}
            }
        """
        def manifestFile = file("build/tmp/jar/MANIFEST.MF")
        def assertCreatedBy = { creator ->
            manifestFile.assertContents(
                containsString("Created-By: $creator")
            )
        }

        when:
        configurationCacheRun ":jar", "-Dcreator=creator1"

        then:

                throw new AssertionError(String.format("%s should not exist:\n%s", this, String.join("\n", descendants)));
            }
        }
        return this;
    }

    public TestFile assertContents(Matcher<String> matcher) {
        assertThat(getText(), matcher);
        return this;
    }

    public TestFile assertIsCopyOf(TestFile other) {
        assertIsFile();
        other.assertIsFile();