use bstr::ByteSlice;use git_actor::SignatureRef; use crate::Snapshot; mod signature;pub use signature::{ResolvedSignature, Signature}; mod util;use util::EncodedStringRef; mod entry;pub(crate) use entry::EmailEntry; impl Snapshot {    /// Create a new snapshot from the given bytes buffer, ignoring all parse errors that may occur on a line-by-line basis.    ///    /// This is similar to what git does.    pub fn from_bytes(buf: &[u8]) -> Self {        Self::new(crate::parse_ignore_errors(buf))    }     /// Create a new instance from `entries`.    ///    /// These can be obtained using [crate::parse()].    pub fn new<'a>(entries: impl IntoIterator<Item = crate::Entry<'a>>) -> Self {        let mut snapshot = Self::default();        snapshot.merge(entries);        snapshot    }     /// Merge the given `entries` into this instance, possibly overwriting existing mappings with    /// new ones should they collide.    pub fn merge<'a>(&mut self, entries: impl IntoIterator<Item = crate::Entry<'a>>) -> &mut Self {        for entry in entries {            let old_email: EncodedStringRef<'_> = entry.old_email.into();            assert!(                entry.new_name.is_some() || entry.new_email.is_some(),                "BUG: encountered entry without any mapped/new name or email."            );            match self                .entries_by_old_email                .binary_search_by(|e| e.old_email.cmp_ref(old_email))            {                Ok(pos) => self.entries_by_old_email[pos].merge(entry),                Err(insert_pos) => {                    self.entries_by_old_email.insert(insert_pos, entry.into());                }            };        }        self    }     /// Transform our acceleration structure into a list of entries.    ///    /// Note that the order is different from how they were obtained initially, and are explicitly ordered by    /// (old_email, old_name).    pub fn entries(&self) -> Vec<crate::Entry<'_>> {        let mut out = Vec::with_capacity(self.entries_by_old_email.len());        for entry in &self.entries_by_old_email {            if entry.new_email.is_some() || entry.new_name.is_some() {                out.push(crate::Entry {                    new_name: entry.new_name.as_ref().map(|b| b.as_bstr()),                    new_email: entry.new_email.as_ref().map(|b| b.as_bstr()),                    old_name: None,                    old_email: entry.old_email.as_bstr(),                });            }             for name_entry in &entry.entries_by_old_name {                out.push(crate::Entry {                    new_name: name_entry.new_name.as_ref().map(|b| b.as_bstr()),                    new_email: name_entry.new_email.as_ref().map(|b| b.as_bstr()),                    old_name: name_entry.old_name.as_bstr().into(),                    old_email: entry.old_email.as_bstr(),                });            }        }        out    }     /// Try to resolve `signature` by its contained email and name and provide resolved/mapped names as reference.    /// Return `None` if no such mapping was found.    ///    /// Note that opposed to what git seems to do, we also normalize the case of email addresses to match the one    /// given in the mailmap. That is, if `Alex@example.com` is the current email, it will be matched and replaced with    /// `alex@example.com`. This leads to better mapping results and saves entries in the mailmap.    ///    /// This is the fastest possible lookup as there is no allocation.    pub fn try_resolve_ref(&self, signature: git_actor::SignatureRef<'_>) -> Option<ResolvedSignature<'_>> {        let email: EncodedStringRef<'_> = signature.email.into();        let pos = self            .entries_by_old_email            .binary_search_by(|e| e.old_email.cmp_ref(email))            .ok()?;        let entry = &self.entries_by_old_email[pos];         let name: EncodedStringRef<'_> = signature.name.into();         match entry.entries_by_old_name.binary_search_by(|e| e.old_name.cmp_ref(name)) {            Ok(pos) => {                let name_entry = &entry.entries_by_old_name[pos];                ResolvedSignature::try_new(                    name_entry.new_email.as_ref(),                    entry.old_email.as_bstr(),                    signature.email,                    name_entry.new_name.as_ref(),                )            }            Err(_) => ResolvedSignature::try_new(                entry.new_email.as_ref(),                entry.old_email.as_bstr(),                signature.email,                entry.new_name.as_ref(),            ),        }    }     /// Try to resolve `signature` by its contained email and name and provide resolved/mapped names as owned signature,    /// with the mapped name and/or email replaced accordingly.    ///    /// Return `None` if no such mapping was found.    pub fn try_resolve(&self, signature: git_actor::SignatureRef<'_>) -> Option<git_actor::Signature> {        self.try_resolve_ref(signature)            .map(|new| enriched_signature(signature, new).into())    }     /// Like [`try_resolve()`][Snapshot::try_resolve()], but always returns an owned signature, which might be a copy    /// of `signature` if no mapping was found.    ///    /// Note that this method will always allocate.    pub fn resolve(&self, signature: git_actor::SignatureRef<'_>) -> git_actor::Signature {        self.try_resolve(signature).unwrap_or_else(|| signature.to_owned())    }     /// Like [`try_resolve()`][Snapshot::try_resolve()], but always returns a special copy-on-write signature, which contains    /// changed names or emails as `Cow::Owned`, or `Cow::Borrowed` if no mapping was found.    pub fn resolve_cow<'a>(&self, signature: git_actor::SignatureRef<'a>) -> Signature<'a> {        self.try_resolve_ref(signature)            .map(|new| enriched_signature(signature, new))            .unwrap_or_else(|| signature.into())    }} fn enriched_signature<'a>(    SignatureRef { name, email, time }: SignatureRef<'a>,    new: ResolvedSignature<'_>,) -> Signature<'a> {    match (new.email, new.name) {        (Some(new_email), Some(new_name)) => Signature {            email: new_email.to_owned().into(),            name: new_name.to_owned().into(),            time,        },        (Some(new_email), None) => Signature {            email: new_email.to_owned().into(),            name: name.into(),            time,        },        (None, Some(new_name)) => Signature {            email: email.into(),            name: new_name.to_owned().into(),            time,        },        (None, None) => unreachable!("BUG: ResolvedSignatures don't exist here when nothing is set"),    }}