style: add comments to the code

Author: nodkz

packages/jest-worker/src/workers/messageParent.ts

@@ -20,6 +20,9 @@ export default function messageParent(
       parentProcess.send([PARENT_MESSAGE_CUSTOM, message]);
     } catch (e: any) {
       if (/circular structure/.test(e?.message)) {
+        // We can safely send a message to the parent process again
+        // because previous sending was halted by "TypeError: Converting circular structure to JSON".
+        // But this time the message will be cleared from circular references.
         parentProcess.send([
           PARENT_MESSAGE_CUSTOM,
           withoutCircularRefs(message),

packages/jest-worker/src/workers/processChild.ts

@@ -101,6 +101,9 @@ function reportSuccess(result: unknown) {
   try {
     process.send([PARENT_MESSAGE_OK, result]);
   } catch (e: any) {
+    // We can safely send a message to the parent process again
+    // because previous sending was halted by "TypeError: Converting circular structure to JSON".
+    // But this time the message will be cleared from circular references.
     if (e && /circular structure/.test(e?.message)) {
       process.send([PARENT_MESSAGE_OK, withoutCircularRefs(result)]);
     } else {