lix/src/libexpr/primops
Maximilian Bosch f742438465
Merge legacy fetchGit-builtin with the generic fetchTree-function
The original idea was to implement a git-fetcher in Nix's core that
supports content hashes[1]. In #3549[2] it has been suggested to
actually use `fetchTree` for this since it's a fairly generic wrapper
over the new fetcher-API[3] and already supports content-hashes.

This patch implements a new git-fetcher based on `fetchTree` by
incorporating the following changes:

* Removed the original `fetchGit`-implementation and replaced it with an
  alias on the `fetchTree` implementation.

* Ensured that the `git`-fetcher from `libfetchers` always computes a
  content-hash and returns an "empty" revision on dirty trees (the
  latter one is needed to retain backwards-compatibility).

* The hash-mismatch error in the fetcher-API exits with code 102 as it
  usually happens whenever a hash-mismatch is detected by Nix.

* Removed the `flakes`-feature-flag: I didn't see a reason why this API
  is so tightly coupled to the flakes-API and at least `fetchGit` should
  remain usable without any feature-flags.

* It's only possible to specify a `narHash` for a `git`-tree if either a
  `ref` or a `rev` is given[4].

* It's now possible to specify an URL without a protocol. If it's missing,
  `file://` is automatically added as it was the case in the original
  `fetchGit`-implementation.

[1] https://github.com/NixOS/nix/pull/3216
[2] https://github.com/NixOS/nix/pull/3549#issuecomment-625194383
[3] https://github.com/NixOS/nix/pull/3459
[4] https://github.com/NixOS/nix/pull/3216#issuecomment-553956703
2020-07-28 00:44:39 +02:00
..
context.cc use plain errPos instead of nixCode; fix tests 2020-06-23 15:30:13 -06:00
fetchMercurial.cc Merge remote-tracking branch 'origin/master' into flakes 2020-07-06 16:40:10 +02:00
fetchTree.cc Merge legacy fetchGit-builtin with the generic fetchTree-function 2020-07-28 00:44:39 +02:00
fromTOML.cc use plain errPos instead of nixCode; fix tests 2020-06-23 15:30:13 -06:00