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2024-03-29Document ExprLambda fieldsJade Lovelace
We got confused what formals did and had to briefly figure it out. We should just have docs, so these are some. Change-Id: If3e794a401e69d022785cbfa0b0c2e2284f41f58
2024-03-18use byte indexed locations for PosIdxeldritch horrors
we now keep not a table of all positions, but a table of all origins and their sizes. position indices are now direct pointers into the virtual concatenation of all parsed contents. this slightly reduces memory usage and time spent in the parser, at the cost of not being able to report positions if the total input size exceeds 4GiB. this limit is not unique to nix though, rustc and clang also limit their input to 4GiB (although at least clang refuses to process inputs that are larger, we will not). this new 4GiB limit probably will not cause any problems for quite a while, all of nixpkgs together is less than 100MiB in size and already needs over 700MiB of memory and multiple seconds just to parse. 4GiB worth of input will easily take multiple minutes and over 30GiB of memory without even evaluating anything. if problems *do* arise we can probably recover the old table-based system by adding some tracking to Pos::Origin (or increasing the size of PosIdx outright), but for time being this looks like more complexity than it's worth. since we now need to read the entire input again to determine the line/column of a position we'll make unsafeGetAttrPos slightly lazy: mostly the set it returns is only used to determine the file of origin of an attribute, not its exact location. the thunks do not add measurable runtime overhead. notably this change is necessary to allow changing the parser since apparently nothing supports nix's very idiosyncratic line ending choice of "anything goes", making it very hard to calculate line/column positions in the parser (while byte offsets are very easy). (cherry picked from commit 5d9fdab3de0ee17c71369ad05806b9ea06dfceda) Change-Id: Ie0b2430cb120c09097afa8c0101884d94f4bbf34
2024-03-10add doc comment justifying ExprInheritFromeldritch horrors
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com> (cherry picked from commit f24e445bc024cfd3c26be5f061280af549321c22) Change-Id: I7acda5d5c34c0914a78adc2385d32782c4c275cd
2024-03-10remove ExprAttrs::AttrDef::inheritedeldritch horrors
it's no longer widely used and has a rather confusing meaning now that inherit-from is handled very differently. (cherry picked from commit 1cd87b7042d14aae1fafa47b1c28db4c5bd20de7) Change-Id: I90bbebddf06762960d8ca4f621cf042ce8ae83f9
2024-03-10evaluate inherit (from) exprs only once per directiveeldritch horrors
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
2024-03-10use the same bindings print for ExprAttrs and ExprLeteldritch horrors
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 6c08fba533ef31cad2bdc03ba72ecf58dc8ee5a0) Change-Id: Ia887f629305645bb8a165fbbc0d32e620912595a
2024-03-10add ExprAttrs::AttrDef::chooseByKindeldritch horrors
in place of inherited() — not quite useful yet since we don't distinguish plain and inheritFrom attr kinds so far. (cherry picked from commit 1f542adb3e18e7078e6a589182a53a47d971748a) Change-Id: If948c9d43e875de18f213a73a06a36f7c335b536
2024-03-10preserve information about whether/how an attribute was inheritedeldritch horrors
(cherry picked from commit c66ee57edc6cac3571bfbf77d0c0ea4d25b4e805) Change-Id: Ie8606a8b2f5946c87dd4d16b7b46203e199a4cc1
2024-03-09libexpr: Support structured error classeseldritch horrors
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
2024-03-09Move `PodIdx` to `pos-idx.hh` and `PosTable` to `pos-table.hh`eldritch horrors
(cherry picked from commit c62c21e29af20f1c14a59ab37d7a25dd0b70f69e) Change-Id: Id4ea2fc33b0874b2f1f2a32cabcbeb0afa26808f
2024-03-09don't repeatedly look up ast internal symbolseldritch horrors
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
2024-03-05Merge pull request #9634 from 9999years/combine-abstract-pos-and-poseldritch horrors
Combine `AbstractPos`, `PosAdapter`, and `Pos` (cherry picked from commit 113499d16fc87d53b73fb62fe6242154909756ed) === this is a bit cursed because originally it was based on InputAccessor code that we don't have and moved/patched features we likewise don't have (fetchToStore caching, all the individual accessors, ContentAddressMethod). the commit is adjusted accordingly to match (remove caching, ignore accessors, use FileIngestionMethod). note that `state.rootPath . CanonPath == abs` and computeStorePathForPath works relative to cwd, so the slight rewrite in the moved fetchToStore is legal. Change-Id: I05fd340c273f0bcc8ffabfebdc4a88b98083bce5
2024-03-04Merge pull request #9681 from edolstra/eval-optimisationseldritch horrors
Optimize empty list constants (cherry picked from commit 315aade89d00c692715e5953c36a1b7d6528b703) Change-Id: I0f28ef8a27ccedc45acf44243eec9dc35b733300
2024-03-04Merge pull request #9658 from pennae/env-dieteldritch horrors
reduce the size of Env by one pointer (cherry picked from commit 83f5622545a2fc31eb7e7d5105f64ed6dd3058b3) Change-Id: I5636290526d0165cfc61aee1e7a5b94db4a26cef
2024-03-04Merge pull request #9582 from pennae/misc-optseldritch horrors
a packet of small optimizations (cherry picked from commit ee439734e924eb337a869ff2e48aff8b989198bc) Change-Id: I125d870710750a32a0dece48f39a3e9132b0d023
2024-03-04Merge pull request #9555 from 9999years/positions-in-errorseldritch horrors
Pass positions when evaluating (cherry picked from commit c8458bd731eb1c74159bebe459ea00165e056b65) Change-Id: I1b4a5d58973be6264ffdb23b4492da200fdb71be
2024-03-04Merge pull request #9029 from inclyc/users/lyc/pass-value-2Eelco Dolstra
libexpr: const rvalue reference -> value for nix::Expr nodes (cherry picked from commit de99647b9c66219b2e7bc698a62377cc4f6148f6) Change-Id: I96baf96b0a17e401548a926a7015f85e11d7c459
2023-04-17Merge remote-tracking branch 'upstream/master' into source-pathRobert Hensing
2023-04-07Finish converting existing comments for internal API docs (#8146)John Ericson
* Finish converting existing comments for internal API docs 99% of this was just reformatting existing comments. Only two exceptions: - Expanded upon `BuildResult::status` compat note - Split up file-level `symbol-table.hh` doc comments to get per-definition docs Also fixed a few whitespace goofs, turning leading tabs to spaces and removing trailing spaces. Picking up from #8133 * Fix two things from comments * Use triple-backtick not indent for `dumpPath` * Convert GNU-style `\`..'` quotes to markdown style in API docs This will render correctly.
2023-04-06Origin: Use SourcePathEelco Dolstra
2023-03-31Ensure all headers have `#pragma once` and are in API docsJohn Ericson
`///@file` makes them show up in the internal API dos. A tiny few were missing `#pragma once`.
2023-02-16ExprOpHasAttr,ExprSelect,stripIndentation,binds,formals: delete losts objectsEt7f3
We are looking for *$ because it indicate that it was constructed with a new but not release. De-referencing shallow copy so deleting as whole might create dangling pointer that's why we move it so we delete a empty containers + the nice perf boost.
2023-02-12ExprString: Avoid copy of stringEt7f3
2023-01-19Revert "Revert "Merge pull request #6204 from layus/coerce-string""Guillaume Maudoux
This reverts commit 9b33ef3879a764bed4cc2404a08344c3a697a646.
2023-01-18Revert "Merge pull request #6204 from layus/coerce-string"Robert Hensing
This reverts commit a75b7ba30f1e4f8b15e810fd18e63ee9552e0815, reversing changes made to 9af16c5f742300e831a2cc400e43df1e22f87f31.
2023-01-02Merge remote-tracking branch 'origin/master' into coerce-stringEelco Dolstra
2022-12-13Restore display of source lines for stdin/string inputsEelco Dolstra
2022-12-13Introduce AbstractPosEelco Dolstra
This makes the position object used in exceptions abstract, with a method getSource() to get the source code of the file in which the error originated. This is needed for lazy trees because source files don't necessarily exist in the filesystem, and we don't want to make libutil depend on the InputAccessor type in libfetcher.
2022-09-07WIP: broken merge but need a git checkpointGuillaume Maudoux
2022-06-02Shut up clang warningsEelco Dolstra
2022-05-26Remove pre-C++11 hackinessEelco Dolstra
2022-05-22commentsBen Burdette
2022-05-19'debugMode'Ben Burdette
2022-05-19de-const evalState exceptionsBen Burdette
2022-05-19Merge branch 'debug-exploratory-PR' into debuggerHook-eval-argBen Burdette
2022-05-19use an expr->StaticEnv table in evalStateBen Burdette
2022-05-16first whack at passing evalState as an arg to debuggerHook.Ben Burdette
2022-05-05Style fixesEelco Dolstra
In particular, use std::make_shared and enumerate(). Also renamed some fields to fit naming conventions.
2022-04-29incorporate PosIdx changes, symbol changes.Ben Burdette
2022-04-29Merge remote-tracking branch 'origin/master' into coerce-stringGuillaume Maudoux
2022-04-28Merge branch 'master' into debug-merge-masterBen Burdette
2022-04-26Don't pass Symbol by referenceEelco Dolstra
Since Symbol is just an integer, passing it by const reference is never advantageous.
2022-04-25rename SymbolIdx -> Symbol, Symbol -> SymbolStrpennae
after #6218 `Symbol` no longer confers a uniqueness invariant on the string it wraps, it is now possible to create multiple symbols that compare equal but whose string contents have different addresses. this guarantee is now only provided by `SymbolIdx`, leaving `Symbol` only as a string wrapper that knows about the intricacies of how symbols need to be formatted for output. this change renames `SymbolIdx` to `Symbol` to restore the previous semantics of `Symbol` to that name. we also keep the wrapper type and rename it to `SymbolStr` instead of returning plain strings from lookups into the symbol table because symbols are formatted for output in many places. theoretically we do not need `SymbolStr`, only a function that formats a string for output as a symbol, but having to wrap every symbol that appears in a message into eg `formatSymbol()` is error-prone and inconvient.
2022-04-22Move ChunkedVector to its own headerThéophane Hufschmitt
2022-04-21store Symbols in a table as well, like positionspennae
this slightly increases the amount of memory used for any given symbol, but this increase is more than made up for if the symbol is referenced more than once in the EvalState that holds it. on average every symbol should be referenced at least twice (once to introduce a binding, once to use it), so we expect no increase in memory on average. symbol tables are limited to 2³² entries like position tables, and similar arguments apply to why overflow is not likely: 2³² symbols would require as many string instances (at 24 bytes each) and map entries (at 24 bytes or more each, assuming that the map holds on average at most one item per bucket as the docs say). a full symbol table would require at least 192GB of memory just for symbols, which is well out of reach. (an ofborg eval of nixpks today creates less than a million symbols!)
2022-04-21don't use Symbol in Pos to represent a pathpennae
PosTable deduplicates origin information, so using symbols for paths is no longer necessary. moving away from path Symbols also reduces the usage of symbols for things that are not keys in attribute sets, which will become important in the future when we turn symbols into indices as well.
2022-04-21replace most Pos objects/ptrs with indexes into a position tablepennae
Pos objects are somewhat wasteful as they duplicate the origin file name and input type for each object. on files that produce more than one Pos when parsed this a sizeable waste of memory (one pointer per Pos). the same goes for ptr<Pos> on 64 bit machines: parsing enough source to require 8 bytes to locate a position would need at least 8GB of input and 64GB of expression memory. it's not likely that we'll hit that any time soon, so we can use a uint32_t index to locate positions instead.
2022-04-07Merge remote-tracking branch 'upstream/master' into upstream-mergeBen Burdette
2022-03-25add DebugTrace for errorBen Burdette
2022-03-18Merge remote-tracking branch 'origin/master' into coerce-stringGuillaume Maudoux