Rerun test/stub generation when 'clean' was called; fixes gh-1514

spring-cloud-contract-tools/spring-cloud-contract-maven-plugin/src/main/java/org/springframework/cloud/contract/maven/verifier/ChangeDetector.java

@@ -31,7 +31,9 @@ final class ChangeDetector {
 
 	static boolean inputFilesChangeDetected(File contractsDirectory, MojoExecution mojoExecution, MavenSession session)
 			throws MojoExecutionException {
-
+		if (session.getGoals().contains("clean")) {
+			return true;
+		}
 		IncrementalBuildHelper incrementalBuildHelper = new IncrementalBuildHelper(mojoExecution, session);
 
 		DirectoryScanner scanner = incrementalBuildHelper.getDirectoryScanner();

spring-cloud-contract-tools/spring-cloud-contract-maven-plugin/src/test/java/org/springframework/cloud/contract/maven/verifier/ChangeDetectorTests.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2013-2020 the original author or 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
+ *
+ *      https://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 org.springframework.cloud.contract.maven.verifier;
+
+import java.io.File;
+import java.util.Arrays;
+
+import org.apache.maven.execution.MavenSession;
+import org.apache.maven.plugin.MojoExecutionException;
+import org.junit.jupiter.api.Test;
+import org.mockito.BDDMockito;
+
+import static org.assertj.core.api.BDDAssertions.then;
+import static org.mockito.BDDMockito.given;
+
+class ChangeDetectorTests {
+
+	@Test
+	void should_mark_that_input_files_have_changed_when_goal_clean_was_called() throws MojoExecutionException {
+		MavenSession session = BDDMockito.mock(MavenSession.class);
+		given(session.getGoals()).willReturn(Arrays.asList("clean", "install"));
+
+		then(ChangeDetector.inputFilesChangeDetected(new File("."), null, session)).isTrue();
+	}
+}