feat: handle RefLogLookup::Date

Author: dvtkrlbs

gix/src/revision/spec/parse/delegate/revision.rs

@@ -106,12 +106,51 @@ impl delegate::Revision for Delegate<'_> {
     fn reflog(&mut self, query: ReflogLookup) -> Option<()> {
         self.unset_disambiguate_call();
         match query {
-            ReflogLookup::Date(_date) => {
-                // TODO: actually do this - this should be possible now despite incomplete date parsing
-                self.err.push(Error::Planned {
-                    dependency: "remote handling and ref-specs are fleshed out more",
-                });
-                None
+            ReflogLookup::Date(date) => {
+                let r = match &mut self.refs[self.idx] {
+                    Some(r) => r.clone().attach(self.repo),
+                    val @ None => match self.repo.head().map(crate::Head::try_into_referent) {
+                        Ok(Some(r)) => {
+                            *val = Some(r.clone().detach());
+                            r
+                        }
+                        Ok(None) => {
+                            self.err.push(Error::UnbornHeadsHaveNoRefLog);
+                            return None;
+                        }
+                        Err(err) => {
+                            self.err.push(err.into());
+                            return None;
+                        }
+                    },
+                };
+
+                let mut platform = r.log_iter();
+                match platform.rev().ok().flatten() {
+                    Some(it) => match it
+                        .filter_map(Result::ok)
+                        .min_by_key(|l| (date - l.signature.time).abs())
+                    {
+                        Some(closest_line) => {
+                            self.objs[self.idx]
+                                .get_or_insert_with(HashSet::default)
+                                .insert(closest_line.new_oid);
+                            Some(())
+                        }
+                        None => {
+                            // do we need an another error variant?
+                            self.err.push(Error::SingleNotFound);
+                            None
+                        }
+                    },
+                    None => {
+                        self.err.push(Error::MissingRefLog {
+                            reference: r.name().as_bstr().into(),
+                            action: "lookup entry",
+                        });
+                        None
+                    }
+                }
             }
             ReflogLookup::Entry(no) => {
                 let r = match &mut self.refs[self.idx] {

gix/src/revision/spec/parse/types.rs

@@ -77,8 +77,6 @@ pub enum Error {
         direction: remote::Direction,
         source: Box<dyn std::error::Error + Send + Sync + 'static>,
     },
-    #[error("This feature will be implemented once {dependency}")]
-    Planned { dependency: &'static str },
     #[error("Reference {reference:?} does not have a reference log, cannot {action}")]
     MissingRefLog { reference: BString, action: &'static str },
     #[error("HEAD has {available} prior checkouts and checkout number {desired} is out of range")]
@@ -194,4 +192,6 @@ pub enum Error {
     Walk(#[from] crate::revision::walk::Error),
     #[error("Spec does not contain a single object id")]
     SingleNotFound,
+    #[error("Reflog does not contain any entries")]
+    EmptyReflog
 }

gix/tests/gix/revision/spec/from_bytes/reflog.rs

@@ -1,7 +1,4 @@
-use gix::{
-    prelude::ObjectIdExt,
-    revision::{spec::parse::Error, Spec},
-};
+use gix::{prelude::ObjectIdExt, revision::Spec};
 
 use crate::{
     revision::spec::from_bytes::{parse_spec, parse_spec_no_baseline, repo},
@@ -78,10 +75,13 @@ fn by_index() {
 }
 
 #[test]
-fn by_date_is_planned_until_git_date_crate_is_implements_parsing() {
+fn by_date() {
     let repo = repo("complex_graph").unwrap();
-    assert!(matches!(
-        parse_spec_no_baseline("main@{1979-02-26 18:30:00}", &repo).unwrap_err(),
-        Error::Planned { .. }
-    ));
+
+    let spec = parse_spec_no_baseline("main@{1979-02-26 18:30:00}", &repo).unwrap();
+
+    assert_eq!(
+        spec,
+        Spec::from_id(hex_to_id("9f9eac6bd1cd4b4cc6a494f044b28c985a22972b").attach(&repo))
+    );
 }