* element content or {@link #xmlAttributeEscaper} in attribute values.
   *
   * <p>This escaper substitutes {@code 0xFFFD} for non-whitespace control characters and the
   * character values {@code 0xFFFE} and {@code 0xFFFF} which are not permitted in XML. For more
   * detail see section <a href="http://www.w3.org/TR/2008/REC-xml-20081126/#charsets">2.2</a> of

    val headers =
      Headers
        .Builder()
        .add("foo: bar")
        .add(" foo: baz") // Name leading whitespace is trimmed.
        .add("foo : bak") // Name trailing whitespace is trimmed.
        .add("\tkey\t:\tvalue\t") // '\t' also counts as whitespace
        .add("ping:  pong  ") // Value whitespace is trimmed.
        .add("kit:kat") // Space after colon is not required.
        .build()

            return Stream.of(
                    Arguments.of(null, "null version"),
                    Arguments.of("", "empty version"),
                    Arguments.of("   ", "whitespace-only version"),
                    Arguments.of("4", "incomplete version (major only)"),
                    Arguments.of("4.0", "incomplete version (major.minor only)"),

        while (st.hasMoreElements()) {
            list.add(st.nextElement().toString());
        }
        return list.toArray(new String[list.size()]);
    }

    /**
     * Removes whitespace from the left side of the string.
     *
     * @param text
     *            The text to trim
     * @return The resulting string
     */
    public static final String ltrim(final String text) {

    /**
     * Process a single line: remove comments, trim whitespace, and replace placeholders.
     */
    private static String processLine(String line, String mavenProjectBasedir) {
        // Remove comments
        int commentIndex = line.indexOf('#');
        if (commentIndex >= 0) {
            line = line.substring(0, commentIndex);
        }

        // Trim whitespace
        line = line.trim();

Fixer tool expects comments that follow specific pattern:

- For hash-style comments: comment starts with `# ` (hash following by whitespace) in the beginning of the string or after a whitespace.
- For slash-style comments: comment starts with `// ` (two slashes following by whitespace) in the beginning of the string or after a whitespace.

If comment doesn't follow this pattern, fixer tool will not preserve it.

```python
#Function declaration

                    }
                    ip = (ip << 8) + b;
                }
                while (i < data.length && Character.isWhitespace(data[i])) {
                    i++;
                }
                j = i;
                while (j < data.length && !Character.isWhitespace(data[j])) {
                    j++;
                }

                name = new Name(tc.getConfig(), line.substring(i, j), 0x20, null);

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.io;

import static com.google.common.base.CharMatcher.whitespace;
import static com.google.common.truth.Truth.assertThat;
import static java.nio.charset.StandardCharsets.US_ASCII;
import static java.nio.charset.StandardCharsets.UTF_8;
import static org.junit.Assert.assertThrows;

                "word1\n" + "  \n" + // whitespace line (may be treated as content)
                "# Another comment\n" + "word2\n";

        // Write content to test file
        writeTestFile(content);

        // Reload and verify
        protwordsFile.reload(null);

        PagingList<ProtwordsItem> result = protwordsFile.selectList(0, 10);
        // Whitespace-only lines may be treated as entries

        return new CopyOptions().excludeNull();
    }

    /**
     * Returns a {@link CopyOptions} that excludes properties with whitespace values from the operation.
     *
     * @return A {@link CopyOptions} that excludes properties with whitespace values from the operation.
     * @see CopyOptions#excludeWhitespace()
     */
    public static CopyOptions excludeWhitespace() {