Inform on fallback to outdated hls only on first download

Author: mduerig

src/hlsBinaries.ts

@@ -365,25 +365,27 @@ export async function downloadHaskellLanguageServer(
     window.showInformationMessage(new NoBinariesError(releases[0].tag_name, ghcVersion).message);
     return null;
   }
-  if (release?.tag_name != releases[0].tag_name) {
-    const message = `haskell-language-server ${releases[0].tag_name} for GHC ${ghcVersion} is not available on ${os.type()}. Falling back to haskell-language-server ${release?.tag_name}`
-    logger.warn(message)
-    window.showInformationMessage(message)
-  }
 
   const serverName = `haskell-language-server-${release?.tag_name}-${process.platform}-${ghcVersion}${exeExt}`;
   const binaryDest = path.join(storagePath, serverName);
 
   const title = `Downloading haskell-language-server ${release?.tag_name} for GHC ${ghcVersion}`;
   logger.info(title);
-  await downloadFile(title, asset.browser_download_url, binaryDest);
+  const downloaded = await downloadFile(title, asset.browser_download_url, binaryDest);
   if (ghcVersion.startsWith('9.')) {
     const warning =
       'Currently, HLS supports GHC 9 only partially. ' +
       'See [issue #297](https://github.com/haskell/haskell-language-server/issues/297) for more detail.';
     logger.warn(warning);
     window.showWarningMessage(warning);
   }
+  if (release?.tag_name != releases[0].tag_name) {
+    const warning = `haskell-language-server ${releases[0].tag_name} for GHC ${ghcVersion} is not available on ${os.type()}. Falling back to haskell-language-server ${release?.tag_name}`
+    logger.warn(warning)
+    if (downloaded) {
+      window.showInformationMessage(warning)
+    }
+  }
   return binaryDest;
 }
 

src/utils.ts

@@ -95,7 +95,7 @@ const userAgentHeader = { 'User-Agent': 'vscode-haskell' };
  * equality is by reference, not value in Map. And we are using a tuple of
  * [src, dest] as the key.
  */
-const inFlightDownloads = new Map<string, Map<string, Thenable<void>>>();
+const inFlightDownloads = new Map<string, Map<string, Thenable<boolean>>>();
 
 export async function httpsGetSilently(options: https.RequestOptions): Promise<string> {
   const opts: https.RequestOptions = {
@@ -141,7 +141,7 @@ async function ignoreFileNotExists(err: NodeJS.ErrnoException): Promise<void> {
   throw err;
 }
 
-export async function downloadFile(titleMsg: string, src: string, dest: string): Promise<void> {
+export async function downloadFile(titleMsg: string, src: string, dest: string): Promise<boolean> {
   // Check to see if we're already in the process of downloading the same thing
   const inFlightDownload = inFlightDownloads.get(src)?.get(dest);
   if (inFlightDownload) {
@@ -150,7 +150,7 @@ export async function downloadFile(titleMsg: string, src: string, dest: string):
 
   // If it already is downloaded just use that
   if (fs.existsSync(dest)) {
-    return;
+    return false;
   }
 
   // Download it to a .tmp location first, then rename it!
@@ -241,7 +241,7 @@ export async function downloadFile(titleMsg: string, src: string, dest: string):
         inFlightDownloads.get(src)?.delete(dest);
       }
     }
-  );
+  ).then(_ => true);
 
   try {
     if (inFlightDownloads.has(src)) {