LibTest/core/Symbol/Symbol_A02_t03.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 const Symbol(String name)
/// Constructs a new Symbol representing the provided name.
///
/// Symbols created from equal name strings are themselves equal. If the symbols
/// are created using const, symbols with the same name strings are
/// canonicalized and identical.
///
/// Some name strings create symbols which can also be created using a symbol
/// literal, or be implicitly created while running Dart programs, for example
/// through Object.noSuchMethod.
///
/// If name is a single Dart identifier that does not start with an underscore,
/// or it is a qualified identifier (multiple identifiers separated by .s), or
/// it is the name of a user definable operator different from unary- (one of
/// "+", "-", "*", "/", "%", "~/", "&", "|", "^", "~", "<<", ">>", ">>>", "<",
/// "<=", ">", ">=", "==", "[]", or "[]="), then the result of Symbol(name) is
/// equal to the symbol literal created by prefixing # to the contents of name,
/// and const Symbol(name) is identical to that symbol literal.
/// That is #foo == Symbol("foo") and identical(#foo, const Symbol("foo")).
///
/// If name is a single identifier that does not start with an underscore
/// followed by a =, then the symbol is a setter name, and can be equal to the
/// Invocation.memberName in an Object.noSuchMethod invocation.
///
/// Private symbol literals, like #_foo, cannot be created using the symbol
/// constructor. A symbol like const Symbol("_foo") is not equal to any symbol
/// literal, or to any source name symbol introduced by noSuchMethod.
///
/// assert(Symbol("foo") == Symbol("foo"));
/// assert(Symbol("foo") == #foo);
/// assert(identical(const Symbol("foo"), const Symbol("foo")));
/// assert(identical(const Symbol("foo"), #foo));
/// assert(Symbol("[]=") == #[]=]);
/// assert(identical(const Symbol("[]="), #[]=));
/// assert(Symbol("foo.bar") == #foo.bar);
/// assert(identical(const Symbol("foo.bar"), #foo.bar));
/// The created instance overrides Object.==.
///
/// @description Checks that symbols for operators can be created.
/// @author ilya, sgrekhov@unipro.ru

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

main() {
  Expect.equals(#~, new Symbol('~'));
  Expect.isFalse(identical(#~, new Symbol('~')));
  Expect.equals(#==, new Symbol('=='));
  Expect.isFalse(identical(#==, new Symbol('==')));
  Expect.equals(#[], new Symbol('[]'));
  Expect.isFalse(identical(#[], new Symbol('[]')));
  Expect.equals(#[]=, new Symbol('[]='));
  Expect.isFalse(identical(#[]=, new Symbol('[]=')));

  Expect.equals(#*, new Symbol('*'));
  Expect.isFalse(identical(#*, new Symbol('*')));
  Expect.equals(#/, new Symbol('/'));
  Expect.isFalse(identical(#/, new Symbol('/')));
  Expect.equals(#%, new Symbol('%'));
  Expect.isFalse(identical(#%, new Symbol('%')));
  Expect.equals(#~/, new Symbol('~/'));
  Expect.isFalse(identical(#~/, new Symbol('~/')));

  Expect.equals(#+, new Symbol('+'));
  Expect.isFalse(identical(#+, new Symbol('+')));
  Expect.equals(#-, new Symbol('-'));
  Expect.isFalse(identical(#-, new Symbol('-')));

  Expect.equals(#<<, new Symbol('<<'));
  Expect.isFalse(identical(#<<, new Symbol('<<')));
  Expect.equals(#>>, new Symbol('>>'));
  Expect.isFalse(identical(#>>, new Symbol('>>')));
  Expect.equals(#>>>, new Symbol('>>>'));
  Expect.isFalse(identical(#>>>, new Symbol('>>>')));

  Expect.equals(#<, new Symbol('<'));
  Expect.isFalse(identical(#<, new Symbol('<')));
  Expect.equals(#<=, new Symbol('<='));
  Expect.isFalse(identical(#<=, new Symbol('<=')));
  Expect.equals(#>, new Symbol('>'));
  Expect.isFalse(identical(#>, new Symbol('>')));
  Expect.equals(#>=, new Symbol('>='));
  Expect.isFalse(identical(#>=, new Symbol('>=')));

  Expect.equals(#&, new Symbol('&'));
  Expect.isFalse(identical(#&, new Symbol('&')));
  Expect.equals(#^, new Symbol('^'));
  Expect.isFalse(identical(#^, new Symbol('^')));
  Expect.equals(#|, new Symbol('|'));
  Expect.isFalse(identical(#|, new Symbol('|')));
}