ToolchainsBuildingResult result = toolchainBuilder.build(request);
        assertNotNull(result.getEffectiveToolchains());
        assertNotNull(result.getProblems());
        assertEquals(0, result.getProblems().size());
    }

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

/**
 * Signals one or more errors during settings building. The settings builder tries to collect as many problems as
 * possible before eventually failing to provide callers with rich error information. Use {@link #getProblems()} to
 * query the details of the failure.
 *
 * @deprecated since 4.0.0, use {@link org.apache.maven.api.services.SettingsBuilder} instead
 */
@Deprecated(since = "4.0.0")

        assertNotNull(actual);

        boolean hasLocation = actual.getProblems().stream()
                .anyMatch(p -> p.getLineNumber() == lineNumber && p.getColumnNumber() == columnNumber);

        if (!hasLocation) {
            String actualLocations = actual.getProblems().stream()
                    .map(p -> formatLocation(p.getColumnNumber(), p.getLineNumber()))

    public static <T> Result<T> error(Result<?> result) {
        return error(result.getProblems());
    }

    public static <T> Result<T> error(Result<?>... results) {
        final List<ModelProblem> problemsList = new ArrayList<>();

        for (Result<?> result1 : results) {
            for (ModelProblem modelProblem : result1.getProblems()) {
                problemsList.add(modelProblem);
            }
        }

     *
     * @return The problems that caused this exception, never {@code null}.
     */
    public List<ModelProblem> getProblems() {
        if (result == null) {
            return Collections.emptyList();
        }
        return Collections.unmodifiableList(result.getProblems());
    }

    private static String toMessage(ModelBuildingResult result) {

        ProblemCollector collector2 = ProblemCollectorFactory.newInstance(Collections.singletonList(problem));

        assertNotSame(collector1, collector2);
        assertEquals(0, collector1.getProblems().size());
        assertEquals(1, collector2.getProblems().size());
    }

    @Test
    void testAddProblem() {
        ProblemCollector collector = ProblemCollectorFactory.newInstance(null);
        collector.setSource("pom.xml");

        problemCollector.add(Problem.Severity.ERROR, "MESSAGE", 3, 5, new Exception());
        ToolchainsBuildingException e = new ToolchainsBuildingException(problemCollector.getProblems());
        assertEquals(
                "1 problem was encountered while building the effective toolchains" + LS
                        + "[ERROR] MESSAGE @ line 3, column 5" + LS,
                e.getMessage());
    }

        }

        long totalProblems = 0;
        long errorProblems = 0;

        for (ProjectBuildingResult result : results) {
            List<ModelProblem> problems = result.getProblems();
            totalProblems += problems.size();

            for (ModelProblem problem : problems) {
                if (problem.getSeverity() != ModelProblem.Severity.WARNING) {
                    errorProblems++;

                }

                @Nonnull
                @Override
                public Collection<BuilderProblem> getProblems() {
                    return new MappedCollection<>(res.getProblems(), this::toProblem);
                }

                private BuilderProblem toProblem(ModelProblem problem) {
                    return new BuilderProblem() {

        assertNotNull(actual);

        boolean hasMessage =
                actual.getProblems().stream().anyMatch(p -> p.getMessage().contains(problemMessage));

        if (!hasMessage) {
            String actualMessages = actual.getProblems().stream()
                    .map(ModelProblem::getMessage)
                    .map(m -> "\"" + m + "\"")