LibTest/core/RegExp/Pattern_semantics/firstMatch_Assertion_A03_t01.dart

// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

/// @assertion 15.10.2.6: The production Assertion :: \ b evaluates by returning
/// an internal AssertionTester closure that takes a State argument x and
/// performs the following:
///   <ol>
///   <li>Let e be x's endIndex.</li>
///   <li>Call IsWordChar(e-1) and let a be the Boolean result.</li>
///   <li>Call IsWordChar(e) and let b be the Boolean result.</li>
///   <li>If a is true and b is false, return true.</li>
///   <li>If a is false and b is true, return true.</li>
///   <li>Return false. </li>
///   </ol>
/// The abstract operation IsWordChar(e) returns true if and only if its argument
/// is between -1 and InputLength (exclusive) and the input character at the
/// position specified by e is one of: latin letters (both cases), arabic
/// numerals or the underscore.
/// @description Checks that the \b assertion is interpreted correctly.
/// @3rdparty sputnik-v1:S15.10.2.6_A3_T1.js-S15.10.2.6_A3_T15.js
/// @author rodionov

import "../../../../Utils/expect.dart";
 

main() {
  check(r"\bp", "pilot\nsoviet robot\topenoffice",  matchPos: 0);
  check(r"ot\b", "pilot\nsoviet robot\topenoffice", matchPos: 3);
  checkNeg(r"\bot", "pilot\nsoviet robot\topenoffice");
  check(r"\bso", "pilot\nsoviet robot\topenoffice", matchPos: 6);
  checkNeg(r"so\b", "pilot\nsoviet robot\topenoffice");
  check(r"[^o]t\b", "pilOt\nsoviet robot\topenoffice", matchPos: 3);
  check(r"[^o]t\b", "pilOt\nsoviet robot\topenoffice", caseSensitive: false,
      matchPos: 10);
  check(r"\bro", "pilot\nsoviet robot\topenoffice", matchPos: 13);
  checkNeg(r"r\b", "pilot\nsoviet robot\topenoffice");
  check(r"\brobot\b", "pilot\nsoviet robot\topenoffice", matchPos: 13);
  check(r"\b\w{5}\b", "pilot\nsoviet robot\topenoffice", matchPos: 0);
  check(r"\bop", "pilot\nsoviet robot\topenoffice", matchPos: 19);
  checkNeg(r"op\b", "pilot\nsoviet robot\topenoffice");
  check(r"e\b", "pilot\nsoviet robot\topenoffic\u0065", matchPos: 28);
  checkNeg(r"\be", "pilot\nsoviet robot\topenoffic\u0065");
}

void check(String pattern, String str, {bool multiLine: false,
    bool caseSensitive: true, int matchPos: -1}) {
  RegExp re = new RegExp(pattern, multiLine: multiLine,
      caseSensitive: caseSensitive);
  Match? fm = re.firstMatch(str);
  Expect.isNotNull(fm, "\"$pattern\" !~ \"$str\"");
  if(matchPos >= 0) {
    Expect.equals(matchPos, fm?.start);
  }
}

void checkNeg(String pattern, String str,
    {bool multiLine: false, bool caseSensitive: true}) {
  RegExp re = new RegExp(
      pattern, multiLine: multiLine, caseSensitive: caseSensitive);
  Expect.isNull(re.firstMatch(str), "\"$pattern\" ~ \"$str\"");
}