Confusing error when missing initializer in const declaration

[rhalff]

• Version: v5.11.0
• Platform: Ubuntu x86_64

Whenever a constant is left uninitialized (and no semicolons are used) the resulting error is confusing.

Currently it will report anything specified after it as an error.

I would have expected the same error message as the browser / d8 throws.

Test Script:

$ cat test.js 
'use strict'

function test () {
  const uninitialized
  console.log('test')
}

Node v5.11.0:

$ node test.js 
/srv/psichi/git/nodule/template/test.js:5
  console.log('test')
  ^^^^^^^

SyntaxError: Unexpected identifier
    at exports.runInThisContext (vm.js:53:16)
    at Module._compile (module.js:387:25)
    at Object.Module._extensions..js (module.js:422:10)
    at Module.load (module.js:357:32)
    at Function.Module._load (module.js:314:12)
    at Function.Module.runMain (module.js:447:10)
    at startup (node.js:148:18)
    at node.js:405:3

d8 & browser:
Using d8 (v5.1.0) or the chromium browser (v49.0.2623.87) the error message is much more concise

$ d8 test.js 
test.js:4: SyntaxError: Missing initializer in const declaration
  const uninitialized
        ^^^^^^^^^^^^^
SyntaxError: Missing initializer in const declaration

Babel:
Babel throws the same kind of error, but at least provides some more context:

$ babel-node test.js
/home/rhalff/.nvm/versions/node/v5.11.0/lib/node_modules/babel-cli/node_modules/babel-core/lib/transformation/file/index.js:556
      throw err;
      ^

SyntaxError: /srv/psichi/git/nodule/template/test.js: Unexpected token (5:2)
  3 | function test () {
  4 |   const uninitialized
> 5 |   console.log('test')
    |   ^
  6 | }
  7 | 

[ChALkeR]

I don't see how this is confusing.
Until the next line, there is no error there.

It could have been

const uninitialized
                    = 10;

So, the unexpected token is on the line after const.

If you put semicolons after the lines, it would tell you that a semicolon is unexpected:

  const uninitialized;
                     ^

SyntaxError: Unexpected token ;

Nevertheless, the new behaviour (as seen in v8 5.1.0) is more clear, of course.

[ChALkeR]

This is done inside v8.

In Node.js 6.0 rc4, with v8 5.0, the error message is in line with what you have on d8 5.1:

  const uninitialized
        ^^^^^^^^^^^^^
SyntaxError: Missing initializer in const declaration

[rhalff]

Ok, thanks for the feedback.