assertViolations(result, 0, 0, 2);

        assertEquals(
                "'profiles.profile[exists-project-version].activation.file.exists' "
                        + "Failed to interpolate profile activation property ${project.version}/test.txt: "
                        + "${project.version} expressions are not supported during profile activation.",
                result.getWarnings().get(0));

            return false;
        }

        try {
            path = profileActivationFilePathInterpolator.interpolate(path, context);
        } catch (InterpolationException e) {
            problems.add(new ModelProblemCollectorRequest(Severity.ERROR, Version.BASE)
                    .setMessage("Failed to interpolate file location " + path + " for profile " + profile.getId() + ": "
                            + e.getMessage())

    }

    @Override
    public MavenOptions interpolate(Collection<Map<String, String>> properties) {
        ArrayList<MavenOptions> interpolatedOptions = new ArrayList<>(options.size());
        for (MavenOptions o : options) {
            interpolatedOptions.add(o.interpolate(properties));
        }
        return layerMavenOptions(interpolatedOptions);
    }

    /**
     * Returns a new instance of EncryptOptions with values interpolated using the given properties.
     *
     * @param properties a collection of property maps to use for interpolation
     * @return a new EncryptOptions instance with interpolated values
     */
    @Nonnull
    EncryptOptions interpolate(Collection<Map<String, String>> properties);

    }

    public interface ContentTransformer {
        /**
         * Interpolate the value read from the xpp3 document
         *
         * @param source    the source value
         * @param fieldName a description of the field being interpolated. The implementation may use this to
         *                  log stuff
         * @return the interpolated value
         */
        String transform(String source, String fieldName);
    }

            if (configuration == null) {
                configuration = new XmlNodeImpl("configuration");
            }
            Function<String, String> cb = Interpolator.memoize(callback);
            Function<String, String> it = s -> interpolator.interpolate(s, cb);
            configuration = new ExtensionInterpolator(it).transform(configuration);

            binder.bind(XmlNode.class)

    public interface ContentTransformer {
        /**
         * Interpolate the value read from the xpp3 document
         * @param source The source value
         * @param fieldName A description of the field being interpolated. The implementation may use this to
         *                           log stuff.
         * @return The interpolated value.
         */
        String transform(String source, String fieldName);

    interface Transformer {
        /**
         * Interpolate the value read from the xml document
         *
         * @param source    The source value
         * @param fieldName A description of the field being interpolated. The implementation may use this to
         *                  log stuff.
         * @return the interpolated value
         */
        String transform(String source, String fieldName);
    }

        // system and user properties
        context.systemProperties = populateSystemProperties(context);
        context.userProperties = populateUserProperties(context);

        // options: interpolate
        context.options = context.options.interpolate(
                Arrays.asList(context.extraInterpolationSource(), context.userProperties, context.systemProperties));

        // core extensions

     */
    public interface ContentTransformer {
        /**
         * Interpolate the value read from the xpp3 document
         *
         * @param source    The source value
         * @param fieldName A description of the field being interpolated. The implementation may use this to
         *                  log stuff.
         * @return The interpolated value.
         */
        String transform(String source, String fieldName);