Fix tests

packages/react-devtools-extensions/webpack.backend.js

@@ -78,6 +78,7 @@ module.exports = {
       __IS_FIREFOX__: IS_FIREFOX,
       __IS_EDGE__: IS_EDGE,
       __IS_NATIVE__: false,
+      __IS_INTERNAL_MCP_BUILD__: false,
     }),
     new Webpack.SourceMapDevToolPlugin({
       filename: '[file].map',

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

@@ -5113,6 +5113,151 @@
   let rootToCommitProfilingMetadataMap: CommitProfilingMetadataMap | null =
     null;
 
+  function printPerformanceData(profilingData: ProfilingDataBackend): void {
+    if (
+      !profilingData ||
+      !profilingData.dataForRoots ||
+      profilingData.dataForRoots.length === 0
+    ) {
+      console.log('No profiling data available');
+      return;
+    }
+
+    console.group('React Performance Data');
+
+    profilingData.dataForRoots.forEach(rootData => {
+      const {commitData, displayName, initialTreeBaseDurations} = rootData;
+
+      console.group(`Root: ${displayName}`);
+
+      // Print overall stats
+      const totalCommits = commitData.length;
+      const totalCommitDuration = commitData.reduce(
+        (sum, commit) => sum + commit.duration,
+        0,
+      );
+      const avgCommitDuration = totalCommitDuration / totalCommits;
+
+      console.log(`Total commits: ${totalCommits}`);
+      console.log(`Average commit duration: ${avgCommitDuration.toFixed(2)}ms`);
+
+      // Find slow components (components that took a long time to render)
+      const componentDurations = new Map();
+
+      commitData.forEach(commit => {
+        if (commit.fiberActualDurations) {
+          commit.fiberActualDurations.forEach(([fiberID, duration]) => {
+            if (!componentDurations.has(fiberID)) {
+              componentDurations.set(fiberID, []);
+            }
+            componentDurations.get(fiberID).push(duration);
+          });
+        }
+      });
+
+      // Calculate average render times for each component
+      const averageComponentDurations = new Map();
+      componentDurations.forEach((durations, fiberID) => {
+        const total = durations.reduce((sum, duration) => sum + duration, 0);
+        const average = total / durations.length;
+        averageComponentDurations.set(fiberID, {
+          average,
+          count: durations.length,
+          total,
+        });
+      });
+
+      // Sort components by average render time (descending)
+      const sortedComponents = Array.from(
+        averageComponentDurations.entries(),
+      ).sort((a, b) => b[1].average - a[1].average);
+
+      // Print the top 10 slowest components
+      console.group('Top 10 slowest components (by average render time)');
+      sortedComponents
+        .slice(0, 10)
+        .forEach(([fiberID, {average, count, total}]) => {
+          // Try to find component name from snapshots
+          let componentName = `FiberID: ${fiberID}`;
+          if (rootData.snapshots) {
+            const snapshot = rootData.snapshots.find(
+              snap => snap[0] === fiberID,
+            );
+            if (snapshot && snapshot[1] && snapshot[1].displayName) {
+              componentName = snapshot[1].displayName;
+            }
+          }
+
+          console.log(
+            `${componentName}: ${average.toFixed(2)}ms avg (${count} renders, ${total.toFixed(2)}ms total)`,
+          );
+        });
+      console.groupEnd();
+
+      // Print components with most renders
+      const sortedByRenderCount = Array.from(
+        averageComponentDurations.entries(),
+      ).sort((a, b) => b[1].count - a[1].count);
+
+      console.group('Top 10 most frequently rendered components');
+      sortedByRenderCount
+        .slice(0, 10)
+        .forEach(([fiberID, {average, count, total}]) => {
+          // Try to find component name from snapshots
+          let componentName = `FiberID: ${fiberID}`;
+          if (rootData.snapshots) {
+            const snapshot = rootData.snapshots.find(
+              snap => snap[0] === fiberID,
+            );
+            if (snapshot && snapshot[1] && snapshot[1].displayName) {
+              componentName = snapshot[1].displayName;
+            }
+          }
+
+          console.log(
+            `${componentName}: ${count} renders (${average.toFixed(2)}ms avg, ${total.toFixed(2)}ms total)`,
+          );
+        });
+      console.groupEnd();
+
+      // Print effect durations if available
+      const effectDurations = commitData
+        .filter(commit => commit.effectDuration !== null)
+        .map(commit => commit.effectDuration);
+
+      const passiveEffectDurations = commitData
+        .filter(commit => commit.passiveEffectDuration !== null)
+        .map(commit => commit.passiveEffectDuration);
+
+      if (effectDurations.length > 0) {
+        const totalEffectDuration = effectDurations.reduce(
+          (sum, duration) => sum + duration,
+          0,
+        );
+        const avgEffectDuration = totalEffectDuration / effectDurations.length;
+        console.log(
+          `Average effect duration: ${avgEffectDuration.toFixed(2)}ms`,
+        );
+      }
+
+      if (passiveEffectDurations.length > 0) {
+        const totalPassiveEffectDuration = passiveEffectDurations.reduce(
+          (sum, duration) => sum + duration,
+          0,
+        );
+        const avgPassiveEffectDuration =
+          totalPassiveEffectDuration / passiveEffectDurations.length;
+        console.log(
+          `Average passive effect duration: ${avgPassiveEffectDuration.toFixed(2)}ms`,
+        );
+      }
+
+      console.groupEnd(); // Root group
+    });
+
+    console.groupEnd(); // React Performance Data group
+  }
+
   function getProfilingData(): ProfilingDataBackend {
     const dataForRoots: Array<ProfilingDataForRootBackend> = [];
 
@@ -5205,7 +5350,7 @@
           ...rest
         } = currentTimelineData;
 
         timelineData = {
           ...rest,
 
           // Most of the data is safe to parse as-is,
@@ -5226,11 +5371,16 @@
       }
     }
 
-    return {
+    const profilingData = {
       dataForRoots,
       rendererID,
-      timelineData,
+      timelineData: getTimelineData?.() || null,
     };
+
+    // Print the performance data to help with debugging
+    printPerformanceData(profilingData);
+
+    return profilingData;
   }
 
   function snapshotTreeBaseDurations(

scripts/jest/devtools/setupEnv.js

@@ -15,6 +15,7 @@ global.__IS_FIREFOX__ = false;
 global.__IS_CHROME__ = false;
 global.__IS_EDGE__ = false;
 global.__IS_NATIVE__ = false;
+global.__IS_INTERNAL_MCP_BUILD__ = false;
 
 const ReactVersionTestingAgainst = process.env.REACT_VERSION || ReactVersion;