Breaking: Support unique symbol (fixes #426)

[azz]

This changes captures TSTypeOperator and treats it like a unary operator. It breaks keyof foo and adds support for unique symbol. The TSTypeOperator node's typeAnnotation parameter is now the TSTypeReference, rather than a TSTypeAnnotation which has a TSTypeReference. (more direct), this is to align with babylon.

@@ -30,11 +30,12 @@
                "start": Object {
                  "column": 9,
                  "line": 1,
                },
              },
-             "operator": 140,
+             "operator": "unique",
+             "prefix": true,
              "range": Array [
                9,
                22,
              ],
              "type": "TSTypeOperator",
@@ -43,36 +44,19 @@
                  "end": Object {
                    "column": 22,
                    "line": 1,
                  },
                  "start": Object {
-                   "column": 14,
+                   "column": 16,
                    "line": 1,
                  },
                },
                "range": Array [
-                 14,
+                 16,
                  22,
                ],
-               "type": "TSTypeAnnotation",
-               "typeAnnotation": Object {
-                 "loc": Object {
-                   "end": Object {
-                     "column": 22,
-                     "line": 1,
-                   },
-                   "start": Object {
-                     "column": 16,
-                     "line": 1,
-                   },
-                 },
-                 "range": Array [
-                   16,
-                   22,
-                 ],
-                 "type": "TSSymbolKeyword",
-               },
+               "type": "TSSymbolKeyword",
              },
            },
            "loc": Object {
              "end": Object {
                "column": 23,

[JamesHenry]

These kinds of things (the typeAnnotation breaking change) are super tricky in the AST.

You can see a near identical point here: babel/babel#7086

[JamesHenry]

I've pinged Andy and Daniel to get their thoughts on this

[JamesHenry]

I've started a protected ts-2.7 branch as we normally do with changes which relate to not yet stable versions of TS. Please change the base to be that branch

[azz]

Updated to remove prefix: true as per babel/babel#7239 (comment)

[JamesHenry]

Thanks for your patience on this, @azz. I'm having a very difficult 2018 so far, my Grandad died and I've been forced to leave my home due to flooding. Started to get back on track this week, so digging into all these things now.

This one is currently failing the build, but I really want to get a 2.7 compatible release out, so just going to merge and fix up any issues myself.

[azz]

Really sorry to hear that 😔. Hope the rest of the year is better to you.