prev := runeZero
	hasLeadingPercent := false
	patLen := len([]rune(pattern))
	for i, r := range pattern {
		if i > 0 && prev == escape {
			switch r {
			case percent, escape, underscore:
				s = append(s, r)
				prev = r
				if r == escape {
					prev = runeZero
				}
			default:
				return false, errMalformedEscapeSequence
			}
			continue
		}

		prev = r

		var ok bool
		switch r {
		case percent:

    }
    return result;
  }

  /**
   * Convert this builder into a char escaper which is just a decorator around the underlying array
   * of replacement char[]s.
   *
   * @return an escaper that escapes based on the underlying array.
   */
  public Escaper toEscaper() {
    return new CharArrayDecorator(toArray());
  }

      "\0abyz\u0080\u0100\u0800\u1000ABYZ\uffff" + SMALLEST_SURROGATE + "0189" + LARGEST_SURROGATE;

  // Escapes nothing
  private static final UnicodeEscaper NOP_ESCAPER =
      new UnicodeEscaper() {
        @Override
        protected char @Nullable [] escape(int c) {
          return null;
        }
      };

  // Escapes everything except [a-zA-Z0-9]
  private static final UnicodeEscaper SIMPLE_ESCAPER =

 * the License.
 */

package com.google.common.xml;

import com.google.common.annotations.GwtCompatible;
import com.google.common.escape.Escaper;
import com.google.common.escape.Escapers;

/**
 * {@code Escaper} instances suitable for strings to be included in XML attribute values and
 * elements' text contents. When possible, avoid manual escaping by using templating systems and

from a2wsgi import WSGIMiddleware
from fastapi import FastAPI
from flask import Flask, request
from markupsafe import escape

flask_app = Flask(__name__)


@flask_app.route("/")
def flask_main():
    name = request.args.get("name", "World")
    return f"Hello, {escape(name)} from Flask!"


app = FastAPI()


@app.get("/v2")
def read_main():
    return {"message": "Hello World"}

    assertUnicodeEscaping(e, "%F4%8F%BF%BF", '\uDBFF', '\uDFFF');

    // simple string tests
    assertThat(e.escape("")).isEqualTo("");
    assertThat(e.escape("safestring")).isEqualTo("safestring");
    assertThat(e.escape("embedded\0null")).isEqualTo("embedded%00null");
    assertThat(e.escape("max\uffffchar")).isEqualTo("max%EF%BF%BFchar");
  }

  /** Tests the various ways that the space character can be handled */

    assertUnicodeEscaping(e, "%F4%8F%BF%BF", '\uDBFF', '\uDFFF');

    assertThat(e.escape("")).isEqualTo("");
    assertThat(e.escape("safestring")).isEqualTo("safestring");
    assertThat(e.escape("embedded\0null")).isEqualTo("embedded%00null");
    assertThat(e.escape("max\uffffchar")).isEqualTo("max%EF%BF%BFchar");
  }

  // Helper to assert common expected behaviour of uri escapers.

    assertUnicodeEscaping(e, "%F4%8F%BF%BF", '\uDBFF', '\uDFFF');

    assertThat(e.escape("")).isEqualTo("");
    assertThat(e.escape("safestring")).isEqualTo("safestring");
    assertThat(e.escape("embedded\0null")).isEqualTo("embedded%00null");
    assertThat(e.escape("max\uffffchar")).isEqualTo("max%EF%BF%BFchar");
  }

  // Helper to assert common expected behaviour of uri escapers.

  private Escapers() {}

  /**
   * Returns an {@link Escaper} that does no escaping, passing all character data through unchanged.
   */
  public static Escaper nullEscaper() {
    return NULL_ESCAPER;
  }

  // An Escaper that efficiently performs no escaping.
  // Extending CharEscaper (instead of Escaper) makes Escapers.compose() easier.
  private static final Escaper NULL_ESCAPER =
      new CharEscaper() {
        @Override

            }

            @Override
            public boolean hasConditionQuery() {
                return conditions != null && !conditions.isEmpty();
            }

        }).escape(escape).build();
    }

    // Additional test methods for improved coverage

    @Test
    public void test_conditions_filetype() {
        final String k = "filetype";