Create a text file to not show Release notes

Release Notes should only be shown at the very first installation
and activation of a new version of the extension.

If you want to view the Release Notes any other time then you
will have to call the Command Pallete

Author: gnikit

src/extension.ts

@@ -1,6 +1,10 @@
-// src/extension.ts
+'use strict';
+
 import * as vscode from 'vscode';
 import * as pkg from '../package.json';
+import * as path from 'path';
+import * as fs from 'fs';
+
 import { FortranCompletionProvider } from './features/completion-provider';
 import { FortranDocumentSymbolProvider } from './features/document-symbol-provider';
 import { FortranFormattingProvider } from './features/formatting-provider';
@@ -9,6 +13,7 @@ import { FortranHoverProvider } from './features/hover-provider';
 import { FortranLintingProvider } from './features/linter-provider';
 import { EXTENSION_ID, FortranDocumentSelector } from './lib/tools';
 import { LoggingService } from './services/logging-service';
+import { WhatsNew } from './features/commands';
 
 // Make it global to catch errors when activation fails
 const loggingService = new LoggingService();
@@ -87,6 +92,14 @@ export async function activate(context: vscode.ExtensionContext) {
       },
     })
   );
+
+  context.subscriptions.push(vscode.commands.registerCommand(WhatsNew, showWhatsNew));
+  // Upon the very first initialisation create a file to indicate that the release
+  // notes have been shown and not show them again.
+  if (!fs.existsSync(path.join(__dirname, 'displayReleaseNotes.txt'))) {
+    await showWhatsNew();
+    fs.writeFileSync(path.join(__dirname, 'displayReleaseNotes.txt'), 'false');
+  }
   return context;
 }
 
@@ -142,3 +155,8 @@ function detectDeprecatedOptions() {
       Please Disable/Uninstall extension: fortran.`);
   }
 }
+
+async function showWhatsNew() {
+  const uri = vscode.Uri.file(path.join(__dirname, '../updates/RELEASE_NOTES-v3.0.md'));
+  vscode.commands.executeCommand('markdown.showPreview', uri);
+}