}
            }
            tasks.register("mytask", MyTask) {
                def layout = project.layout
                conventionMapping.map("foo") { $directoryExpression }
                conventionMapping.map("bar") { $fileExpression }
            }
        """

        expect:
        succeeds 'mytask'

        where:

import javax.annotation.Nullable;
import java.util.concurrent.Callable;

/**
 * <p>A {@code ConventionMapping} maintains the convention mappings for the properties of a particular object.</p>
 *
 * <p>Implementations should also allow mappings to be set using dynamic properties.</p>
 */
public interface ConventionMapping {

    MappedProperty map(String propertyName, Closure<?> value);

public abstract class ConventionTask extends DefaultTask implements IConventionAware {
    private ConventionMapping conventionMapping;

    public Task conventionMapping(String property, Callable<?> mapping) {
        getConventionMapping().map(property, mapping);
        return this;
    }

    public Task conventionMapping(String property, Closure mapping) {
        getConventionMapping().map(property, mapping);
        return this;

            taskReportTask.setDescription("Generates a report about your tasks.");
            taskReportTask.conventionMapping("outputFile", () -> taskReportTask.getProjectReportDirectory().file("tasks.txt").get().getAsFile());
            taskReportTask.conventionMapping("projects", () -> WrapUtil.toSet(project));
        });

        return extensionContainer;
    }

    @Override
    public ConventionMapping getConventionMapping() {
        if (conventionMapping == null) {
            this.conventionMapping = DeprecationLogger.whileDisabled(() ->
                toType(object, IConventionAware.class).getConventionMapping()
            );
        }
        return conventionMapping;
    }

    public Class<?> getDeclaredType() {

                    assert foo.files == layout.files("file1", "file2").files
                    assert foo.files.size() == 2
                }
            }
            tasks.register("mytask", MyTask) {
                conventionMapping.map("foo") { bar }
                bar.setFrom("file1", "file2")
            }
        """

        expect:
        succeeds 'mytask'
    }

import org.gradle.api.Action;
import org.gradle.api.Plugin;
import org.gradle.api.Task;
import org.gradle.api.artifacts.Configuration;
import org.gradle.api.file.Directory;
import org.gradle.api.internal.ConventionMapping;
import org.gradle.api.internal.IConventionAware;
import org.gradle.api.internal.project.ProjectInternal;
import org.gradle.api.plugins.JavaBasePlugin;
import org.gradle.api.plugins.JavaPluginExtension;

     * manage the mapping for individual properties.
     *
     * @return The mapping. Never returns null.
     */
    ConventionMapping getConventionMapping();

import org.gradle.api.artifacts.Configuration;
import org.gradle.api.file.Directory;
import org.gradle.api.file.ProjectLayout;
import org.gradle.api.file.RegularFile;
import org.gradle.api.internal.ConventionMapping;
import org.gradle.api.plugins.quality.internal.AbstractCodeQualityPlugin;
import org.gradle.api.provider.Provider;
import org.gradle.api.provider.ProviderFactory;
import org.gradle.api.resources.TextResource;

import org.gradle.api.artifacts.Configuration;
import org.gradle.api.file.ProjectLayout;
import org.gradle.api.file.RegularFile;
import org.gradle.api.file.SourceDirectorySet;
import org.gradle.api.internal.ConventionMapping;
import org.gradle.api.plugins.GroovyBasePlugin;
import org.gradle.api.plugins.JvmEcosystemPlugin;
import org.gradle.api.plugins.quality.internal.AbstractCodeQualityPlugin;
import org.gradle.api.provider.Provider;