[pull] main from facebook:main

packages/react-client/src/ReactFlightClient.js

@@ -3154,15 +3154,15 @@ function createFakeFunction<T>(
   }
 
   if (sourceMap) {
-    // We use the prefix rsc://React/ to separate these from other files listed in
+    // We use the prefix about://React/ to separate these from other files listed in
     // the Chrome DevTools. We need a "host name" and not just a protocol because
     // otherwise the group name becomes the root folder. Ideally we don't want to
     // show these at all but there's two reasons to assign a fake URL.
     // 1) A printed stack trace string needs a unique URL to be able to source map it.
     // 2) If source maps are disabled or fails, you should at least be able to tell
     //    which file it was.
     code +=
-      '\n//# sourceURL=rsc://React/' +
+      '\n//# sourceURL=about://React/' +
       encodeURIComponent(environmentName) +
       '/' +
       encodeURI(filename) +

packages/react-client/src/ReactFlightReplyClient.js

@@ -1095,15 +1095,15 @@ function createFakeServerFunction<A: Iterable<any>, T>(
   }
 
   if (sourceMap) {
-    // We use the prefix rsc://React/ to separate these from other files listed in
+    // We use the prefix about://React/ to separate these from other files listed in
     // the Chrome DevTools. We need a "host name" and not just a protocol because
     // otherwise the group name becomes the root folder. Ideally we don't want to
     // show these at all but there's two reasons to assign a fake URL.
     // 1) A printed stack trace string needs a unique URL to be able to source map it.
     // 2) If source maps are disabled or fails, you should at least be able to tell
     //    which file it was.
     code +=
-      '\n//# sourceURL=rsc://React/' +
+      '\n//# sourceURL=about://React/' +
       encodeURIComponent(environmentName) +
       '/' +
       encodeURI(filename) +

packages/react-client/src/__tests__/ReactFlight-test.js

@@ -1314,7 +1314,7 @@ describe('ReactFlight', () => {
         '    at async file:///testing.js:42:3',
         // third-party RSC frame
         // Ideally this would be a real frame produced by React not a mocked one.
-        '    at ThirdParty (rsc://React/ThirdParty/file:///code/%5Broot%2520of%2520the%2520server%5D.js?42:1:1)',
+        '    at ThirdParty (about://React/ThirdParty/file:///code/%5Broot%2520of%2520the%2520server%5D.js?42:1:1)',
         // We'll later filter this out based on line/column in `filterStackFrame`.
         '    at ThirdPartyModule (file:///file-with-index-source-map.js:52656:16374)',
         // host component in parent stack
@@ -3073,7 +3073,7 @@ describe('ReactFlight', () => {
         ReactNoopFlightClient.read(transport, {
           findSourceMapURL(url) {
             // By giving a source map url we're saying that we can't use the original
-            // file as the sourceURL, which gives stack traces a rsc://React/ prefix.
+            // file as the sourceURL, which gives stack traces a about://React/ prefix.
             return 'source-map://' + url;
           },
         }),
@@ -3147,7 +3147,7 @@ describe('ReactFlight', () => {
           expectedErrorStack={expectedErrorStack}>
           {ReactNoopFlightClient.read(transport, {
             findSourceMapURL(url, environmentName) {
-              if (url.startsWith('rsc://React/')) {
+              if (url.startsWith('about://React/')) {
                 // We don't expect to see any React prefixed URLs here.
                 sawReactPrefix = true;
               }

packages/react-devtools-shared/src/backend/fiber/DevToolsFiberComponentStack.js

@@ -199,7 +199,7 @@ export function getOwnerStackByFiberInDev(
       if (typeof owner.tag === 'number') {
         const fiber: Fiber = (owner: any);
         owner = fiber._debugOwner;
-        let debugStack = fiber._debugStack;
+        let debugStack: void | null | string | Error = fiber._debugStack;
         // If we don't actually print the stack if there is no owner of this JSX element.
         // In a real app it's typically not useful since the root app is always controlled
         // by the framework. These also tend to have noisy stacks because they're not rooted

packages/react-reconciler/src/ReactFiberComponentStack.js

@@ -177,20 +177,17 @@ export function getOwnerStackByFiberInDev(workInProgress: Fiber): string {
       if (typeof owner.tag === 'number') {
         const fiber: Fiber = (owner: any);
         owner = fiber._debugOwner;
-        let debugStack = fiber._debugStack;
+        const debugStack = fiber._debugStack;
         // If we don't actually print the stack if there is no owner of this JSX element.
         // In a real app it's typically not useful since the root app is always controlled
         // by the framework. These also tend to have noisy stacks because they're not rooted
         // in a React render but in some imperative bootstrapping code. It could be useful
         // if the element was created in module scope. E.g. hoisted. We could add a a single
         // stack frame for context for example but it doesn't say much if that's a wrapper.
         if (owner && debugStack) {
-          if (typeof debugStack !== 'string') {
-            // Stash the formatted stack so that we can avoid redoing the filtering.
-            fiber._debugStack = debugStack = formatOwnerStack(debugStack);
-          }
-          if (debugStack !== '') {
-            info += '\n' + debugStack;
+          const formattedStack = formatOwnerStack(debugStack);
+          if (formattedStack !== '') {
+            info += '\n' + formattedStack;
           }
         }
       } else if (owner.debugStack != null) {

packages/react-reconciler/src/ReactInternalTypes.js

@@ -200,7 +200,7 @@ export type Fiber = {
 
   _debugInfo?: ReactDebugInfo | null,
   _debugOwner?: ReactComponentInfo | Fiber | null,
-  _debugStack?: string | Error | null,
+  _debugStack?: Error | null,
   _debugTask?: ConsoleTask | null,
   _debugNeedsRemount?: boolean,
 

packages/react-server/src/ReactFlightServer.js

@@ -179,12 +179,12 @@ function defaultFilterStackFrame(
 }
 
 function devirtualizeURL(url: string): string {
-  if (url.startsWith('rsc://React/')) {
+  if (url.startsWith('about://React/')) {
     // This callsite is a virtual fake callsite that came from another Flight client.
     // We need to reverse it back into the original ___location by stripping its prefix
     // and suffix. We don't need the environment name because it's available on the
     // parent object that will contain the stack.
-    const envIdx = url.indexOf('/', 'rsc://React/'.length);
+    const envIdx = url.indexOf('/', 'about://React/'.length);
     const suffixIdx = url.lastIndexOf('?');
     if (envIdx > -1 && suffixIdx > -1) {
       return decodeURI(url.slice(envIdx + 1, suffixIdx));