feat: handle ReflogLookup::Date

gix-ref/src/store/file/log/iter.rs

@@ -92,7 +92,7 @@ impl Platform<'_, '_> {
     /// Return a forward iterator over all log-lines, most recent to oldest.
     pub fn rev(&mut self) -> std::io::Result<Option<log::iter::Reverse<'_, std::fs::File>>> {
         self.buf.clear();
-        self.buf.resize(512, 0);
+        self.buf.resize(1024 * 4, 0);
         self.store
             .reflog_iter_rev(self.name, &mut self.buf)
             .map_err(must_be_io_err)
@@ -219,7 +219,7 @@ where
                         if npos == last_read_pos {
                             return Some(Err(std::io::Error::new(
                                 std::io::ErrorKind::Other,
-                                "buffer too small for line size",
+                                format!("buffer too small for line size, got until {:?}", self.buf.as_bstr()),
                             )
                             .into()));
                         }

gix-ref/tests/refs/file/log.rs

@@ -81,7 +81,7 @@ mod iter {
                             .source()
                             .expect("source")
                             .to_string(),
-                        "buffer too small for line size"
+                        "buffer too small for line size, got until \"0000000000000000 134385f6d781b7e97062102c6a483440bfda2a03 committer <committer@example.com> 946771200 +0000\\tcommit (initial): c1\""
                     );
                     assert!(iter.next().is_none(), "iterator depleted");
                 }
@@ -90,9 +90,9 @@ mod iter {
         }
 
         mod with_buffer_big_enough_for_largest_line {
-            use gix_ref::log::Line;
-
+            use crate::file::log::iter::reflog;
             use crate::hex_to_id;
+            use gix_ref::log::Line;
 
             #[test]
             fn single_line() -> crate::Result {
@@ -157,6 +157,24 @@ mod iter {
                 }
                 Ok(())
             }
+
+            #[test]
+            fn realistic_logs_can_be_read_completely() -> crate::Result {
+                let log = reflog("refs/heads/old")?;
+                let mut buf = Vec::with_capacity(16 * 1024);
+                for size in [2048, 3000, 4096, 8192, 16384] {
+                    buf.resize(size, 0);
+                    let read = std::io::Cursor::new(&*log);
+                    let count = gix_ref::file::log::iter::reverse(read, &mut buf)?
+                        .filter_map(Result::ok)
+                        .count();
+                    assert_eq!(
+                        count, 581,
+                        "All entries must be readable as long as the buffer can fit a whole line"
+                    );
+                }
+                Ok(())
+            }
         }
     }
     mod forward {

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

@@ -105,59 +105,81 @@ 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::Entry(no) => {
-                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(mut it) => match it.nth(no).and_then(Result::ok) {
-                        Some(line) => {
-                            self.objs[self.idx]
-                                .get_or_insert_with(HashSet::default)
-                                .insert(line.new_oid);
-                            Some(())
-                        }
-                        None => {
-                            let available = platform.rev().ok().flatten().map_or(0, Iterator::count);
-                            self.err.push(Error::RefLogEntryOutOfRange {
-                                reference: r.detach(),
-                                desired: no,
-                                available,
+        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(mut it) => match query {
+                ReflogLookup::Date(date) => {
+                    let mut last = None;
+                    let id_to_insert = match it
+                        .filter_map(Result::ok)
+                        .inspect(|d| {
+                            last = Some(if d.previous_oid.is_null() {
+                                d.new_oid
+                            } else {
+                                d.previous_oid
                             });
-                            None
-                        }
-                    },
+                        })
+                        .find(|l| l.signature.time.seconds <= date.seconds)
+                    {
+                        Some(closest_line) => closest_line.new_oid,
+                        None => match last {
+                            None => {
+                                self.err.push(Error::EmptyReflog);
+                                return None;
+                            }
+                            Some(id) => id,
+                        },
+                    };
+                    self.objs[self.idx]
+                        .get_or_insert_with(HashSet::default)
+                        .insert(id_to_insert);
+                    Some(())
+                }
+                ReflogLookup::Entry(no) => match it.nth(no).and_then(Result::ok) {
+                    Some(line) => {
+                        self.objs[self.idx]
+                            .get_or_insert_with(HashSet::default)
+                            .insert(line.new_oid);
+                        Some(())
+                    }
                     None => {
-                        self.err.push(Error::MissingRefLog {
-                            reference: r.name().as_bstr().into(),
-                            action: "lookup entry",
+                        let available = platform.rev().ok().flatten().map_or(0, Iterator::count);
+                        self.err.push(Error::RefLogEntryOutOfRange {
+                            reference: r.detach(),
+                            desired: no,
+                            available,
                         });
                         None
                     }
-                }
+                },
+            },
+            None => {
+                self.err.push(Error::MissingRefLog {
+                    reference: r.name().as_bstr().into(),
+                    action: match query {
+                        ReflogLookup::Entry(_) => "lookup reflog entry by index",
+                        ReflogLookup::Date(_) => "lookup reflog entry by date",
+                    },
+                });
+                None
             }
         }
     }

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,
 }