Detect conflicting variable bindings in harmony mode.

test/mjsunit/harmony/block-conflicts.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
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --harmony-block-scoping
+
+// Test for conflicting variable bindings.
+
+function CheckException(e) {
+  var string = e.toString();
+  assertTrue(string.indexOf("has already been declared") >= 0 ||
+             string.indexOf("redeclaration") >= 0);  return 'Conflict';
+}
+
+
+function TestFunction(s,e) {
+  try {
+    return eval("(function(){" + s + ";return " + e + "})")();
+  } catch (x) {
+    return CheckException(x);
+  }
+}
+
+
+function TestBlock(s,e) {
+  try {
+    return eval("(function(){ if (true) { " + s + "; }; return " + e + "})")();
+  } catch (x) {
+    return CheckException(x);
+  }
+}
+
+function TestAll(expected,s,opt_e) {
+  var e = "";
+  var msg = s;
+  if (opt_e) { e = opt_e; msg += "; " + opt_e; }
+  assertEquals(expected, TestFunction(s,e), "function:'" + msg + "'");
+  assertEquals(expected, TestBlock(s,e), "block:'" + msg + "'");
+}
+
+
+function TestConflict(s) {
+  TestAll('Conflict', s);
+  TestAll('Conflict', 'eval("' + s + '")');
+}
+
+
+function TestNoConflict(s) {
+  TestAll('NoConflict', s, "'NoConflict'");
+  TestAll('NoConflict', 'eval("' + s + '")', "'NoConflict'");
+}
+
+var letbinds = [ "let x",
+                 "let x = 0",
+                 "let x = undefined",
+                 "function x() { }",
+                 "let x = function() {}",
+                 "let x, y",
+                 "let y, x",
+                 ];
+var varbinds = [ "var x",
+                 "var x = 0",
+                 "var x = undefined",
+                 "var x = function() {}",
+                 "var x, y",
+                 "var y, x",
+                 ];
+
+
+for (var l = 0; l < letbinds.length; ++l) {
+  // Test conflicting let/var bindings.
+  for (var v = 0; v < varbinds.length; ++v) {
+    // Same level.
+    TestConflict(letbinds[l] +'; ' + varbinds[v]);
+    TestConflict(varbinds[v] +'; ' + letbinds[l]);
+    // Different level.
+    TestConflict(letbinds[l] +'; {' + varbinds[v] + '; }');
+    TestConflict('{ ' + varbinds[v] +'; }' + letbinds[l]);
+  }
+
+  // Test conflicting let/let bindings.
+  for (var k = 0; k < letbinds.length; ++k) {
+    // Same level.
+    TestConflict(letbinds[l] +'; ' + letbinds[k]);
+    TestConflict(letbinds[k] +'; ' + letbinds[l]);
+    // Different level.
+    TestNoConflict(letbinds[l] +'; { ' + letbinds[k] + '; }');
+    TestNoConflict('{ ' + letbinds[k] +'; } ' + letbinds[l]);
+  }
+
+  // Test conflicting parameter/let bindings.
+  TestConflict('(function (x) { ' + letbinds[l] + '; })()');
+}
+
+// Test conflicting catch/var bindings.
+for (var v = 0; v < varbinds.length; ++v) {
+  TestConflict('try {} catch (x) { ' + varbinds[v] + '; }');
+}
+
+// Test conflicting parameter/var bindings.
+for (var v = 0; v < varbinds.length; ++v) {
+  TestConflict('(function (x) { ' + varbinds[v] + '; })()');
+}