[vue] process hangs due to babel parser error

[lkho]

Prettier 2.5.1
Playground1

Input 1:

<template>
  <div>
    <div v-for=" a in ">aaaaa</div>
  </div>
</template>

Output 1:

SyntaxError: Unexpected token (1:1)
> 1 |
    | ^

Playground2

Input 2:

<template>
  <div>
    <div v-for=" a in">aaaaa</div>
  </div>
</template>

Output 2:

TypeError: Cannot destructure property 'left' of '(intermediate value)(...)' as it is undefined.
    at printVueFor (https://prettier.io/lib/standalone.js:40:13897)
    at mz (https://prettier.io/lib/standalone.js:40:16762)
    at Object.yz [as embed] (https://prettier.io/lib/standalone.js:40:19230)
    at Object.printSubtree (https://prettier.io/lib/standalone.js:1:220684)
    at yD (https://prettier.io/lib/standalone.js:1:222198)
    at a (https://prettier.io/lib/standalone.js:1:221787)
    at s (https://prettier.io/lib/standalone.js:1:221610)
    at https://prettier.io/lib/standalone.js:40:9647
    at https://prettier.io/lib/standalone.js:1:219866
    at iD.each (https://prettier.io/lib/standalone.js:1:219698)

Expected behavior:

Output 2 should be the expected behavior of both Input 1 and Input 2 since both inputs is a vue syntax error missing the RHS of a v-for

The current problem is, while the playground here successfully return Output 1 as an error, however, Output 1 is thrown at the babel-parser level. When you try to run this Input 1 yourself in your own CLI, with the default highlighting turned on, the parser error will bubbles to the top and go through the highlighting process by codeFrameColumns (from @babel/code-frame), with an empty text = "" value.

prettier/src/main/parser.js

Line 103 in 514046b

error.codeFrame = codeFrameColumns(text, loc, { highlightCode: true });

When you step into the implementation, the code loops infinitely inside the tokenize* generator function.

TL;DR

So the current behavior is, when you run Input 1 in a CLI terminal (i.e. save the code in a file e.g. abc.vue and run $ prettier abc.vue) with highlighting turned on, the process hangs, and CPU is at 100%.

[lkho]

@babel fix: babel/babel#14165