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Avoid using cfg with destination-crate feature in proc-macro derive#132
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BenWiederhake wants to merge 1 commit intouutils:mainfrom
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Avoid using cfg with destination-crate feature in proc-macro derive#132BenWiederhake wants to merge 1 commit intouutils:mainfrom
BenWiederhake wants to merge 1 commit intouutils:mainfrom
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Quoting cargo:
using a cfg inside a derive macro will use the cfgs from the
destination crate and not the ones from the defining crate
In these two instances, the cfg was simply used to avoid emitting dead
code if the "complete" feature is not desired. By passing the "complete"
feature down to the derive crate and evaluating if there, we achieve the
same goal, without having to deal with suprisingly-valued and unexpected
cfgs downstream.
Alternatively, we could just remove the feature-flag and make it part of
the permanent API.
This was referenced Apr 12, 2025
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Quoting cargo:
In these two instances, the cfg was simply used to avoid emitting dead code if the "complete" feature is not desired. By passing the "complete" feature down to the derive crate and evaluating if there, we achieve the same goal, without having to deal with suprisingly-valued and unexpected cfgs downstream.
Discovered while trying to integrate uutils-args into coreutils: https://github.com/uutils/coreutils/actions/runs/14420666926/job/40442804575?pr=7739
This is not my favourite approach.
Alternatively, we could just remove the feature-flag and make it part of the permanent API, as implemented in #131.