Cache parsed stacks

Since we can only trigger prepareStackFrame once, it's important to cache
this since the second time it gets accessed we won't be able to get to it.

Author: sebmarkbage

packages/react-server/src/ReactFlightServer.js

@@ -152,11 +152,27 @@ function defaultFilterStackFrame(
   );
 }
 
+// DEV-only cache of parsed and filtered stack frames.
+const stackTraceCache: WeakMap<Error, ReactStackTrace> = __DEV__
+  ? new WeakMap()
+  : (null: any);
+
 function filterStackTrace(
   request: Request,
   error: Error,
   skipFrames: number,
 ): ReactStackTrace {
+  const existing = stackTraceCache.get(error);
+  if (existing !== undefined) {
+    // Return a clone because the Flight protocol isn't yet resilient to deduping
+    // objects in the debug info. TODO: Support deduping stacks.
+    const clone = existing.slice(0);
+    for (let i = 0; i < clone.length; i++) {
+      // $FlowFixMe[invalid-tuple-arity]
+      clone[i] = clone[i].slice(0);
+    }
+    return clone;
+  }
   // Since stacks can be quite large and we pass a lot of them, we filter them out eagerly
   // to save bandwidth even in DEV. We'll also replay these stacks on the client so by
   // stripping them early we avoid that overhead. Otherwise we'd normally just rely on
@@ -183,6 +199,7 @@ function filterStackTrace(
       i--;
     }
   }
+  stackTraceCache.set(error, stack);
   return stack;
 }