Forked ComponentStackFrame and FiberComponentStack into DevTools

Author: Brian Vaughn

packages/react-devtools-shared/src/backend/DevToolsComponentStackFrame.js

@@ -0,0 +1,298 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow
+ */
+
+// This is a DevTools fork of ReactComponentStackFrame.
+// This fork enables DevTools to use the same "native" component stack format,
+// while still maintaining support for multiple renderer versions
+// (which use different values for ReactTypeOfWork).
+
+import type {Source} from 'shared/ReactElementType';
+import type {LazyComponent} from 'react/src/ReactLazy';
+import type {CurrentDispatcherRef} from './types';
+
+import {
+  BLOCK_NUMBER,
+  BLOCK_SYMBOL_STRING,
+  FORWARD_REF_NUMBER,
+  FORWARD_REF_SYMBOL_STRING,
+  LAZY_NUMBER,
+  LAZY_SYMBOL_STRING,
+  MEMO_NUMBER,
+  MEMO_SYMBOL_STRING,
+  SUSPENSE_NUMBER,
+  SUSPENSE_SYMBOL_STRING,
+  SUSPENSE_LIST_NUMBER,
+  SUSPENSE_LIST_SYMBOL_STRING,
+} from './ReactSymbols';
+
+// These methods are safe to import from shared;
+// there is no React-specific logic here.
+import {disableLogs, reenableLogs} from 'shared/ConsolePatchingDev';
+
+let prefix;
+export function describeBuiltInComponentFrame(
+  name: string,
+  source: void | null | Source,
+  ownerFn: void | null | Function,
+): string {
+  if (prefix === undefined) {
+    // Extract the VM specific prefix used by each line.
+    try {
+      throw Error();
+    } catch (x) {
+      const match = x.stack.trim().match(/\n( *(at )?)/);
+      prefix = (match && match[1]) || '';
+    }
+  }
+  // We use the prefix to ensure our stacks line up with native stack frames.
+  return '\n' + prefix + name;
+}
+
+let reentry = false;
+let componentFrameCache;
+if (__DEV__) {
+  const PossiblyWeakMap = typeof WeakMap === 'function' ? WeakMap : Map;
+  componentFrameCache = new PossiblyWeakMap();
+}
+
+export function describeNativeComponentFrame(
+  fn: Function,
+  construct: boolean,
+  currentDispatcherRef: CurrentDispatcherRef,
+): string {
+  // If something asked for a stack inside a fake render, it should get ignored.
+  if (!fn || reentry) {
+    return '';
+  }
+
+  if (__DEV__) {
+    const frame = componentFrameCache.get(fn);
+    if (frame !== undefined) {
+      return frame;
+    }
+  }
+
+  let control;
+
+  reentry = true;
+  let previousDispatcher;
+  if (__DEV__) {
+    previousDispatcher = currentDispatcherRef.current;
+    // Set the dispatcher in DEV because this might be call in the render function
+    // for warnings.
+    currentDispatcherRef.current = null;
+    disableLogs();
+  }
+  try {
+    // This should throw.
+    if (construct) {
+      // Something should be setting the props in the constructor.
+      const Fake = function() {
+        throw Error();
+      };
+      // $FlowFixMe
+      Object.defineProperty(Fake.prototype, 'props', {
+        set: function() {
+          // We use a throwing setter instead of frozen or non-writable props
+          // because that won't throw in a non-strict mode function.
+          throw Error();
+        },
+      });
+      if (typeof Reflect === 'object' && Reflect.construct) {
+        // We construct a different control for this case to include any extra
+        // frames added by the construct call.
+        try {
+          Reflect.construct(Fake, []);
+        } catch (x) {
+          control = x;
+        }
+        Reflect.construct(fn, [], Fake);
+      } else {
+        try {
+          Fake.call();
+        } catch (x) {
+          control = x;
+        }
+        fn.call(Fake.prototype);
+      }
+    } else {
+      try {
+        throw Error();
+      } catch (x) {
+        control = x;
+      }
+      fn();
+    }
+  } catch (sample) {
+    // This is inlined manually because closure doesn't do it for us.
+    if (sample && control && typeof sample.stack === 'string') {
+      // This extracts the first frame from the sample that isn't also in the control.
+      // Skipping one frame that we assume is the frame that calls the two.
+      const sampleLines = sample.stack.split('\n');
+      const controlLines = control.stack.split('\n');
+      let s = sampleLines.length - 1;
+      let c = controlLines.length - 1;
+      while (s >= 1 && c >= 0 && sampleLines[s] !== controlLines[c]) {
+        // We expect at least one stack frame to be shared.
+        // Typically this will be the root most one. However, stack frames may be
+        // cut off due to maximum stack limits. In this case, one maybe cut off
+        // earlier than the other. We assume that the sample is longer or the same
+        // and there for cut off earlier. So we should find the root most frame in
+        // the sample somewhere in the control.
+        c--;
+      }
+      for (; s >= 1 && c >= 0; s--, c--) {
+        // Next we find the first one that isn't the same which should be the
+        // frame that called our sample function and the control.
+        if (sampleLines[s] !== controlLines[c]) {
+          // In V8, the first line is describing the message but other VMs don't.
+          // If we're about to return the first line, and the control is also on the same
+          // line, that's a pretty good indicator that our sample threw at same line as
+          // the control. I.e. before we entered the sample frame. So we ignore this result.
+          // This can happen if you passed a class to function component, or non-function.
+          if (s !== 1 || c !== 1) {
+            do {
+              s--;
+              c--;
+              // We may still have similar intermediate frames from the construct call.
+              // The next one that isn't the same should be our match though.
+              if (c < 0 || sampleLines[s] !== controlLines[c]) {
+                // V8 adds a "new" prefix for native classes. Let's remove it to make it prettier.
+                const frame = '\n' + sampleLines[s].replace(' at new ', ' at ');
+                if (__DEV__) {
+                  if (typeof fn === 'function') {
+                    componentFrameCache.set(fn, frame);
+                  }
+                }
+                // Return the line we found.
+                return frame;
+              }
+            } while (s >= 1 && c >= 0);
+          }
+          break;
+        }
+      }
+    }
+  } finally {
+    reentry = false;
+    if (__DEV__) {
+      currentDispatcherRef.current = previousDispatcher;
+      reenableLogs();
+    }
+  }
+  // Fallback to just using the name if we couldn't make it throw.
+  const name = fn ? fn.displayName || fn.name : '';
+  const syntheticFrame = name ? describeBuiltInComponentFrame(name) : '';
+  if (__DEV__) {
+    if (typeof fn === 'function') {
+      componentFrameCache.set(fn, syntheticFrame);
+    }
+  }
+  return syntheticFrame;
+}
+
+export function describeClassComponentFrame(
+  ctor: Function,
+  source: void | null | Source,
+  ownerFn: void | null | Function,
+  currentDispatcherRef: CurrentDispatcherRef,
+): string {
+  return describeNativeComponentFrame(ctor, true, currentDispatcherRef);
+}
+
+export function describeFunctionComponentFrame(
+  fn: Function,
+  source: void | null | Source,
+  ownerFn: void | null | Function,
+  currentDispatcherRef: CurrentDispatcherRef,
+): string {
+  return describeNativeComponentFrame(fn, false, currentDispatcherRef);
+}
+
+function shouldConstruct(Component: Function) {
+  const prototype = Component.prototype;
+  return !!(prototype && prototype.isReactComponent);
+}
+
+export function describeUnknownElementTypeFrameInDEV(
+  type: any,
+  source: void | null | Source,
+  ownerFn: void | null | Function,
+  currentDispatcherRef: CurrentDispatcherRef,
+): string {
+  if (!__DEV__) {
+    return '';
+  }
+  if (type == null) {
+    return '';
+  }
+  if (typeof type === 'function') {
+    return describeNativeComponentFrame(
+      type,
+      shouldConstruct(type),
+      currentDispatcherRef,
+    );
+  }
+  if (typeof type === 'string') {
+    return describeBuiltInComponentFrame(type, source, ownerFn);
+  }
+  switch (type) {
+    case SUSPENSE_NUMBER:
+    case SUSPENSE_SYMBOL_STRING:
+      return describeBuiltInComponentFrame('Suspense', source, ownerFn);
+    case SUSPENSE_LIST_NUMBER:
+    case SUSPENSE_LIST_SYMBOL_STRING:
+      return describeBuiltInComponentFrame('SuspenseList', source, ownerFn);
+  }
+  if (typeof type === 'object') {
+    switch (type.$$typeof) {
+      case FORWARD_REF_NUMBER:
+      case FORWARD_REF_SYMBOL_STRING:
+        return describeFunctionComponentFrame(
+          type.render,
+          source,
+          ownerFn,
+          currentDispatcherRef,
+        );
+      case MEMO_NUMBER:
+      case MEMO_SYMBOL_STRING:
+        // Memo may contain any component type so we recursively resolve it.
+        return describeUnknownElementTypeFrameInDEV(
+          type.type,
+          source,
+          ownerFn,
+          currentDispatcherRef,
+        );
+      case BLOCK_NUMBER:
+      case BLOCK_SYMBOL_STRING:
+        return describeFunctionComponentFrame(
+          type._render,
+          source,
+          ownerFn,
+          currentDispatcherRef,
+        );
+      case LAZY_NUMBER:
+      case LAZY_SYMBOL_STRING: {
+        const lazyComponent: LazyComponent<any, any> = (type: any);
+        const payload = lazyComponent._payload;
+        const init = lazyComponent._init;
+        try {
+          // Lazy may contain any component type so we recursively resolve it.
+          return describeUnknownElementTypeFrameInDEV(
+            init(payload),
+            source,
+            ownerFn,
+            currentDispatcherRef,
+          );
+        } catch (x) {}
+      }
+    }
+  }
+  return '';
+}