async await not deploying in Google Cloud Functions - google-cloud-functions

Question

firebase deploy is giving me this error message:
async function asyncFunction() {
^^^^^^^^
SyntaxError: Unexpected token function
Here's my code:
async function asyncFunction() {
await getText2Speech(word, 'mp3', 'es-ES_EnriqueVoice')
}
asyncFunction();
getText2Speech is a 75-line function that runs perfectly when I call it without async or await.
I have the Node.js 8 runtime in my functions/package.json:
"engines": {
"node": "8"
},
I have Node up to date on my computer:
node -v
v11.2.0
It seems odd that the unexpected token is function, not async. It seems that firebase deploy recognizes async but I have the syntax wrong? es-lint can't find anything wrong with my code.
Could the problem be this:
npm list --depth 0 -g
├── UNMET PEER DEPENDENCY firebase-admin#6.2.0
npm ERR! peer dep missing: firebase-admin#~6.0.0, required by firebase-functions#2.1.0
If I roll back to firebase-admin#~6.0.0 will async await work?

Answer 1

The problem was that something was pointing to eslint v4.5.0, which doesn't support ES2017. I had eslint v5.9.0 installed but eslint -v always returned v4.5.0. I used find . -name 'eslint' to remove every copy of eslint, there were lots of versions, all other my computer. npm uninstall -g eslint doesn't get every copy of eslint. When eslint -v returned nothing then firebase deploy worked.

Answer 2

async/await was deploying on my other computer, then today it stopped deploying. I checked the package.json in the functions folder on both computers, and both were missing
"engines": {
"node": "8"
},
Adding this line, both computers now deploy async/await. I don't know how this object dropped out of the package.json file, and I don't know if this fix will continue to work, but I'll cross my fingers!