertThat(result).isEqualTo(expectedAbsolute);
  }
}