change!: Use the gix-object::Find trait

Author: Byron

gix-worktree-stream/src/entry.rs

@@ -13,8 +13,10 @@ use crate::{protocol, Entry, Stream};
 pub enum Error {
     #[error(transparent)]
     Io(#[from] std::io::Error),
-    #[error("Could not find a blob or tree for archival")]
-    Find(#[source] Box<dyn std::error::Error + Send + Sync + 'static>),
+    #[error("Could not find a tree's leaf, typically a blob")]
+    Find(#[from] gix_object::find::existing::Error),
+    #[error("Could not find a tree to traverse")]
+    FindTree(#[from] gix_object::find::existing_iter::Error),
     #[error("Could not query attributes for path \"{path}\"")]
     Attributes {
         path: BString,

gix-worktree-stream/src/from_tree/mod.rs

@@ -1,10 +1,11 @@
 use std::io::Write;
 
 use gix_object::bstr::BStr;
+use gix_object::FindExt;
 
 use crate::{entry, entry::Error, protocol, AdditionalEntry, SharedErrorSlot, Stream};
 
-/// Use `find` to traverse `tree` and fetch the contained blobs to return as [`Stream`], which makes them queryable
+/// Use `objects` to traverse `tree` and fetch the contained blobs to return as [`Stream`], which makes them queryable
 /// on demand with support for streaming each entry.
 ///
 /// `pipeline` is used to convert blobs to their worktree representation, and `attributes` is used to read
@@ -32,26 +33,25 @@ use crate::{entry, entry::Error, protocol, AdditionalEntry, SharedErrorSlot, Str
 /// ### Limitations
 ///
 /// * `export-subst` is not support, as it requires the entire formatting engine of `git log`.
-pub fn from_tree<Find, E1, E2>(
+pub fn from_tree<Find, E>(
     tree: gix_hash::ObjectId,
-    find: Find,
+    objects: Find,
     pipeline: gix_filter::Pipeline,
-    attributes: impl FnMut(&BStr, gix_object::tree::EntryMode, &mut gix_attributes::search::Outcome) -> Result<(), E2>
+    attributes: impl FnMut(&BStr, gix_object::tree::EntryMode, &mut gix_attributes::search::Outcome) -> Result<(), E>
         + Send
         + 'static,
 ) -> Stream
 where
-    Find: for<'a> FnMut(&gix_hash::oid, &'a mut Vec<u8>) -> Result<gix_object::Data<'a>, E1> + Clone + Send + 'static,
-    E1: std::error::Error + Send + Sync + 'static,
-    E2: std::error::Error + Send + Sync + 'static,
+    Find: gix_object::Find + Clone + Send + 'static,
+    E: std::error::Error + Send + Sync + 'static,
 {
     let (stream, mut write, additional_entries) = Stream::new();
     std::thread::spawn({
         let slot = stream.err.clone();
         move || {
             if let Err(err) = run(
                 tree,
-                find,
+                objects,
                 pipeline,
                 attributes,
                 &mut write,
@@ -76,28 +76,26 @@ where
     stream
 }
 
-fn run<Find, E1, E2>(
+fn run<Find, E>(
     tree: gix_hash::ObjectId,
-    mut find: Find,
+    objects: Find,
     mut pipeline: gix_filter::Pipeline,
-    mut attributes: impl FnMut(&BStr, gix_object::tree::EntryMode, &mut gix_attributes::search::Outcome) -> Result<(), E2>
+    mut attributes: impl FnMut(&BStr, gix_object::tree::EntryMode, &mut gix_attributes::search::Outcome) -> Result<(), E>
         + Send
         + 'static,
     out: &mut gix_features::io::pipe::Writer,
     err: SharedErrorSlot,
     additional_entries: std::sync::mpsc::Receiver<AdditionalEntry>,
 ) -> Result<(), Error>
 where
-    Find: for<'a> FnMut(&gix_hash::oid, &'a mut Vec<u8>) -> Result<gix_object::Data<'a>, E1> + Clone + Send + 'static,
-    E1: std::error::Error + Send + Sync + 'static,
-    E2: std::error::Error + Send + Sync + 'static,
+    Find: gix_object::Find + Clone,
+    E: std::error::Error + Send + Sync + 'static,
 {
     let mut buf = Vec::new();
-    let obj = find(tree.as_ref(), &mut buf).map_err(|err| Error::Find(Box::new(err)))?;
+    let tree_iter = objects.find_tree_iter(tree.as_ref(), &mut buf)?;
     if pipeline.driver_context_mut().treeish.is_none() {
         pipeline.driver_context_mut().treeish = Some(tree);
     }
-    let tree = gix_object::TreeRefIter::from_bytes(obj.data);
 
     let mut attrs = gix_attributes::search::Outcome::default();
     attrs.initialize_with_selection(&Default::default(), Some("export-ignore"));
@@ -106,10 +104,7 @@ where
         err,
         pipeline,
         attrs,
-        find: {
-            let mut find = find.clone();
-            move |a: &gix_hash::oid, b: &mut Vec<u8>| find(a, b).map_err(|err| Error::Find(Box::new(err)))
-        },
+        objects: objects.clone(),
         fetch_attributes: move |a: &BStr, b: gix_object::tree::EntryMode, c: &mut gix_attributes::search::Outcome| {
             attributes(a, b, c).map_err(|err| Error::Attributes {
                 source: Box::new(err),
@@ -121,13 +116,9 @@ where
         buf: Vec::with_capacity(1024),
     };
     gix_traverse::tree::breadthfirst(
-        tree,
+        tree_iter,
         gix_traverse::tree::breadthfirst::State::default(),
-        |id, buf| {
-            find(id, buf)
-                .map(|obj| gix_object::TreeRefIter::from_bytes(obj.data))
-                .ok()
-        },
+        &objects,
         &mut dlg,
     )?;
 

gix-worktree-stream/src/from_tree/traverse.rs

@@ -3,15 +3,15 @@ use std::{collections::VecDeque, io::Write};
 use gix_filter::{driver::apply::MaybeDelayed, pipeline::convert::ToWorktreeOutcome};
 use gix_object::{
     bstr::{BStr, BString, ByteSlice, ByteVec},
-    tree,
+    tree, FindExt,
 };
 use gix_traverse::tree::{visit::Action, Visit};
 
 use crate::{entry::Error, protocol, SharedErrorSlot};
 
-pub struct Delegate<'a, AttributesFn, FindFn>
+pub struct Delegate<'a, AttributesFn, Find>
 where
-    FindFn: for<'b> FnMut(&gix_hash::oid, &'b mut Vec<u8>) -> Result<gix_object::Data<'b>, Error> + 'static,
+    Find: gix_object::Find,
 {
     pub(crate) out: &'a mut gix_features::io::pipe::Writer,
     pub(crate) err: SharedErrorSlot,
@@ -20,13 +20,13 @@ where
     pub(crate) pipeline: gix_filter::Pipeline,
     pub(crate) attrs: gix_attributes::search::Outcome,
     pub(crate) fetch_attributes: AttributesFn,
-    pub(crate) find: FindFn,
+    pub(crate) objects: Find,
     pub(crate) buf: Vec<u8>,
 }
 
-impl<AttributesFn, FindFn> Delegate<'_, AttributesFn, FindFn>
+impl<AttributesFn, Find> Delegate<'_, AttributesFn, Find>
 where
-    FindFn: for<'b> FnMut(&gix_hash::oid, &'b mut Vec<u8>) -> Result<gix_object::Data<'b>, Error> + 'static,
+    Find: gix_object::Find,
     AttributesFn:
         FnMut(&BStr, gix_object::tree::EntryMode, &mut gix_attributes::search::Outcome) -> Result<(), Error> + 'static,
 {
@@ -62,7 +62,7 @@ where
         if self.ignore_state().is_set() {
             return Ok(Action::Continue);
         }
-        (self.find)(entry.oid, &mut self.buf)?;
+        self.objects.find(entry.oid, &mut self.buf)?;
 
         self.pipeline.driver_context_mut().blob = Some(entry.oid.into());
         let converted = self.pipeline.convert_to_worktree(
@@ -99,9 +99,9 @@ where
     }
 }
 
-impl<AttributesFn, FindFn> Visit for Delegate<'_, AttributesFn, FindFn>
+impl<AttributesFn, Find> Visit for Delegate<'_, AttributesFn, Find>
 where
-    FindFn: for<'a> FnMut(&gix_hash::oid, &'a mut Vec<u8>) -> Result<gix_object::Data<'a>, Error> + 'static,
+    Find: gix_object::Find,
     AttributesFn:
         FnMut(&BStr, gix_object::tree::EntryMode, &mut gix_attributes::search::Outcome) -> Result<(), Error> + 'static,
 {

gix-worktree-stream/tests/stream.rs

@@ -12,34 +12,45 @@ mod from_tree {
     };
 
     use gix_attributes::glob::pattern::Case;
-    use gix_object::FindExt;
+    use gix_hash::oid;
     use gix_object::{bstr::ByteSlice, tree::EntryMode};
+    use gix_object::{Data, FindExt};
     use gix_testtools::once_cell::sync::Lazy;
     use gix_worktree::stack::state::attributes::Source;
 
     use crate::hex_to_id;
 
+    #[derive(Clone)]
+    struct FailObjectRetrieval;
+
+    impl gix_object::Find for FailObjectRetrieval {
+        fn try_find<'a>(
+            &self,
+            _id: &oid,
+            _buffer: &'a mut Vec<u8>,
+        ) -> Result<Option<Data<'a>>, gix_object::find::Error> {
+            Err(Box::new(Error::new(ErrorKind::Other, "object retrieval failed")))
+        }
+    }
+
     #[test]
     fn can_receive_err_if_root_is_not_found() {
         let mut stream = gix_worktree_stream::from_tree(
             gix_hash::Kind::Sha1.null(),
-            |_, _| Err(Error::new(ErrorKind::Other, "object retrieval failed")),
+            FailObjectRetrieval,
             mutating_pipeline(false),
             |_, _, _| -> Result<_, Infallible> { unreachable!("must not be called") },
         );
         let err = stream.next_entry().unwrap_err();
-        assert_eq!(err.to_string(), "Could not find a blob or tree for archival");
+        assert_eq!(err.to_string(), "Could not find a tree to traverse");
     }
 
     #[test]
     fn can_receive_err_if_attribute_not_found() -> gix_testtools::Result {
         let (_dir, head_tree, odb, _cache) = basic()?;
-        let mut stream = gix_worktree_stream::from_tree(
-            head_tree,
-            move |id, buf| odb.find(id, buf),
-            mutating_pipeline(false),
-            |_, _, _| Err(Error::new(ErrorKind::Other, "attribute retrieval failed")),
-        );
+        let mut stream = gix_worktree_stream::from_tree(head_tree, odb, mutating_pipeline(false), |_, _, _| {
+            Err(Error::new(ErrorKind::Other, "attribute retrieval failed"))
+        });
         let err = stream.next_entry().unwrap_err();
         assert_eq!(
             err.to_string(),
@@ -53,10 +64,7 @@ mod from_tree {
         let (dir, head_tree, odb, mut cache) = basic()?;
         let mut stream = gix_worktree_stream::from_tree(
             head_tree,
-            {
-                let odb = odb.clone();
-                move |id, buf| odb.find(id, buf)
-            },
+            odb.clone(),
             mutating_pipeline(true),
             move |rela_path, mode, attrs| {
                 cache
@@ -214,10 +222,7 @@ mod from_tree {
         let (_dir, head_tree, odb, mut cache) = basic()?;
         let mut stream = gix_worktree_stream::from_tree(
             head_tree,
-            {
-                let odb = odb.clone();
-                move |id, buf| odb.find(id, buf)
-            },
+            odb.clone(),
             mutating_pipeline(false),
             move |rela_path, mode, attrs| {
                 cache

gix-worktree/src/stack/delegate.rs

@@ -18,19 +18,13 @@ pub struct Statistics {
     pub pop_directory: usize,
 }
 
-pub(crate) type FindFn<'a> = dyn for<'b> FnMut(
-        &gix_hash::oid,
-        &'b mut Vec<u8>,
-    ) -> Result<gix_object::BlobRef<'b>, Box<dyn std::error::Error + Send + Sync>>
-    + 'a;
-
 pub(crate) struct StackDelegate<'a, 'find> {
     pub state: &'a mut State,
     pub buf: &'a mut Vec<u8>,
     #[cfg_attr(not(feature = "attributes"), allow(dead_code))]
     pub is_dir: bool,
     pub id_mappings: &'a Vec<PathIdMapping>,
-    pub find: &'find mut FindFn<'find>,
+    pub objects: &'find dyn gix_object::Find,
     pub case: gix_glob::pattern::Case,
     pub statistics: &'a mut super::Statistics,
 }
@@ -63,7 +57,7 @@ impl<'a, 'find> gix_fs::stack::Delegate for StackDelegate<'a, 'find> {
                     rela_dir,
                     self.buf,
                     self.id_mappings,
-                    self.find,
+                    self.objects,
                     &mut self.statistics.attributes,
                 )?;
             }
@@ -75,7 +69,7 @@ impl<'a, 'find> gix_fs::stack::Delegate for StackDelegate<'a, 'find> {
                     rela_dir,
                     self.buf,
                     self.id_mappings,
-                    &mut self.find,
+                    self.objects,
                     &mut self.statistics.attributes,
                 )?;
                 ignore.push_directory(
@@ -84,7 +78,7 @@ impl<'a, 'find> gix_fs::stack::Delegate for StackDelegate<'a, 'find> {
                     rela_dir,
                     self.buf,
                     self.id_mappings,
-                    &mut self.find,
+                    self.objects,
                     self.case,
                     &mut self.statistics.ignore,
                 )?
@@ -95,7 +89,7 @@ impl<'a, 'find> gix_fs::stack::Delegate for StackDelegate<'a, 'find> {
                 rela_dir,
                 self.buf,
                 self.id_mappings,
-                &mut self.find,
+                self.objects,
                 self.case,
                 &mut self.statistics.ignore,
             )?,

gix-worktree/src/stack/mod.rs

@@ -2,7 +2,6 @@
 use std::path::{Path, PathBuf};
 
 use bstr::{BStr, ByteSlice};
-use gix_hash::oid;
 
 use super::Stack;
 use crate::PathIdMapping;
@@ -106,26 +105,25 @@ impl Stack {
     /// symlinks are in that path.
     /// Unless `is_dir` is known with `Some(…)`, then `relative` points to a directory itself in which case the entire resulting
     /// path is created as directory. If it's not known it is assumed to be a file.
-    /// `find` maybe used to lookup objects from an [id mapping][crate::stack::State::id_mappings_from_index()], with mappnigs
+    /// `objects` maybe used to lookup objects from an [id mapping][crate::stack::State::id_mappings_from_index()], with mappnigs
     ///
     /// Provide access to cached information for that `relative` path via the returned platform.
-    pub fn at_path<Find, E>(
+    pub fn at_path<Find>(
         &mut self,
         relative: impl AsRef<Path>,
         is_dir: Option<bool>,
-        mut find: Find,
+        objects: Find,
     ) -> std::io::Result<Platform<'_>>
     where
-        Find: for<'a> FnMut(&oid, &'a mut Vec<u8>) -> Result<gix_object::BlobRef<'a>, E>,
-        E: std::error::Error + Send + Sync + 'static,
+        Find: gix_object::Find,
     {
         self.statistics.platforms += 1;
         let mut delegate = StackDelegate {
             state: &mut self.state,
             buf: &mut self.buf,
             is_dir: is_dir.unwrap_or(false),
             id_mappings: &self.id_mappings,
-            find: &mut |oid, buf| Ok(find(oid, buf).map_err(Box::new)?),
+            objects: &objects,
             case: self.case,
             statistics: &mut self.statistics,
         };
@@ -136,31 +134,30 @@ impl Stack {
 
     /// Obtain a platform for lookups from a repo-`relative` path, typically obtained from an index entry. `is_dir` should reflect
     /// whether it's a directory or not, or left at `None` if unknown.
-    /// `find` maybe used to lookup objects from an [id mapping][crate::stack::State::id_mappings_from_index()].
+    /// `objects` maybe used to lookup objects from an [id mapping][crate::stack::State::id_mappings_from_index()].
     /// All effects are similar to [`at_path()`][Self::at_path()].
     ///
     /// If `relative` ends with `/` and `is_dir` is `None`, it is automatically assumed to be a directory.
     ///
     /// ### Panics
     ///
     /// on illformed UTF8 in `relative`
-    pub fn at_entry<'r, Find, E>(
+    pub fn at_entry<'r, Find>(
         &mut self,
         relative: impl Into<&'r BStr>,
         is_dir: Option<bool>,
-        find: Find,
+        objects: Find,
     ) -> std::io::Result<Platform<'_>>
     where
-        Find: for<'a> FnMut(&oid, &'a mut Vec<u8>) -> Result<gix_object::BlobRef<'a>, E>,
-        E: std::error::Error + Send + Sync + 'static,
+        Find: gix_object::Find,
     {
         let relative = relative.into();
         let relative_path = gix_path::from_bstr(relative);
 
         self.at_path(
             relative_path,
             is_dir.or_else(|| relative.ends_with_str("/").then_some(true)),
-            find,
+            objects,
         )
     }
 }