properties.setProperty("remainingProjects", ":module-a");

        repository.applyResumptionProperties(request, properties);

        assertEquals(singleton(":module-a"), request.getProjectActivation().getOptionalActiveProjectSelectors());
    }

    @Test
    void resumeFromPropertyDoesNotOverrideExistingRequestParameters() {
        MavenExecutionRequest request = new DefaultMavenExecutionRequest();

        return getProjectSelectors(pa -> !pa.optional() && pa.active());
    }

    /**
     * @return Optional active project selectors, never {@code null}.
     */
    public Set<String> getOptionalActiveProjectSelectors() {
        return getProjectSelectors(pa -> pa.optional() && pa.active());
    }

    /**
     * @return Required inactive project selectors, never {@code null}.
     */