properties.put("license." + i + ".name", license.getName());
            properties.put("license." + i + ".url", license.getUrl());
            properties.put("license." + i + ".comments", license.getComments());
            properties.put("license." + i + ".distribution", license.getDistribution());
        }

        result.setProperties(properties);

        setArtifactProperties(result, model);

        Map<String, String> properties = new HashMap<>();
        properties.put(ArtifactProperties.TYPE, id);
        properties.put(ArtifactProperties.LANGUAGE, language.id());
        properties.put(MavenArtifactProperties.INCLUDES_DEPENDENCIES, Boolean.toString(includesDependencies));
        properties.put(
                MavenArtifactProperties.CONSTITUTES_BUILD_PATH,

        assertNotNull(result.getProblems());
        assertEquals(0, result.getProblems().size());
    }

    @Test
    void testBuildRequestWithUserToolchains() throws Exception {
        Properties props = new Properties();
        props.put("key", "user_value");
        ToolchainModel toolchain = new ToolchainModel();
        toolchain.setType("TYPE");
        toolchain.setProvides(props);

    }

    private
    fun createProperties() = Properties().also { properties ->
        properties["runtime"] = runtime.get().joinToString(",")
        properties["projects"] = projects.get().joinToString(",")
        optionalProjects.get().takeIf { it.isNotEmpty() }?.let { optional ->
            properties["optional"] = optional.joinForProperties()
        }
    }

    private

    MavenExecutionRequest setSystemProperties(Properties systemProperties);

    /**
     * Gets the system properties to use for interpolation and profile activation. The system properties are collected
     * from the runtime environment like {@link System#getProperties()} and environment variables.
     *
     * @return The system properties, never {@code null}.
     */
    Properties getSystemProperties();

    /**

            properties.put("license." + i + ".name", license.getName());
            properties.put("license." + i + ".url", license.getUrl());
            properties.put("license." + i + ".comments", license.getComments());
            properties.put("license." + i + ".distribution", license.getDistribution());
        }

        result.setProperties(properties);

        setArtifactProperties(result, model);

        }

        return this;
    }

    @Override
    public Properties getSystemProperties() {
        if (systemProperties == null) {
            systemProperties = new Properties();
        }

        return systemProperties;
    }

    @Override
    public DefaultModelBuildingRequest setSystemProperties(Properties systemProperties) {
        if (systemProperties != null) {

import org.gradle.internal.properties.PropertyValue
import org.gradle.internal.properties.PropertyVisitor
import org.gradle.internal.properties.annotations.AbstractPropertyAnnotationHandler
import org.gradle.internal.properties.annotations.DefaultTypeMetadataStore
import org.gradle.internal.properties.annotations.MissingPropertyAnnotationHandler
import org.gradle.internal.properties.annotations.PropertyMetadata

+-----+
${maven.home}
     |
     +--- maven.properties
+-----+

* Group configuration

 As far as properties go for an entire build the maven.properties could be placed at
 the top of the group but I'm not really sure how this might work. There could probably
 also be a directory for plugins.xml and maven.properties.

* Project configuration

import java.util.NoSuchElementException;
import java.util.Set;

class PropertiesAsMap extends AbstractMap<String, String> {

    private final Map<Object, Object> properties;

    PropertiesAsMap(Map<Object, Object> properties) {
        this.properties = properties;
    }

    @Override
    public Set<Entry<String, String>> entrySet() {
        return new AbstractSet<Entry<String, String>>() {
            @Override