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Diffstat (limited to 'node_modules/react-dom/lib/ReactDOMComponentTree.js')
-rw-r--r-- | node_modules/react-dom/lib/ReactDOMComponentTree.js | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/node_modules/react-dom/lib/ReactDOMComponentTree.js b/node_modules/react-dom/lib/ReactDOMComponentTree.js new file mode 100644 index 000000000..2b34ddf73 --- /dev/null +++ b/node_modules/react-dom/lib/ReactDOMComponentTree.js @@ -0,0 +1,194 @@ +/** + * Copyright 2013-present, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of this source tree. An additional grant + * of patent rights can be found in the PATENTS file in the same directory. + * + */ + +'use strict'; + +var _prodInvariant = require('./reactProdInvariant'); + +var DOMProperty = require('./DOMProperty'); +var ReactDOMComponentFlags = require('./ReactDOMComponentFlags'); + +var invariant = require('fbjs/lib/invariant'); + +var ATTR_NAME = DOMProperty.ID_ATTRIBUTE_NAME; +var Flags = ReactDOMComponentFlags; + +var internalInstanceKey = '__reactInternalInstance$' + Math.random().toString(36).slice(2); + +/** + * Check if a given node should be cached. + */ +function shouldPrecacheNode(node, nodeID) { + return node.nodeType === 1 && node.getAttribute(ATTR_NAME) === String(nodeID) || node.nodeType === 8 && node.nodeValue === ' react-text: ' + nodeID + ' ' || node.nodeType === 8 && node.nodeValue === ' react-empty: ' + nodeID + ' '; +} + +/** + * Drill down (through composites and empty components) until we get a host or + * host text component. + * + * This is pretty polymorphic but unavoidable with the current structure we have + * for `_renderedChildren`. + */ +function getRenderedHostOrTextFromComponent(component) { + var rendered; + while (rendered = component._renderedComponent) { + component = rendered; + } + return component; +} + +/** + * Populate `_hostNode` on the rendered host/text component with the given + * DOM node. The passed `inst` can be a composite. + */ +function precacheNode(inst, node) { + var hostInst = getRenderedHostOrTextFromComponent(inst); + hostInst._hostNode = node; + node[internalInstanceKey] = hostInst; +} + +function uncacheNode(inst) { + var node = inst._hostNode; + if (node) { + delete node[internalInstanceKey]; + inst._hostNode = null; + } +} + +/** + * Populate `_hostNode` on each child of `inst`, assuming that the children + * match up with the DOM (element) children of `node`. + * + * We cache entire levels at once to avoid an n^2 problem where we access the + * children of a node sequentially and have to walk from the start to our target + * node every time. + * + * Since we update `_renderedChildren` and the actual DOM at (slightly) + * different times, we could race here and see a newer `_renderedChildren` than + * the DOM nodes we see. To avoid this, ReactMultiChild calls + * `prepareToManageChildren` before we change `_renderedChildren`, at which + * time the container's child nodes are always cached (until it unmounts). + */ +function precacheChildNodes(inst, node) { + if (inst._flags & Flags.hasCachedChildNodes) { + return; + } + var children = inst._renderedChildren; + var childNode = node.firstChild; + outer: for (var name in children) { + if (!children.hasOwnProperty(name)) { + continue; + } + var childInst = children[name]; + var childID = getRenderedHostOrTextFromComponent(childInst)._domID; + if (childID === 0) { + // We're currently unmounting this child in ReactMultiChild; skip it. + continue; + } + // We assume the child nodes are in the same order as the child instances. + for (; childNode !== null; childNode = childNode.nextSibling) { + if (shouldPrecacheNode(childNode, childID)) { + precacheNode(childInst, childNode); + continue outer; + } + } + // We reached the end of the DOM children without finding an ID match. + !false ? process.env.NODE_ENV !== 'production' ? invariant(false, 'Unable to find element with ID %s.', childID) : _prodInvariant('32', childID) : void 0; + } + inst._flags |= Flags.hasCachedChildNodes; +} + +/** + * Given a DOM node, return the closest ReactDOMComponent or + * ReactDOMTextComponent instance ancestor. + */ +function getClosestInstanceFromNode(node) { + if (node[internalInstanceKey]) { + return node[internalInstanceKey]; + } + + // Walk up the tree until we find an ancestor whose instance we have cached. + var parents = []; + while (!node[internalInstanceKey]) { + parents.push(node); + if (node.parentNode) { + node = node.parentNode; + } else { + // Top of the tree. This node must not be part of a React tree (or is + // unmounted, potentially). + return null; + } + } + + var closest; + var inst; + for (; node && (inst = node[internalInstanceKey]); node = parents.pop()) { + closest = inst; + if (parents.length) { + precacheChildNodes(inst, node); + } + } + + return closest; +} + +/** + * Given a DOM node, return the ReactDOMComponent or ReactDOMTextComponent + * instance, or null if the node was not rendered by this React. + */ +function getInstanceFromNode(node) { + var inst = getClosestInstanceFromNode(node); + if (inst != null && inst._hostNode === node) { + return inst; + } else { + return null; + } +} + +/** + * Given a ReactDOMComponent or ReactDOMTextComponent, return the corresponding + * DOM node. + */ +function getNodeFromInstance(inst) { + // Without this first invariant, passing a non-DOM-component triggers the next + // invariant for a missing parent, which is super confusing. + !(inst._hostNode !== undefined) ? process.env.NODE_ENV !== 'production' ? invariant(false, 'getNodeFromInstance: Invalid argument.') : _prodInvariant('33') : void 0; + + if (inst._hostNode) { + return inst._hostNode; + } + + // Walk up the tree until we find an ancestor whose DOM node we have cached. + var parents = []; + while (!inst._hostNode) { + parents.push(inst); + !inst._hostParent ? process.env.NODE_ENV !== 'production' ? invariant(false, 'React DOM tree root should always have a node reference.') : _prodInvariant('34') : void 0; + inst = inst._hostParent; + } + + // Now parents contains each ancestor that does *not* have a cached native + // node, and `inst` is the deepest ancestor that does. + for (; parents.length; inst = parents.pop()) { + precacheChildNodes(inst, inst._hostNode); + } + + return inst._hostNode; +} + +var ReactDOMComponentTree = { + getClosestInstanceFromNode: getClosestInstanceFromNode, + getInstanceFromNode: getInstanceFromNode, + getNodeFromInstance: getNodeFromInstance, + precacheChildNodes: precacheChildNodes, + precacheNode: precacheNode, + uncacheNode: uncacheNode +}; + +module.exports = ReactDOMComponentTree;
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