Fix startup message and cache file creation (#4705)

* only show startup loading message if we've been loading for more than 400ms

* create relevant cache folders before attempting to write startup cache files

* fix flaky tests

* rustfmt

* add pr

8 files changed, 85 insertions, 20 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index fb9ac53f..567a2b15 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -49,6 +49,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 * feat: allow querying tab info (id, name and position) from the CLI as well as general info about all tabs (https://github.com/zellij-org/zellij/pull/4695)
 * feat: propagate plugin configuration changes to plugins (https://github.com/zellij-org/zellij/pull/4698)
 * feat: allow plugins to query env vars set upon session creation (gated behind a relevant permission) (https://github.com/zellij-org/zellij/pull/4700)
+* fix: make sure cache folders exist in all startup paths (https://github.com/zellij-org/zellij/pull/4705)
 
 
 ## [0.43.1] - 2025-08-08
diff --git a/zellij-client/src/lib.rs b/zellij-client/src/lib.rs
index b5224eb4..4061b690 100644
--- a/zellij-client/src/lib.rs
+++ b/zellij-client/src/lib.rs
@@ -83,7 +83,7 @@ use crate::{
 use termwiz::input::InputEvent;
 use zellij_utils::cli::CliArgs;
 use zellij_utils::{
-    channels::{self, ChannelWithContext, SenderWithContext},
+    channels::{self, ChannelWithContext, RecvTimeoutError, SenderWithContext},
     consts::{set_permissions, ZELLIJ_SOCK_DIR},
     data::{ClientId, ConnectToSession, KeyWithModifier, LayoutInfo, LayoutMetadata},
     envs,
@@ -947,6 +947,9 @@ pub fn start_client(
 
     let mut exit_msg = String::new();
     let mut loading = true;
+    let mut showed_loading_message = false;
+    let loading_start = std::time::Instant::now();
+    let loading_delay = std::time::Duration::from_millis(400);
     let mut pending_instructions = vec![];
     let mut synchronised_output = match os_input.env_variable("TERM").as_deref() {
         Some("alacritty") => Some(SyncOutput::DCS),
@@ -954,16 +957,34 @@ pub fn start_client(
     };
 
     let mut stdout = os_input.get_stdout_writer();
-    stdout
-        .write_all("\u{1b}[1m\u{1b}[HLoading Zellij\u{1b}[m\n\r".as_bytes())
-        .expect("cannot write to stdout");
-    stdout.flush().expect("could not flush");
 
     loop {
         let (client_instruction, mut err_ctx) = if !loading && !pending_instructions.is_empty() {
             // there are buffered instructions, we need to go through them before processing the
             // new ones
             pending_instructions.remove(0)
+        } else if loading && !showed_loading_message {
+            let remaining = loading_delay
+                .checked_sub(loading_start.elapsed())
+                .unwrap_or(std::time::Duration::ZERO);
+            match receive_client_instructions.recv_timeout(remaining) {
+                Ok(instruction) => instruction,
+                Err(RecvTimeoutError::Timeout) => {
+                    // 400ms elapsed with no completion — show loading UI
+                    stdout
+                        .write_all("\u{1b}[1m\u{1b}[HLoading Zellij\u{1b}[m\n\r".as_bytes())
+                        .expect("cannot write to stdout");
+                    stdout.flush().expect("could not flush");
+                    showed_loading_message = true;
+                    // Now block normally
+                    receive_client_instructions
+                        .recv()
+                        .expect("failed to receive app instruction on channel")
+                },
+                Err(RecvTimeoutError::Disconnected) => {
+                    panic!("client instruction channel disconnected");
+                },
+            }
         } else {
             receive_client_instructions
                 .recv()
@@ -974,16 +995,20 @@ pub fn start_client(
             // when the app is still loading, we buffer instructions and show a loading screen
             match client_instruction {
                 ClientInstruction::StartedParsingStdinQuery => {
-                    stdout
-                        .write_all("Querying terminal emulator for \u{1b}[32;1mdefault colors\u{1b}[m and \u{1b}[32;1mpixel/cell\u{1b}[m ratio...".as_bytes())
-                        .expect("cannot write to stdout");
-                    stdout.flush().expect("could not flush");
+                    if showed_loading_message {
+                        stdout
+                            .write_all("Querying terminal emulator for \u{1b}[32;1mdefault colors\u{1b}[m and \u{1b}[32;1mpixel/cell\u{1b}[m ratio...".as_bytes())
+                            .expect("cannot write to stdout");
+                        stdout.flush().expect("could not flush");
+                    }
                 },
                 ClientInstruction::DoneParsingStdinQuery => {
-                    stdout
-                        .write_all("done".as_bytes())
-                        .expect("cannot write to stdout");
-                    stdout.flush().expect("could not flush");
+                    if showed_loading_message {
+                        stdout
+                            .write_all("done".as_bytes())
+                            .expect("cannot write to stdout");
+                        stdout.flush().expect("could not flush");
+                    }
                     loading = false;
                 },
                 instruction => {
diff --git a/zellij-client/src/stdin_ansi_parser.rs b/zellij-client/src/stdin_ansi_parser.rs
index 7fa3492e..310360e3 100644
--- a/zellij-client/src/stdin_ansi_parser.rs
+++ b/zellij-client/src/stdin_ansi_parser.rs
@@ -129,6 +129,9 @@ impl StdinAnsiParser {
     }
     pub fn write_cache(&self, events: Vec<AnsiStdinInstruction>) {
         if let Ok(serialized_events) = serde_json::to_string(&events) {
+            if let Some(parent) = ZELLIJ_STDIN_CACHE_FILE.parent() {
+                let _ = std::fs::create_dir_all(parent);
+            }
             if let Ok(mut file) = File::create(ZELLIJ_STDIN_CACHE_FILE.as_path()) {
                 let _ = file.write_all(serialized_events.as_bytes());
             }
diff --git a/zellij-server/src/lib.rs b/zellij-server/src/lib.rs
index e24aa38e..38628129 100644
--- a/zellij-server/src/lib.rs
+++ b/zellij-server/src/lib.rs
@@ -2012,6 +2012,9 @@ fn should_show_release_notes(
     if ZELLIJ_SEEN_RELEASE_NOTES_CACHE_FILE.exists() {
         return false;
     } else {
+        if let Some(parent) = ZELLIJ_SEEN_RELEASE_NOTES_CACHE_FILE.parent() {
+            let _ = std::fs::create_dir_all(parent);
+        }
         if let Err(e) = std::fs::write(&*ZELLIJ_SEEN_RELEASE_NOTES_CACHE_FILE, &[]) {
             log::error!(
                 "Failed to write seen release notes indication to disk: {}",
diff --git a/zellij-server/src/unit/screen_tests.rs b/zellij-server/src/unit/screen_tests.rs
index 059235a1..96dd25aa 100644
--- a/zellij-server/src/unit/screen_tests.rs
+++ b/zellij-server/src/unit/screen_tests.rs
@@ -2196,7 +2196,16 @@ pub fn send_cli_send_keys_action_to_screen() {
     send_cli_action_to_server(&session_metadata, cli_action, client_id);
     std::thread::sleep(std::time::Duration::from_millis(100));
     mock_screen.teardown(vec![pty_writer_thread, screen_thread]);
-    assert_snapshot!(format!("{:?}", *received_pty_instructions.lock().unwrap()));
+    let received_write_instructions: Vec<_> = received_pty_instructions
+        .lock()
+        .unwrap()
+        .clone()
+        .into_iter()
+        .filter(|i| matches!(i, PtyWriteInstruction::Write(..)))
+        .collect();
+    // here we assert only the write instructions to make sure they arrived properly and in
+    // sequence to the pane
+    assert_snapshot!(format!("{:#?}", received_write_instructions));
 }
 
 #[test]
@@ -2965,7 +2974,15 @@ pub fn send_cli_toggle_active_tab_sync_action() {
     send_cli_action_to_server(&session_metadata, cli_write_action, client_id);
     std::thread::sleep(std::time::Duration::from_millis(100)); // give time for actions to be
     mock_screen.teardown(vec![pty_writer_thread, screen_thread]);
-    assert_snapshot!(format!("{:?}", *received_pty_instructions.lock().unwrap()));
+    let received_write_instructions: Vec<_> = received_pty_instructions
+        .lock()
+        .unwrap()
+        .clone()
+        .into_iter()
+        .filter(|i| matches!(i, PtyWriteInstruction::Write(..)))
+        .collect();
+    // here we should have 2 Write instructions, one for each pane
+    assert_snapshot!(format!("{:?}", received_write_instructions));
 }
 
 #[test]
diff --git a/zellij-server/src/unit/snapshots/zellij_server__screen__screen_tests__send_cli_send_keys_action_to_screen.snap b/zellij-server/src/unit/snapshots/zellij_server__screen__screen_tests__send_cli_send_keys_action_to_screen.snap
index 75e4aeef..c2acd715 100644
--- a/zellij-server/src/unit/snapshots/zellij_server__screen__screen_tests__send_cli_send_keys_action_to_screen.snap
+++ b/zellij-server/src/unit/snapshots/zellij_server__screen__screen_tests__send_cli_send_keys_action_to_screen.snap
@@ -1,5 +1,20 @@
 ---
 source: zellij-server/src/./unit/screen_tests.rs
-expression: "format!(\"{:?}\", *received_pty_instructions.lock().unwrap())"
+expression: "format!(\"{:#?}\", received_write_instructions)"
 ---
-[StartCachingResizes, ApplyCachedResizes, StartCachingResizes, ResizePty(0, 119, 18, None, None), ResizePty(0, 119, 18, None, None), ResizePty(0, 119, 18, None, None), ResizePty(0, 119, 18, None, None), ApplyCachedResizes, ResizePty(0, 119, 18, None, None), ResizePty(0, 119, 18, None, None), ResizePty(0, 119, 18, None, None), ResizePty(0, 119, 18, None, None), ResizePty(0, 119, 18, None, None), ApplyCachedResizes, ApplyCachedResizes, ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, Write([1], 0, None), ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, Write([120], 0, None), ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, Exit]
+[
+    Write(
+        [
+            1,
+        ],
+        0,
+        None,
+    ),
+    Write(
+        [
+            120,
+        ],
+        0,
+        None,
+    ),
+]
diff --git a/zellij-server/src/unit/snapshots/zellij_server__screen__screen_tests__send_cli_toggle_active_tab_sync_action.snap b/zellij-server/src/unit/snapshots/zellij_server__screen__screen_tests__send_cli_toggle_active_tab_sync_action.snap
index d9fe6929..69157166 100644
--- a/zellij-server/src/unit/snapshots/zellij_server__screen__screen_tests__send_cli_toggle_active_tab_sync_action.snap
+++ b/zellij-server/src/unit/snapshots/zellij_server__screen__screen_tests__send_cli_toggle_active_tab_sync_action.snap
@@ -1,5 +1,5 @@
 ---
 source: zellij-server/src/./unit/screen_tests.rs
-expression: "format!(\"{:?}\", *received_pty_instructions.lock().unwrap())"
+expression: "format!(\"{:?}\", received_write_instructions)"
 ---
-[StartCachingResizes, ApplyCachedResizes, StartCachingResizes, ResizePty(0, 59, 18, None, None), ResizePty(1, 58, 18, None, None), ResizePty(0, 59, 18, None, None), ResizePty(1, 58, 18, None, None), ResizePty(0, 59, 18, None, None), ResizePty(1, 58, 18, None, None), ResizePty(0, 59, 18, None, None), ResizePty(1, 58, 18, None, None), ApplyCachedResizes, ResizePty(0, 58, 18, None, None), ResizePty(1, 59, 18, None, None), ResizePty(0, 58, 18, None, None), ResizePty(1, 59, 18, None, None), ResizePty(0, 58, 18, None, None), ResizePty(1, 59, 18, None, None), ResizePty(0, 58, 18, None, None), ResizePty(1, 59, 18, None, None), ResizePty(0, 59, 18, None, None), ResizePty(1, 58, 18, None, None), ApplyCachedResizes, ApplyCachedResizes, ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, Write([102, 111, 111], 0, None), Write([102, 111, 111], 1, None), ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, StartCachingResizes, ApplyCachedResizes, Exit]
+[Write([102, 111, 111], 0, None), Write([102, 111, 111], 1, None)]
diff --git a/zellij-utils/src/channels.rs b/zellij-utils/src/channels.rs
index 4fdbc8bc..18506329 100644
--- a/zellij-utils/src/channels.rs
+++ b/zellij-utils/src/channels.rs
@@ -5,7 +5,8 @@ use std::cell::RefCell;
 
 use crate::errors::{get_current_ctx, ErrorContext};
 pub use crossbeam::channel::{
-    bounded, unbounded, Receiver, RecvError, Select, SendError, Sender, TrySendError,
+    bounded, unbounded, Receiver, RecvError, RecvTimeoutError, Select, SendError, Sender,
+    TrySendError,
 };
 
 /// An [MPSC](mpsc) asynchronous channel with added error context.