/**
 * A helper class to handle incremental compilation after a failure: it makes moving files around easier and reverting state easier.
 */
public class CompileTransaction {

    private static final Logger LOG = LoggerFactory.getLogger(CompileTransaction.class);

    private final Deleter deleter;
    private final FileOperations fileOperations;
    private final PatternSet classesToDelete;

    }

    CompileTransaction newCompileTransaction() {
        return new CompileTransaction(spec, new PatternSet(), Collections.emptyMap(), TestFiles.fileOperations(temporaryFolder), TestFiles.deleter())
    }

    CompileTransaction newCompileTransaction(PatternSet classesToDelete) {

        }
    }

    @Override
    public CompileTransaction initCompilationSpecAndTransaction(JavaCompileSpec spec, RecompilationSpec recompilationSpec) {
        if (!recompilationSpec.isBuildNeeded()) {
            spec.setSourceFiles(ImmutableSet.of());
            spec.setClassesToProcess(Collections.emptySet());
            return new CompileTransaction(spec, fileOperations.patternSet(), ImmutableMap.of(), fileOperations, deleter);

        given:
        source("class A {}", "class B {}")
        def compileTransactionDir = file("build/tmp/${language.compileTaskName}/compileTransaction")

        when: "First compilation is always full compilation"
        run language.compileTaskName

        then:
        outputs.recompiledClasses("A", "B")
        !compileTransactionDir.exists()