React sync for revisions 1c2876d...7a3416f

Reviewed By: bvaughn

Differential Revision: D7526137

fbshipit-source-id: 9f9db8a6b56cb4ae581a7b8d28079ec38de2180f

Libraries/Renderer/REVISION

@@ -1 +1 @@
-1c2876d5b558b8591feb335d8d7204bc46f7da8a
+7a3416f27532ac25849dfbc505300d469b43bbcc

Libraries/Renderer/ReactFabric-dev.js

@@ -4765,6 +4765,14 @@ var ReactStrictModeWarnings = {
   var didWarnAboutDeprecatedLifecycles = new Set();
   var didWarnAboutUnsafeLifecycles = new Set();
 
+  var setToSortedString = function(set) {
+    var array = [];
+    set.forEach(function(value) {
+      array.push(value);
+    });
+    return array.sort().join(", ");
+  };
+
   ReactStrictModeWarnings.discardPendingWarnings = function() {
     pendingComponentWillMountWarnings = [];
     pendingComponentWillReceivePropsWarnings = [];
@@ -4790,9 +4798,7 @@ var ReactStrictModeWarnings = {
 
           var formatted = lifecycle.replace("UNSAFE_", "");
           var suggestion = LIFECYCLE_SUGGESTIONS[lifecycle];
-          var sortedComponentNames = Array.from(componentNames)
+          var sortedComponentNames = setToSortedString(componentNames);
-            .sort()
-            .join(", ");
 
           lifecyclesWarningMesages.push(
             formatted +
@@ -4844,9 +4850,7 @@ var ReactStrictModeWarnings = {
         didWarnAboutDeprecatedLifecycles.add(fiber.type);
       });
 
-      var sortedNames = Array.from(uniqueNames)
+      var sortedNames = setToSortedString(uniqueNames);
-        .sort()
-        .join(", ");
 
       lowPriorityWarning$1(
         false,
@@ -4869,9 +4873,7 @@ var ReactStrictModeWarnings = {
         didWarnAboutDeprecatedLifecycles.add(fiber.type);
       });
 
-      var _sortedNames = Array.from(_uniqueNames)
+      var _sortedNames = setToSortedString(_uniqueNames);
-        .sort()
-        .join(", ");
 
       lowPriorityWarning$1(
         false,
@@ -4893,9 +4895,7 @@ var ReactStrictModeWarnings = {
         didWarnAboutDeprecatedLifecycles.add(fiber.type);
       });
 
-      var _sortedNames2 = Array.from(_uniqueNames2)
+      var _sortedNames2 = setToSortedString(_uniqueNames2);
-        .sort()
-        .join(", ");
 
       lowPriorityWarning$1(
         false,
@@ -6217,7 +6217,6 @@ var ReactFiberClassComponent = function(
       if (
         typeof instance.getSnapshotBeforeUpdate === "function" &&
         typeof instance.componentDidUpdate !== "function" &&
-        typeof instance.componentDidUpdate !== "function" &&
         !didWarnAboutGetSnapshotBeforeUpdateWithoutDidUpdate.has(type)
       ) {
         didWarnAboutGetSnapshotBeforeUpdateWithoutDidUpdate.add(type);
@@ -9199,6 +9198,10 @@ var ReactFiberBeginWork = function(
         changedBits,
         renderExpirationTime
       );
+    } else if (oldProps === newProps) {
+      // Skip over a memoized parent with a bitmask bailout even
+      // if we began working on it because of a deeper matching child.
+      return bailoutOnAlreadyFinishedWork(current, workInProgress);
     }
     // There is no bailout on `children` equality because we expect people
     // to often pass a bound method as a child, but it may reference

Libraries/Renderer/ReactFabric-prod.js

@@ -3656,33 +3656,40 @@ function ReactFiberBeginWork(
             renderExpirationTime
           );
         case 12:
-          fn = workInProgress.type;
+          a: {
-          unmaskedContext = workInProgress.pendingProps;
+            fn = workInProgress.type;
-          var oldProps = workInProgress.memoizedProps;
+            unmaskedContext = workInProgress.pendingProps;
-          props = fn._currentValue;
+            updateQueue = workInProgress.memoizedProps;
-          updateQueue = fn._changedBits;
+            props = fn._currentValue;
-          if (
+            var changedBits = fn._changedBits;
-            hasLegacyContextChanged() ||
+            if (
-            0 !== updateQueue ||
+              hasLegacyContextChanged() ||
-            oldProps !== unmaskedContext
+              0 !== changedBits ||
-          ) {
+              updateQueue !== unmaskedContext
-            workInProgress.memoizedProps = unmaskedContext;
+            ) {
-            oldProps = unmaskedContext.unstable_observedBits;
+              workInProgress.memoizedProps = unmaskedContext;
-            if (void 0 === oldProps || null === oldProps) oldProps = 1073741823;
+              var observedBits = unmaskedContext.unstable_observedBits;
-            workInProgress.stateNode = oldProps;
+              if (void 0 === observedBits || null === observedBits)
-            0 !== (updateQueue & oldProps) &&
+                observedBits = 1073741823;
-              propagateContextChange(
+              workInProgress.stateNode = observedBits;
-                workInProgress,
+              if (0 !== (changedBits & observedBits))
-                fn,
+                propagateContextChange(
-                updateQueue,
+                  workInProgress,
-                renderExpirationTime
+                  fn,
-              );
+                  changedBits,
-            renderExpirationTime = unmaskedContext.children;
+                  renderExpirationTime
-            renderExpirationTime = renderExpirationTime(props);
+                );
-            reconcileChildren(current, workInProgress, renderExpirationTime);
+              else if (updateQueue === unmaskedContext) {
-            current = workInProgress.child;
+                current = bailoutOnAlreadyFinishedWork(current, workInProgress);
-          } else
+                break a;
-            current = bailoutOnAlreadyFinishedWork(current, workInProgress);
+              }
+              renderExpirationTime = unmaskedContext.children;
+              renderExpirationTime = renderExpirationTime(props);
+              reconcileChildren(current, workInProgress, renderExpirationTime);
+              current = workInProgress.child;
+            } else
+              current = bailoutOnAlreadyFinishedWork(current, workInProgress);
+          }
           return current;
         default:
           invariant(

Libraries/Renderer/ReactNativeRenderer-dev.js

@@ -2995,6 +2995,75 @@ var TouchHistoryMath = {
 
 var ReactVersion = "16.3.1";
 
+var describeComponentFrame = function(name, source, ownerName) {
+  return (
+    "\n    in " +
+    (name || "Unknown") +
+    (source
+      ? " (at " +
+        source.fileName.replace(/^.*[\\\/]/, "") +
+        ":" +
+        source.lineNumber +
+        ")"
+      : ownerName ? " (created by " + ownerName + ")" : "")
+  );
+};
+
+function getComponentName(fiber) {
+  var type = fiber.type;
+
+  if (typeof type === "function") {
+    return type.displayName || type.name;
+  }
+  if (typeof type === "string") {
+    return type;
+  }
+  switch (type) {
+    case REACT_FRAGMENT_TYPE:
+      return "ReactFragment";
+    case REACT_PORTAL_TYPE:
+      return "ReactPortal";
+    case REACT_CALL_TYPE:
+      return "ReactCall";
+    case REACT_RETURN_TYPE:
+      return "ReactReturn";
+  }
+  return null;
+}
+
+function describeFiber(fiber) {
+  switch (fiber.tag) {
+    case IndeterminateComponent:
+    case FunctionalComponent:
+    case ClassComponent:
+    case HostComponent:
+      var owner = fiber._debugOwner;
+      var source = fiber._debugSource;
+      var name = getComponentName(fiber);
+      var ownerName = null;
+      if (owner) {
+        ownerName = getComponentName(owner);
+      }
+      return describeComponentFrame(name, source, ownerName);
+    default:
+      return "";
+  }
+}
+
+// This function can only be called with a work-in-progress fiber and
+// only during begin or complete phase. Do not call it under any other
+// circumstances.
+function getStackAddendumByWorkInProgressFiber(workInProgress) {
+  var info = "";
+  var node = workInProgress;
+  do {
+    info += describeFiber(node);
+    // Otherwise this return pointer might point to the wrong tree:
+    node = node["return"];
+  } while (node);
+  return info;
+}
+
 function _classCallCheck(instance, Constructor) {
   if (!(instance instanceof Constructor)) {
     throw new TypeError("Cannot call a class as a function");
@@ -3589,28 +3658,6 @@ var ReactInternals = React.__SECRET_INTERNALS_DO_NOT_USE_OR_YOU_WILL_BE_FIRED;
 var ReactCurrentOwner = ReactInternals.ReactCurrentOwner;
 var ReactDebugCurrentFrame = ReactInternals.ReactDebugCurrentFrame;
 
-function getComponentName(fiber) {
-  var type = fiber.type;
-
-  if (typeof type === "function") {
-    return type.displayName || type.name;
-  }
-  if (typeof type === "string") {
-    return type;
-  }
-  switch (type) {
-    case REACT_FRAGMENT_TYPE:
-      return "ReactFragment";
-    case REACT_PORTAL_TYPE:
-      return "ReactPortal";
-    case REACT_CALL_TYPE:
-      return "ReactCall";
-    case REACT_RETURN_TYPE:
-      return "ReactReturn";
-  }
-  return null;
-}
-
 // TODO: Share this module between Fabric and React Native renderers
 // so that both can be used in the same tree.
 
@@ -4878,53 +4925,6 @@ function onCommitUnmount(fiber) {
   }
 }
 
-var describeComponentFrame = function(name, source, ownerName) {
-  return (
-    "\n    in " +
-    (name || "Unknown") +
-    (source
-      ? " (at " +
-        source.fileName.replace(/^.*[\\\/]/, "") +
-        ":" +
-        source.lineNumber +
-        ")"
-      : ownerName ? " (created by " + ownerName + ")" : "")
-  );
-};
-
-function describeFiber(fiber) {
-  switch (fiber.tag) {
-    case IndeterminateComponent:
-    case FunctionalComponent:
-    case ClassComponent:
-    case HostComponent:
-      var owner = fiber._debugOwner;
-      var source = fiber._debugSource;
-      var name = getComponentName(fiber);
-      var ownerName = null;
-      if (owner) {
-        ownerName = getComponentName(owner);
-      }
-      return describeComponentFrame(name, source, ownerName);
-    default:
-      return "";
-  }
-}
-
-// This function can only be called with a work-in-progress fiber and
-// only during begin or complete phase. Do not call it under any other
-// circumstances.
-function getStackAddendumByWorkInProgressFiber(workInProgress) {
-  var info = "";
-  var node = workInProgress;
-  do {
-    info += describeFiber(node);
-    // Otherwise this return pointer might point to the wrong tree:
-    node = node["return"];
-  } while (node);
-  return info;
-}
-
 /**
  * Forked from fbjs/warning:
  * https://github.com/facebook/fbjs/blob/e66ba20ad5be433eb54423f2b097d829324d9de6/packages/fbjs/src/__forks__/warning.js
@@ -5019,6 +5019,14 @@ var ReactStrictModeWarnings = {
   var didWarnAboutDeprecatedLifecycles = new Set();
   var didWarnAboutUnsafeLifecycles = new Set();
 
+  var setToSortedString = function(set) {
+    var array = [];
+    set.forEach(function(value) {
+      array.push(value);
+    });
+    return array.sort().join(", ");
+  };
+
   ReactStrictModeWarnings.discardPendingWarnings = function() {
     pendingComponentWillMountWarnings = [];
     pendingComponentWillReceivePropsWarnings = [];
@@ -5044,9 +5052,7 @@ var ReactStrictModeWarnings = {
 
           var formatted = lifecycle.replace("UNSAFE_", "");
           var suggestion = LIFECYCLE_SUGGESTIONS[lifecycle];
-          var sortedComponentNames = Array.from(componentNames)
+          var sortedComponentNames = setToSortedString(componentNames);
-            .sort()
-            .join(", ");
 
           lifecyclesWarningMesages.push(
             formatted +
@@ -5098,9 +5104,7 @@ var ReactStrictModeWarnings = {
         didWarnAboutDeprecatedLifecycles.add(fiber.type);
       });
 
-      var sortedNames = Array.from(uniqueNames)
+      var sortedNames = setToSortedString(uniqueNames);
-        .sort()
-        .join(", ");
 
       lowPriorityWarning$1(
         false,
@@ -5123,9 +5127,7 @@ var ReactStrictModeWarnings = {
         didWarnAboutDeprecatedLifecycles.add(fiber.type);
       });
 
-      var _sortedNames = Array.from(_uniqueNames)
+      var _sortedNames = setToSortedString(_uniqueNames);
-        .sort()
-        .join(", ");
 
       lowPriorityWarning$1(
         false,
@@ -5147,9 +5149,7 @@ var ReactStrictModeWarnings = {
         didWarnAboutDeprecatedLifecycles.add(fiber.type);
       });
 
-      var _sortedNames2 = Array.from(_uniqueNames2)
+      var _sortedNames2 = setToSortedString(_uniqueNames2);
-        .sort()
-        .join(", ");
 
       lowPriorityWarning$1(
         false,
@@ -6475,7 +6475,6 @@ var ReactFiberClassComponent = function(
       if (
         typeof instance.getSnapshotBeforeUpdate === "function" &&
         typeof instance.componentDidUpdate !== "function" &&
-        typeof instance.componentDidUpdate !== "function" &&
         !didWarnAboutGetSnapshotBeforeUpdateWithoutDidUpdate.has(type)
       ) {
         didWarnAboutGetSnapshotBeforeUpdateWithoutDidUpdate.add(type);
@@ -9457,6 +9456,10 @@ var ReactFiberBeginWork = function(
         changedBits,
         renderExpirationTime
       );
+    } else if (oldProps === newProps) {
+      // Skip over a memoized parent with a bitmask bailout even
+      // if we began working on it because of a deeper matching child.
+      return bailoutOnAlreadyFinishedWork(current, workInProgress);
     }
     // There is no bailout on `children` equality because we expect people
     // to often pass a bound method as a child, but it may reference
@@ -14707,6 +14710,14 @@ injectFindHostInstance(NativeRenderer.findHostInstance);
 
 injection$2.injectRenderer(NativeRenderer);
 
+function computeComponentStackForErrorReporting(reactTag) {
+  var fiber = getInstanceFromTag(reactTag);
+  if (!fiber) {
+    return "";
+  }
+  return getStackAddendumByWorkInProgressFiber(fiber);
+}
+
 var roots = new Map();
 
 var ReactNativeRenderer = {
@@ -14762,7 +14773,8 @@ var ReactNativeRenderer = {
     ReactNativePropRegistry: ReactNativePropRegistry, // flattenStyle, Stylesheet
     TouchHistoryMath: TouchHistoryMath, // PanResponder
     createReactNativeComponentClass: createReactNativeComponentClass, // RCTText, RCTView, ReactNativeART
-    takeSnapshot: takeSnapshot
+    takeSnapshot: takeSnapshot, // react-native-implementation
+    computeComponentStackForErrorReporting: computeComponentStackForErrorReporting
   }
 };
 

Libraries/Renderer/ReactNativeRenderer-prod.js

@@ -1198,107 +1198,152 @@ function createPortal(children, containerInfo, implementation) {
   };
 }
 var TouchHistoryMath = {
-    centroidDimension: function(
+  centroidDimension: function(
-      touchHistory,
+    touchHistory,
-      touchesChangedAfter,
+    touchesChangedAfter,
-      isXAxis,
+    isXAxis,
-      ofCurrent
+    ofCurrent
-    ) {
+  ) {
-      var touchBank = touchHistory.touchBank,
+    var touchBank = touchHistory.touchBank,
-        total = 0,
+      total = 0,
-        count = 0;
+      count = 0;
-      touchHistory =
+    touchHistory =
-        1 === touchHistory.numberActiveTouches
+      1 === touchHistory.numberActiveTouches
-          ? touchHistory.touchBank[touchHistory.indexOfSingleActiveTouch]
+        ? touchHistory.touchBank[touchHistory.indexOfSingleActiveTouch]
-          : null;
+        : null;
-      if (null !== touchHistory)
+    if (null !== touchHistory)
-        touchHistory.touchActive &&
+      touchHistory.touchActive &&
-          touchHistory.currentTimeStamp > touchesChangedAfter &&
+        touchHistory.currentTimeStamp > touchesChangedAfter &&
+        ((total +=
+          ofCurrent && isXAxis
+            ? touchHistory.currentPageX
+            : ofCurrent && !isXAxis
+              ? touchHistory.currentPageY
+              : !ofCurrent && isXAxis
+                ? touchHistory.previousPageX
+                : touchHistory.previousPageY),
+        (count = 1));
+    else
+      for (touchHistory = 0; touchHistory < touchBank.length; touchHistory++) {
+        var touchTrack = touchBank[touchHistory];
+        null !== touchTrack &&
+          void 0 !== touchTrack &&
+          touchTrack.touchActive &&
+          touchTrack.currentTimeStamp >= touchesChangedAfter &&
           ((total +=
             ofCurrent && isXAxis
-              ? touchHistory.currentPageX
+              ? touchTrack.currentPageX
               : ofCurrent && !isXAxis
-                ? touchHistory.currentPageY
+                ? touchTrack.currentPageY
                 : !ofCurrent && isXAxis
-                  ? touchHistory.previousPageX
+                  ? touchTrack.previousPageX
-                  : touchHistory.previousPageY),
+                  : touchTrack.previousPageY),
-          (count = 1));
+          count++);
-      else
+      }
-        for (
+    return 0 < count ? total / count : TouchHistoryMath.noCentroid;
-          touchHistory = 0;
-          touchHistory < touchBank.length;
-          touchHistory++
-        ) {
-          var touchTrack = touchBank[touchHistory];
-          null !== touchTrack &&
-            void 0 !== touchTrack &&
-            touchTrack.touchActive &&
-            touchTrack.currentTimeStamp >= touchesChangedAfter &&
-            ((total +=
-              ofCurrent && isXAxis
-                ? touchTrack.currentPageX
-                : ofCurrent && !isXAxis
-                  ? touchTrack.currentPageY
-                  : !ofCurrent && isXAxis
-                    ? touchTrack.previousPageX
-                    : touchTrack.previousPageY),
-            count++);
-        }
-      return 0 < count ? total / count : TouchHistoryMath.noCentroid;
-    },
-    currentCentroidXOfTouchesChangedAfter: function(
-      touchHistory,
-      touchesChangedAfter
-    ) {
-      return TouchHistoryMath.centroidDimension(
-        touchHistory,
-        touchesChangedAfter,
-        !0,
-        !0
-      );
-    },
-    currentCentroidYOfTouchesChangedAfter: function(
-      touchHistory,
-      touchesChangedAfter
-    ) {
-      return TouchHistoryMath.centroidDimension(
-        touchHistory,
-        touchesChangedAfter,
-        !1,
-        !0
-      );
-    },
-    previousCentroidXOfTouchesChangedAfter: function(
-      touchHistory,
-      touchesChangedAfter
-    ) {
-      return TouchHistoryMath.centroidDimension(
-        touchHistory,
-        touchesChangedAfter,
-        !0,
-        !1
-      );
-    },
-    previousCentroidYOfTouchesChangedAfter: function(
-      touchHistory,
-      touchesChangedAfter
-    ) {
-      return TouchHistoryMath.centroidDimension(
-        touchHistory,
-        touchesChangedAfter,
-        !1,
-        !1
-      );
-    },
-    currentCentroidX: function(touchHistory) {
-      return TouchHistoryMath.centroidDimension(touchHistory, 0, !0, !0);
-    },
-    currentCentroidY: function(touchHistory) {
-      return TouchHistoryMath.centroidDimension(touchHistory, 0, !1, !0);
-    },
-    noCentroid: -1
   },
-  objects = {},
+  currentCentroidXOfTouchesChangedAfter: function(
+    touchHistory,
+    touchesChangedAfter
+  ) {
+    return TouchHistoryMath.centroidDimension(
+      touchHistory,
+      touchesChangedAfter,
+      !0,
+      !0
+    );
+  },
+  currentCentroidYOfTouchesChangedAfter: function(
+    touchHistory,
+    touchesChangedAfter
+  ) {
+    return TouchHistoryMath.centroidDimension(
+      touchHistory,
+      touchesChangedAfter,
+      !1,
+      !0
+    );
+  },
+  previousCentroidXOfTouchesChangedAfter: function(
+    touchHistory,
+    touchesChangedAfter
+  ) {
+    return TouchHistoryMath.centroidDimension(
+      touchHistory,
+      touchesChangedAfter,
+      !0,
+      !1
+    );
+  },
+  previousCentroidYOfTouchesChangedAfter: function(
+    touchHistory,
+    touchesChangedAfter
+  ) {
+    return TouchHistoryMath.centroidDimension(
+      touchHistory,
+      touchesChangedAfter,
+      !1,
+      !1
+    );
+  },
+  currentCentroidX: function(touchHistory) {
+    return TouchHistoryMath.centroidDimension(touchHistory, 0, !0, !0);
+  },
+  currentCentroidY: function(touchHistory) {
+    return TouchHistoryMath.centroidDimension(touchHistory, 0, !1, !0);
+  },
+  noCentroid: -1
+};
+function getComponentName(fiber) {
+  fiber = fiber.type;
+  if ("function" === typeof fiber) return fiber.displayName || fiber.name;
+  if ("string" === typeof fiber) return fiber;
+  switch (fiber) {
+    case REACT_FRAGMENT_TYPE:
+      return "ReactFragment";
+    case REACT_PORTAL_TYPE:
+      return "ReactPortal";
+    case REACT_CALL_TYPE:
+      return "ReactCall";
+    case REACT_RETURN_TYPE:
+      return "ReactReturn";
+  }
+  return null;
+}
+function getStackAddendumByWorkInProgressFiber(workInProgress) {
+  var info = "";
+  do {
+    a: switch (workInProgress.tag) {
+      case 0:
+      case 1:
+      case 2:
+      case 5:
+        var owner = workInProgress._debugOwner,
+          source = workInProgress._debugSource;
+        var JSCompiler_inline_result = getComponentName(workInProgress);
+        var ownerName = null;
+        owner && (ownerName = getComponentName(owner));
+        owner = source;
+        JSCompiler_inline_result =
+          "\n    in " +
+          (JSCompiler_inline_result || "Unknown") +
+          (owner
+            ? " (at " +
+              owner.fileName.replace(/^.*[\\\/]/, "") +
+              ":" +
+              owner.lineNumber +
+              ")"
+            : ownerName ? " (created by " + ownerName + ")" : "");
+        break a;
+      default:
+        JSCompiler_inline_result = "";
+    }
+    info += JSCompiler_inline_result;
+    workInProgress = workInProgress["return"];
+  } while (workInProgress);
+  return info;
+}
+var objects = {},
   uniqueID = 1,
   emptyObject$2 = {},
   ReactNativePropRegistry = (function() {
@@ -1561,22 +1606,6 @@ function mountSafeCallback(context, callback) {
 }
 var ReactCurrentOwner =
   React.__SECRET_INTERNALS_DO_NOT_USE_OR_YOU_WILL_BE_FIRED.ReactCurrentOwner;
-function getComponentName(fiber) {
-  fiber = fiber.type;
-  if ("function" === typeof fiber) return fiber.displayName || fiber.name;
-  if ("string" === typeof fiber) return fiber;
-  switch (fiber) {
-    case REACT_FRAGMENT_TYPE:
-      return "ReactFragment";
-    case REACT_PORTAL_TYPE:
-      return "ReactPortal";
-    case REACT_CALL_TYPE:
-      return "ReactCall";
-    case REACT_RETURN_TYPE:
-      return "ReactReturn";
-  }
-  return null;
-}
 function findHostInstance() {
   return null;
 }
@@ -1988,39 +2017,6 @@ function onCommitRoot(root) {
 function onCommitUnmount(fiber) {
   "function" === typeof onCommitFiberUnmount && onCommitFiberUnmount(fiber);
 }
-function getStackAddendumByWorkInProgressFiber(workInProgress) {
-  var info = "";
-  do {
-    a: switch (workInProgress.tag) {
-      case 0:
-      case 1:
-      case 2:
-      case 5:
-        var owner = workInProgress._debugOwner,
-          source = workInProgress._debugSource;
-        var JSCompiler_inline_result = getComponentName(workInProgress);
-        var ownerName = null;
-        owner && (ownerName = getComponentName(owner));
-        owner = source;
-        JSCompiler_inline_result =
-          "\n    in " +
-          (JSCompiler_inline_result || "Unknown") +
-          (owner
-            ? " (at " +
-              owner.fileName.replace(/^.*[\\\/]/, "") +
-              ":" +
-              owner.lineNumber +
-              ")"
-            : ownerName ? " (created by " + ownerName + ")" : "");
-        break a;
-      default:
-        JSCompiler_inline_result = "";
-    }
-    info += JSCompiler_inline_result;
-    workInProgress = workInProgress["return"];
-  } while (workInProgress);
-  return info;
-}
 var _require = require("ReactFeatureFlags"),
   enableGetDerivedStateFromCatch = _require.enableGetDerivedStateFromCatch,
   debugRenderPhaseSideEffects = _require.debugRenderPhaseSideEffects,
@@ -3926,33 +3922,40 @@ function ReactFiberBeginWork(
             renderExpirationTime
           );
         case 12:
-          fn = workInProgress.type;
+          a: {
-          unmaskedContext = workInProgress.pendingProps;
+            fn = workInProgress.type;
-          var oldProps = workInProgress.memoizedProps;
+            unmaskedContext = workInProgress.pendingProps;
-          props = fn._currentValue;
+            updateQueue = workInProgress.memoizedProps;
-          updateQueue = fn._changedBits;
+            props = fn._currentValue;
-          if (
+            var changedBits = fn._changedBits;
-            hasLegacyContextChanged() ||
+            if (
-            0 !== updateQueue ||
+              hasLegacyContextChanged() ||
-            oldProps !== unmaskedContext
+              0 !== changedBits ||
-          ) {
+              updateQueue !== unmaskedContext
-            workInProgress.memoizedProps = unmaskedContext;
+            ) {
-            oldProps = unmaskedContext.unstable_observedBits;
+              workInProgress.memoizedProps = unmaskedContext;
-            if (void 0 === oldProps || null === oldProps) oldProps = 1073741823;
+              var observedBits = unmaskedContext.unstable_observedBits;
-            workInProgress.stateNode = oldProps;
+              if (void 0 === observedBits || null === observedBits)
-            0 !== (updateQueue & oldProps) &&
+                observedBits = 1073741823;
-              propagateContextChange(
+              workInProgress.stateNode = observedBits;
-                workInProgress,
+              if (0 !== (changedBits & observedBits))
-                fn,
+                propagateContextChange(
-                updateQueue,
+                  workInProgress,
-                renderExpirationTime
+                  fn,
-              );
+                  changedBits,
-            renderExpirationTime = unmaskedContext.children;
+                  renderExpirationTime
-            renderExpirationTime = renderExpirationTime(props);
+                );
-            reconcileChildren(current, workInProgress, renderExpirationTime);
+              else if (updateQueue === unmaskedContext) {
-            current = workInProgress.child;
+                current = bailoutOnAlreadyFinishedWork(current, workInProgress);
-          } else
+                break a;
-            current = bailoutOnAlreadyFinishedWork(current, workInProgress);
+              }
+              renderExpirationTime = unmaskedContext.children;
+              renderExpirationTime = renderExpirationTime(props);
+              reconcileChildren(current, workInProgress, renderExpirationTime);
+              current = workInProgress.child;
+            } else
+              current = bailoutOnAlreadyFinishedWork(current, workInProgress);
+          }
           return current;
         default:
           invariant(
@@ -6554,6 +6557,11 @@ var roots = new Map(),
           "window" !== view &&
           (view = findNumericNodeHandleFiber(view) || "window");
         return UIManager.__takeSnapshot(view, options);
+      },
+      computeComponentStackForErrorReporting: function(reactTag) {
+        return (reactTag = getInstanceFromTag(reactTag))
+          ? getStackAddendumByWorkInProgressFiber(reactTag)
+          : "";
       }
     }
   };