reroute stderr through printer and ensure printing is done around spinners (#2596)

Author: Amplifiyer

.changeset/floppy-pianos-fold.md

@@ -0,0 +1,6 @@
+---
+'@aws-amplify/cli-core': patch
+'@aws-amplify/sandbox': patch
+---
+
+reroute stderr through printer and ensure printing is done around spinners

packages/cli-core/src/printer/printer.ts

@@ -33,13 +33,8 @@ export class Printer {
   print = (message: string) => {
     message = this.stringify(message);
     if (this.isSpinnerRunning()) {
-      if (this.currentSpinner.instance?.prefixText) {
-        const spinnerPrefixMessage = this.currentSpinner.instance?.prefixText;
-        this.currentSpinner.instance.prefixText =
-          message + EOL + spinnerPrefixMessage;
-        return;
-      }
-      this.printNewLine();
+      this.printWhileSpinnerRunning(message);
+      return;
     }
     if (!this.ttyEnabled) {
       message = stripANSI(message);
@@ -189,6 +184,21 @@ export class Printer {
     process.stdout.moveCursor(0, -lines);
   };
 
+  private printWhileSpinnerRunning = (message: string) => {
+    if (this.isSpinnerRunning()) {
+      if (this.currentSpinner.instance?.prefixText) {
+        const spinnerPrefixMessage = this.currentSpinner.instance?.prefixText;
+        this.currentSpinner.instance.prefixText =
+          message + EOL + spinnerPrefixMessage;
+      } else {
+        const spinnerMessage = this.currentSpinner.instance?.text;
+        this.currentSpinner.instance?.clear();
+        this.stdout.write(message);
+        this.currentSpinner.instance?.start(spinnerMessage);
+      }
+    }
+  };
+
   private stringify = (msg: unknown): string => {
     if (typeof msg === 'string') {
       return msg;

packages/sandbox/src/file_watching_sandbox.ts

@@ -449,17 +449,22 @@ export class FileWatchingSandbox extends EventEmitter implements Sandbox {
    * Hack to suppress certain stderr messages until aws-cdk constructs
    * can use the toolkit's IoHost to deliver messages.
    * See tracking items https://github.com/aws/aws-cdk-cli/issues/158
+   *
+   * Rest of the stderr messages are rerouted to our printer so that they
+   * don't get intermingled with spinners.
    */
   private interceptStderr = () => {
-    const originalStderrWrite = process.stderr.write.bind(process.stderr);
     process.stderr.write = (chunk) => {
       if (
         typeof chunk !== 'string' ||
-        !['/index.mjs', '/index.mjs.map', 'Bundling asset', '⚡ Done in '].some(
-          (prohibitedStrings) => chunk.includes(prohibitedStrings),
+        !['Bundling asset'].some((prohibitedStrings) =>
+          chunk.includes(prohibitedStrings),
         )
-      )
-        return originalStderrWrite(chunk);
+      ) {
+        this.printer.log(
+          typeof chunk === 'string' ? chunk : chunk.toLocaleString(),
+        );
+      }
       return true;
     };
   };