Add options `overrides.${name}` and `overrideAll` to all language modules that manage a dependency tree.
This is done in a backward compatible fashion. Old options for overriding dependencies continue working, though those are not displayed in the manual anymore.
For the following modules the manual now suggest using the new unified override options:
- for pip: use `pip.overrides` and `pip.overrideAll` instead of `pip.drvs`
- for nodejs-granular-v3: use `nodejs-granular-v3.overrides` and `nodejs-granular-v3.overrideAll` instead of `nodejs-granular-v3.deps`
- `php-granular`: use `php-granular.override` and `php-granular.overrideAll` instead of `php-granular.deps`
- don't import eval-cache and flags modules by default (those have never been used so far)
- mark options of package-func as internal. Those are for maintainers only and don't need to be rendered by default
- name example more consistently, eg. `{language}-packaging-{feature}` or `{language}-local-development-{feature}`
- move some examples to the modules integration tests directory instead as their purpose was mainly testing and they weren't good example
- module owned checks: import via flake if available
The goal is to reduce the flake inputs visible to the user
Still, the top-level flake re-exposes the outputs of the dev-flake, but
without exposing its inputs. This means a devShell is still available in
the top-level, for example.
This also removes the /modules/flake.nix. Its original purpose was
separating the modules inputs from the development inputs, but this is
now done the opposite way around by moving the dev inputs to
/dev-flake/flake.nix.
The pip locker [sometimes created a URL without hash][1] to reflect that there was a local source.
This produced the following error when trying to evaluate that derivation:
… from call site
at /nix/store/qdzdi6qvrqxfqxhi3j70d5dsl9f5jpby-source/modules/dream2nix/pip/default.nix:86:28:
85| mkDerivation = {
86| src = l.mkDefault (fetchers.${metadata.sources.${config.name}.type} metadata.sources.${config.name});
| ^
87| doCheck = l.mkDefault false;
… while calling 'url'
at /nix/store/qdzdi6qvrqxfqxhi3j70d5dsl9f5jpby-source/modules/dream2nix/pip/default.nix:57:11:
56| fetchers = {
57| url = info: l.fetchurl {inherit (info) url sha256;};
| ^
58| git = info: config.deps.fetchgit {inherit (info) url sha256 rev;};
error: value is null while a string was expected
Of course, one cannot call `builtins.fetchurl` without a `sha256` argument.
Now, local dependencies are specified exactly like that in the lock file. Now, we'll fetch nothing when dealing with local dependencies.
Also, their evaluation when generating `preFixup` attribute is delayed until build time. This was a bigger problem due to the previous bug, but in any case it should still help to reduce evaluation overhead.
FWIW, sometimes local sources might not really exit in the derivation source tree until build time. For example, when building aggregated sources with meta-repo management tools such as Mr. Chef.
[1]: 40b65e4598/pkgs/fetchPipMetadata/src/fetch_pip_metadata/lock_file_from_report.py (L72C28-L72C28)
