Empty output from tsc and out compiler option acting surprisingly

[NickHeiner]

I would not be at all surprised if I was doing something wrong here or if this problem was due to a lack of my understanding, but I think that tsc should have an error message or something here instead of producing surprising results and exiting with code 0.

tsconfig.json

{
  "compilerOptions": {
    "module": "commonjs",
    "out": "out.js",
    "noImplicitAny": true,
    "preserveConstEnums": true,
    "noEmitOnError": true
  },
  "files": [
    "index.ts"
  ]
}

index.ts

import log = require('./log');

export = log('hello world');

log.ts

export = function log(message: string): void {
    console.log('[log]', message);
}

λ tsc -v
message TS6029: Version 1.5.3
nick.heiner@nheiner.local:/tmp/ts  λ tsc -p .
nick.heiner@nheiner.local:/tmp/ts  λ echo $?
0

Expected: As noted in the tsconfig.json docs, all my ts files are concatted into a single out.ts file, respecting what I set in tsconfig.json.

Concatenate and emit output to single file. The order of concatenation is determined by the list of files passed to the compiler on the command line along with triple-slash references and imports. See output file order documentation for more details.

Actual: I see index.js and log.js files created, which look correct, but out.js is empty.

[danquirk]

See #1544