lib/modules: Report error for unsupported t // { check = ...; }#454964
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t // { check = ...; }`t // { check = ...; }
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`check` can have a new place since the introduction of
merge.v2. This makes the // { check = ... } idiom unreliable.
In this PR we add checks to detect and report this.
merge.v2 introduced in:
NixOS#391544
Real world case:
https://hercules-ci.com/github/hercules-ci/hercules-ci-effects/jobs/875
MattSturgeon
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The dagOf type was using an ad-hoc `type // { check = ...; }` pattern
via `inherit (attrEquivalent) check`, which is incompatible with throw
introduced in NixOS/nixpkgs#454964.
This commit properly implements the v2 merge protocol for dagOf by:
- Making `check` a functor with `isV2MergeCoherent = true` that
delegates to the underlying attrsOf type's check function
- Making `merge` a functor with a `v2` attribute that properly
delegates to the underlying type's v2 merge implementation
This ensures compatibility with the v2 merge mechanism while
maintaining all existing dagOf functionality.
Fixes evaluation errors like:
error: The option '...' has a type `DAG of X' that uses
an ad-hoc `type // { check = ...; }' override, which is
incompatible with the v2 merge mechanism.
Signed-off-by: Austin Horstman <khaneliman12@gmail.com>
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checkcan have a new place since the introduction ofmerge.v2. This makes thet // { check = ...; }idiom unreliable.In this PR we add checks to detect and report this in cases where it breaks.
merge.v2introduced in:Real world case: hercules-ci-effects
I was lucky to unit test my type in a way that triggers it. Many people don't unit test types (I hope not most 🤨), and they'll have a harder time to figure this out.
Things done
passthru.tests.nixpkgs-reviewon this PR. See nixpkgs-review usage../result/bin/.Add a 👍 reaction to pull requests you find important.