NixOS/nix
NixOS/nix
1
0
Fork 0
mirror of https://github.com/NixOS/nix synced 2024-09-19 10:50:24 -04:00
Code Activity

document where the value of builtins.nixPath comes from (#9113)

Browse source 
* document default values for `nix-path`

also note how it's overridden and note the effect of `restrict-eval`
This commit is contained in:
Valentin Gagarin 2024-03-09 18:57:57 +01:00 committed by GitHub
parent 3120fef01b
commit ac730622e8
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
2 changed files with 20 additions and 11 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

23
src/libexpr/eval-settings.hh
View file

@ -21,11 +21,24 @@ struct EvalSettings : Config
Setting<Strings> nixPath{
this, getDefaultNixPath(), "nix-path",
R"(
List of directories to be searched for `<...>` file references
List of search paths to use for [lookup path](@docroot@/language/constructs/lookup-path.md) resolution.
This setting determines the value of
[`builtins.nixPath`](@docroot@/language/builtin-constants.md#builtins-nixPath) and can be used with [`builtins.findFile`](@docroot@/language/builtin-constants.md#builtins-findFile).
In particular, outside of [pure evaluation mode](#conf-pure-eval), this determines the value of
[`builtins.nixPath`](@docroot@/language/builtin-constants.md#builtins-nixPath).
)"};
The default value is
```
$HOME/.nix-defexpr/channels
nixpkgs=$NIX_STATE_DIR/profiles/per-user/root/channels/nixpkgs
$NIX_STATE_DIR/profiles/per-user/root/channels
```
It can be overridden with the [`NIX_PATH` environment variable](@docroot@/command-ref/env-common.md#env-NIX_PATH) or the [`-I` command line option](@docroot@/command-ref/opt-common.md#opt-I).
> **Note**
>
> If [pure evaluation](#conf-pure-eval) is enabled, `nixPath` evaluates to the empty list `[ ]`.
)", {}, false};
Setting<std::string> currentSystem{
this, "", "eval-system",
@ -55,8 +68,6 @@ struct EvalSettings : Config
[`builtins.nixPath`](@docroot@/language/builtin-constants.md#builtins-nixPath),
or to URIs outside of
[`allowed-uris`](@docroot@/command-ref/conf-file.md#conf-allowed-uris).
Also the default value for [`nix-path`](#conf-nix-path) is ignored, such that only explicitly set search path entries are taken into account.
)"};
Setting<bool> pureEval{this, false, "pure-eval",

8
src/libexpr/primops.cc
View file

@ -1736,7 +1736,7 @@ static RegisterPrimOp primop_findFile(PrimOp {
- If the suffix is found inside that directory, then the entry is a match.
The combined absolute path of the directory (now downloaded if need be) and the suffix is returned.
[Lookup path](@docroot@/language/constructs/lookup-path.md) expressions can be [desugared](https://en.wikipedia.org/wiki/Syntactic_sugar) using this and [`builtins.nixPath`](@docroot@/language/builtin-constants.md#builtins-nixPath):
[Lookup path](@docroot@/language/constructs/lookup-path.md) expressions are [desugared](https://en.wikipedia.org/wiki/Syntactic_sugar) using this and [`builtins.nixPath`](@docroot@/language/builtin-constants.md#builtins-nixPath):
```nix
<nixpkgs>
@ -4570,11 +4570,9 @@ void EvalState::createBaseEnv()
addConstant("__nixPath", v, {
.type = nList,
.doc = R"(
List of search path entries used to resolve [lookup paths](@docroot@/language/constructs/lookup-path.md).
The value of the [`nix-path` configuration setting](@docroot@/command-ref/conf-file.md#conf-nix-path): a list of search path entries used to resolve [lookup paths](@docroot@/language/constructs/lookup-path.md).
Lookup path expressions can be
[desugared](https://en.wikipedia.org/wiki/Syntactic_sugar)
using this and
Lookup path expressions are [desugared](https://en.wikipedia.org/wiki/Syntactic_sugar) using this and
[`builtins.findFile`](./builtins.html#builtins-findFile):
```nix