@dwijnand there's supposed to be a NOTICE file too, right?

e.g. https://github.com/scala/scala/blob/2.13.x/NOTICE

Correct, http://www.apache.org/dev/apply-license.html#new:

a correct NOTICE file MUST be included in the same directory as the LICENSE file

I'd recommend:

Dotty
Copyright EPFL and Lightbend, Inc.
License: http://www.apache.org/licenses/LICENSE-2.0

Here is an updated header, following scala/scala's example:

/*
 * Dotty (https://dotty.epfl.ch)
 *
 * Copyright EPFL and Lightbend, Inc.
 *
 * Licensed under Apache License 2.0
 * (http://www.apache.org/licenses/LICENSE-2.0).
 *
 * See the NOTICE file distributed with this work for
 * additional information regarding copyright ownership.
 */

I'd recommend:

Dotty
Copyright EPFL and Lightbend, Inc.
License: http://www.apache.org/licenses/LICENSE-2.0

For the NOTICE file, don't we have to:

• explicitly mention that parts of sources come from scala/scala?
• mention vscode-dotty and and the javascript libraries living under doc-tool/resources/js/ ?

For the NOTICE file, don't we have to: [...]

Yes, I think so. So far we've used https://github.com/lampepfl/dotty/blob/master/AUTHORS.md for this.

The license field in https://github.com/lampepfl/dotty/blob/master/vscode-dotty/package.json will also need to be updated.

Can we avoid adding the header to every file?

Unclear, but at this point scala/scala has already added the header everywhere so to be consistent we need to do the same anyway.

Each original source document (code and documentation, but excluding the LICENSE and NOTICE files) SHOULD include a short license header at the top. If the distribution contains documents not covered by CLA, CCLA or Software Grant (such as third-party libraries) then see the policy guide.

SHOULD

So I guess we could also we just write "Unless stated otherwise, every .scala file in this repository is distributed under the Apache License 2.0." or something. I find it crazy that we can use all these elaborate programming abstractions but we have to copy paste a bunch a boilerplate everywhere for licencing...

That plugin is in fact used in this PR :).

Sorry. Then I didn't understand @OlivierBlanvillain's comment.

I'm not concerned about maintenance, what bothers me is having 10 useless lines at the beginning of every single file. Maybe I need an ad blocker in my text editor or something 😋

IANAL etc, but I think it would be equally valid (and much shorter) for the header to be

// Copyright 2012-2019 EPFL
// Copyright 2012-2019 Lightbend, Inc.
// Licence: Apache-2.0

but I think it would be equally valid (and much shorter) for the header to be

previous round of bikeshedding on this at
scala/scala#7306 (comment)

We have to agree on something if we don't want this PR to rot forever. Do we want to merge the current state or reduce the size of the header first?

We should do exactly what Scala 2 does so keep the current header, anything else will make code sharing harder for no good reason.

May I suggest that it's time to revive or replace this PR? The core of it — replacing BSD license with Apache license — seems crucially important to me.

Feel free to open a new updated pr.

more minimal PR that doesn't do anything with the headers: #8026