From d9e716bc8e744042afc21e86a4497305320e3ea9 Mon Sep 17 00:00:00 2001
From: Christian Schilling <christian.schilling.de@gmail.com>
Date: Sun, 16 Nov 2025 21:13:41 +0100
Subject: [PATCH] Use "populate" instead of "transpose" for pin filter

We didn't realize that we can use those existing functions instead
of creating a new one.
Going via pathstree() and populate() might not be the absolute best possible
route, but those use memoization and should be much faster for repeated
application that the transpose() which always needs to look at all paths.
---
 josh-core/src/filter/mod.rs  | 10 ++++++----
 josh-core/src/filter/tree.rs | 38 +-----------------------------------
 2 files changed, 7 insertions(+), 41 deletions(-)

diff --git a/josh-core/src/filter/mod.rs b/josh-core/src/filter/mod.rs
index bb6e2bada..36bb6132b 100644
--- a/josh-core/src/filter/mod.rs
+++ b/josh-core/src/filter/mod.rs
@@ -1543,12 +1543,14 @@ fn per_rev_filter(
             )?;
 
             let parent = transaction.repo().find_commit(parent)?;
-            let parent = parent.tree()?;
 
-            let pin_subtract = pin_subtract.tree();
-            let pin_overlay = tree::transpose(transaction, pin_subtract, &parent)?;
+            let pin_overlay = tree::populate(
+                transaction,
+                tree::pathstree("", pin_subtract.tree.id(), transaction)?.id(),
+                parent.tree_id(),
+            )?;
 
-            Some((pin_subtract.id(), pin_overlay.id()))
+            Some((pin_subtract.tree.id(), pin_overlay))
         } else {
             None
         }
diff --git a/josh-core/src/filter/tree.rs b/josh-core/src/filter/tree.rs
index 49e7b1a8a..0fc1d8fd0 100644
--- a/josh-core/src/filter/tree.rs
+++ b/josh-core/src/filter/tree.rs
@@ -1,5 +1,4 @@
 use super::*;
-use std::path::PathBuf;
 
 use crate::cache::TransactionContext;
 use crate::cache_stack::CacheStack;
@@ -890,7 +889,7 @@ pub fn repopulated_tree(
     populate(transaction, ipaths.id(), partial_tree.id())
 }
 
-fn populate(
+pub fn populate(
     transaction: &cache::Transaction,
     paths: git2::Oid,
     content: git2::Oid,
@@ -1002,41 +1001,6 @@ pub fn get_blob(repo: &git2::Repository, tree: &git2::Tree, path: &Path) -> Stri
     content.to_owned()
 }
 
-/// Compose a new tree by taking paths out of `paths`,
-/// and actual blobs out of `blobs`.
-pub fn transpose<'a>(
-    transaction: &'a cache::Transaction,
-    paths: &'a git2::Tree,
-    blobs: &'a git2::Tree,
-) -> JoshResult<git2::Tree<'a>> {
-    use git2::build::TreeUpdateBuilder;
-    use git2::{TreeWalkMode, TreeWalkResult};
-
-    let mut builder = TreeUpdateBuilder::new();
-
-    paths.walk(TreeWalkMode::PostOrder, |path, entry| {
-        let path = PathBuf::from(path).join(entry.name().unwrap_or(""));
-
-        let entry = match blobs.get_path(&path) {
-            Ok(entry) => entry,
-            Err(e) if e.code() == git2::ErrorCode::NotFound => return TreeWalkResult::Ok,
-            Err(_) => return TreeWalkResult::Abort,
-        };
-
-        if entry.kind() != Some(git2::ObjectType::Blob) {
-            return TreeWalkResult::Ok;
-        }
-
-        builder.upsert(path, entry.id(), git2::FileMode::Blob);
-        TreeWalkResult::Ok
-    })?;
-
-    let repo = transaction.repo();
-    let tree = builder.create_updated(repo, &empty(repo))?;
-
-    Ok(repo.find_tree(tree)?)
-}
-
 pub fn empty_id() -> git2::Oid {
     git2::Oid::from_str("4b825dc642cb6eb9a060e54bf8d69288fbee4904").unwrap()
 }