Fixes fortls install prompt waiting before spawning fortls

Author: gnikit

src/extension.ts

@@ -64,17 +64,24 @@ export function activate(context: vscode.ExtensionContext) {
   }
 
   // Check if the language server is installed and if not prompt to install it
-  if (!which.sync('fortls', { nothrow: true })) {
-    const msg = `It is highly recommended to use the fortran-language-server to 
-              enable hover, peeking, gotos and many more.
+  // Not the most elegant solution but we need pip install to have finished
+  // before the activate function is called so we do a little code duplication
+  which(config.get<string>('fortls.path'), err => {
+    if (err) {
+      const msg = `It is highly recommended to use the fortran-language-server to
+              enable IDE features like hover, peeking, gotos and many more.
               For a full list of features the language server adds see:
               https://github.com/hansec/fortran-language-server`;
-    promptForMissingTool(LANG_SERVER_TOOL_ID, msg, 'Python', loggingService);
-  }
-
-  // Spawn the fortran-language-server
-  const fortls = new FortranLanguageServer(loggingService);
-  fortls.activate(context.subscriptions);
+      promptForMissingTool(LANG_SERVER_TOOL_ID, msg, 'Python', loggingService).then(() => {
+        const fortls = new FortranLanguageServer(loggingService);
+        fortls.activate(context.subscriptions);
+      });
+    } else {
+      // Spawn the fortran-language-server
+      const fortls = new FortranLanguageServer(loggingService);
+      fortls.activate(context.subscriptions);
+    }
+  });
 }
 
 function detectDeprecatedOptions() {

src/lib/tools.ts

@@ -50,15 +50,15 @@ export function FortranDocumentSelector(folder?: vscode.WorkspaceFolder) {
  * @param msg optional message for installing said package
  * @param toolType type of tool, supports `Python` (through pip) and 'VSExt'
  */
-export function promptForMissingTool(
+export async function promptForMissingTool(
   tool: string,
   msg: string,
   toolType: string,
   logger?: LoggingService
 ) {
   const items = ['Install'];
   return new Promise((resolve, reject) => {
-    resolve(
+    return resolve(
       vscode.window.showInformationMessage(msg, ...items).then(selected => {
         if (selected === 'Install') {
           switch (toolType) {
@@ -92,22 +92,22 @@ export function promptForMissingTool(
  * @param logger `optional` logging channel for output
  */
 export function installPythonTool(pyPackage: string, logger?: LoggingService) {
-  const installProcess = cp.spawn('pip', 'install --user --upgrade '.concat(pyPackage).split(' '));
-  installProcess.stdout.on('data', data => {
-    logger.logInfo(`pip install: ${data}`);
-  });
-  installProcess.on('exit', (code, signal) => {
-    if (code !== 0) {
-      logger.logError(
-        `Python package ${pyPackage} failed to install with code: ${code}, signal: ${signal}`
-      );
-    } else {
-      logger.logInfo(`Successfully installed ${pyPackage}.`);
-    }
-  });
-  installProcess.on('error', err => {
-    logger.logError(`${err}`);
-  });
+  const installProcess = cp.spawnSync(
+    'pip',
+    'install --user --upgrade '.concat(pyPackage).split(' ')
+  );
+  if (installProcess.error) {
+    logger.logError(
+      `Python package ${pyPackage} failed to install with code: ${installProcess.error}`
+    );
+  }
+  if (installProcess.stdout) {
+    const sep = '-'.repeat(80);
+    logger.logInfo(
+      `pip install --user --upgrade ${pyPackage}:\n${sep}\n${installProcess.stdout}${sep}`
+    );
+    logger.logInfo(`pip install was successful`);
+  }
 }
 
 /**