for-loop.js - mozsearch

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/*

 * Any copyright is dedicated to the Public Domain.

 * http://creativecommons.org/licenses/publicdomain/

*/

var gTestfile = "for-loop.js";

//-----------------------------------------------------------------------------

var BUGNUMBER = 985733;

var summary =

  "ES6 for-loop semantics for for(;;) loops whose heads contain lexical "

  "declarations";

print(BUGNUMBER + ": " + summary);

/**************

 * BEGIN TEST *

 **************/

function isError(code, type)

try

    Function(code);

    throw new Error("didn't throw");

  catch (e)

    assertEq(e instanceof type, true,

             "unexpected error for `" + code + "`: got " + e);

function isOK(code)

  Function(code);

isError("for (const x; ; ) ;", SyntaxError);

isError("for (const x = 5, y; ; ) ;", SyntaxError);

isError("for (const [z]; ; ) ;", SyntaxError);

//isError("for (const [z, z]; ; ) ;", SyntaxError);

//isError("for (const [z, z] = [0, 1]; ; ) ;", SyntaxError);

isOK("for (let x; ; ) ;");

isOK("for (let x = 5, y; ; ) ;");

// I'm fairly sure this is supposed to work: the negative-lookahead rules in

// IterationStatement ensure that |for (let| *always* is a loop header starting

// with a lexical declaration.  But I'm not 100% certain, so these tests might

// need to be fixed when we implement the negative-lookahead restrictions.

isOK("for (let [z] = [3]; ; ) ;");

isError("for (let [z, z]; ; ) ;", SyntaxError); // because missing initializer

isError("for (let [z, z] = [0, 1]; ; ) ;", SyntaxError);

// A for-loop with lexical declarations, with a mixture of bindings that are and

// aren't aliased.  (The mixture stress-tests any code that incorrectly assumes

// all bindings are aliased.)

var funcs = [];

for (let [i, j, k] = [0, 1, 2]; i < 10; i++)

  funcs.push(() => i);

assertEq(funcs[0](), 0);

assertEq(funcs[1](), 1);

assertEq(funcs[2](), 2);

assertEq(funcs[3](), 3);

assertEq(funcs[4](), 4);

assertEq(funcs[5](), 5);

assertEq(funcs[6](), 6);

assertEq(funcs[7](), 7);

assertEq(funcs[8](), 8);

assertEq(funcs[9](), 9);

var outer = "OUTER V IGNORE";

var save;

for (let outer = (save = function() { return outer; }); ; )

  break;

assertEq(save(), save);

var funcs = [];

function t(i, name, expect)

  assertEq(funcs[i].name, name);

  assertEq(funcs[i](), expect);

if (save() !== "OUTER V IGNORE")

  var v = "OUTER V IGNORE";

  var i = 0;

  for (let v = (funcs.push(function init() { return v; }),

0);

      v = (funcs.push(function test() { return v; }),

           v + 1);

      v = (funcs.push(function incr() { return v; }),

           v + 1))

    v = (funcs.push(function body() { return v; }),

         v + 1);

    i++;

    if (i >= 3)

      break;

  t(0, "init", 0);

  t(1, "test", 2);

  t(2, "body", 2);

  t(3, "incr", 5);

  t(4, "test", 5);

  t(5, "body", 5);

  t(6, "incr", 8);

  t(7, "test", 8);

  t(8, "body", 8);

  assertEq(funcs.length, 9);

/******************************************************************************/

if (typeof reportCompare === "function")

  reportCompare(true, true);

print("Tests complete");