Update Babel

[jonathantneal]

It would be really sweet if we could also upgrade Babel before the next release. We can just give it a day or two; and if no one can solve it then I can roll it back and release 6 anyway.

[jonathantneal]

> postcss-selector-parser@6.0.0 pretest ~/GitHub/postcss/postcss-selector-parser
> eslint src


> postcss-selector-parser@6.0.0 test ~/GitHub/postcss/postcss-selector-parser
> nyc ava src/__tests__/*.js

~/GitHub/postcss/postcss-selector-parser/node_modules/@babel/traverse/lib/path/context.js:60
      throw new Error(`Unexpected return value from visitor method ${fn}`);
      ^

Error: Unexpected return value from visitor method function (path) {
          return fn.call(state, path, state);
        }

[alexander-akait]

Weird, i think we should update ava first (to be honest i prefer jest 😄 )

[jonathantneal]

@evilebottnawi, ava changed how its throw works, and that would require us to update functions used by the tests. I chose not to take that on yet. Other than that, it’s just 2 snapshots that I had to update.

[alexander-akait]

@jonathantneal what do you think about CI error?

[jonathantneal]

@evilebottnawi, I’ve restored the package-lock.json file.

After updating the babel dependencies in package.json, I deleted package-lock.json so that it could be regenerated. However, when the prepare script failed on npm install, it also failed to regenerate package-lock.json. I didn’t catch this. Thank you!