sourceFile("org/gradle/test/BuildClass.java").text = buildClassSource
            buildJar(reproducibleJar)
        }
        artifactBuilder().tap {
            preserveTimestamps(true)
            sourceFile("org/gradle/test/BuildClass.java").text = buildClassSource
            buildJar(currentTimestampJar)
        }

        Closure<String> subprojectSource = {File jarPath -> """

        builder.sourceFile("org/gradle/test/DepClass.java").writelns(
                "package org.gradle.test;",
                "public class DepClass { }"
        );
        builder.buildJar(testFile("repo/test-1.3.jar"));

        testFile("buildSrc/build.gradle").writelns(
                "repositories { flatDir { dirs '../repo' } }",
                "dependencies { implementation name: 'test', version: '1.3' }");

        this.inPlaceBuilder = new InPlaceClasspathBuilder();
    }

    @Override
    public void jar(File jarFile, Action action) {
        try {
            buildJar(jarFile, action);
        } catch (Exception e) {
            throw new GradleException(String.format("Failed to create Jar file %s.", jarFile), e);
        }
    }

    @Override

        } catch (java.net.URISyntaxException e) {
            throw new RuntimeException(e);
        }
    }
}
"""
        builder.buildJar(implJar)

        def cl1 = new URLClassLoader([implJar.toURI().toURL()] as URL[], getClass().classLoader)
        def action1 = cl1.loadClass("ActionImpl").getConstructor().newInstance()

        when:

    }
}
'''
        builder.resourceFile('META-INF/gradle-plugins/custom.properties') << '''
implementation-class=CustomPlugin
'''
        builder.buildJar(file('external.jar'))

        and:
        file('build.gradle') << '''
buildscript {
    dependencies {
        classpath files('external.jar')
    }
}
apply plugin: 'custom'
assert 'value' == prop

    TestFile sourceFile(String path);

    TestFile resourceFile(String path);

    void manifestAttributes(Map<String, String> attributes);

    void preserveTimestamps(boolean preserveTimestamps);

    void buildJar(File jarFile);

    @Override
    public void jar(File jarFile, Action action) {
        try {
            buildJar(jarFile, action);
        } catch (Exception e) {
            throw new GradleException(String.format("Failed to create Jar file %s.", jarFile), e);
        }
    }

    private static void buildJar(File jarFile, Action action) throws IOException {
        Files.createDirectories(jarFile.getParentFile().toPath());

                    return null;
                }
            }
        """
        def jar = temporaryFolder.file("work folder", "action-impl.jar")
        builder.buildJar(jar)

        when:
        def classloader = new URLClassLoader([jar.toURL()] as URL[], getClass().classLoader)
        def action = classloader.loadClass("ActionImpl").getConstructor().newInstance()

        javaPlugin(builder.sourceFile("SneakyPlugin.java"), read)
        builder.resourceFile("META-INF/gradle-plugins/sneaky.properties") << """
implementation-class: SneakyPlugin
        """
        builder.buildJar(jar)
        buildFile << """
            plugins { id("sneaky") }
        """
    }

    static class TestKitBackedGradleExecuter extends AbstractGradleExecuter {
        List<File> pluginClasspath = []

            throw new IllegalArgumentException("Cannot set up timestamps on Gradle before 3.4");
        }
        shouldPreserveTimestamps = preserveTimestamps;
    }

    @Override
    public void buildJar(File jarFile) {
        String conf = isGradleExecuterVersionLessThan("3.4") ? "compile" : "implementation";
        String destinationDir = isGradleExecuterVersionLessThan("5.1") ? "destinationDir" : "destinationDirectory";