}

    public void test_expandPath() {
        // Test expandPath method
        generator = new TestThumbnailGenerator();

        // Test without mappings
        assertEquals("path/to/file", generator.expandPath("path/to/file"));
        assertNull(generator.expandPath(null));

        // Test with exact match mappings (expandPath only replaces exact matches)

        assertEquals("test/path", emptyGenerator.expandPath("test/path"));
        assertNull(emptyGenerator.expandPath(null));

        // Test with file path mappings
        emptyGenerator.filePathMap.put("${path}/test", "/usr/bin/test");
        assertEquals("/usr/bin/test", emptyGenerator.expandPath("${path}/test"));
        assertEquals("other/path", emptyGenerator.expandPath("other/path"));
    }