From 3cd7f1c2a83cc1e097b042e6f5e3d5e7b700d222 Mon Sep 17 00:00:00 2001
From: "Andrew Phillips (aider)" <andrew.phillips2@canada.ca>
Date: Tue, 6 May 2025 11:02:33 -0300
Subject: [PATCH] feat: stream item contents directly into diff command without
 temp files

---
 src/main.rs | 37 +++++++++++++++++--------------------
 1 file changed, 17 insertions(+), 20 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 487c85a..a664d7b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -516,30 +516,27 @@ fn mode_diff(cmd: &mut Command, args: Args, ids: &mut Vec<i64>, tags: &mut Vec<S
 
             let compression_engine_b = compression::get_engine(compression_type_b).expect("Unable to get compression engine");
 
-            let (fd_a, path_a) = tempfile::NamedTempFile::new().unwrap();
-            let (fd_b, path_b) = tempfile::NamedTempFile::new().unwrap();
+            let (fd_a_read, fd_a_write) = nix::unistd::pipe().unwrap();
+            let (fd_b_read, fd_b_write) = nix::unistd::pipe().unwrap();
 
-            let mut stdout_a = io::stdout();
-            let mut stdout_b = io::stdout();
-
-            let mut stdout_a = stdout_a.duplicate().unwrap();
-            let mut stdout_b = stdout_b.duplicate().unwrap();
-
-            io::stdout().set_fd(fd_a.as_raw_fd()).unwrap();
-            compression_engine_a.cat(item_path_a.clone())?;
-            io::stdout().set_fd(stdout_a.as_raw_fd()).unwrap();
-
-            io::stdout().set_fd(fd_b.as_raw_fd()).unwrap();
-            compression_engine_b.cat(item_path_b.clone())?;
-            io::stdout().set_fd(stdout_b.as_raw_fd()).unwrap();
-
-            let output = std::process::Command::new("diff")
+            let mut child = std::process::Command::new("diff")
                 .arg("-u")
-                .arg(path_a)
-                .arg(path_b)
-                .output()
+                .arg(format!("/dev/fd/{}", fd_a_read))
+                .arg(format!("/dev/fd/{}", fd_b_read))
+                .stdin(std::process::Stdio::null())
+                .stdout(std::process::Stdio::piped())
+                .stderr(std::process::Stdio::piped())
+                .spawn()
                 .expect("Failed to execute diff command");
 
+            let mut stdout_a = unsafe { std::fs::File::from_raw_fd(fd_a_write) };
+            let mut stdout_b = unsafe { std::fs::File::from_raw_fd(fd_b_write) };
+
+            compression_engine_a.cat(item_path_a.clone())?;
+            compression_engine_b.cat(item_path_b.clone())?;
+
+            let output = child.wait_with_output().expect("Failed to wait on diff command");
+
             if output.status.success() {
                 println!("{}", String::from_utf8_lossy(&output.stdout));
             } else {