LibTest/core/Symbol/Symbol_A02_t02.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.identical(#~, const Symbol('~'));
  Expect.identical(#==, const Symbol('=='));
  Expect.identical(#[], const Symbol('[]'));
  Expect.identical(#[]=, const Symbol('[]='));

  Expect.identical(#*, const Symbol('*'));
  Expect.identical(#/, const Symbol('/'));
  Expect.identical(#%, const Symbol('%'));
  Expect.identical(#~/, const Symbol('~/'));

  Expect.identical(#+, const Symbol('+'));
  Expect.identical(#-, const Symbol('-'));

  Expect.identical(#<<, const Symbol('<<'));
  Expect.identical(#>>, const Symbol('>>'));
  Expect.identical(#>>>, const Symbol('>>>'));

  Expect.identical(#<, const Symbol('<'));
  Expect.identical(#<=, const Symbol('<='));
  Expect.identical(#>, const Symbol('>'));
  Expect.identical(#>=, const Symbol('>='));

  Expect.identical(#&, const Symbol('&'));
  Expect.identical(#^, const Symbol('^'));
  Expect.identical(#|, const Symbol('|'));
}