From 689d43047d5d175596412698430a17df4a06ce0e Mon Sep 17 00:00:00 2001
From: Conrad Irwin <conrad.irwin@gmail.com>
Date: Wed, 31 Jan 2024 11:46:03 -0700
Subject: [PATCH] Don't panic when collaborating with older Zed versions
 (#7162)

Older Zed versions may send a buffer id of 0, which is no-longer
supported. (as of #6993)

This doesn't fix that, but it does ensure that we don't panic in the
workspace by maintaining the invariant that from_proto_state returns
Some(Task) if the variant matches.

It also converts the panic to an error should something similar happen
again in the future.


Release Notes:

- N/A
---
 crates/editor/src/items.rs        | 16 +++++++---------
 crates/workspace/src/workspace.rs |  6 ++++--
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/crates/editor/src/items.rs b/crates/editor/src/items.rs
index f26c4361b7e32c681e1d2211bf27a160bac183b8..d9ea6385cb19121c061f6f073988057c989c2d27 100644
--- a/crates/editor/src/items.rs
+++ b/crates/editor/src/items.rs
@@ -73,18 +73,16 @@ impl FollowableItem for Editor {
             .iter()
             .map(|excerpt| excerpt.buffer_id)
             .collect::<HashSet<_>>();
-        let buffers = project
-            .update(cx, |project, cx| {
-                buffer_ids
-                    .iter()
-                    .map(|id| BufferId::new(*id).map(|id| project.open_buffer_by_id(id, cx)))
-                    .collect::<Result<Vec<_>>>()
-            })
-            .ok()?;
+        let buffers = project.update(cx, |project, cx| {
+            buffer_ids
+                .iter()
+                .map(|id| BufferId::new(*id).map(|id| project.open_buffer_by_id(id, cx)))
+                .collect::<Result<Vec<_>>>()
+        });
 
         let pane = pane.downgrade();
         Some(cx.spawn(|mut cx| async move {
-            let mut buffers = futures::future::try_join_all(buffers)
+            let mut buffers = futures::future::try_join_all(buffers?)
                 .await
                 .debug_assert_ok("leaders don't share views for unshared buffers")?;
             let editor = pane.update(&mut cx, |pane, cx| {
diff --git a/crates/workspace/src/workspace.rs b/crates/workspace/src/workspace.rs
index 093393944b06796f699e8d9ef7fbaf579151c51c..177d7384b60f661c3bfd9a6e98ed7f3caa6500f1 100644
--- a/crates/workspace/src/workspace.rs
+++ b/crates/workspace/src/workspace.rs
@@ -2784,8 +2784,10 @@ impl Workspace {
                         item_tasks.push(task);
                         leader_view_ids.push(id);
                         break;
-                    } else {
-                        assert!(variant.is_some());
+                    } else if variant.is_none() {
+                        Err(anyhow!(
+                            "failed to construct view from leader (maybe from a different version of zed?)"
+                        ))?;
                     }
                 }
             }