then:
        def e = thrown ModelPath.InvalidPathException
        e.cause instanceof ModelPath.InvalidNameException

        when:
        ModelPath.validatePath("foo.bar")

        then:
        noExceptionThrown()

        when:
        ModelPath.validatePath(".foo.bar")

        then:
        e = thrown ModelPath.InvalidPathException
        e.message =~ "start with"

        when:

        }
    }

    public static void validatePath(String path) throws InvalidPathException {
        if (path.isEmpty()) {
            throw new InvalidPathException("Cannot use an empty string as a model path.", null);
        }

        if (path.startsWith(SEPARATOR)) {
            throw new InvalidPathException(String.format("Model path '%s' cannot start with name separator '%s'.", path, SEPARATOR), null);
        }

                error(argExpression, INVALID_ARGUMENT_LIST);
                return;
            }

            try {
                ModelPath.validatePath(modelPath);
            } catch (ModelPath.InvalidPathException e) {
                // TODO find a better way to present this information in the error message
                // Attempt to mimic Gradle nested exception output

Class <org.gradle.model.internal.core.ModelPath$InvalidNameException> is not annotated (directly or via its package) with @org.gradle.api.NonNullApi in (ModelPath.java:0)
Class <org.gradle.model.internal.core.ModelPath$InvalidPathException> is not annotated (directly or via its package) with @org.gradle.api.NonNullApi in (ModelPath.java:0)