Merge pull request #758 from ejgallego/client_dont_start_except_if_files

[code] Don't start the language client unless there is an active editor for us

CHANGES.md

@@ -29,6 +29,9 @@
    (@ejgallego, #762)
  - [lsp] [definition] Try also to resolve and locate module imports
    (@ejgallego, #764)
+ - [code] Don't start server on extension activation, unless an editor
+   we own is active. We also auto-start the server if a document that
+   we own is opened later (@ejgallego, #758, fixes #750)
 
 # coq-lsp 0.1.10: Hasta el 40 de Mayo _en effect_...
 ----------------------------------------------------

editor/code/src/client.ts

@@ -460,7 +460,7 @@ export function activateCoqLSP(
       0
     );
     lspStatusItem.command = "coq-lsp.toggle";
-    lspStatusItem.text = "coq-lsp (activating)";
+    lspStatusItem.text = "coq-lsp (not active)";
     lspStatusItem.show();
     context.subscriptions.push(lspStatusItem);
   };
@@ -521,7 +521,23 @@ export function activateCoqLSP(
 
   createEnableButton();
 
-  start();
+  // Fix for bug #750
+  const active_editors_for_us = (editors: readonly TextEditor[]) =>
+    editors.some(
+      (editor) => languages.match(CoqSelector.all, editor.document) > 0
+    );
+
+  // We track when new buffers appear, and start the client if so. We
+  // dispose of the hook too.
+  if (active_editors_for_us(window.visibleTextEditors)) {
+    start();
+  } else {
+    window.onDidChangeVisibleTextEditors((editors) => {
+      if (!client || !client.isRunning()) {
+        if (active_editors_for_us(editors)) start();
+      }
+    }, context.subscriptions);
+  }
 
   return {
     goalsRequest: (params) => {