'const enum' in single statement context crashes compiler

[ajafff]

TypeScript Version: 3.0.0-dev.20180712

Search Terms:

Code

if (Boolean())
  const enum Foo {}

Expected behavior:

Some compiler error.

Actual behavior:

TypeError: Cannot read property 'kind' of undefined
    at Object.isBlock (/Users/klaus/code/wotan/node_modules/typescript/lib/tsc.js:9915:21)
    at emitEmbeddedStatement (/Users/klaus/code/wotan/node_modules/typescript/lib/tsc.js:65524:20)
    at emitIfStatement (/Users/klaus/code/wotan/node_modules/typescript/lib/tsc.js:64709:13)
    at pipelineEmitWithHint (/Users/klaus/code/wotan/node_modules/typescript/lib/tsc.js:63854:32)
    at emitNodeWithSourceMap (/Users/klaus/code/wotan/node_modules/typescript/lib/tsc.js:62836:21)
    at pipelineEmitWithSourceMap (/Users/klaus/code/wotan/node_modules/typescript/lib/tsc.js:63726:58)
    at emitNodeWithComments (/Users/klaus/code/wotan/node_modules/typescript/lib/tsc.js:62970:17)
    at pipelineEmitWithComments (/Users/klaus/code/wotan/node_modules/typescript/lib/tsc.js:63718:13)
    at emitNodeWithNotification (/Users/klaus/code/wotan/node_modules/typescript/lib/tsc.js:62486:21)
    at pipelineEmitWithNotification (/Users/klaus/code/wotan/node_modules/typescript/lib/tsc.js:63713:47)

Playground Link: https://agentcooper.github.io/typescript-play/#code/JYMwBAFAQg9jA2BTAhgOwgSgwKDHsAxjKgM4AuYiqArgLZgBicYA3gL5A

Related Issues:

#22682 - about declarations in single statement context
#22686 - similar error for interfaces and type aliases