Delete flattenChildren (#10224)

* Delete flattenChildren

* Stop exporting mapIntoWithKeyPrefixInternal

* Remove unescapeInDev()

flattenChildren() was the only traverseAllChildren() caller that relied on it.

src/isomorphic/children/ReactChildren.js

@@ -201,7 +201,6 @@ function toArray(children) {
 var ReactChildren = {
   forEach: forEachChildren,
   map: mapChildren,
-  mapIntoWithKeyPrefixInternal: mapIntoWithKeyPrefixInternal,
   count: countChildren,
   toArray: toArray,
 };

src/isomorphic/children/flattenChildren.js

@@ -1,92 +0,0 @@
-/**
- * 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.
- *
- * @providesModule flattenChildren
- * @flow
- */
-
-'use strict';
-
-var traverseAllChildren = require('traverseAllChildren');
-var ReactComponentTreeHook = require('ReactComponentTreeHook');
-
-if (__DEV__) {
-  var warning = require('fbjs/lib/warning');
-}
-
-/**
- * @param {function} traverseContext Context passed through traversal.
- * @param {?ReactComponent} child React child component.
- * @param {!string} name String name of key path to child.
- * @param {number=} selfDebugID Optional debugID of the current internal instance.
- */
-function flattenSingleChildIntoContext(
-  traverseContext: mixed,
-  child: ReactElement<any>,
-  name: string,
-  selfDebugID?: number,
-  unescapeInDev: (name: string) => string,
-): void {
-  // We found a component instance.
-  if (traverseContext && typeof traverseContext === 'object') {
-    const result = traverseContext;
-    const keyUnique = result[name] === undefined;
-    if (__DEV__) {
-      if (!keyUnique) {
-        warning(
-          false,
-          'flattenChildren(...): Encountered two children with the same key, ' +
-            '`%s`. Keys should be unique so that components maintain their ' +
-            'identity across updates. Non-unique keys may cause children to ' +
-            'be duplicated and/or omitted — the behavior is ' +
-            'unsupported and could change in a future version.%s',
-          unescapeInDev(name),
-          ReactComponentTreeHook.getStackAddendumByID(selfDebugID),
-        );
-      }
-    }
-    if (keyUnique && child != null) {
-      result[name] = child;
-    }
-  }
-}
-
-/**
- * Flattens children that are typically specified as `props.children`. Any null
- * children will not be included in the resulting object.
- * @return {!object} flattened children keyed by name.
- */
-function flattenChildren(
-  children: ReactElement<any>,
-  selfDebugID?: number,
-): ?{[name: string]: ReactElement<any>} {
-  if (children == null) {
-    return children;
-  }
-  var result = {};
-
-  if (__DEV__) {
-    traverseAllChildren(
-      children,
-      (traverseContext, child, name, unescapeInDev) =>
-        flattenSingleChildIntoContext(
-          traverseContext,
-          child,
-          name,
-          selfDebugID,
-          unescapeInDev,
-        ),
-      result,
-    );
-  } else {
-    traverseAllChildren(children, flattenSingleChildIntoContext, result);
-  }
-  return result;
-}
-
-module.exports = flattenChildren;

src/isomorphic/children/traverseAllChildren.js

@@ -11,7 +11,6 @@
 
 'use strict';
 
-var emptyFunction = require('fbjs/lib/emptyFunction');
 var invariant = require('fbjs/lib/invariant');
 
 var ITERATOR_SYMBOL = typeof Symbol === 'function' && Symbol.iterator;
@@ -49,30 +48,6 @@ function escape(key: string): string {
   return '$' + escapedString;
 }
 
-var unescapeInDev = emptyFunction;
-if (__DEV__) {
-  /**
-   * Unescape and unwrap key for human-readable display
-   *
-   * @param {string} key to unescape.
-   * @return {string} the unescaped key.
-   */
-  unescapeInDev = function(key: string): string {
-    var unescapeRegex = /(=0|=2)/g;
-    var unescaperLookup = {
-      '=0': '=',
-      '=2': ':',
-    };
-    var keySubstring = key[0] === '.' && key[1] === '$'
-      ? key.substring(2)
-      : key.substring(1);
-
-    return ('' + keySubstring).replace(unescapeRegex, function(match) {
-      return unescaperLookup[match];
-    });
-  };
-}
-
 /**
  * TODO: Test that a single child and an array with one item have the same key
  * pattern.
@@ -137,7 +112,6 @@ function traverseAllChildrenImpl(
       // If it's the only child, treat the name as if it was wrapped in an array
       // so that it's consistent if the number of children grows.
       nameSoFar === '' ? SEPARATOR + getComponentKey(children, 0) : nameSoFar,
-      unescapeInDev,
     );
     return 1;
   }