Previously, when lock file contained invalid JSON nix reported a parser
error without specifying the file it came from.
This change adds flake.lock file path to the error message to avoid
confusion.
For example, instead of doing
#include "nix/store-config.hh"
#include "nix/derived-path.hh"
Now do
#include "nix/store/config.hh"
#include "nix/store/derived-path.hh"
This was originally planned in the issue, and also recent requested by
Eelco.
Most of the change is purely mechanical. There is just one small
additional issue. See how, in the example above, we took this
opportunity to also turn `<comp>-config.hh` into `<comp>/config.hh`.
Well, there was already a `nix/util/config.{cc,hh}`. Even though there
is not a public configuration header for libutil (which also would be
called `nix/util/config.{cc,hh}`) that's still confusing, To avoid any
such confusion, we renamed that to `nix/util/configuration.{cc,hh}`.
Finally, note that the libflake headers already did this, so we didn't
need to do anything to them. We wouldn't want to mistakenly get
`nix/flake/flake/flake.hh`!
Progress on #7876
The short answer for why we need to do this is so we can consistently do
`#include "nix/..."`. Without this change, there are ways to still make
that work, but they are hacky, and they have downsides such as making it
harder to make sure headers from the wrong Nix library (e..g.
`libnixexpr` headers in `libnixutil`) aren't being used.
The C API alraedy used `nix_api_*`, so its headers are *not* put in
subdirectories accordingly.
Progress on #7876
We resisted doing this for a while because it would be annoying to not
have the header source file pairs close by / easy to change file
path/name from one to the other. But I am ameliorating that with
symlinks in the next commit.
This allows writing lock files with dirty inputs, so long as they have
a NAR hash. (Currently they always have a NAR hash, but with lazy
trees that may not always be the case.)
Generally dirty locks are bad for reproducibility (we can detect if
the dirty input has changed, but we have no way to fetch it except
substitution). Hence we don't allow them by default.
Fixes#11181.
The ability to substitute inputs was removed in #10612 because it was
broken: with user-specified inputs containing a `narHash` attribute,
substitution resulted in an input that lacked the attributes returned
by the real fetcher (such as `lastModified`).
To fix this, we introduce a new input attribute `final`. If `final =
true`, fetching the input cannot add or change any attributes.
We only attempt to substitute inputs that have `final = true`. This is
implied by lock file entries; we only write a lock file if all its
entries are "final".
The user can specified `final = true` in `fetchTree`, in which case it
is their responsibility to ensure that all attributes returned by the
fetcher are included in the `fetchTree` call. For example,
nix eval --impure --expr 'builtins.fetchTree { type = "github"; owner = "NixOS"; repo = "patchelf"; final = true; narHash = "sha256-FSoxTcRZMGHNJh8dNtKOkcUtjhmhU6yQXcZZfUPLhQM="; }'
succeeds in a store path with the specified NAR hash exists or is
substitutable, but fails with
error: fetching final input '{"final":true,"narHash":"sha256-FSoxTcRZMGHNJh8dNtKOkcUtjhmhU6yQXcZZfUPLhQM=","owner":"NixOS","repo":"patchelf","type":"github"}' resulted in different input '{"final":true,"lastModified":1718457448,"narHash":"sha256-FSoxTcRZMGHNJh8dNtKOkcUtjhmhU6yQXcZZfUPLhQM=","owner":"NixOS","repo":"patchelf","rev":"a0f54334df36770b335c051e540ba40afcbf8378","type":"github"}'
Known behavior changes:
- `MemorySourceAccessor`'s comparison operators no longer forget to
compare the `SourceAccessor` base class.
Progress on #10832
What remains for that issue is hopefully much easier!
Progress on #5638
There are still a global fetcher and eval settings, but they are pushed
down into `libnixcmd`, which is a lot less bad a place for this sort of
thing.
Continuing process pioneered in
52bfccf8d8.
