Block scoped const variables.

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

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 43 matching lines @@
 function TestAll(s) {
   TestBlockLocal(s);
   TestFunctionLocal(s);
 }
 
 // Use before initialization in declaration statement.
 TestAll('let x = x + 1');
 TestAll('let x = x += 1');
 TestAll('let x = x++');
 TestAll('let x = ++x');
+TestAll('const x = x + 1');
 
 // Use before initialization in prior statement.
 TestAll('x + 1; let x;');
 TestAll('x = 1; let x;');
 TestAll('x += 1; let x;');
 TestAll('++x; let x;');
 TestAll('x++; let x;');
+TestAll('let y = x; const x = 1;');
 
 TestAll('f(); let x; function f() { return x + 1; }');
 TestAll('f(); let x; function f() { x = 1; }');
 TestAll('f(); let x; function f() { x += 1; }');
 TestAll('f(); let x; function f() { ++x; }');
 TestAll('f(); let x; function f() { x++; }');
+TestAll('f(); const x = 1; function f() { return x; }');
 
 TestAll('f()(); let x; function f() { return function() { return x + 1; } }');
 TestAll('f()(); let x; function f() { return function() { x = 1; } }');
 TestAll('f()(); let x; function f() { return function() { x += 1; } }');
 TestAll('f()(); let x; function f() { return function() { ++x; } }');
 TestAll('f()(); let x; function f() { return function() { x++; } }');
+TestAll('f()(); const x = 1; function f() { return function() { return x; } }');
 
 // Use before initialization with a dynamic lookup.
 TestAll('eval("x + 1;"); let x;');
 TestAll('eval("x = 1;"); let x;');
 TestAll('eval("x += 1;"); let x;');
 TestAll('eval("++x;"); let x;');
 TestAll('eval("x++;"); let x;');
+TestAll('eval("x"); const x = 1;');
 
 // Use before initialization with check for eval-shadowed bindings.
 TestAll('function f() { eval("var y = 2;"); x + 1; }; f(); let x;');
 TestAll('function f() { eval("var y = 2;"); x = 1; }; f(); let x;');
 TestAll('function f() { eval("var y = 2;"); x += 1; }; f(); let x;');
 TestAll('function f() { eval("var y = 2;"); ++x; }; f(); let x;');
 TestAll('function f() { eval("var y = 2;"); x++; }; f(); let x;');
 
 // Test that variables introduced by function declarations are created and
 // initialized upon entering a function / block scope.
@@ skipping 32 matching lines @@
   }
   assertEquals(1, m());
 
   try {
     throw 2;
   } catch(b) {
     n = h;
     function h() {
       return b + c;
     }
-    let b = 3;
+    let c = 3;
   }
   assertEquals(5, n());
+
+  {
+    o = i;
+    function i() {
+      return d;
+    }
+    let d = 4;
+  }
+  assertEquals(4, o());
+
+  try {
+    throw 5;
+  } catch(e) {
+    p = j;
+    function j() {
+      return e + f;
+    }
+    let f = 6;
+  }
+  assertEquals(11, p());
 }
+f2();
 
 // Test that resolution of let bound variables works with scopes that call eval.
 function outer() {
   function middle() {
     function inner() {
       return x;
     }
     eval("1 + 1");
     return x + inner();
   }
 
   let x = 1;
   return middle();
 }
 
 assertEquals(2, outer());