plugins: Optional Chaining Causes Build to Fail

• Rollup Plugin Name: @rollup/plugin-typescript
• Rollup Plugin Version: ^3.0.0
• Rollup Version: ^1.31.0
• Operating System (or Browser): Mac OS
• Node Version: v12.3.1

How Do We Reproduce?

git clone git@github.com:bennypowers/rollup-plugin-typescript-optional-chaining-repro.git
cd rollup-plugin-typescript-optional-chaining-repro
npm i
npx rollup -c

Expected Behavior

Compiles

Actual Behavior

Fails with

index.ts → stdout...
[!] Error: Unexpected token (Note that you need plugins to import files that are not JavaScript)
index.ts (2:3)
1: const a = { b: { c: undefined } };
2: a?.b?.c;
      ^
Error: Unexpected token (Note that you need plugins to import files that are not JavaScript)
    at error (/Users/bennyp/Documents/rt-repro/node_modules/rollup/dist/shared/node-entry.js:5400:30)
    at Module.error (/Users/bennyp/Documents/rt-repro/node_modules/rollup/dist/shared/node-entry.js:9820:16)
    at tryParse (/Users/bennyp/Documents/rt-repro/node_modules/rollup/dist/shared/node-entry.js:9713:23)
    at Module.setSource (/Users/bennyp/Documents/rt-repro/node_modules/rollup/dist/shared/node-entry.js:10076:33)
    at /Users/bennyp/Documents/rt-repro/node_modules/rollup/dist/shared/node-entry.js:12362:20
    at async Promise.all (index 0)
    at async Promise.all (index 0)
    at async Promise.all (index 0)

I now present the relevant contents of said repro repo

package.json

{
  "devDependencies": {
    "@rollup/plugin-typescript": "^3.0.0",
    "rollup": "^1.31.0",
    "typescript": "^3.7.5"
  }
}

rollup.config.js

import typescript from '@rollup/plugin-typescript';

export default {
  input: 'index.ts',
  output: {
    format: 'es',
    outDir: '.'
  },
  plugins: [typescript({ typescript: require('typescript') })]
}

index.ts

const a = { b: { c: undefined } };
a?.b?.c;

tsconfig.json

{
  "include": ["index.ts"],
  "compilerOptions": {
    "experimentalDecorators": true,
    "target": "esnext",
    "module": "esnext"
  }
}