improve files in diff speed (#976)

Author: Stephan Dilly

Diff for: asyncgit/src/sync/commit_files.rs

@@ -4,7 +4,7 @@ use super::{stash::is_stash_commit, utils::repo, CommitId};
 use crate::{
 	error::Error, error::Result, StatusItem, StatusItemType,
 };
-use git2::{Diff, DiffDelta, DiffOptions, Repository};
+use git2::{Diff, DiffOptions, Repository};
 use scopetime::scope_time;
 
 /// get all files that are part of a commit
@@ -23,24 +23,30 @@ pub fn get_commit_files(
 		get_commit_diff(&repo, id, None)?
 	};
 
-	let mut res = Vec::new();
+	let deltas = {
+		scope_time!("get_commit_files.delta-count");
+		diff.deltas().count()
+	};
+
+	log::debug!("deltas in diff: {}", deltas);
+
+	let mut res = Vec::with_capacity(deltas);
+
+	{
+		scope_time!("get_commit_files.diff-foreach");
+		for delta in diff.deltas() {
+			let status = StatusItemType::from(delta.status());
 
-	diff.foreach(
-		&mut |delta: DiffDelta<'_>, _progress| {
 			res.push(StatusItem {
 				path: delta
 					.new_file()
 					.path()
 					.map(|p| p.to_str().unwrap_or("").to_string())
 					.unwrap_or_default(),
-				status: StatusItemType::from(delta.status()),
+				status,
 			});
-			true
-		},
-		None,
-		None,
-		None,
-	)?;
+		}
+	}
 
 	Ok(res)
 }
@@ -51,7 +57,7 @@ pub fn get_compare_commits_diff(
 	ids: (CommitId, CommitId),
 	pathspec: Option<String>,
 ) -> Result<Diff<'_>> {
-	// scope_time!("get_compare_commits_diff");
+	scope_time!("get_compare_commits_diff");
 
 	let commits = (
 		repo.find_commit(ids.0.into())?,
@@ -89,7 +95,7 @@ pub(crate) fn get_commit_diff(
 	id: CommitId,
 	pathspec: Option<String>,
 ) -> Result<Diff<'_>> {
-	// scope_time!("get_commit_diff");
+	scope_time!("get_commit_diff");
 
 	let commit = repo.find_commit(id.into())?;
 	let commit_tree = commit.tree()?;