for (char c : validChars.toCharArray()) {
            assertTrue("Character '" + c + "' should be a valid URL character", CharUtil.isUrlChar(c));
        }
    }

    public void test_isUrlChar_boundaryChars() {
        // Test boundary characters for ranges
        assertTrue(CharUtil.isUrlChar('a')); // first lowercase

        /**
         * Compiles a robots.txt path pattern into a regular expression pattern.
         * According to RFC 9309:
         * - '*' matches any sequence of characters (including the empty sequence)
         * - '$' matches the end of the URL path
         * - All other characters are matched literally
         *
         * @param pattern the robots.txt path pattern
         * @return the compiled Pattern object
         */

        // Test all special characters
        String input = "Test & < > \"quote\" 'apos'";
        String expected = "Test &amp; &lt; &gt; &quot;quote&quot; &apos;apos&apos;";
        assertEquals(expected, XmlUtil.escapeXml(input));
    }

    public void test_escapeXml_noSpecialChars() {
        // Test string without special characters
        String input = "Simple text without special characters";

            assertTrue("Error message should contain 'text content'", message.contains("text content"));
        }
    }

    /**
     * Test extraction with special characters and control characters.
     */
    public void test_getText_withSpecialCharacters_handlesCorrectly() {
        final String specialContent = "Tab\there\nNewline\rCarriage return\0Null byte";

{* ../../docs_src/query_params_str_validations/tutorial004_an_py310.py hl[11] *}

This specific regular expression pattern checks that the received parameter value:

* `^`: starts with the following characters, doesn't have characters before.

    assertEquals("&lt;tab&gt;", xmlEscaper.escape("<tab>"));

    // Test all non-escaped ASCII characters.
    String s =
        "!@#$%^*()_+=-/?\\|]}[{,.;:"
            + "abcdefghijklmnopqrstuvwxyz"
            + "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
            + "1234567890";
    assertEquals(s, xmlEscaper.escape(s));

    // Test ASCII control characters.
    for (char ch = 0; ch < 0x20; ch++) {
      if (ch == '\t' || ch == '\n' || ch == '\r') {

"backtick"

    The character «`»
    Unicode U+0060 (GRAVE ACCENT)

"single backtick"

    A single backtick – «`»

"triple backticks"

    Three backticks in a row – «```»

"neutral double quote"

    The character «"»
    Unicode U+0022 (QUOTATION MARK)

"neutral single quote"

    The character «'»
    Unicode U+0027 (APOSTROPHE)

"English double typographic quotes"

    The characters «“» and «”»

    @Test
    public void testParseQueryWithSpecialCharacters() {
        // Test query with special characters
        String query = "test+query-search";
        String field = "content";
        String[] keywords = SuggestUtil.parseQuery(query, field);
        assertNotNull(keywords);
        // Parser should handle special characters
    }

    @Test
    public void testGetTermQueryListWithNull() {

    }

    /**
     * SAX event handler called to process character data between XML elements.
     * Accumulates text content in a buffer for later processing when the element ends.
     *
     * @param ch the characters from the XML document
     * @param start the start position in the character array
     * @param length the number of characters to use from the character array

    assert response.json() == {
        "detail": [
            {
                "type": "string_too_short",
                "loc": ["query", "q"],
                "msg": "String should have at least 3 characters",
                "input": "qu",
                "ctx": {"min_length": 3},
            }
        ]
    }


def test_query_params_str_validations_q_too_long(client: TestClient):