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    use std::fmt;
    use std::fmt::Display;

    use serde_untagged::UntaggedEnumVisitor;

    use crate::core::PartialVersion;
    use crate::core::PartialVersionError;

    #[derive(PartialEq, Eq, PartialOrd, Ord, Hash, Clone, Debug, serde::Serialize)]
    #[serde(transparent)]
    pub struct RustVersion(PartialVersion);

    impl RustVersion {
        pub fn is_compatible_with(&self, rustc: &PartialVersion) -> bool {
            let msrv = self.0.to_caret_req();
            // Remove any pre-release identifiers for easier comparison
            let rustc = semver::Version {
                major: rustc.major,
                minor: rustc.minor.unwrap_or_default(),
                patch: rustc.patch.unwrap_or_default(),
                pre: Default::default(),
                build: Default::default(),
            };
            msrv.matches(&rustc)
        }

        pub fn into_partial(self) -> PartialVersion {
            self.0
        }

        pub fn as_partial(&self) -> &PartialVersion {
            &self.0
        }
    }

    impl std::str::FromStr for RustVersion {
        type Err = RustVersionError;

        fn from_str(value: &str) -> Result<Self, Self::Err> {
            let partial = value.parse::<PartialVersion>();
            let partial = partial.map_err(RustVersionErrorKind::PartialVersion)?;
            partial.try_into()
        }
    }

    impl TryFrom<semver::Version> for RustVersion {
        type Error = RustVersionError;

        fn try_from(version: semver::Version) -> Result<Self, Self::Error> {
            let version = PartialVersion::from(version);
            Self::try_from(version)
        }
    }

    impl TryFrom<PartialVersion> for RustVersion {
        type Error = RustVersionError;

        fn try_from(partial: PartialVersion) -> Result<Self, Self::Error> {
            if partial.pre.is_some() {
                return Err(RustVersionErrorKind::Prerelease.into());
            }
            if partial.build.is_some() {
                return Err(RustVersionErrorKind::BuildMetadata.into());
            }
            Ok(Self(partial))
        }
    }

    impl<'de> serde::Deserialize<'de> for RustVersion {
        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
        where
            D: serde::Deserializer<'de>,
        {
            UntaggedEnumVisitor::new()
                .expecting("SemVer version")
                .string(|value| value.parse().map_err(serde::de::Error::custom))
                .deserialize(deserializer)
        }
    }

    impl Display for RustVersion {
        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
            self.0.fmt(f)
        }
    }

    /// Error parsing a [`RustVersion`].
    #[derive(Debug, thiserror::Error)]
    #[error(transparent)]
    pub struct RustVersionError(#[from] RustVersionErrorKind);

    /// Non-public error kind for [`RustVersionError`].
    #[non_exhaustive]
    #[derive(Debug, thiserror::Error)]
    enum RustVersionErrorKind {
        #[error("unexpected prerelease field, expected a version like \"1.32\"")]
        Prerelease,

        #[error("unexpected build field, expected a version like \"1.32\"")]
        BuildMetadata,

        #[error(transparent)]
        PartialVersion(#[from] PartialVersionError),
    }

    #[cfg(test)]
    mod test {
        use super::*;

        #[test]
        fn is_compatible_with_rustc() {
            let cases = &[
                ("1", "1.70.0", true),
                ("1.30", "1.70.0", true),
                ("1.30.10", "1.70.0", true),
                ("1.70", "1.70.0", true),
                ("1.70.0", "1.70.0", true),
                ("1.70.1", "1.70.0", false),
                ("1.70", "1.70.0-nightly", true),
                ("1.70.0", "1.70.0-nightly", true),
                ("1.71", "1.70.0", false),
                ("2", "1.70.0", false),
            ];
            let mut passed = true;
            for (msrv, rustc, expected) in cases {
                let msrv: RustVersion = msrv.parse().unwrap();
                let rustc = PartialVersion::from(semver::Version::parse(rustc).unwrap());
                if msrv.is_compatible_with(&rustc) != *expected {
                    println!("failed: {msrv} is_compatible_with {rustc} == {expected}");
                    passed = false;
                }
            }
            assert!(passed);
        }

        #[test]
        fn is_compatible_with_workspace_msrv() {
            let cases = &[
                ("1", "1", true),
                ("1", "1.70", true),
                ("1", "1.70.0", true),
                ("1.30", "1", false),
                ("1.30", "1.70", true),
                ("1.30", "1.70.0", true),
                ("1.30.10", "1", false),
                ("1.30.10", "1.70", true),
                ("1.30.10", "1.70.0", true),
                ("1.70", "1", false),
                ("1.70", "1.70", true),
                ("1.70", "1.70.0", true),
                ("1.70.0", "1", false),
                ("1.70.0", "1.70", true),
                ("1.70.0", "1.70.0", true),
                ("1.70.1", "1", false),
                ("1.70.1", "1.70", false),
                ("1.70.1", "1.70.0", false),
                ("1.71", "1", false),
                ("1.71", "1.70", false),
                ("1.71", "1.70.0", false),
                ("2", "1.70.0", false),
            ];
            let mut passed = true;
            for (dep_msrv, ws_msrv, expected) in cases {
                let dep_msrv: RustVersion = dep_msrv.parse().unwrap();
                let ws_msrv = ws_msrv.parse::<RustVersion>().unwrap().into_partial();
                if dep_msrv.is_compatible_with(&ws_msrv) != *expected {
                    println!("failed: {dep_msrv} is_compatible_with {ws_msrv} == {expected}");
                    passed = false;
                }
            }
            assert!(passed);
        }
    }