install: fix npm dependencies that share a workspace member's name

src/install/PackageInstall.rs

@@ -2276,8 +2276,20 @@ impl<'a> PackageInstall<'a> {
             dest_name_buf[..dest.len()].copy_from_slice(dest);
             // SAFETY: zero-initialized; NUL at [dest.len()].
             let dest_z = ZStr::from_buf(&dest_name_buf, dest.len());
-            if let Err(err) = sys::symlinkat(target_z, dest_dir.fd(), dest_z) {
-                return InstallResult::fail(err.into(), Step::LinkingDependency, None);
+            if let Err(first_err) = sys::symlinkat(target_z, dest_dir.fd(), dest_z) {
+                // A stale entry can survive `skip_delete`: a workspace
+                // member's internal node_modules is not reset by wiping the
+                // root node_modules. Replace it and retry, like the Windows
+                // branch above.
+                let retry = first_err.get_errno() == sys::E::EEXIST;
+                let mut result = Err(first_err);
+                if retry {
+                    self.uninstall_before_install(destination_dir);
+                    result = sys::symlinkat(target_z, dest_dir.fd(), dest_z);
+                }
+                if let Err(err) = result {
+                    return InstallResult::fail(err.into(), Step::LinkingDependency, None);
+                }
             }
         }
 

src/install/isolated_install/Installer.rs

@@ -534,6 +534,16 @@ impl<'a> Installer<'a> {
                 break 'state (node_id, CompleteState::Skipped);
             }
 
+            // A member displaced by a root dependency is reachable only
+            // through non-workspace edges, and workspace store tasks re-run
+            // every install, so a completed one is not an install.
+            let pkg_id = nodes.items_pkg_id()[node_id.get() as usize];
+            if self.lockfile().packages.slice().items_resolution()[pkg_id as usize].tag
+                == ResolutionTag::Workspace
+            {
+                break 'state (node_id, CompleteState::Skipped);
+            }
+
             break 'state (node_id, state);
         };
 

src/install/lockfile/Package.rs

@@ -1750,31 +1750,41 @@ impl Package<u64> {
                     .append::<String>(if relative.is_empty() { b"." } else { relative });
             }
             dependency::version::Tag::Npm => {
-                if let Some(workspace_version) = workspace_version {
-                    let satisfies =
-                        dependency_version
-                            .npm()
-                            .version
-                            .satisfies(workspace_version, buf, buf);
+                if workspace_path.is_some() {
+                    let satisfies = match workspace_version {
+                        Some(workspace_version) => {
+                            dependency_version
+                                .npm()
+                                .version
+                                .satisfies(workspace_version, buf, buf)
+                        }
+                        // A versionless member is only linkable by a wildcard
+                        // range, matching `get_or_put_resolved_package`.
+                        None => dependency_version.npm().version.is_star(),
+                    };
                     if pm.options.link_workspace_packages && satisfies {
-                        // `String::sliced` takes `&'a self`; bind the unwrapped
-                        // value so the borrow outlives the parse call.
-                        let wp = workspace_path.unwrap();
-                        let path = wp.sliced(buf);
-                        if let Some(mut dep) = dependency::parse_with_tag(
-                            external_alias.value,
-                            Some(external_alias.hash),
-                            path.slice,
-                            dependency::version::Tag::Workspace,
-                            &path,
-                            Some(&mut *log),
-                            Some(&mut *pm),
-                        ) {
-                            // Whole-struct move so `Drop` frees the old npm
-                            // chain; keep the existing `literal`.
-                            dep.literal = dependency_version.literal;
-                            dependency_version = dep;
+                        if workspace_version.is_some() {
+                            // `String::sliced` takes `&'a self`; bind the unwrapped
+                            // value so the borrow outlives the parse call.
+                            let wp = workspace_path.unwrap();
+                            let path = wp.sliced(buf);
+                            if let Some(mut dep) = dependency::parse_with_tag(
+                                external_alias.value,
+                                Some(external_alias.hash),
+                                path.slice,
+                                dependency::version::Tag::Workspace,
+                                &path,
+                                Some(&mut *log),
+                                Some(&mut *pm),
+                            ) {
+                                // Whole-struct move so `Drop` frees the old npm
+                                // chain; keep the existing `literal`.
+                                dep.literal = dependency_version.literal;
+                                dependency_version = dep;
+                            }
                         }
+                        // For a versionless member the dependency stays as-is;
+                        // resolution links it to the workspace package.
                     } else {
                         // It doesn't satisfy, but a workspace shares the same name. Override the workspace with the other dependency
                         for dep in &mut package_dependencies[0..dependencies_count as usize] {

src/install/lockfile/bun.lock.rs

@@ -1604,6 +1604,10 @@
 ) -> Result<(), ParseError> {
     lockfile.init_empty();
 
+    let link_workspace_packages = manager
+        .as_deref()
+        .is_none_or(|m| m.options.link_workspace_packages);
+
     let Some(lockfile_version_expr) = root.get(b"lockfileVersion") else {
         log.add_error(Some(source), root.loc, b"Missing lockfile version");
         return Err(ParseError::InvalidLockfileVersion);
@@ -2091,6 +2095,7 @@
             None
         };
 
+        let root_pkgs_expr = root.get(b"packages");
         let (off, len) = parse_append_dependencies::<false, true>(
             lockfile,
             &root_pkg_exr,
@@ -2100,6 +2105,8 @@
             None,
             None,
             Some(&workspaces_obj),
+            root_pkgs_expr.as_ref(),
+            link_workspace_packages,
         )?;
 
         let mut root_pkg = Package::default();
@@ -2124,8 +2131,13 @@
     let workspace_pkgs_off: u32 = 1;
     let mut workspace_pkgs_len: u32 = 0;
 
+    // Workspace-name duplicate detection, decoupled from the conditional
+    // `pkg_map` claim below so it fires even for displaced members.
+    let mut seen_workspace_names: PkgPathSet = PkgPathSet::init();
+
     if lockfile_version != Version::V0 {
         // these are the `workspaceOnly` packages
+        let pkgs_expr_for_claims = root.get(b"packages");
         // snapshot the workspace-path handles up front so the loop
         // body can take `&mut *lockfile` (`parse_append_dependencies`,
         // `append_package_dedupe`) without conflicting with the
@@ -2156,6 +2168,16 @@
                     .expect("infallible: is_string checked");
                 let name_hash = StringBuilder::string_hash(name);
 
+                if seen_workspace_names.contains(name) {
+                    log.add_error_fmt(
+                        source,
+                        row.key_loc,
+                        format_args!("Duplicate workspace name: '{}'", bstr::BStr::new(name)),
+                    );
+                    return Err(ParseError::InvalidWorkspaceObject);
+                }
+                seen_workspace_names.put(name, ());
+
                 pkg.name = sbuf!(lockfile).append_with_hash(name, name_hash)?;
                 pkg.name_hash = name_hash;
 
@@ -2168,6 +2190,8 @@
                     None,
                     None,
                     None,
+                    None,
+                    link_workspace_packages,
                 )?;
 
                 pkg.dependencies = DependencySlice::new(off, len);
@@ -2185,21 +2209,24 @@
                 }
 
                 // there should be no duplicates
+                let pkgs_len_before = lockfile.packages.len();
                 let pkg_id = lockfile.append_package_dedupe(&mut pkg)?;
 
-                let entry = pkg_map.get_or_put(name)?;
-                if entry.found_existing {
-                    log.add_error_fmt(
-                        source,
-                        row.key_loc,
-                        format_args!("Duplicate workspace name: '{}'", bstr::BStr::new(name)),
-                    );
-                    return Err(ParseError::InvalidWorkspaceObject);
+                // A member displaced by a root dependency only appears
+                // nested; pre-claiming its name would falsely collide with
+                // the root `packages` key the other package owns.
+                if member_owns_packages_key(pkgs_expr_for_claims.as_ref(), name, path) {
+                    let entry = pkg_map.get_or_put(name)?;
+                    debug_assert!(!entry.found_existing, "caught by seen_workspace_names");
+                    *entry.value_ptr = pkg_id;
                 }
 
-                *entry.value_ptr = pkg_id;
-
-                workspace_pkgs_len += 1;
+                // `workspace_pkgs_len` sizes the 1..1+len package-id range
+                // resolved below; it must count appended packages, not loop
+                // iterations.
+                if lockfile.packages.len() > pkgs_len_before {
+                    workspace_pkgs_len += 1;
+                }
                 continue 'workspaces;
             }
         }
@@ -2263,6 +2290,11 @@
             bundled_pkgs.put(pkg_path, ());
         }
 
+        // Workspace packages claimed under a `packages` key other than their
+        // name (nested under a dependent, or aliased). Their own dependency
+        // keys are written under that placement, e.g. "beta/member/dep".
+        let mut member_tree_keys: Vec<(PackageID, &[u8])> = Vec::new();
+
         'next_pkg_key: for row in object_rows(&pkgs_expr) {
             let key_loc = row.key_loc;
             let pkg_path = row.key.slice();
@@ -2454,6 +2486,7 @@
                             //   "another-pkg1": "workspaces:packages/pkg1",
                             // },
                             *entry.value_ptr = workspace_pkg_id;
+                            member_tree_keys.push((workspace_pkg_id, pkg_path));
                             continue 'next_pkg_key;
                         }
                     }
@@ -2521,6 +2554,8 @@
                             Some(pkg_path),
                             Some(&bundled_pkgs),
                             None,
+                            None,
+                            link_workspace_packages,
                         )?;
 
                         pkg.dependencies = DependencySlice::new(off, len);
@@ -2853,6 +2888,25 @@
                     let dep = &mut dependencies[dep_id as usize];
                     let dep_name = dep.name.slice(string_buf);
 
+                    // A displaced member's node lives under its recorded
+                    // `packages` key (e.g. "beta/member"), so its own
+                    // dependency keys are "beta/member/dep", not
+                    // "member/dep".
+                    let nested_res_id = member_tree_keys.iter().find_map(|&(id, key)| {
+                        if id != pkg_id {
+                            return None;
+                        }
+                        let needed = key.len() + 1 + dep_name.len();
+                        let buf_slice = &mut path_buf[..];
+                        if needed > buf_slice.len() {
+                            return None;
+                        }
+                        buf_slice[..key.len()].copy_from_slice(key);
+                        buf_slice[key.len()] = b'/';
+                        buf_slice[key.len() + 1..needed].copy_from_slice(dep_name);
+                        pkg_map.get(&buf_slice[..needed]).copied()
+                    });
+
                     let workspace_node_modules = {
                         let buf_slice = &mut path_buf[..];
                         let needed = workspace_name.len() + 1 + dep_name.len();
@@ -2882,10 +2936,10 @@
                             pkg_resolutions,
                             string_buf,
                         )
                     } else {
                         None
                     };
-                    let Some(res_id) = peer_res_id.or_else(|| {
+                    let Some(res_id) = peer_res_id.or(nested_res_id).or_else(|| {
                         pkg_map
                             .get(workspace_node_modules)
                             .or_else(|| pkg_map.get(dep_name))
@@ -3153,6 +3207,33 @@
     }
 }
 
+/// A workspace member normally owns the root `packages` key matching its
+/// name. When a root dependency replaced the member's workspace dependency
+/// (`Package::parse_dependency`), that key holds the other package and the
+/// member only appears nested, so its name must not pre-claim the key.
+fn member_owns_packages_key(pkgs_expr: Option<&Expr>, name: &[u8], path: &[u8]) -> bool {
+    let Some(pkgs) = pkgs_expr else {
+        return true;
+    };
+    let Some(value) = pkgs.get(name) else {
+        return true;
+    };
+    if !value.is_array() {
+        return true;
+    }
+    let Some(first) = array_items(&value).first().and_then(|item| item.as_str()) else {
+        return true;
+    };
+    // a member's own entry is written as "<name>@workspace:<path>"
+    let Some(rest) = first.get(name.len() + 1..) else {
+        return false;
+    };
+    strings::has_prefix(first, name)
+        && first[name.len()] == b'@'
+        && strings::has_prefix(rest, b"workspace:")
+        && strings::eql(&rest[b"workspace:".len()..], path)
+}
+
 fn dependency_resolution_failure(
     dep: &Dependency,
     pkg_path: Option<&[u8]>,
@@ -3213,6 +3294,9 @@
     pkg_path: Option<&[u8]>,
     bundled_pkgs: Option<&PkgPathSet>,
     workspaces_obj: Option<&Expr>,
+    // Only meaningful when `IS_ROOT`.
+    pkgs_expr: Option<&Expr>,
+    link_workspace_packages: bool,
 ) -> Result<(u32, u32), ParseError> {
     // Clearing on entry is equivalent to clearing on every exit path for all
     // callers (none read the buf between calls) and also covers early-error exits.
@@ -3362,6 +3446,43 @@
                     .expect("infallible: is_string checked");
                 let name_hash = StringBuilder::string_hash(name);
 
+                // A member whose root `packages` key is owned by another
+                // package had its workspace dependency replaced when the
+                // lockfile was written; honor that recorded shape rather
+                // than re-deriving it from the current config, so a
+                // `linkWorkspacePackages` flip re-resolves through the
+                // normal changes diff instead of binding a workspace edge
+                // to the npm package. The range scan mirrors
+                // `Package::parse_dependency` for aliased dependencies,
+                // whose root key is the alias.
+                let overridden = {
+                    let bytes = lockfile.buffers.string_bytes.as_slice();
+                    !member_owns_packages_key(pkgs_expr, name, path) || {
+                        let member_version =
+                            lockfile.workspace_versions.get(&name_hash).copied();
+                        lockfile.buffers.dependencies.as_slice()[off..]
+                            .iter()
+                            .any(|dep| {
+                                if dep.version.tag != DependencyVersionTag::Npm {
+                                    return false;
+                                }
+                                let npm = dep.version.npm();
+                                if StringBuilder::string_hash(npm.name.slice(bytes)) != name_hash
+                                {
+                                    return false;
+                                }
+                                let satisfies = match member_version {
+                                    Some(version) => npm.version.satisfies(version, bytes, bytes),
+                                    None => npm.version.is_star(),
+                                };
+                                !(link_workspace_packages && satisfies)
+                            })
+                    }
+                };
+                if overridden {
+                    continue 'workspaces;
+                }
+
                 let dep = Dependency {
                     name: sbuf!(lockfile).append_with_hash(name, name_hash)?,
                     name_hash,