Add parsing for type aliases

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 7819 matching lines @@
   static const ParserFlag always_flags[] = {kAllowTypes};
   RunParserSyncTest(untyped_context_data, correct_data, kError, NULL, 0,
                     always_flags, arraysize(always_flags));
   RunParserSyncTest(typed_context_data, correct_data, kSuccess, NULL, 0,
                     always_flags, arraysize(always_flags));
   RunParserSyncTest(untyped_context_data, error_data, kError, NULL, 0,
                     always_flags, arraysize(always_flags));
   RunParserSyncTest(typed_context_data, error_data, kError, NULL, 0,
                     always_flags, arraysize(always_flags));
 }
+
+TEST(TypedModeTypeAliases) {
+  const char* untyped_context_data[][2] = {{"", ""}, {NULL, NULL}};
+  const char* typed_context_data[][2] = {{"'use types'; ", ""}, {NULL, NULL}};
+
+  const char* correct_data[] = {
+    "type NumArray = number[]",
+    "type Fun = (x: number) => number",
+    "type Tree<A> = A | Tree<A>[]",
+    NULL
+  };
+
+  const char* error_data[] = {
+    "type Err<> = number",

[rossberg, 2016/04/18 09:27:43]

How about "type", with no identifier following.

[nickie, 2016/04/19 13:52:51]

Done.

We agreed that "type = number" should parse as an assignment of identifier
"number" to identifier "type", even in typed mode.  I'm making the necessary
changes and adding the test.

For a valid type alias declaration in typed mode, the contextual keyword "type"
must be followed by an identifier.  As in the case of "let", this will be so
even if there is a line terminator in between.

+    "type Err",
+    "type Err =",
+    "type Err = ()",
+    NULL
+  };
+
+  static const ParserFlag always_flags[] = {kAllowTypes};
+  RunParserSyncTest(untyped_context_data, correct_data, kError, NULL, 0,
+                    always_flags, arraysize(always_flags));
+  RunParserSyncTest(typed_context_data, correct_data, kSuccess, NULL, 0,
+                    always_flags, arraysize(always_flags));
+  RunParserSyncTest(untyped_context_data, error_data, kError, NULL, 0,
+                    always_flags, arraysize(always_flags));
+  RunParserSyncTest(typed_context_data, error_data, kError, NULL, 0,
+                    always_flags, arraysize(always_flags));
+}