Fix check for clangd.restart being a no-op (#601)

The intention was to only catch the case where the language server
is already starting because running the restart command triggered
activation of the plugin, but it was also catching the case where
the language server wasn't running at all.

Fixes #599

src/clangd-context.ts

@@ -191,8 +191,8 @@ export class ClangdContext implements vscode.Disposable {
         (e) => isClangdDocument(e.document));
   }
 
-  clientIsReady() {
-    return this.client && this.client.state == vscodelc.State.Running;
+  clientIsStarting() {
+    return this.client && this.client.state == vscodelc.State.Starting;
   }
 
   dispose() {

src/extension.ts

@@ -25,7 +25,7 @@ export async function activate(context: vscode.ExtensionContext) {
         // stop/start cycle in this situation is pointless, and doesn't work
         // anyways because the client can't be stop()-ped when it's still in the
         // Starting state).
-        if (!clangdContext.clientIsReady()) {
+        if (clangdContext.clientIsStarting()) {
           return;
         }
         await clangdContext.dispose();

test/inactive-regions.test.ts

@@ -16,7 +16,7 @@ class MockClangdContext implements ClangdContext {
 
   async activate() { throw new Error('Method not implemented.'); }
 
-  clientIsReady() { return true; }
+  clientIsStarting() { return false; }
 
   dispose() { throw new Error('Method not implemented.'); }
 }