Unable to generate sourcemap into a separate file

[marvinhagemeister]

I'm unable to generate sourcemap files which are not inline. Setting the sourceMapFile key inside the config (according to the wiki) leads to an error:

// rollup.config.js
export default {
    entry: 'src/main.js',
    format: 'iife',
    moduleName: 'RollupTest',
    dest: 'dist/bundle.js',
    sourceMap: true,
    sourceMapFile: 'dist/bundle.js.map',
    ...
}

Unexpected key 'sourceMapFile' found, expected one of: acorn, banner, cache, dest, entry, exports, external, footer, format, globals, indent, intro, moduleId, moduleName, noConflict, onwarn, outro, plugins, preferConst, sourceMap, targets, treeshake, useStrict

// src/main.js
var foo = 42;

function main() {
    console.log(foo);
    return foo;
}

function woa() {
    return 5;
}

export default main;

Without sourceMapFile I'm able to bundle the above file with the folllowing output:

var RollupTest = (function () {
    'use strict';

    var foo = 42;

    function main() {
        console.log(foo);
        return foo;
    }

    return main;

}());
//# sourceMappingURL=bundle.js.map

But the bundle.js.map itself is missing. No sourcemaps are rendered.

The command rollup -m inline writes the sourcemap correctly into bundle.js

[Rich-Harris]

This is fixed in 0.31.2 – thanks