Fixes
$ nix flake metadata --store /tmp/nix nixpkgs
error: path '/tmp/nix/nix/store/65xpqkz92d9j7k5ric4z8lzhiigxsfbg-source/flake.nix' is not in the Nix store
This has been broken since 598deb2b23.
We're not replacing `Path` in exposed definitions in many cases, but
just adding alternatives. This will allow us to "top down" change `Path`
to `std::fileysystem::path`, and then we can remove the `Path`-using
utilities which will become unused.
Also add some test files which we forgot to include in the libutil unit
tests `meson.build`.
Co-Authored-By: siddhantCodes <siddhantk232@gmail.com>
Empty attributes are probably not well supported, but the least we
could do is leave a hint.
Attribute path rendering and parsing should be done according to
Nix expression syntax in my opinion.
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.
Thunks are now overwritten by a helper function
`Value::finishValue(newType, payload)` (where `payload` is the
original anonymous union inside `Value`). This helps to ensure we
never update a value elsewhere, since that would be incompatible with
parallel evaluation (i.e. after a value has transitioned from being a
thunk to being a non-thunk, it should be immutable).
There were two places where this happened: `Value::mkString()` and
`ExprAttrs::eval()`.
This PR also adds a bunch of accessor functions for value contents,
like `Value::integer()` to access the integer field in the union.
* Convert all InputScheme::fetch() methods to getAccessor().
* Add checkLocks() method for checking lock attributes.
* Rename fetch() to fetchToStore().
This is the case for e.g. dirty Git workdirs, where we would get
$ nix flake metadata
Resolved URL: git+file:///home/eelco/Dev/nix-master
Locked URL: git+file:///home/eelco/Dev/nix-master
Flakes still reside in the Nix store (so there shouldn't be any change
in behaviour), but they are now accessed via the rootFS
accessor. Since rootFS implements access checks, we no longer have to
worry about flake.{nix,lock} or their parents being symlinks that
escape from the flake.
Extracted from the lazy-trees branch.
It's better to just check whether the input has all the attributes
needed to consider itself locked (e.g. whether a Git input has an
'rev' attribute).
Also, the 'locked' field was actually incorrect for Git inputs: it
would be set to true even for dirty worktrees. As a result, we got
away with using fetchTree() internally even though fetchTree()
requires a locked input in pure mode. In particular, this allowed
'--override-input' to work by accident.
The fix is to pass a set of "overrides" to call-flake.nix for all the
unlocked inputs (i.e. the top-level flake and any --override-inputs).
While preparing PRs like #9753, I've had to change error messages in
dozens of code paths. It would be nice if instead of
EvalError("expected 'boolean' but found '%1%'", showType(v))
we could write
TypeError(v, "boolean")
or similar. Then, changing the error message could be a mechanical
refactor with the compiler pointing out places the constructor needs to
be changed, rather than the error-prone process of grepping through the
codebase. Structured errors would also help prevent the "same" error
from having multiple slightly different messages, and could be a first
step towards error codes / an error index.
This PR reworks the exception infrastructure in `libexpr` to
support exception types with different constructor signatures than
`BaseError`. Actually refactoring the exceptions to use structured data
will come in a future PR (this one is big enough already, as it has to
touch every exception in `libexpr`).
The core design is in `eval-error.hh`. Generally, errors like this:
state.error("'%s' is not a string", getAttrPathStr())
.debugThrow<TypeError>()
are transformed like this:
state.error<TypeError>("'%s' is not a string", getAttrPathStr())
.debugThrow()
The type annotation has moved from `ErrorBuilder::debugThrow` to
`EvalState::error`.
This does not yet resolve the coupling between packages and
derivations, but it makes the code more consistent with the
terminology, and it accentuates places where the coupling is
obvious, such as
auto drvPath = packageInfo.queryDrvPath();
if (!drvPath)
throw Error("'%s' is not a derivation", what());
... which isn't wrong, and in my opinion, doesn't even look
wrong, because it just reflects the current logic.
However, I do like that we can now start to see in the code that
this coupling is perhaps a bit arbitrary.
After this rename, we can bring the DerivingPath concept into type
and start to lift this limitation.
* Factor out the default `MultiCommand` behavior
All the `MultiCommand`s had (nearly) the same behavior when called
without a subcommand.
Factor out this behavior into the `NixMultiCommand` class.
* Display the list of available subcommands when none is specified
Whenever a user runs a command that excepts a subcommand, add the list
of available subcommands to the error message.
* Print the multi-command lists as Markdown lists
This takes more screen real estate, but is also much more readable than
a comma-separated list
This builds on #8817, to add additional UX help for people with existing
muscle memory (or shell history) with --update-input and tries to gently
guide them towards the newly evolved CLI UI.
Co-authored-by: Cole Helbling <cole.e.helbling@outlook.com>
