Refactor the `force!` macro to a method on `Value` which returns a
smart-pointer-esque type, which simplifies the callsite and eliminates
rightward drift, especially for high-arity builtins.
Change-Id: I97a7837580accfb4bbd03b24f2acdbd38645efa5
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6656
Autosubmit: grfn <grfn@gws.fyi>
Reviewed-by: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Thunks might be encountered deep in equality comparison (eg nested
inside a list or attr-set), at which point we need to force them in
order to compare them for equality (or else we panic when trying to get
at their value).
Fixes: b/192
Change-Id: I912151085f8298f30d5214c7965251c9266443f2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6652
Autosubmit: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
Pass in, but ignore, a mutable reference to the VM to the `nix_eq`
functions, in preparation for using that VM to force thunks during
comparison.
Change-Id: I565435d8dfb33768f930fdb5a6b0fb1365d7e161
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6651
Autosubmit: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
Using rust's PartialEq trait to implement Nix equality semantics is
reasonably fraught with peril, both because the actual laws are
different than what nix expects, and (more importantly) because certain
things actually require extra context to compare for equality (for
example, thunks need to be forced). This converts the manual PartialEq
impl for Value (and all its descendants) to a *derived* PartialEq
impl (which requires a lot of extra PartialEq derives on miscellanious
other types within the codebase), and converts the previous
nix-semantics equality comparison into a new `nix_eq` method. This
returns an EvalResult, even though it can't currently return an error,
to allow it to fail when eg forcing thunks (which it will do soon).
Since the PartialEq impls for Value and NixAttrs are now quite boring,
this converts the generated proptests for those into handwritten ones
that cover `nix_eq` instead
Change-Id: If3da7171f88c22eda5b7a60030d8b00c3b76f672
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6650
Autosubmit: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
As before, this limits the cases to a relatively small number because
otherwise things get quite large.
Change-Id: I5371dc56418fca52e1dd1d905b20868f647091ba
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6649
Autosubmit: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
Only running 20 cases for now, since Value can get quite big if you let
it run for a while.
Change-Id: I09ef19da22c789c4869793836c98937c44595340
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6648
Autosubmit: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
this was found by proptests!
Change-Id: I16d6a6ece3b20cdddd6f78c94cc87befb1b651e6
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6647
Autosubmit: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
Impl Arbitrary for Value (and NixAttrs and NixList) in the same way we
did for NixString. Value currently only generates non-"internal"
values (no thunks, AttrNotFound, etc.) and can't generate
functions (builtins or closures), because those'd require full
generation of tvix bytecode, which is a bit more work than I'd like to
do now - there's a `todo!` left in the code for a place where we could
allow opting-in to internal values and functions later.
Change-Id: I07a59e2b1d89cfaa912d4ecebd642caf4ddb040a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6627
Autosubmit: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
Add a suite of proptests covering the laws of the handwritten stdlib
trait impls (Eq, Ord, and Hash) for String, generated from a new set of
macros for generating those tests which can be applied to other types.
Change-Id: Ib3276c9e96fca497aece094e5612707d3dc77ccd
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6626
Autosubmit: grfn <grfn@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
The From<String> impl for NixString only generates StringRepr::Heap
strings, but we want to make sure we're testing StringRepr::Smol too
Change-Id: I6d04b9cf12ef8462fe2788e0c6414b165f40311d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6629
Autosubmit: grfn <grfn@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This function is necessary for all builtins that expect some form of
path as an argument. It is merely a wrapper around coerce_to_string that
can shortcut if we already have a path. The absolute path check is done
in the same way as in C++ Nix for compatibility, although it should
probably be revised in the long term (think about Windows, for example).
Since coercing to a path is not an operation possible in the language
directly, this function can live in the builtins module as the only
place it is required.
Change-Id: I69ed5455c00d193fea88b8fa83e28907a761cab5
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6574
Autosubmit: sterni <sternenseemann@systemli.org>
Reviewed-by: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Define `.len()` method on `NixAttrs` to preallocate the capacity of the result
vector.
Also anchor an errant comment to its context (I think).
Change-Id: I268f15025d453d7b3ae1146558c80e51433dd2a8
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6546
Reviewed-by: wpcarro <wpcarro@gmail.com>
Reviewed-by: sterni <sternenseemann@systemli.org>
Autosubmit: wpcarro <wpcarro@gmail.com>
Tested-by: BuildkiteCI
Implement C++ Nix's `EvalState::coerceToString` minus some of the Path
/ store handling. This is currently only used for `toString` which does
all possible coercions, but we've already prepared the weaker coercion
variant which is e.g. used for builtins that expect string arguments.
`EvalState::coerceToPath` is still missing for builtins that need a
path, but it'll be easy to build on top of this.
Change-Id: I78d15576b18921791d04b6b1e964b951fdef22c6
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6571
Autosubmit: sterni <sternenseemann@systemli.org>
Reviewed-by: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Pointed out by sterni in cl/6370
Change-Id: I324d8049a2702ced8f30ad43a64d63ae79dd0eab
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6569
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This very closely follows the way it's done for warnings, but errors
have a lot more information available in some cases which we do not
surface yet.
Note also that due to requiring the `CodeMap`, this is not yet called
from eval.rs as the way that is threaded through needs to be
refactored, so only the method for reporting these errors as strings
is implemented so far.
Next steps for this will be to add a generic diagnostics module that
reduces some of the boilerplate for this between warnings & errors,
and which will also give us a good point in the future to switch to a
fancier diagnostics crate.
Change-Id: If6bb209f8e7a568d866e516a90335b9b2afbf66d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6534
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
This struct will be responsible for tracking upvalues (and is a
convenient place to introduce optimisations for reducing value clones)
instead of a plain value vector.
The main motivation for this is that the upvalues will have to capture
the `with`-stack fully and I want to avoid duplicating the logic for
this between the two capturing types.
Change-Id: I6654f8739fc2e04ca046e6667d4a015f51724e99
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6485
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
As pointed out by sterni in cl/6205, this is actually possible in
syntactically valid expressions like
{ ${12 + 13} = 12; }
Change-Id: Id8a1e3aceb551f288f9050c4eea563eb6572f1a7
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6461
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
As pointed out by grfn on cl/6091
Change-Id: I28308577b7cf99dffb4a4fd3cc8783eb9ab4d0d6
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6460
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
At the point where control flow exits Thunk::force (which may be due
to recursing), it is vital that there is no longer a borrow to the
inner thunk representation, otherwise this can cause accidental
infinite recursion (which will be detected, but cause failures on
valid code).
Change-Id: I2846f3142830ae3110a4f5d2299e9d7928634504
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6436
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This could occur when the disassembler is enabled and tracing the
runtime while a thunk is being evaluated, as it would not be possible
for the *tracer* to borrow the thunk at this exact moment.
However, we know that if the borrowing fails here we are dealing with
a not-fully evaluated thunk (blackhole), which should just print the
internal representation.
Change-Id: I4bdb4f17818d55795368e3d28842048f488f0a91
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6416
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
Previously, "calling" (setting up the VM run loop for executing a call
frame) and "running" (running this loop to completion) were separate
operations.
This was basically an attempt to avoid nesting `VM::run` invocations.
However, doing things this way introduced some tricky bugs for exiting
out of the call frames of thunks vs. builtins & closures.
For now, we unify the two operations and always return the value to
the caller directly. For now this makes calls a little less effective,
but it gives us a chance to nail down some other strange behaviours
and then re-optimise this afterwards.
To make sure we tackle this again further down I've added it to the
list of known possible optimisations.
Change-Id: I96828ab6a628136e0bac1bf03555faa4e6b74ece
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6415
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
The casting methods of `Value` are pretty verbose, and actually
incorrect before this commit as they did not account for inner thunk
values.
To address this, we first attempt to make them correct by introducing
a standard macro to generate them and traverse the inner thunk(s) if
necessary.
This is likely to be a performance hit as it will now involve more
cloning of values. We can do multiple things to alleviate this, but
should do some measurements first.
Change-Id: If315d6e2afe7b69db727df535bc6cbfb89a691aa
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6412
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This makes it possible for builtins to force values on their own,
without the VM having to apply a strictness mask to the arguments
first.
Change-Id: Ib49a94e56ca2a8d515c39647381ab55a727766e3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6411
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
With this, if an error occurs while forcing a thunk (which is very
likely) it is threaded through to the top by wrapping it in the
ErrorKind::ThunkForce variant.
We could use this to generate "stacktrace-like" error output if we
wanted, or simply jump through and discard everything except the
innermost error.
Change-Id: I3c1c8708c2f73ae062815adf490ce935b1979da8
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6409
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
Previously error spans were optional because the information about
code spans was not available at runtime. Now that this information has
been added, the error type will always carry a span.
This change is very invasive all throughout the codebase. This is due
to the fact that many functions that are called *by* the VM expected
to return `EvalResult`, but this no longer works as the span
information is not available to those functions - only to the VM
itself.
To work around this the majority of these functions have been changed
to return `Result<T, ErrorKind>` instead and an accompanying macro in
the VM constructs the "real" error.
Note that this implementatino currently has a bug where errors
occuring within thunks will yield the location at which the thunk was
forced, not the location at which the error occured within the code.
This will be fixed soon, but the commit is large enough as is.
Change-Id: Ib1ecb81a4d09d464a95ea7ea9e589f3bd08d5202
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6408
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
Get the length of a list
Change-Id: I41d91e96d833269541a1b3c23b7cc879f96d1e5a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6407
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Note that I've allowed `needless_lifetimes` for the attribute set
iterator, as I find the type easier to understand with these
annotations present.
Change-Id: I33abb17837ee4813076cdb9a87f54bac4a37044e
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6373
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This does not require a custom iterator type (for now?)
Change-Id: I5beb194bd8629571bd4040c69c977c27149807fa
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6371
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
If a thunk is already evaluated, there are cases where due to the
memoisation implementation something might observe a value wrapped in
a thunk.
In these cases, the implementation of `Display` and `PartialEq` must
delegate to the underlying value.
Note that there are a handful of other cases like these which we need
to cover.
It is a little tricky to write integration tests for these directly,
especially as some of the open-upvalue optimisations coming down the
pipe will reduce the number of observable thunks.
One test that covers a part of this behaviour is currently
disabled (needs some more machinery), but it's being brought back in
the next commits.
Change-Id: Iaa8cd338c12236af844bbc99d8cec2205f0d0095
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6370
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
Implementing iteration over NixAttrs requires a custom iterator type
in order to encapsulate the different representations. The BTreeMap
for example has its own iterator type which needs to be encapsulated.
This is mostly boilerplate code, but for a change some simple unit
tests have been added in.
Change-Id: Ie13b063241d461b810876f95f53878388e918ef2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6367
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
These static strings show up a bunch when dealing with the internals
of attribute sets, and having them available as static references is
required.
Due to the way const expressions are evaluated, taking a reference to
the existing NixString::NAME / NixString::VALUE items does not work
and the references themselves need to be const-evaluated.
Change-Id: If6e75847af978118a3b266fe6a3242321722434d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6366
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
The VM previously took care of repeatedly forcing a thunk until it
reached an evaluated state. This logic is now encapsulated inside of
the `Thunk::force` implementation.
In addition, force no longer returns a reference to the value by
default, leaving it up to callers to decide whether they want to
borrow the value or not (a helper is provided for this).
Change-Id: I2aa7da922058ad1c57fbf8bfc7785aab7971c02b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6365
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
This operation forces the evaluation of a thunk.
There is some potential here for making an implementation that avoids
some copies, but the thunk machinery is tricky to get right so the
first priority is to make sure it is correct by keeping the
implementation simple.
Change-Id: Ib381455b02f42ded717faff63f55afed4c8fb7e3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6352
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
The capacity (i.e. number of builtins) is known from the lambda, so we
can size it correctly right away.
Change-Id: Iab0b5a3f47d450fa9866c091ebbbed935b934907
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6351
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
This trait abstracts over the commonalities of upvalue handling
between closures and thunks.
It allows the VM to simplify the code used for setting up upvalues,
without duplicating between the two different types.
Note that this does not yet refactor the VM code to optimally make use
of this.
Change-Id: If8de5181f26ae1fa00d554f1ae6ea473ee4b6070
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6347
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
For now, do not distinguish between closing and non-closing thunks, it
will make the initial implementation easier. See Knuth etc.
Change-Id: I0bd51e0f89f2c77e90bac63b507e5027b649e3d8
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6346
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Introduces the representation of runtime thunks, that is lazily
evaluated values. Their representation is very similar to closures.
Change-Id: I24d1ab7947c070ae72ca6260a7bbe6198bc8c7c5
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6343
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
This instruction finalises the initialisation of deferred upvalues in
closures (and soon, thunks).
The compiler does not yet emit this instruction, some more accounting
is needed for that.
Change-Id: Ic4181b26e19779e206f51e17388559400da5f93a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6337
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
This will leave a sentinel value in the upvalue slot in which the
actual value is to be captured after resolution once a scope is fully
set up.
Change-Id: I12b37b0dc8d32603b03e675c3bd039468e70b354
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6336
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
The previous closure refactoring introduced a bug in which the same
closure object would get mutated constantly for each instance of a
closure, which is incorrect behaviour.
This commit instead introduces an explicit new Value variant for the
internal "blueprint" that the compiler generates (essentially just the
lambda) and uses this variant to construct the closure at runtime.
If the blueprint ever leaks out to a user somehow that is a critical
bug and tvix-eval will panic.
As a ~treat~ test for this, the fibonacci function is being used as it
is a self-recursive closure (i.e. different instantiations of the same
"blueprint") getting called with different values and it's good to
have it around.
Change-Id: I485de675e9bb0c599ed7d5dc0f001eb34ab4c15f
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6323
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
This puts together the puzzle pieces for threading dynamic
upvalues (that is, upvalues resolved from the `with`-stack) all the
way through.
Reading the test case enclosed in this commit and walking through it
is recommended to understand what problem is being tackled here.
In short, because the compiler can not statically know *which*
with-scope a dynamic argument is resolved from it needs to lay the
groundwork for resolving from *all* possible scopes.
There are multiple different approaches to doing this. The approach
chosen in this commit is that if a dynamic upvalue is detected, the
compiler will emit instructions to close over this dynamic value
in *all* enclosing lambda contexts.
It uses a new instruction for this that will leave around a sentinel
value in case an identifier could not be resolved, and wire the
location of this found value (or sentinel) up through the upvalues to
the next level of nesting.
In this tradeoff, tvix potentially closes over more upvalues than are
needed (but in practice, how often do people create *really* deep
`with`-stacks? and in *this* kind of code situation? maybe we should
even warn for this!) but avoids keeping the entire attribute sets
themselves around.
Looking at the test case, each surrounding closure will close
over *all* dynamic identifiers that are referenced later on visible to
it, but only the last one for each identifier will actually end up
being used.
This also covers our bases for an additional edge-case this creates,
in which an identifier potentially resolves to a dynamic upvalue *and*
to a dynamic value within the function's own scope (again, would
anyone really do this?) by introducing a resolution instruction for
that particular case.
There is likely some potential for cleaning up this code which is
quite ugly in some parts, but as this implementation is now carefully
calibrated to work I decided it is time to commit it and clean it up
in subsequent commits.
Change-Id: Ib701e3e6da39bd2c95938d1384036ff4f9fb3749
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6322
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
This is required to efficiently construct the upvalue array at
runtime, as there are situations where during Closure construction
multiple things already have a reference to the closure (e.g. a
self-reference).
Change-Id: I35263b845fdc695dc873de489f5168d39b370f6a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6312
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
These need to be handled specially by the runtime if the compiler
determines that a given local must be resolved via `with`.
Note that this implementation has a bug: It currently allows `with`
inside of nested lambdas to shadow statically known identifiers. This
will be cleaned up in the next commit.
Change-Id: If196b99cbd1a0f2dbb4a40a0e88cdb09a009c6b9
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6299
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
... same as the others
Change-Id: I9c8868388c10b0b6484c5bdd3799d801296c6979
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6292
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Fully implements the instructions for compiling closure
objects (without runtime handling yet).
Closure (and thunk) objects are created at runtime by capturing all
known upvalues. To represent this, the instructions for creating them
need to have a variable number of arguments. Due to that, this commit
introduces new variants in OpCode that are not actually operations,
but data.
If the VM is implemented correctly, the instruction pointer should
never point at these. Due to this, the VM will panic if it sees a data
operand during an execution run.
Change-Id: Ic56b49b3a42736dc437751e76df0e89c8d0619c6
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6291
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This adds a new upvalue tracking structure in the compiler to resolve
upvalues and track their positions within a function when compiling a
closure.
The compiler will emit runtime upvalue access instructions after this
commit, but the creation of the runtime closure object etc. is not yet
wired up.
Change-Id: Ib0c2c25f686bfd45f797c528753068858e3a770d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6289
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Refactors the update function to take the attribute sets by value
instead.
To facilitate this, we use an equivalent of the currently unstable
`Rc::clone_or_unwrap` in the VM when encountering attribute sets, so
that in cases where the only references to the attrs being updated are
the ones on the stack those clones are avoided completely.
This does make update() a little bit more tricky internally, as some
optimised branches can directly return the moved value, and others
need to destructure with ownership. For this reason there are now two
different match statements handling the different ownership cases.
Change-Id: Ia77d3ba5c86afb75b9f1f51758bda61729ba5aab
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6279
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
This is no longer needed for anything and the extra clone here is not
really more costly than constructing a blackhole value in a different
place.
Change-Id: I5c63085b1b4418b629ea58a42e3bfe9a9b586d76
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6275
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Without this escape, it is possible for Nix to produce escaped
representations which are not literal Nix values again.
This was fixed in upstream Nix in
https://github.com/NixOS/nix/pull/4012 (though only for eval, not in
the REPL) and the updated test is picked from upstream after that commit.
Because we run the C++ Nix tests against our test suite as well, this
also bumps our custom Nix 2.3 to a commit that includes the
cherry-picked fix from the PR above.
Change-Id: I478547ade65f655c606ec46f7143932064192283
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6271
Reviewed-by: grfn <grfn@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This struct will carry the upvalue machinery in addition to the lambda
itself. For now, all lambdas are wrapped in closures (though
technically analysis of the environment can later remove innermost
Closure wrapper, but this optimisation may not be worth it).
Change-Id: If2b68549ec1ea4ab838fdc47a2181c694ac937f2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6269
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
The blackhole allocation is not going to be cheaper than cloning this.
Change-Id: Id3ad44812decb4392830be06645e67bb0a982b96
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6267
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
This avoids copying around the value more than needed.
Change-Id: I35949d16dad7fb8f76e0f641eaccf48322144777
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6263
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
The set of things that can leak out of `builtins` into the global
scope is statically known (it is what Nix 2.3 leaks there,
essentially).
This is a mild change over the previous mechanism, where instead at
the point where the `builtins` set is constructed we "lift" the
globals out of there (if they exist).
This way users will still eventually be able to add additional
builtins, HOWEVER they will not be able to leak them into the global
scope.
Note that upstream Nix technically leaks _all_ builtins into the
global scope using the `__*` prefix, but we are trying to avoid this
in Tvix if it is not required in nixpkgs.
Change-Id: Ie9dec2ce33740134f3b2464eba3749f421dd5953
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6258
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Adds a new builtins module in which builtins can be constructed. The
functions in this module should return a correctly structured value to
be passed to the compiler's `globals`.
This is wired up all the way to the compiler with an example
`toString` builtin, available as a global. Note that this does not yet
actually behave like the real toString, which has some differences
from `Display`.
Change-Id: Ibb5f6fbe6207782fdf2434435567fc1bd80039a5
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6254
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Builtins are represented as a Rust function pointer that accepts a
vector of arguments, which represents variable arity builtins.
Change-Id: Ibab7e662a646caf1172695d876d2f55e187c03dd
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6251
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Changes the internal compiler plumbing to not just return a chunk of
code, but the same chunk wrapped inside of a lambda value.
This is one more step towards compiling runtime lambdas.
Change-Id: If0035f8e65a2970c5ae123fc068a2396e1d8fd72
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6240
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This starts paving the way for nicer, source-code based error
reporting.
Right now the code paths in the VM do not emit annotated errors, as we
do not yet preserve that structure from the compiler. However, error
emitting code paths in the compiler have been amended to include known
nodes.
Change-Id: I1b74410ffd891c40cd913361bd73c4336ec8aa5b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6235
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
These were missing an additional level of escaping, silly oversight
caught by an upstream test.
Change-Id: I0312084475e4b88c83945614e9aa5b34c6bc3ec2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6232
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Not sure how exactly this snuck in, but it caused some subtle
breakages in deeply nested attribute sets.
Change-Id: I8049ce912405d3750031f79cc8d86ff1c3c02c2b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6208
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
We're confident that we're handling all branches that can reasonably
occur from valid AST, any other cases should be considered a critical
evaluator bug and panic rather than surfacing something that looks
like user error.
Change-Id: If96966eb32b8ff12fcaeb9ea3b0c8fc51b6abd11
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6205
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
This is actually *tested* behaviour in C++ Nix, so we need to
implement it here, too.
Change-Id: Ic4a4659a2f04cdd928cbe78a85dae90401515371
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6199
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
grfn pointed out in cl/6082 that this is actually the desugaring of
the write! macro, so it doesn't make sense to write it out.
Change-Id: If7c055b042ad22b034722aec1eaadba92736d684
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6180
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
For representation wrappers that are used to control the visibility of
type internals, this ensures that the wrapper does not increase the
size of the type.
In practice, the optimiser likely does this anyways but it is good to
guarantee it.
Change-Id: Ic6df7d668fe6006dfbd5b6cfcfc2088afa95b810
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6178
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This sentinel value is going to be used for certain nested accesses
into attribute sets.
There is a new instruction similar to `OpAttrsSelect` which leaves the
sentinel on the stack if a key is not found, instead of raising an
error.
Additionally, a new jump instruction makes its jump operation
conditional on finding such a sentinel value.
Change-Id: I2642f0a0bcc85bbe0ead68ea09a7dd794dbedeac
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6166
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
The only uses of the static variant were for `"name"` and `"value"`,
which are both small enough to fit into a SmolStr. The size of
NixString accomodates `String` anyways, so we may as well inline them.
Additionally smol_str is already in the dependency graph because rnix
uses it, and using it for representations of identifiers is sensible.
Change-Id: I9969312256d1657d69128e54c47dc7294a18ce58
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6165
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
Having these visible more explicitly is useful while debugging.
Change-Id: I86b497883063d32792b635eb4514b7aeae484af4
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6164
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
Fairly straightforward, handling the optimised representations
manually and otherwise delegating to BTreeMap.
Note that parsing of raw identifiers is not yet implemented.
Encountering an identifier node usually means that there is locals
access going on, so we need a special case for compiling a node in
such a way that an identifier's literal value ends up on the stack.
Change-Id: I13fbab7ac657b17ef3f4c5859fe737c321890c8a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6158
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
This operation is required because both sides of the logical operators
are strictly evaluated by Nix, even if the resulting value is not used
further.
For example, in our implementation of `&&`, if the left-hand side is
`true`, then the result of the expression is simply the right-hand
side value. This value must be asserted to be a boolean for the
semantics of the language to work correctly.
Change-Id: I34f5364f2a444753fa1d8b0a1a2b2d9cdf7c6700
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6157
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
These expressions use simple jumps to skip the correct expression
conditionally in the bytecode by advancing the instruction pointer.
Note that these expressions are already covered by a test behind the
`nix_tests` feature flag, but adding more is probably sensible.
Change-Id: Ibe0eba95d216321c883d3b6b5816e2ab6fe7eef1
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6148
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>
Wraps the string representation in an additional newtype struct with a
private field in order to hide the representation from other modules.
This is done in order to avoid accidental leakage of the internals
outside of value::string.
In fact, this caught a mistake in the compiler module which was
directly constructing an internal variant.
Change-Id: If4b627d3cff7ab9cd50ca1a3ac73245d4dcf7aef
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6147
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Wraps the attrs representation in an additional newtype struct with a
private field in order to hide the representation from other modules.
This is done in order to avoid accidental leakage of the internals
outside of value::attrs.
Change-Id: I68d1d02514aa0443df4c39801001a3f1f6cc5d5c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6146
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Ensuring that the implementation is not leaking out of the module lets
us keep things open for optimisations (e.g. empty list or pairs
through tuples).
Change-Id: I18fd9b7740f28c55736471e16c6b4095a05dd6d0
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6145
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
The underlying implementation does a few tricks based on which pair of
attrset representations is encountered.
Particularly the effect of short-circuiting the empty cases might be
relevant in nixpkgs/NixOS, due to the use of lib.optionalAttrs.
Change-Id: I22b978b1c69af12926489a71087c6a6219c012f3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6140
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
I assumed that `Ord` is a marker trait like `Eq`, but it actually has
a member. Without this ordering was incoherent.
Change-Id: Id37cbdf333daf748d29b85243046c7e061b1ce29
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6139
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Nix displays a maximum of 5 digits for floating points.
Change-Id: Ifa3c0d96fa0b24e3be8f94dfebc99e602a258355
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6133
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
When printing strings as identifiers (in attribute sets), the string
should only be quoted and escaped if it contains escape characters.
Change-Id: If2bcfa1e93dc8f00be4d7a57ec1d82fc679103c3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6127
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
Nix strings displayed to users must be escaped the same way as they
are in C++ Nix. This adds the scaffolding for escapes, but is most
likely not yet complete.
Change-Id: Icfdcb2ac98d292c567ba894a92b6529a53e0cc17
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6124
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Instead of comparing the enum variants (which does not yield useful
behaviour), compare &str representations of the string instead.
Change-Id: I5e94b5f6c91b4561e1bc7c36d586f3d23c243764
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6112
Tested-by: BuildkiteCI
Reviewed-by: eta <tvl@eta.st>
For cases where the strings are statically known (such as the
oft-occuring name/value), this can be a useful optimisation.
It's also much more convenient in tests.
Change-Id: Ie462b684805bd4986ea5e85ca4bff663bc2d3c3c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6111
Tested-by: BuildkiteCI
Reviewed-by: eta <tvl@eta.st>
These do not yet test nested attribute sets; we need to add some more
inspection primitives first.
Change-Id: Icfc99bf17c73ebefc0d882a84f0ca73ec688a54d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6110
Reviewed-by: eta <tvl@eta.st>
Tested-by: BuildkiteCI
With this change, nested attribute sets can now be created from
literals.
This required some logic for dealing with cases where at a deeper
nesting point a literal attribute set was constructed from an
optimised representation.
For example, this is valid Nix code:
```nix
{
a = {}; # creates optimised empty representation
a.b = 1; # wants to add a `b = 1` to it
b = { name = "foo"; value = "bar"; }; # creates optimised K/V repr
b.foo = 42; # wants to add an additional `foo = 42`
}
```
In these cases, the attribute set must be coerced to a map
representation first which is achieved by the new internal
NixAttr::map_mut helper.
Change-Id: Ia61d3d9d14c4e0f5e207c00f6a2f4daa3265afb2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6109
Reviewed-by: eta <tvl@eta.st>
Tested-by: BuildkiteCI
The internal optimisations of the set representation were previously
leaking into the VM, which is highly undesirable.
Keeping it encapsulated allows us to do additional optimisations
within value::attrs without being concerned about its use in the VM.
Change-Id: I7e7020bb0983b9d355d3db747b049b2faa60131f
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6108
Reviewed-by: eta <tvl@eta.st>
Tested-by: BuildkiteCI
There are some notions of equality (due to e.g. different backing
variants for types, or Nix particularities) that don't work correctly
when deriving PartialEq.
Change-Id: Ide83ae67d051cc0b3ca89cefb283f17d0207acce
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6105
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This is required for constructing nested attribute sets at runtime.
There'll be quite a lot of optimisation potential with this solution
eventually, if it should turn out to be a bottleneck.
This introduces a conceptual change, in that the `Value` enum is now
an enum representing "all runtime values" instead of "all Nix language
types". This makes sense in general, as this type will also contain
Chunk representations etc. which are not exposed to users.
Change-Id: Ic5f72b2a0965b146c6a451efad34c6a81ca1aad8
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6103
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Users may construct a pair that falls into the name/value optimisation
but where `name` is not actually a string, as from the language
perspective there is nothing special about this attribute set.
We also can not conditionally apply this by forcing the key at this
point, as this would change the language semantics.
Therefore, the name in the optimised representation is also carried as
`Value`.
Change-Id: I5be8a4c98ba19ebdfb7203a929f714a04492512e
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6101
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
There might be more logic in the future to encapsulate different
backing implementations of lists as well.
Change-Id: Ib7064fab48bf88b0c8913b0ecfa2108177c7c9fd
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6093
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
Deriving Ord/Eq is required for the ordered BTreeMaps. Once interning
is implemented this will require some extra magic for the sort order,
but that's fine.
Change-Id: I0c654648eb3609a4a01d84868c25f43a4d35bc2e
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6089
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
