Adds a `repl-overlays` option, which specifies files that can overlay
and modify the top-level bindings in `nix repl`. For example, with the
following contents in `~/.config/nix/repl.nix`:
info: final: prev: let
optionalAttrs = predicate: attrs:
if predicate
then attrs
else {};
in
optionalAttrs (prev ? legacyPackages && prev.legacyPackages ? ${info.currentSystem})
{
pkgs = prev.legacyPackages.${info.currentSystem};
}
We can run `nix repl` and use `pkgs` to refer to `legacyPackages.${currentSystem}`:
$ nix repl --repl-overlays ~/.config/nix/repl.nix nixpkgs
Nix 2.21.0pre20240309_4111bb6
Type :? for help.
Loading installable 'flake:nixpkgs#'...
Added 5 variables.
Loading 'repl-overlays'...
Added 6 variables.
nix-repl> pkgs.bash
«derivation /nix/store/g08b5vkwwh0j8ic9rkmd8mpj878rk62z-bash-5.2p26.drv»
Change-Id: Ic12e0f2f210b2f46e920c33088dfe1083f42391a
- Use a recursive descent parser so that it's easy to extend.
- Add `@args` to enable customizing command-line arguments
- Add `@should-start` to enable `nix repl` tests that error before
entering the REPL
- Make sure to read all stdout output before comparing. This catches
some extra output we were tossing out before!
Change-Id: I5522555df4c313024ab15cd10f9f04e7293bda3a
Without this, the Meson setup won't bail out if nlohmann_json is
missing, leading to subpar DX (and maybe worse, but I'm not entirely
sure).
Change-Id: I5913111060226b540dcf003257c99a08e84da0de
sometimes these fail with timeouts on loaded machines. let's up the
timeouts until we can pull the tests apart to more reasonable sizes
Change-Id: I2dfff2183cc1f3ff5e6107f43748ac046fe00d05
Functional tests can be run with
`meson test -C build --suite installcheck`.
Notably, functional tests must be run *after* running `meson install`
(Lix's derivation runs the installcheck suite in installCheckPhase so it
does this correctly), due to some quirks between Meson and the testing
system.
As far as I can tell the functional tests are meant to be run after
installing anyway, but unfortunately I can't transparently make
`meson test --suite installcheck` depend on the install targets.
The script that runs the functional tests, meson/run-test.py, checks
that `meson install` has happened and fails fast with a (hopefully)
helpful error message if any of the functional tests are run before
installing.
TODO: this change needs reflection in developer documentation
Change-Id: I8dcb5fdfc0b6cb17580973d24ad930abd57018f6
This was achieved by running maintainers/buildtime_report.sh on the
build directory of a meson build, then asking "why the heck is json
eating our build times", and strategically moving the json using bits
out of widely included headers.
It turns out that putting literally any metrics whatsoever into the
build had immediate and predictable results.
Results are 1382.5s frontend time -> 1175.4s frontend time, back end
time approximately invariant.
Related: https://git.lix.systems/lix-project/lix/issues/159
Change-Id: I7edea95c8536203325c8bb4dae5f32d727a21b2d
Unit tests can be run with `meson test -C build --suite check`.
`--suite check` is optional, as right now that's the only test suite,
but when functional tests are added those will be in a separate suite.
Change-Id: I7f22f1cde4b489b3cdb5f9a36a544f0c409fcc1f
An attrPath prefix of "." indicates no need to try default attrPath prefixes. For example `nixpkgs#legacyPackages.x86_64-linux.ERROR` searches through
```
trying flake output attribute 'packages.x86_64-linux.legacyPackages.x86_64-linux.ERROR'
using cached attrset attribute ''
trying flake output attribute 'legacyPackages.x86_64-linux.legacyPackages.x86_64-linux.ERROR'
using cached attrset attribute 'legacyPackages.x86_64-linux'
trying flake output attribute 'legacyPackages.x86_64-linux.ERROR'
using cached attrset attribute 'legacyPackages.x86_64-linux'
```
And there is no way to specify that one does not want the automatic
search behavior. Now one can specify
`nixpkgs#.legacyPackages.x86_64-linux.ERROR` to only refer to the rooted
attribute path without any default injection of attribute search path or
system.
Change-Id: Iac1334e1470137b7ce11dcf845513810230638ec
(cherry picked from commit d4aed18883b361133607296fb6cd789c47427a38)
static env association is from expr to its enclosing scope, but let
exprs set their association to their *inner* scope. this skips one level
of envs and will cause segfaults if the parent is a with expr.
fixes#145
Change-Id: I1d22146110f071ede21b4eed7ed34b5850ef2ef3
not doing this exposes the binding name order to the annoying
interference of parse order on symbol order, which wouldn't be so bad if
it didn't make the tests less reliable and, importantly, dependent on
linker behavior (due to primop initialization being done in static
initializer, and the order of static initializers being defined only
within a single translation unit).
fixes#143
Change-Id: I3cf417893fbcf19e9ad3ff8986deb7cbcf3ca511
we now keep not a table of all positions, but a table of all origins and
their sizes. position indices are now direct pointers into the virtual
concatenation of all parsed contents. this slightly reduces memory usage
and time spent in the parser, at the cost of not being able to report
positions if the total input size exceeds 4GiB. this limit is not unique
to nix though, rustc and clang also limit their input to 4GiB (although
at least clang refuses to process inputs that are larger, we will not).
this new 4GiB limit probably will not cause any problems for quite a
while, all of nixpkgs together is less than 100MiB in size and already
needs over 700MiB of memory and multiple seconds just to parse. 4GiB
worth of input will easily take multiple minutes and over 30GiB of
memory without even evaluating anything. if problems *do* arise we can
probably recover the old table-based system by adding some tracking to
Pos::Origin (or increasing the size of PosIdx outright), but for time
being this looks like more complexity than it's worth.
since we now need to read the entire input again to determine the
line/column of a position we'll make unsafeGetAttrPos slightly lazy:
mostly the set it returns is only used to determine the file of origin
of an attribute, not its exact location. the thunks do not add
measurable runtime overhead.
notably this change is necessary to allow changing the parser since
apparently nothing supports nix's very idiosyncratic line ending choice
of "anything goes", making it very hard to calculate line/column
positions in the parser (while byte offsets are very easy).
(cherry picked from commit 5d9fdab3de0ee17c71369ad05806b9ea06dfceda)
Change-Id: Ie0b2430cb120c09097afa8c0101884d94f4bbf34
this needs a string comparison because there seems to be no other way to
get that information out of bison. usually the location info is going to
be correct (pointing at a bad token), but since EOF isn't a token as
such it'll be wrong in that this case.
this hasn't shown up much so far because a single line ending *is* a
token, so any file formatted in the usual manner (ie, ending in a line
ending) would have its EOF position reported correctly.
(cherry picked from commit 855fd5a1bb781e4f722c1d757ba43e866d370132)
Change-Id: I120c56a962f4286b1ae3b71da7b71ce8ec3e0535
the parser treats a plain \r as a newline, error reports do not. this
can lead to interesting divergences if anything makes use of this
feature, with error reports pointing to wrong locations in the input (or
even outside the input altogether).
(cherry picked from commit 2be6b143289e5479cc4a2667bb84e879116c2447)
Change-Id: Ieb7f7655bac8cb0cf5734c60bd41723388f2973c
previously we reported the error at the beginning of the binding
block (for plain inherits) or the beginning of the attr list (for
inherit-from), effectively hiding where exactly the error happened.
this also carries over to runtime positions of attributes in sets as
reported by unsafeGetAttrPos. we're not worried about this changing
observable eval behavior because it *is* marked unsafe, and the new
behavior is much more useful.
(cherry picked from commit 1edd6fada53553b89847ac3981ac28025857ca02)
Change-Id: I2f50eb9f3dc3977db4eb3e3da96f1cb37ccd5174
we already normalize attr order to lexicographic, doing the same for
formals makes sense. doubly so because the order of formals would
otherwise depend on the context of the expression, which is not quite as
useful as one might expect.
(cherry picked from commit 4147ecfb1c51f3fe3b4adcbd4e753fd487dab645)
Change-Id: I3fd0dbdef3ac7447a3a03ff20bb514a0d0f23fb1
the parser modifies its inputs, which means that sharing them between
the error context reporting system and the parser itself can confuse the
reporting system. usually this led to early truncation of error context
reports which, while not dangerous, can be quite confusing.
(cherry picked from commit d384ecd553aa997270b79ee98d02f7cf7e1849e6)
Change-Id: I677646b5675b12b2faa787943646aa36dc6e6ee3
These now have equivalents in the standard lib in C++20. This change was
performed with a custom clang-tidy check which I will submit later.
Executed like so:
ninja -C build && run-clang-tidy -checks='-*,nix-*' -load=build/libnix-clang-tidy.so -p .. -fix ../tests | tee -a clang-tidy-result
Change-Id: I62679e315ff9e7ce72a40b91b79c3e9fc01b27e9
This builtin is only going to cause us problems because we are not Nix,
so let's just falsify being in the 2.18 series, since that is the
closest target that has any meaning.
In future we might want to have a better feature detection mechanism,
for when we actually add stuff to some builtin's attr set argument. But
builtins.nixVersion is just going to be hopelessly broken and it should
be stubbed out.
Fixes https://git.lix.systems/lix-project/lix/issues/144
Change-Id: Id7390b32a29c6147f2977737d81846320de5d67e
diagnose attr duplication at the path the duplication was detected, not
at the path the current attribute wanted to place. doing the latter is
only correct if a leaf attribute was duplicated, not if an attrpath was
set to a non-attrset in one binding and a (potentially implied) attrset
in another binding.
fixes#124
Change-Id: Ic4aa9cc12a9874d4e7897c6f64408f10aa36fc82
It happens with some frequency that plugins that might be unimportant to
the evaluation at hand mismatch with the nix version, leading to
spurious load failures. Let's make these non fatal.
Change-Id: Iba10e951d171725ccf1a121bcd9be1e1d6ad69eb
This is because they are unrepresentable in the source files with
commentary but not in the output, so we should just eat them in
normalization. It's ok.
Change-Id: I2cb7e8b3fc7b00874885bb287cbaa200b41cb16b
This allows for automating using the repl without needing a PTY, with
very easy to write test files.
Change-Id: Ia8d7854edd91f93477638942cb6fc261354e6035
This parser can be reused for other purposes. It's inspired by
https://bitheap.org/cram/
Although eelco's impostor exists https://github.com/mobusoperandi/eelco,
it is not very nice to depend on out of tree testing frameworks with no
way to customize them.
Change-Id: Ifca50177e09730182baf0ebf829c3505bbb0274a
using the total-attrs-printed and total-list-items-printed counters to
calculate how many attrs were elided only works properly if no nesting
is involved. once things do nest the global counter can exceed the size
of the currently printed object, leading to unsigned wrapping and great
overestimation of elided counts. counting locally in addition to global
counts fixes this.
these are functional tests because creating these objects requires the
evaluator to not be a huge amount of code, and we also want defaults to
be tested for cli usage.
fixes#14
Change-Id: Icb9a0cb21b2f4bacbc5e9dcdd8c0b9055b4088a7
this lets us set per-test-program environment variables rather than only
a single, global default. this was supported in nix originally but
might've gone partially missing in the upstream backports process?
Change-Id: Iad0919841b1b6d11e0b7ebd3920449a62f544e77
This has some Flaws for sure (like, it is going to be a bit stretched to
use for repl characterization), but it is a start.
Change-Id: I258c8beb3aee236f45818a03be83bcda858120c9
desugaring inherit-from to syntactic duplication of the source expr also
duplicates side effects of the source expr (such as trace calls) and
expensive computations (such as derivationStrict).
(cherry picked from commit cefd0302b55b3360dbca59cfcb4bf6a750d6cdcf)
Change-Id: Iff519f991adef2e51683ba2c552d37a3df7a179e
for plain inherits this is really just a stylistic choice, but for
inherit-from it actually fixes an exponential size increase problem
during expr printing (as may happen during assertion failure reporting,
on during duplicate attr detection in the parser)
(cherry picked from commit ecf8b12d60ad2929f9998666cf0966475b91e291)
Change-Id: Ie55f0cb01a37e766414c31f8d40f51c2c7d106b0
this also has the effect of sorting let bindings lexicographically
rather than by symbol creation order as was previously done, giving a
better canonicalization in the process.
(cherry picked from commit 6c08fba533ef31cad2bdc03ba72ecf58dc8ee5a0)
Change-Id: Ia887f629305645bb8a165fbbc0d32e620912595a
without these changes the tests will very repeatably (although not very
reliably) wedge in our runs. the ssh command starts, opens a sessions,
does something, the session closes again, but the test does not move on.
adding *just* the redirect and not the unit waits is not sufficient
either, it needs both. this feels like a bug in the nixos testing
framework somewhere, but digging that far is not in the cards right now.
Change-Id: Idab577b83a36cc4899bb5ffbb3d9adc04e83e51c
