Fix lsp client path comparisons on Windows

The api method for finding an LSP client for a given document URI was
written to stop traversing when encountering the OS root. This logic
assumed POSIX paths and did not work correctly on Windows platforms.

This updates the clojure-lsp client ids to use the uri.fsPath which is
platform agnostic and updates the root path comparison in the lsp api to
compare in a platform agnostic manner.

src/lsp/api.ts

@@ -13,6 +13,15 @@ export const clientIsAlive = (client: defs.LspClient) => {
   return [defs.LspStatus.Starting, defs.LspStatus.Running].includes(client.status);
 };
 
+/**
+ * Checks if a given path is the root of the filesystem in a platform agnostic manner (this should
+ * work identically on POSIX and Windows)
+ */
+const isRoot = (dir: string) => {
+  const normalized = path.normalize(dir);
+  return path.dirname(normalized) === normalized;
+};
+
 /**
  * Find the closest, active clojure-lsp client to a given URI. This works by traversing up the path component of the
  * provided URI until a client at the same level is found. This works because clients in the LspClientStore use their
@@ -23,13 +32,13 @@ export const clientIsAlive = (client: defs.LspClient) => {
  * must be explicitly referenced.
  */
 export const getActiveClientForUri = (clients: defs.LspClientStore, uri: vscode.Uri) => {
-  let current = uri.path;
-  while (current !== '/') {
+  let current = uri.fsPath;
+  while (!isRoot(current)) {
     const client = clients.get(current);
     if (client && clientIsAlive(client)) {
       return client;
     }
-    current = path.resolve(current, '..');
+    current = path.join(current, '..');
   }
   const fallback_client = clients.get(FALLBACK_CLIENT_ID);
   if (fallback_client && clientIsAlive(fallback_client)) {

src/lsp/commands/vscode-commands.ts

@@ -11,7 +11,7 @@ export const filterOutRootsWithClients = (
   clients: defs.LspClientStore
 ) => {
   return uris.filter((root) => {
-    const client = clients.get(root.uri.path);
+    const client = clients.get(root.uri.fsPath);
     return !client || !api.clientIsAlive(client);
   });
 };

src/lsp/provider.ts

@@ -101,7 +101,7 @@ export const createClientProvider = (params: CreateClientProviderParams) => {
   };
 
   let lsp_server_path: Promise<string | void> | undefined = undefined;
-  const provisionClient = async (uri: vscode.Uri, id = uri.path) => {
+  const provisionClient = async (uri: vscode.Uri, id = uri.fsPath) => {
     if (lsp_server_path === undefined) {
       lsp_server_path = lsp_client.ensureLSPServer(params.context).catch((err) => {
         console.error('Failed to download lsp server', err);