[es6] parse destructuring assignment

test/cctest/test-parsing.cc

 // Copyright 2012 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
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@@ skipping 6526 matching lines @@
       "[yield]",
       "{ x : yield }",
       NULL};
     // clang-format on
     RunParserSyncTest(context_data, data, kError, NULL, 0, always_flags,
                       arraysize(always_flags));
   }
 }
 
 
+TEST(DestructuringAssignmentPositiveTests) {
+  i::FLAG_harmony_destructuring = true;
+  i::FLAG_harmony_computed_property_names = true;
+
+  const char* context_data[][2] = {
+      {"'use strict'; let x, y, z; (", " = {});"},
+      {"var x, y, z; (", " = {});"},
+      {"'use strict'; let x, y, z; for (x in ", " = {});"},
+      {"'use strict'; let x, y, z; for (x of ", " = {});"},
+      {"var x, y, z; for (x in ", " = {});"},

[arv (Not doing code reviews), 2015/06/05 18:45:26]

This was not what I had in mind. Here is an example of what I had in mind

for ({length} in {x: 1, y: 2}) {}

and similarly for for-of

[caitp (gmail), 2015/06/05 19:00:20]

They're both valid, but we may be reporting an error if the LHS of for-loops
isn't a valid identifier, I think tests for the LHS bindings need to happen in a
followup.

For the RHS, since those are assignment expressions, if destructuring assignment
happens there it should  be allowed

+      {"var x, y, z; for (x of ", " = {});"},
+      {NULL, NULL}};
+
+  // clang-format off
+  const char* data[] = {
+    "x",
+    "{ x : y }",
+    "{ x : y = 1 }",
+    "{ x }",
+    "{ x, y, z }",
+    "{ x = 1, y: z, z: y }",
+    "{x = 42, y = 15}",
+    "[x]",
+    "[x = 1]",
+    "[x,y,z]",
+    "[x, y = 42, z]",
+    "{ x : x, y : y }",
+    "{ x : x = 1, y : y }",
+    "{ x : x, y : y = 42 }",
+    "[]",
+    "{}",
+    "[{x:x, y:y}, [,x,z,]]",
+    "[{x:x = 1, y:y = 2}, [z = 3, z = 4, z = 5]]",
+    "[x,,y]",
+    "[(x),,(y)]",
+    "[(x)]",
+    "{42 : x}",
+    "{42 : x = 42}",
+    "{42e-2 : x}",
+    "{42e-2 : x = 42}",
+    "{'hi' : x}",
+    "{'hi' : x = 42}",
+    "{var: x}",
+    "{var: x = 42}",
+    "{var: (x) = 42}",
+    "{[x] : z}",
+    "{[1+1] : z}",
+    "{[1+1] : (z)}",
+    "{[foo()] : z}",
+    "{[foo()] : (z)}",
+    "{[foo()] : foo().bar}",
+    "{[foo()] : foo()['bar']}",
+    "{[foo()] : this.bar}",
+    "{[foo()] : this['bar']}",
+    "{[foo()] : 'foo'.bar}",
+    "{[foo()] : 'foo'['bar']}",
+    "[...x]",
+    "[x,y,...z]",
+    "[x,,...z]",
+    "{ x: y } = z",
+    "[x, y] = z",
+    "{ x: y } = { z }",
+    "[x, y] = { z }",
+    "{ x: y } = [ z ]",
+    "[x, y] = [ z ]",
+    NULL};
+  // clang-format on
+  static const ParserFlag always_flags[] = {kAllowHarmonyObjectLiterals,
+                                            kAllowHarmonyComputedPropertyNames,
+                                            kAllowHarmonyDestructuring};
+  RunParserSyncTest(context_data, data, kSuccess, NULL, 0, always_flags,
+                    arraysize(always_flags));
+}
+
+
+TEST(DestructuringAssignmentNegativeTests) {
+  i::FLAG_harmony_destructuring = true;
+  i::FLAG_harmony_computed_property_names = true;
+
+  const char* context_data[][2] = {
+      {"'use strict'; let x, y, z; (", " = {});"},
+      {"var x, y, z; (", " = {});"},
+      {"'use strict'; let x, y, z; for (x in ", " = {});"},
+      {"'use strict'; let x, y, z; for (x of ", " = {});"},
+      {"var x, y, z; for (x in ", " = {});"},
+      {"var x, y, z; for (x of ", " = {});"},
+      {NULL, NULL}};
+
+  // clang-format off
+  const char* data[] = {
+    "{ x : ++y }",
+    "{ x : y * 2 }",
+    "{ ...x }",
+    "{ get x() {} }",
+    "{ set x() {} }",
+    "{ x: y() }",
+    "{ this }",
+    "{ x: this }",
+    "{ x: this = 1 }",
+    "{ super }",
+    "{ x: super }",
+    "{ x: super = 1 }",
+    "{ new.target }",
+    "{ x: new.target }",
+    "{ x: new.target = 1 }",
+    "[x--]",
+    "[--x = 1]",
+    "[x()]",
+    "[this]",
+    "[this = 1]",
+    "[new.target]",
+    "[new.target = 1]",
+    "[super]",
+    "[super = 1]",
+    "[function f() {}]",
+    "[50]",
+    "[(50)]",
+    "[(function() {})]",
+    "[(foo())]",
+    "{ x: 50 }",
+    "{ x: (50) }",
+    "['str']",
+    "{ x: 'str' }",
+    "{ x: ('str') }",
+    "{ x: (foo()) }",
+    "{ x: (function() {}) }",
+    "{ x: y } = 'str'",
+    "[x, y] = 'str'",
+    NULL};
+  // clang-format on
+  static const ParserFlag always_flags[] = {kAllowHarmonyObjectLiterals,
+                                            kAllowHarmonyComputedPropertyNames,
+                                            kAllowHarmonyDestructuring};
+  RunParserSyncTest(context_data, data, kError, NULL, 0, always_flags,
+                    arraysize(always_flags));
+}
+
+
 TEST(DestructuringDisallowPatternsInForVarIn) {
   i::FLAG_harmony_destructuring = true;
   static const ParserFlag always_flags[] = {kAllowHarmonyDestructuring};
   const char* context_data[][2] = {
       {"", ""}, {"function f() {", "}"}, {NULL, NULL}};
   // clang-format off
   const char* error_data[] = {
     "for (var {x} = {} in null);",
     "for (var {x} = {} of null);",
     "for (let x = {} in null);",
@@ skipping 51 matching lines @@
     "[a, ...]",
     "[..., ]",
     "[..., ...]",
     "[ (...a)]",
     NULL};
   // clang-format on
   static const ParserFlag always_flags[] = {kAllowHarmonySpreadArrays};
   RunParserSyncTest(context_data, data, kError, NULL, 0, always_flags,
                     arraysize(always_flags));
 }