[Bug]: CtCase<?>::getIncludesDefault only works with multiple case expressions

[ravatex]

Describe the bug

This may be intented as the javadoc specifies: Returns whether this case includes a trailing default.
But I interpreted it as even if there is only a default statement that should still return true.

Here is a corresponding test case that passes (taken from test/pattern/SwitchPatternTest.java)

	@Test
	void testCaseNullDefault() {
		// contract: "case null, default" is represented by a null literal and the includesDefault property set to true
		CtSwitch<?> sw = createFromSwitchStatement("case null, default", false);
		CtCase<?> ctCase = sw.getCases().get(0);
		List<? extends CtExpression<?>> caseExpressions = ctCase.getCaseExpressions();
		assertThat(caseExpressions).hasSize(1);
		assertThat(ctCase.getIncludesDefault()).isTrue();
		assertThat(ctCase.toString()).contains("case null, default ->");
	}

Source code you are trying to analyze/transform

Source code for your Spoon processing

@Test
    void failingTestCase() {
        CtSwitch<?> sw = createFromSwitchStatement("case default", false);

        CtCase<?> ctCase = sw.getCases().get(0);
        assertTrue(ctCase.getIncludesDefault());

    }

    private static CtSwitch<?> createFromSwitchStatement(String cases, boolean def) {
        return createModelFromString(
                """
                    class Foo {
                        void foo(Object arg) {
                            switch (arg) {
                                %s -> {}
                                %s
                            }
                    }
                    """.formatted(cases, def ? "default -> {}" : ""))
                .getElements(new TypeFilter<>(CtSwitch.class)).iterator().next();
    }
    private static CtModel createModelFromString(String code) {
        Launcher launcher = new Launcher();
        launcher.getEnvironment().setComplianceLevel(22);
        launcher.addInputResource(new VirtualFile(code));
        return launcher.buildModel();
    }

Actual output

false instead of true

Expected output

true

Spoon Version

11.3.1-beta-7

JVM Version

Java 21

What operating system are you using?

Linux x86-64