From e9b280afe00815cced8c50ca6e97d7987e5782ec Mon Sep 17 00:00:00 2001
From: KyleBarton <kjb@initialcapacity.io>
Date: Fri, 3 Apr 2026 14:55:12 -0700
Subject: [PATCH] Account for windows absolute paths in bind mounts (#53093)

Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [x] Unsafe blocks (if any) have justifying comments
- [x] The content is consistent with the [UI/UX
checklist](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
- [x] Tests cover the new/changed behavior
- [x] Performance impact has been considered and is acceptable

Addresses an auxiliary windows bug found in #52924 - bind mounts are not
working in Windows because MountDefinition is not accounting for
absolute Windows paths.

Release Notes:

- Fixed windows bind mount issue with dev containers
---
 crates/dev_container/src/devcontainer_json.rs | 54 ++++++++++++++++++-
 1 file changed, 53 insertions(+), 1 deletion(-)

diff --git a/crates/dev_container/src/devcontainer_json.rs b/crates/dev_container/src/devcontainer_json.rs
index 4429c63a37a87d1b54455b8169359ddf40511e24..f034026a8de4c4a6c3186c97870e25f3510ebc85 100644
--- a/crates/dev_container/src/devcontainer_json.rs
+++ b/crates/dev_container/src/devcontainer_json.rs
@@ -72,7 +72,11 @@ impl Display for MountDefinition {
             f,
             "type={},source={},target={},consistency=cached",
             self.mount_type.clone().unwrap_or_else(|| {
-                if self.source.starts_with('/') {
+                if self.source.starts_with('/')
+                    || self.source.starts_with("\\\\")
+                    || self.source.get(1..3) == Some(":\\")
+                    || self.source.get(1..3) == Some(":/")
+                {
                     "bind".to_string()
                 } else {
                     "volume".to_string()
@@ -1355,4 +1359,52 @@ mod test {
 
         assert_eq!(devcontainer.build_type(), DevContainerBuildType::Dockerfile);
     }
+
+    #[test]
+    fn mount_definition_should_use_bind_type_for_unix_absolute_paths() {
+        let mount = MountDefinition {
+            source: "/home/user/project".to_string(),
+            target: "/workspaces/project".to_string(),
+            mount_type: None,
+        };
+
+        let rendered = mount.to_string();
+
+        assert!(
+            rendered.starts_with("type=bind,"),
+            "Expected mount type 'bind' for Unix absolute path, but got: {rendered}"
+        );
+    }
+
+    #[test]
+    fn mount_definition_should_use_bind_type_for_windows_unc_paths() {
+        let mount = MountDefinition {
+            source: "\\\\server\\share\\project".to_string(),
+            target: "/workspaces/project".to_string(),
+            mount_type: None,
+        };
+
+        let rendered = mount.to_string();
+
+        assert!(
+            rendered.starts_with("type=bind,"),
+            "Expected mount type 'bind' for Windows UNC path, but got: {rendered}"
+        );
+    }
+
+    #[test]
+    fn mount_definition_should_use_bind_type_for_windows_absolute_paths() {
+        let mount = MountDefinition {
+            source: "C:\\Users\\mrg\\cli".to_string(),
+            target: "/workspaces/cli".to_string(),
+            mount_type: None,
+        };
+
+        let rendered = mount.to_string();
+
+        assert!(
+            rendered.starts_with("type=bind,"),
+            "Expected mount type 'bind' for Windows absolute path, but got: {rendered}"
+        );
+    }
 }