Deprecated warnings in cargo output for rustc-serialize feature #174
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
quodlibetor
force-pushed
the
deprecated-warnings-for-rustc_serialize
branch
2 times, most recently
from
8484038
to
94c1808
Compare
Unfortunately due to rust-lang/rust#39935 placing the annotation on the `impl`s of `Encodable`/`Decodable` for the various items have no effect whatsoever, so we need to place it on some type that chrono actually uses internally. The only *type* that I can find that only exists for rustc-serialize only is the `TsSeconds` struct. So, marking TsSeconds deprecated causes Chrono's internal uses of `TsSeconds` to emit deprecation warnings, both in our builds and for packages that specify Chrono as a dependency with the `rustc-serialize` feature active. This means that the current commit will cause a `warning: use of deprecated item: RustcSerialize will be removed before chrono 1.0, use Serde instead` to appear in `cargo build` output. Unfortunately I don't think that it's possible for downstream crates to disable the warning the warning in any way other than actually switching to Serde or using an older chrono. That's the reason for all the `#[allow(deprecated)]` through the code, it means that the warning appears almost exactly once, instead of dozens of times.
quodlibetor
force-pushed
the
deprecated-warnings-for-rustc_serialize
branch
from
94c1808
to
39ca2e6
Compare
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Unfortunately due to rust-lang/rust#39935 placing the annotation on the
implsof
Encodable/Decodablefor the various items have no effect whatsoever, sowe need to place it on some type that chrono actually uses internally. The only
type that I can find that only exists for rustc-serialize only is the
TsSecondsstruct.So, marking TsSeconds deprecated causes Chrono's internal uses of
TsSecondsto emit deprecation warnings, both in our builds and for packages that specify
Chrono as a dependency with the
rustc-serializefeature active. This meansthat the current commit will cause a
warning: use of deprecated item: RustcSerialize will be removed before chrono 1.0, use Serde insteadto appearin
cargo buildoutput.Unfortunately I don't think that it's possible for downstream crates to disable
the warning the warning in any way other than actually switching to Serde or
using an older chrono. That's the reason for all the
#[allow(deprecated)]through the code, it means that the warning appears almost exactly once,
instead of dozens of times.