Temporal dead zone behaviour for let bindings.

test/mjsunit/harmony/block-let-crankshaft.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
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+//
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+//
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+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --harmony-block-scoping --allow-natives-syntax
+
+// Test that temporal dead zone semantics for function and block scoped
+// ket bindings are handled by the optimizing compiler.
+
+function f(x, b) {
+  let y = (b ? y : x) + 42;
+  return y;
+}
+
+function g(x, b) {
+  {
+    let y = (b ? y : x) + 42;
+    return y;
+  }
+}
+
+for (var i=0; i<10; i++) {
+  f(i, false);
+  g(i, false);
+}
+
+%OptimizeFunctionOnNextCall(f);
+%OptimizeFunctionOnNextCall(g);
+
+try {
+  f(42, true);
+} catch (e) {

[fschneider, 2011/08/30 06:58:40]

Use assertThrows to test if there actually was an exception thrown.

+  assertInstanceof(e, ReferenceError);
+}
+
+try {
+  g(42, true);

[fschneider, 2011/08/30 06:58:40]

Also assertThrows here.

+} catch (e) {
+  assertInstanceof(e, ReferenceError);
+}