Spiked making performance testing outside of the gradle main project.…

… It's not really possible as I need various things:

1. good way of running gradle (tooling api is almost there)
2. good way of using previous versions of gradle
So... the performance testing probably goes under the main gradle project.

performanceTest/build.gradle

@@ -7,6 +7,7 @@ idea.project.jdkName = '1.6'
 
 repositories {
     mavenCentral()
+    mavenRepo(url: 'http://repo.gradle.org/gradle/libs-releases-local')
 }
 
 configurations {
@@ -16,9 +17,15 @@ configurations {
 dependencies {
     junit 'junit:junit:4.10'
     groovy localGroovy()
+    testCompile 'junit:junit:4.10'
+
+    //spock
     testCompile 'org.spockframework:spock-core:0.5-groovy-1.8@jar',
-            'org.objenesis:objenesis:1.2', 'cglib:cglib-nodep:2.2',
-            'junit:junit:4.10'
+            'org.objenesis:objenesis:1.2', 'cglib:cglib-nodep:2.2'
+
+    //tooling api
+    testCompile 'org.gradle:gradle-tooling-api:1.0-milestone-7'
+    testRuntime 'org.slf4j:slf4j-simple:1.6.4'
 }
 
 task small(type: GeneratorTask, description: 'Generates a small project') {

performanceTest/src/test/groovy/org/gradle/peformance/PerformanceTest.groovy

@@ -1,14 +1,56 @@
 package org.gradle.peformance
 
 import spock.lang.Specification
+import org.gradle.tooling.GradleConnector
 
 /**
  * by Szczepan Faber, created at: 2/9/12
  */
 class PerformanceTest extends Specification {
 
-    def "foo"() {
-        expect:
-        1==1
+    def "small project"() {
+        given:
+        def projectDir = findProjectDir("small")
+
+        when:
+        int m6result = executionTime {
+            def connection = GradleConnector.newConnector()
+                .forProjectDirectory(projectDir)
+                .searchUpwards(false)
+                .useGradleVersion("1.0-milestone-6")
+                .connect()
+
+            connection.newBuild().forTasks('clean', 'build').run()
+        }
+
+        int m7result = executionTime {
+            def connection = GradleConnector.newConnector()
+                .forProjectDirectory(projectDir)
+                .searchUpwards(false)
+                .useGradleVersion("1.0-milestone-7")
+                .connect()
+
+            connection.newBuild().forTasks('clean', 'build').run()
+        }
+
+        then:
+        m7result <= m6result
+    }
+
+    long executionTime(Closure operation) {
+        long before = System.currentTimeMillis()
+        operation()
+        return System.currentTimeMillis() - before
+    }
+
+    File findProjectDir(String name) {
+        def projectDir = new File("build/small").absoluteFile
+        if (!projectDir.isDirectory()) {
+            def message = "Looks like the sample '$name' was not generated.\n" +
+                "I've tried to find it at: $projectDir\n" +
+                "Please run 'gradle $name' to generate the sample."
+            assert false: message
+        }
+        projectDir
     }
 }