diff --git a/cli/src/diff_util.rs b/cli/src/diff_util.rs
index 4c2d81fdbb..b52cde1c4a 100644
--- a/cli/src/diff_util.rs
+++ b/cli/src/diff_util.rs
@@ -22,7 +22,9 @@ use futures::StreamExt;
 use itertools::Itertools;
 use jj_lib::backend::{BackendError, CopyRecords, TreeValue};
 use jj_lib::commit::Commit;
-use jj_lib::conflicts::{materialized_diff_stream, MaterializedTreeValue};
+use jj_lib::conflicts::{
+    materialized_diff_stream, MaterializedTreeDiffEntry, MaterializedTreeValue,
+};
 use jj_lib::diff::{Diff, DiffHunk};
 use jj_lib::files::DiffLine;
 use jj_lib::matchers::Matcher;
@@ -567,7 +569,12 @@ pub fn show_color_words_diff(
 ) -> Result<(), DiffRenderError> {
     let mut diff_stream = materialized_diff_stream(store, tree_diff);
     async {
-        while let Some((path, diff)) = diff_stream.next().await {
+        while let Some(MaterializedTreeDiffEntry {
+            source: _, // TODO handle copy tracking
+            target: path,
+            value: diff,
+        }) = diff_stream.next().await
+        {
             let ui_path = path_converter.format_file_path(&path);
             let (left_value, right_value) = diff?;
 
@@ -714,7 +721,12 @@ pub fn show_file_by_file_diff(
     let right_wc_dir = temp_dir.path().join("right");
     let mut diff_stream = materialized_diff_stream(store, tree_diff);
     async {
-        while let Some((path, diff)) = diff_stream.next().await {
+        while let Some(MaterializedTreeDiffEntry {
+            source: _, // TODO handle copy tracking
+            target: path,
+            value: diff,
+        }) = diff_stream.next().await
+        {
             let ui_path = path_converter.format_file_path(&path);
             let (left_value, right_value) = diff?;
 
@@ -1032,10 +1044,15 @@ pub fn show_git_diff(
 ) -> Result<(), DiffRenderError> {
     let mut diff_stream = materialized_diff_stream(store, tree_diff);
     async {
-        while let Some((path, diff)) = diff_stream.next().await {
+        while let Some(MaterializedTreeDiffEntry {
+            source: _, // TODO handle copy tracking
+            target: path,
+            value: diff,
+        }) = diff_stream.next().await
+        {
             let path_string = path.as_internal_file_string();
             let (left_value, right_value) = diff?;
-            let left_part = git_diff_part(&path, left_value)?;
+            let left_part = git_digf_part(&path, left_value)?;
             let right_part = git_diff_part(&path, right_value)?;
             formatter.with_label("file_header", |formatter| {
                 writeln!(formatter, "diff --git a/{path_string} b/{path_string}")?;
@@ -1179,7 +1196,12 @@ pub fn show_diff_stat(
 
     let mut diff_stream = materialized_diff_stream(store, tree_diff);
     async {
-        while let Some((repo_path, diff)) = diff_stream.next().await {
+        while let Some(MaterializedTreeDiffEntry {
+            source: _, // TODO handle copy tracking
+            target: repo_path,
+            value: diff,
+        }) = diff_stream.next().await
+        {
             let (left, right) = diff?;
             let path = path_converter.format_file_path(&repo_path);
             let left_content = diff_content(&repo_path, left)?;
diff --git a/lib/src/conflicts.rs b/lib/src/conflicts.rs
index 44484daf6b..9cb50d6789 100644
--- a/lib/src/conflicts.rs
+++ b/lib/src/conflicts.rs
@@ -325,29 +325,38 @@ fn diff_size(hunks: &[DiffHunk]) -> usize {
         .sum()
 }
 
+pub struct MaterializedTreeDiffEntry {
+    pub source: RepoPathBuf,
+    pub target: RepoPathBuf,
+    pub value: BackendResult<(MaterializedTreeValue, MaterializedTreeValue)>,
+}
+
 pub fn materialized_diff_stream<'a>(
     store: &'a Store,
     tree_diff: TreeDiffStream<'a>,
-) -> impl Stream<
-    Item = (
-        RepoPathBuf,
-        BackendResult<(MaterializedTreeValue, MaterializedTreeValue)>,
-    ),
-> + 'a {
+) -> impl Stream<Item = MaterializedTreeDiffEntry> + 'a {
     tree_diff
         .map(
             |TreeDiffEntry {
-                 source: _, // TODO handle copy tracking
-                 target: path,
-                 value: diff,
+                 source,
+                 target,
+                 value,
              }| async {
-                match diff {
-                    Err(err) => (path, Err(err)),
+                match value {
+                    Err(err) => MaterializedTreeDiffEntry {
+                        source,
+                        target,
+                        value: Err(err),
+                    },
                     Ok((before, after)) => {
-                        let before_future = materialize_tree_value(store, &path, before);
-                        let after_future = materialize_tree_value(store, &path, after);
+                        let before_future = materialize_tree_value(store, &source, before);
+                        let after_future = materialize_tree_value(store, &target, after);
                         let values = try_join!(before_future, after_future);
-                        (path, values)
+                        MaterializedTreeDiffEntry {
+                            source,
+                            target,
+                            value: values,
+                        }
                     }
                 }
             },
diff --git a/lib/src/default_index/revset_engine.rs b/lib/src/default_index/revset_engine.rs
index cc1bbc4161..6eebdc0e2e 100644
--- a/lib/src/default_index/revset_engine.rs
+++ b/lib/src/default_index/revset_engine.rs
@@ -30,7 +30,9 @@ use super::rev_walk::{EagerRevWalk, PeekableRevWalk, RevWalk, RevWalkBuilder};
 use super::revset_graph_iterator::RevsetGraphWalk;
 use crate::backend::{BackendError, BackendResult, ChangeId, CommitId, MillisSinceEpoch};
 use crate::commit::Commit;
-use crate::conflicts::{materialized_diff_stream, MaterializedTreeValue};
+use crate::conflicts::{
+    materialized_diff_stream, MaterializedTreeDiffEntry, MaterializedTreeValue,
+};
 use crate::default_index::{AsCompositeIndex, CompositeIndex, IndexPosition};
 use crate::graph::GraphEdge;
 use crate::matchers::{Matcher, Visit};
@@ -1175,7 +1177,12 @@ fn matches_diff_from_parent(
     // pairs can be compared one by one. #4062
     let mut diff_stream = materialized_diff_stream(store, tree_diff);
     async {
-        while let Some((path, diff)) = diff_stream.next().await {
+        while let Some(MaterializedTreeDiffEntry {
+            source: _, // TODO handle copy tracking
+            target: path,
+            value: diff,
+        }) = diff_stream.next().await
+        {
             let (left_value, right_value) = diff?;
             let left_content = to_file_content(&path, left_value)?;
             let right_content = to_file_content(&path, right_value)?;