Switch to plugins{} apply syntax

Now that Spring Cloud Contract is generating a plugin marker, it's much
easier to functionally test using Gradle TestKit by utilizing the
withPluginClasspath() and the 'java-gradle-plugin' Gradle plugin. Since
Gradle recommends new users, as well as new plugin authors, to use the
plugin markers and plugins{} syntax we should also follow that same
path. Especially given that there has been feature parity with the
buildscirpt{} block some releases ago.

spring-cloud-contract-tools/spring-cloud-contract-gradle-plugin/src/test/groovy/org/springframework/cloud/contract/verifier/plugin/ContractVerifierIntegrationSpec.groovy

@@ -51,21 +51,6 @@ abstract class ContractVerifierIntegrationSpec extends Specification {
 
 	protected void setupForProject(String projectRoot) {
 		copyResourcesToRoot(projectRoot)
-		Properties pluginClasspathProperties = new Properties()
-		pluginClasspathProperties.load(this.class.getResourceAsStream("/plugin-under-test-metadata.properties"))
-		List<String> classpath = pluginClasspathProperties.getProperty("implementation-classpath").split(";").collect { it.replaceAll("\\\\", "/") }
-
-		initFile.write """
-			allprojects {
-				buildscript {
-					dependencies {
-						classpath(files(\"${classpath.join("\",\"")}\"))
-					}
-				}
-			}
-		"""
-		// Extending buildscript is required when 'apply' is used.
-		// 'GradleRunner#withPluginClasspath' can be used when plugin is added using 'plugins { id...'
 	}
 
 	protected void switchToJunitTestFramework() {
@@ -105,13 +90,10 @@ abstract class ContractVerifierIntegrationSpec extends Specification {
 	}
 
 	protected BuildResult run(String... tasks) {
-		List<String> arguments = new ArrayList<>()
-		arguments.addAll(tasks)
-		arguments.add("-I" + getInitFile().absolutePath)
-
 		return GradleRunner.create()
 						   .withProjectDir(testProjectDir)
-						   .withArguments(arguments)
+						   .withArguments(tasks)
+						   .withPluginClasspath()
 //						   .withDebug(true)
 						   .forwardOutput()
 						   .build()
@@ -151,10 +133,6 @@ abstract class ContractVerifierIntegrationSpec extends Specification {
 		return new File(testProjectDir, 'build.gradle')
 	}
 
-	protected File getInitFile() {
-		return new File(testProjectDir, 'init.gradle')
-	}
-
 	protected boolean jarContainsContractVerifierContracts(String path) {
 		assert fileExists(path)
 		File rootFile = file(path)

spring-cloud-contract-tools/spring-cloud-contract-gradle-plugin/src/test/resources/functionalTest/scenarioProject/build.gradle

@@ -14,18 +14,9 @@
  * limitations under the License.
  */
 
-
-buildscript {
-	repositories {
-		mavenCentral()
-		mavenLocal()
-		maven { url "https://repo.spring.io/snapshot" }
-		maven { url "https://repo.spring.io/milestone" }
-		maven { url "https://repo.spring.io/release" }
-	}
-	dependencies {
-		classpath("org.springframework.boot:spring-boot-gradle-plugin:${bootVersion}")
-	}
+plugins {
+	id("org.springframework.boot") apply false
+	id("org.springframework.cloud.contract") apply false
 }
 
 ext {
@@ -69,7 +60,7 @@ subprojects {
 configure([project(':fraudDetectionService'), project(':loanApplicationService')]) {
 	apply plugin: 'org.springframework.boot'
 	apply plugin: 'io.spring.dependency-management'
-	apply plugin: 'spring-cloud-contract'
+	apply plugin: 'org.springframework.cloud.contract'
 
 	// tag::jar_setup[]
 	ext {

spring-cloud-contract-tools/spring-cloud-contract-gradle-plugin/src/test/resources/functionalTest/scenarioProject/settings.gradle

@@ -14,6 +14,24 @@
  * limitations under the License.
  */
 
+pluginManagement {
+    repositories {
+        mavenCentral()
+        mavenLocal()
+        maven { url "https://repo.spring.io/snapshot" }
+        maven { url "https://repo.spring.io/milestone" }
+        maven { url "https://repo.spring.io/release" }
+    }
+    resolutionStrategy {
+        eachPlugin {
+            if (requested.id.id == "org.springframework.boot") {
+                useModule("org.springframework.boot:spring-boot-gradle-plugin:${bootVersion}")
+            } else if (requested.id.id == "org.springframework.cloud.contract") {
+                useModule("org.springframework.cloud:spring-cloud-contract-gradle-plugin:${verifierVersion}")
+            }
+        }
+    }
+}
 
 include ':fraudDetectionService'
 include ':loanApplicationService'

spring-cloud-contract-tools/spring-cloud-contract-gradle-plugin/src/test/resources/functionalTest/scenarioProjectKotlin/build.gradle.kts

@@ -14,21 +14,6 @@
  * limitations under the License.
  */
 
-buildscript {
-	val bootVersion: String by extra
-
-	repositories {
-		mavenCentral()
-		mavenLocal()
-		maven(url = "https://repo.spring.io/snapshot")
-		maven(url = "https://repo.spring.io/milestone")
-		maven(url = "https://repo.spring.io/release")
-	}
-	dependencies {
-		classpath("org.springframework.boot:spring-boot-gradle-plugin:$bootVersion")
-	}
-}
-
 import org.springframework.cloud.contract.stubrunner.spring.StubRunnerProperties
 import org.springframework.cloud.contract.verifier.config.TestFramework
 import org.springframework.cloud.contract.verifier.config.TestMode
@@ -36,7 +21,8 @@ import org.springframework.cloud.contract.verifier.plugin.ContractVerifierExtens
 
 plugins {
 	groovy
-//	id("org.springframework.cloud.contract")
+	id("org.springframework.boot") apply false
+	id("org.springframework.cloud.contract") apply false
 }
 
 val restAssuredVersion by extra("3.0.7")
@@ -78,7 +64,7 @@ subprojects {
 configure(listOf(project(":fraudDetectionService"), project(":loanApplicationService"))) {
 	apply(plugin = "org.springframework.boot")
 	apply(plugin = "io.spring.dependency-management")
-	apply(plugin = "spring-cloud-contract")
+	apply(plugin = "org.springframework.cloud.contract")
 	apply(plugin = "maven-publish")
 
 	configure<ContractVerifierExtension> {

spring-cloud-contract-tools/spring-cloud-contract-gradle-plugin/src/test/resources/functionalTest/scenarioProjectKotlin/settings.gradle.kts

@@ -14,6 +14,26 @@
  * limitations under the License.
  */
 
+pluginManagement {
+    repositories {
+        mavenCentral()
+        mavenLocal()
+        maven(url = "https://repo.spring.io/snapshot")
+        maven(url = "https://repo.spring.io/milestone")
+        maven(url = "https://repo.spring.io/release")
+    }
+    resolutionStrategy {
+        eachPlugin {
+            if (requested.id.id == "org.springframework.boot") {
+                val bootVersion: String by extra
+                useModule("org.springframework.boot:spring-boot-gradle-plugin:$bootVersion")
+            } else if (requested.id.id == "org.springframework.cloud.contract") {
+                val verifierVersion: String by extra
+                useModule("org.springframework.cloud:spring-cloud-contract-gradle-plugin:$verifierVersion")
+            }
+        }
+    }
+}
 
 include(":fraudDetectionService")
 include(":loanApplicationService")