test/mjsunit/harmony/block-let-declaration.js

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// Flags: --harmony-block-scoping

// Test let declarations in various settings.

// Global
let x;
let y = 2;

// Block local
{
  let y;
  let x = 3;
}

assertEquals(undefined, x);
assertEquals(2,y);

if (true) {
  let y;
  assertEquals(undefined, y);
}

function TestLocalThrows(str, expect) {
  assertThrows("(function(){" + str + "})()", expect);
}

function TestLocalDoesNotThrow(str) {
  assertDoesNotThrow("(function(){" + str + "})()");
}

// Unprotected statement
TestLocalThrows("if (true) let x;", SyntaxError);
TestLocalThrows("do let x; while (false)", SyntaxError);
TestLocalThrows("while (false) let x;", SyntaxError);

TestLocalDoesNotThrow("if (true) var x;");
TestLocalDoesNotThrow("do var x; while (false)");
TestLocalDoesNotThrow("while (false) var x;");