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 c6a89c1a1659b31694c0fbcd21d78a6dd521c732)
Change-Id: Iced91ba4e00ca9e801518071fb43798936cbd05a
Don't print the first bracket in values in magenta in error messages
(cherry picked from commit 46a0625a40aef6946a35f92fdacf0e6b4a14414f)
Change-Id: I8435565c87db182116140eaeea9df1243e67ea94
Enter debugger more reliably in `let` expressions and function calls
(cherry picked from commit c4ed92fa6f836d3d8eb354a48c37a2f9eeecc3aa)
Change-Id: I16d0cad7e898feecd2399723b92ba8df67222fb4
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 c291d2d8dda38aa88b004e2ed05b28653c07e342)
Change-Id: I70b105bfb2f52a8f345ae0281d12f022aa36b14e
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 09a1128d9e2ff0ae6176784938047350d6f8a782)
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 b596cc9e7960b9256bcd557334d81e9d555be5a2)
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 e1aa585964c3d864ebff0030584f3349a539d615)
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 835a6c7bcfd0b22acc16f31de5fc7bb650d52017)
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 007605616477f4f0d8a0064c375b1d3cf6188ac5)
Change-Id: I92feaec796530e1d4d0f7d4fba924229591cea95
all of them need access to parser state in some way. make them members
to allow this without fussing so much.
(cherry picked from commit 1b09b80afac27c67157d4b315c237fa7bb9b8d08)
Change-Id: I3145c95666a5617b735eff7cb403c54c0fe86347
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 e8d9de967fe47a7f9324b0022a2ef50df59f419d)
Change-Id: I560c50d11dceddc2d7cf9ed2c6c631a309ce574e
this is a proper subset of Formals anyway, so let's just use those and
avoid the extra allocations and moves.
(cherry picked from commit f07388bf985c2440413f398cf93d5f5840d1ec8c)
Change-Id: I4508c9c9c918cbaaed649dc753eb86f5cafc7ab6
Print the value in `error: cannot coerce` messages
(cherry picked from commit 5b7bfd2d6b89d7dd5f54c1ca6c8072358d31a84e)
===
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
libexpr: print value of what is attempted to be called as function
(cherry picked from commit 50e5d7b883042852538371237e32a66bb22f0485)
Change-Id: I7cb6290bd8f244e83bfce3b2eed2a4c8b4f16a83
Print the value in `value is X while a Y is expected` error
(cherry picked from commit 5f72a97092da6af28a7d2b2a50d74e9d34fae7e1)
Change-Id: Idb4bc903ae59a0f5b6fb3b1da4d47970fe0a6efe
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 0fa08b451682fb3311fe58112ff05c4fe5bee3a4, )
===
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 df84dd4d8dd3fd6381ac2ca3064432ab31a16b79)
Change-Id: I7cca6b4b53cd0642f2d49af657d5676a8554c9f8
Qyriad
eldritch horrors
puck