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
deduplication does not currently work fully, showing derivations
multiple times if they have different underlying values. this can happen
by selecting the same derivation twice for two different attributes of a
set, using inherit-from (which reduces to the previous), importing
nixpkgs twice, or any other number of things.
since users already have to deal with duplicates for this reason it
won't hurt to add *more* duplicates. the alternative would be to
deduplicate fully, which would drop derivations that are currently
returned and those pose a regression risk.
Change-Id: I64b397351237e10375d270f1bddecb71f62aa131
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 ecf8b12d60)
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 6c08fba533)
Change-Id: Ia887f629305645bb8a165fbbc0d32e620912595a
in place of inherited() — not quite useful yet since we don't
distinguish plain and inheritFrom attr kinds so far.
(cherry picked from commit 1f542adb3e)
Change-Id: If948c9d43e875de18f213a73a06a36f7c335b536
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
Do not skip any stack frames when `--show-trace` is given
(cherry picked from commit 0b47783d0a879875d558f0b56e49584f25ceb2d0)
Change-Id: Ia0f18266dbcf97543110110c655c219c7a3e3270
Enter debugger on `builtins.trace` with an option
(cherry picked from commit 774e7ca5847ebc392eac2a124a8f12b24da4f65a)
Change-Id: If01e2110b3a128e639b05143227e365227d149f1
Pretty-print values in the REPL by printing each item in a list or
attrset on a separate line. When possible, single-item lists and
attrsets are printed on one line, as long as they don't contain a nested
list, attrset, or thunk.
Before:
```
{ attrs = { a = { b = { c = { }; }; }; }; list = [ 1 ]; list' = [ 1 2 3 ]; }
```
After:
```
{
attrs = {
a = {
b = {
c = { };
};
};
};
list = [ 1 ];
list' = [
1
2
3
];
}
```
(cherry picked from commit c0a15fb7d03dfb8f53bc6726c414bc88aa362592)
Change-Id: Ia2b41849165a5ddb63f7a8c272a2476b3e4292df
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`.
(cherry picked from commit c6a89c1a16)
Change-Id: Iced91ba4e00ca9e801518071fb43798936cbd05a
Catch `Error`, not `BaseError` in `ValuePrinter`
BaseError includes Interrupt. We probably don't want the value printer to tell you Ctrl-C was pressed while it was printing.
(cherry picked from commit c291d2d8dd)
Change-Id: I70b105bfb2f52a8f345ae0281d12f022aa36b14e
`nix eval` forces values and prints derivations as attribute sets, so
commands that print derivations (e.g. `nix eval nixpkgs#bash`) will
infinitely loop and segfault.
Printing derivations as `.drv` paths makes `nix eval` complete as
expected. Further work is needed, but this is better than a segfault.
(cherry picked from commit 4910d74086a85876e093136a0e8ebc547b467af7)
Change-Id: I8e1cb39c05db812080759ec183ee7a131760e6ea
these symbols are used a *lot*, so it makes sense to cache them. this
mostly increases clarity of the code (however clear one may wish to call
the parser desugaring here), but it also provides a small performance
benefit.
(cherry picked from commit 09a1128d9e)
Change-Id: I73d9f66be4555168e048cb2d542277251580c2d1
there's no reason the parser itself should be doing semantic analysis
like bindVars. split this bit apart (retaining the previous name in
EvalState) and have the parser really do *only* parsing, decoupled from
EvalState.
(cherry picked from commit b596cc9e79)
Change-Id: I481a7623afc783e9d28a6eb4627552cf8a780986
most EvalState and Expr members defined here could be elsewhere, where
they'd be easier to maintain (not being embedded in a file with arcane
syntax) and *somewhat* more faithfully placed according to the path of
the file they're defined in.
(cherry picked from commit e1aa585964)
Change-Id: Ibc704567462bb40f37cda05d8fadd465519db5f5
most instances of this being used do not refer to the "current"
position, sometimes not even to one reasonably close by. it could also
be called `makePos` instead, but `at` seems clear in context.
(cherry picked from commit 835a6c7bcf)
Change-Id: I17cab8a6cc14cac5b64624431957bfcf04140809
ParserState better describes what this struct really is. the parser
really does modify its state (most notably position and symbol tables),
so calling it that rather than obliquely "data" (which implies being
input only) makes sense.
(cherry picked from commit 0076056164)
Change-Id: I92feaec796530e1d4d0f7d4fba924229591cea95
since nix doesn't use the bison `error` terminal anywhere any invocation
of yyerror will immediately cause a failure. since we're *already*
leaking tons of memory whatever little bit bison allocates internally
doesn't much matter any more, and we'll be replacing the parser soon anyway.
coincidentally this now also matches the error behavior of URIs when
they are disabled or ~/ paths in pure eval mode, duplicate attr
detection etc.
(cherry picked from commit e8d9de967f)
Change-Id: I560c50d11dceddc2d7cf9ed2c6c631a309ce574e
Print the value in `error: cannot coerce` messages
(cherry picked from commit 5b7bfd2d6b)
===
test taken from 6e8d5983143ae576e3f4b1d2954a5267f2943a49; it was added
previously (and not backported because its pr was a mostly-revert), but
it's useful to have around.
Change-Id: Icbd14b55e3610ce7b774667bf14b82e6dc717982
Just `stdenv.isDarwin` isn't enough because it doesn't apply to the
build platform, which mean that cross packages building from darwin to
another platform will have `isDarwin` set to false.
Replace it by `stdenv.buildPlatform.isDarwin`.
(cherry picked from commit a0cb75d96f76a3be48b9319e26d8ad78ef4e4525)
(h/t jade for finding this one)
Change-Id: If3cb74e6feaa5d51de550d9a140c71683c2214cd
Previously, there were two mostly-identical value printers -- one in
`libexpr/eval.cc` (which didn't force values) and one in
`libcmd/repl.cc` (which did force values and also printed ANSI color
codes).
This PR unifies both of these printers into `print.cc` and provides a
`PrintOptions` struct for controlling the output, which allows for
toggling whether values are forced, whether repeated values are tracked,
and whether ANSI color codes are displayed.
Additionally, `PrintOptions` allows tuning the maximum number of
attributes, list items, and bytes in a string that will be displayed;
this makes it ideal for contexts where printing too much output (e.g.
all of Nixpkgs) is distracting. (As requested by @roberth in
https://github.com/NixOS/nix/pull/9554#issuecomment-1845095735)
Please read the tests for example output.
Future work:
- It would be nice to provide this function as a builtin, perhaps
`builtins.toStringDebug` -- a printing function that never fails would
be useful when debugging Nix code.
- It would be nice to support customizing `PrintOptions` members on the
command line, e.g. `--option to-string-max-attrs 1000`.
(cherry picked from commit 0fa08b4516, )
===
Restore ambiguous value printer for `nix-instantiate`
The Nix team has requested that this output format remain unchanged.
I've added a warning to the man page explaining that `nix-instantiate
--eval` output will not parse correctly in many situations.
(cherry picked from commit df84dd4d8d)
Change-Id: I7cca6b4b53cd0642f2d49af657d5676a8554c9f8