In the common case, nix develop is running against a dirty checkout of a project.
This patch removes the warning about a dirty tree on nix develop only.
Close FH-736
This name is close to the Nixpkgs lib function `escapeShellArg`,
making it easier to find.
A friendlier function with the same behavior as lib could be added
later.
Fixes
../src/libstore/unix/build/derivation-builder.cc:1130:86: warning: the compiler can assume that the address of ‘nix::DerivationBuilderParams::drv’ will never be NULL [-Waddress]
1130 | if (useChroot && settings.preBuildHook != "" && dynamic_cast<const Derivation *>(&drv)) {
| ^~~~
Assuming this check was left over from the time `drv` could be a
`BasicDerivation`.
I split it out before to try to separate the building logic, but now we
have the much better `DerivationBuilder` abstraction for that. With that
change, I think `LocalDerivationGoal` has outlived its usefulness.
We just inline it back into `DerivationGoal`, and do so with minimal
`#ifdef` for Windows.
Note that the order of statements in `~DerivationGoal` is different than
it was after the `~LocalDerivationGoal` split, but it is *restored* to
the way it original was before --- evidently I did the split slightly
wrong, but nobody noticed, probably because the order doesn't actually
matter.
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
Now that `DerivationBuilder` is created after the underlying data has
already been initialized, we can just refer this data normally, with a
direct reference.
Only `parsedDrv` takes a (borrowing) pointer, because independent of
initialization the derivation may or may not have structured attrs.
This is needed to devirtualize them when they get passed to a
derivation or builtins.toFile. Arguably, since this builtin is unsafe,
we could just ignore this, but we may as well do the correct thing.
The building logic is now free of the scheduling logic!
(The interface between them is just what is in the new header. This
makes it much easier to audit, and shrink over time.)
We have a new `DerivationBuilder` struct, and `DerivationBuilderParams`
`DerivationBuilderCallbacks` supporting it.
`LocalDerivationGoal` doesn't subclass any of these, so we are ready to
now move them out to a new file!
Now, most of it is in two new functions:
`LocalDerivationGoal::{,un}repareBuild`.
This might seems like a step backwards from coroutines --- now we have
more functions, and are stuck with class vars --- but I don't think it
needs to be.
There's a few options here:
- (Re)introduce coroutines for the isolated building logic. We could use the
same coroutines types, or simpler ones specialized to this use-case.
The `tryLocalBuild` caller can still use `Goal::Co`, and just will
manually "pump" this inner coroutine.
- Return closures from each step. This is sort of like coroutines by
hand, but it still allows us to stop writing down the local variables
in each type.
Being able to fully-use RAII again would be very nice!
- Keep top-level first-order functions like now, but make more
functional. Instead of having one state object (`DerivationBuilder`)
for all steps (setup, run, teardown), we can have separate structs for
the live variables at each point we consume and return.
This at least avoids "are these variables active at this time?"
questions, but doesn't give us the full benefit of RAII as we must
manually ensure FIFO create/destroy orders still.
One thing to note is that by keeping the `outputLock` unlocking in
`tryLocalBuild`, we are arguably uncovering a rebuild scheduling vs
building distinction, as the output locks are pretty squarely a
scheduling concern. It's nice that the builder doesn't need to know
about them at all.
We had fields set to the same values before in our test data. This is
not a problem per-se, but does mean we wouldn't catch certain mixups.
Now, the fields are set to distinct values (where possible), which makes
the test more robust.
(cherry picked from commit a0b2b75f59)
We had fields set to the same values before in our test data. This is
not a problem per-se, but does mean we wouldn't catch certain mixups.
Now, the fields are set to distinct values (where possible), which makes
the test more robust.
