| /* |
| * Copyright (C) 2014 The Guava Authors |
| * |
| * 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.common.graph; |
| |
| import static com.google.common.graph.GraphConstants.ENDPOINTS_MISMATCH; |
| import static com.google.common.truth.Truth.assertThat; |
| import static org.junit.Assert.fail; |
| |
| import org.junit.Test; |
| |
| /** |
| * Abstract base class for testing implementations of {@link Graph} interface. |
| * |
| * <p>This class is responsible for testing that a directed implementation of {@link Graph} is |
| * correctly handling directed edges. Implementation-dependent test cases are left to subclasses. |
| * Test cases that do not require the graph to be directed are found in superclasses. |
| */ |
| public abstract class AbstractDirectedGraphTest extends AbstractGraphTest { |
| @Test |
| public void predecessors_oneEdge() { |
| putEdge(N1, N2); |
| assertThat(graph.predecessors(N2)).containsExactly(N1); |
| // Edge direction handled correctly |
| assertThat(graph.predecessors(N1)).isEmpty(); |
| } |
| |
| @Test |
| public void successors_oneEdge() { |
| putEdge(N1, N2); |
| assertThat(graph.successors(N1)).containsExactly(N2); |
| // Edge direction handled correctly |
| assertThat(graph.successors(N2)).isEmpty(); |
| } |
| |
| @Test |
| public void incidentEdges_oneEdge() { |
| putEdge(N1, N2); |
| EndpointPair<Integer> expectedEndpoints = EndpointPair.ordered(N1, N2); |
| assertThat(graph.incidentEdges(N1)).containsExactly(expectedEndpoints); |
| assertThat(graph.incidentEdges(N2)).containsExactly(expectedEndpoints); |
| } |
| |
| @Test |
| public void inDegree_oneEdge() { |
| putEdge(N1, N2); |
| assertThat(graph.inDegree(N2)).isEqualTo(1); |
| // Edge direction handled correctly |
| assertThat(graph.inDegree(N1)).isEqualTo(0); |
| } |
| |
| @Test |
| public void outDegree_oneEdge() { |
| putEdge(N1, N2); |
| assertThat(graph.outDegree(N1)).isEqualTo(1); |
| // Edge direction handled correctly |
| assertThat(graph.outDegree(N2)).isEqualTo(0); |
| } |
| |
| @Test |
| public void hasEdgeConnecting_correct() { |
| putEdge(N1, N2); |
| assertThat(graph.hasEdgeConnecting(EndpointPair.ordered(N1, N2))).isTrue(); |
| } |
| |
| @Test |
| public void hasEdgeConnecting_backwards() { |
| putEdge(N1, N2); |
| assertThat(graph.hasEdgeConnecting(EndpointPair.ordered(N2, N1))).isFalse(); |
| } |
| |
| @Test |
| public void hasEdgeConnecting_mismatch() { |
| putEdge(N1, N2); |
| assertThat(graph.hasEdgeConnecting(EndpointPair.unordered(N1, N2))).isFalse(); |
| assertThat(graph.hasEdgeConnecting(EndpointPair.unordered(N2, N1))).isFalse(); |
| } |
| |
| // Element Mutation |
| |
| @Test |
| public void putEdge_existingNodes() { |
| // Adding nodes initially for safety (insulating from possible future |
| // modifications to proxy methods) |
| addNode(N1); |
| addNode(N2); |
| assertThat(putEdge(N1, N2)).isTrue(); |
| } |
| |
| @Test |
| public void putEdge_existingEdgeBetweenSameNodes() { |
| assertThat(putEdge(N1, N2)).isTrue(); |
| assertThat(putEdge(N1, N2)).isFalse(); |
| } |
| |
| @Test |
| public void putEdge_orderMismatch() { |
| EndpointPair<Integer> endpoints = EndpointPair.unordered(N1, N2); |
| try { |
| putEdge(endpoints); |
| fail("Expected IllegalArgumentException: " + ENDPOINTS_MISMATCH); |
| } catch (IllegalArgumentException e) { |
| assertThat(e).hasMessageThat().contains(ENDPOINTS_MISMATCH); |
| } |
| } |
| |
| public void removeEdge_antiparallelEdges() { |
| putEdge(N1, N2); |
| putEdge(N2, N1); |
| |
| assertThat(graph.removeEdge(N1, N2)).isTrue(); |
| assertThat(graph.successors(N1)).isEmpty(); |
| assertThat(graph.predecessors(N1)).containsExactly(N2); |
| assertThat(graph.edges()).hasSize(1); |
| |
| assertThat(graph.removeEdge(N2, N1)).isTrue(); |
| assertThat(graph.successors(N1)).isEmpty(); |
| assertThat(graph.predecessors(N1)).isEmpty(); |
| assertThat(graph.edges()).isEmpty(); |
| } |
| |
| @Test |
| public void removeEdge_orderMismatch() { |
| putEdge(N1, N2); |
| EndpointPair<Integer> endpoints = EndpointPair.unordered(N1, N2); |
| try { |
| graph.removeEdge(endpoints); |
| fail("Expected IllegalArgumentException: " + ENDPOINTS_MISMATCH); |
| } catch (IllegalArgumentException e) { |
| assertThat(e).hasMessageThat().contains(ENDPOINTS_MISMATCH); |
| } |
| } |
| } |