If a more recent revision/autosave exists, store its state on editor setup

docs/designers-developers/developers/data/data-core-editor.md

@@ -193,11 +193,17 @@ saved state of the post.
 
 Post attribute value.
 
-### getAutosaveAttribute
+### getAutosaveAttribute (deprecated)
 
 Returns an attribute value of the current autosave revision for a post, or
 null if there is no autosave for the post.
 
+*Deprecated*
+
+Deprecated since 5.6. Callers should use the `getAutosave( postType, postId, userId )` selector
+			   from the '@wordpress/core-data' package and access properties on the returned
+			   autosave object using getPostRawValue.
+
 *Parameters*
 
  * state: Global application state.
@@ -303,17 +309,23 @@ Returns true if the post can be autosaved, or false otherwise.
 *Parameters*
 
  * state: Global application state.
+ * autosave: A raw autosave object from the REST API.
 
 *Returns*
 
 Whether the post can be autosaved.
 
-### getAutosave
+### getAutosave (deprecated)
 
 Returns the current autosave, or null if one is not set (i.e. if the post
 has yet to be autosaved, or has been saved or published since the last
 autosave).
 
+*Deprecated*
+
+Deprecated since 5.6. Callers should use the `getAutosave( postType, postId, userId )`
+			   selector from the '@wordpress/core-data' package.
+
 *Parameters*
 
  * state: Editor state.
@@ -322,10 +334,15 @@ autosave).
 
 Current autosave, if exists.
 
-### hasAutosave
+### hasAutosave (deprecated)
 
 Returns the true if there is an existing autosave, otherwise false.
 
+*Deprecated*
+
+Deprecated since 5.6. Callers should use the `getAutosave( postType, postId, userId )` selector
+            from the '@wordpress/core-data' package and check for a truthy value.
+
 *Parameters*
 
  * state: Global application state.
@@ -752,14 +769,19 @@ post has been received, either by initialization or save.
 
  * post: Post object.
 
-### resetAutosave
+### resetAutosave (deprecated)
 
 Returns an action object used in signalling that the latest autosave of the
 post has been received, by initialization or autosave.
 
+*Deprecated*
+
+Deprecated since 5.6. Callers should use the `receiveAutosaves( postId, autosave )`
+			   selector from the '@wordpress/core-data' package.
+
 *Parameters*
 
- * post: Autosave post object.
+ * newAutosave: Autosave post object.
 
 ### __experimentalRequestPostUpdateStart
 

docs/designers-developers/developers/data/data-core.md

@@ -24,6 +24,18 @@ Returns all available authors.
 
 Authors list.
 
+### getCurrentUser
+
+Returns the current user.
+
+*Parameters*
+
+ * state: Data state.
+
+*Returns*
+
+Current user object.
+
 ### getUserQueryResults
 
 Returns all the users returned by a query ID.
@@ -181,6 +193,52 @@ https://developer.wordpress.org/rest-api/reference/
 Whether or not the user can perform the action,
                             or `undefined` if the OPTIONS request is still being made.
 
+### getAutosaves
+
+Returns the latest autosaves for the post.
+
+May return multiple autosaves since the backend stores one autosave per
+author for each post.
+
+*Parameters*
+
+ * state: State tree.
+ * postType: The type of the parent post.
+ * postId: The id of the parent post.
+
+*Returns*
+
+An array of autosaves for the post, or undefined if there is none.
+
+### getAutosave
+
+Returns the autosave for the post and author.
+
+*Parameters*
+
+ * state: State tree.
+ * postType: The type of the parent post.
+ * postId: The id of the parent post.
+ * authorId: The id of the author.
+
+*Returns*
+
+The autosave for the post and author.
+
+### hasFetchedAutosaves
+
+Returns true if the REST request for autosaves has completed.
+
+*Parameters*
+
+ * state: State tree.
+ * postType: The type of the parent post.
+ * postId: The id of the parent post.
+
+*Returns*
+
+True if the REST request was completed. False otherwise.
+
 ## Actions
 
 ### receiveUserQuery
@@ -192,6 +250,14 @@ Returns an action object used in signalling that authors have been received.
  * queryID: Query ID.
  * users: Users received.
 
+### receiveCurrentUser
+
+Returns an action used in signalling that the current user has been received.
+
+*Parameters*
+
+ * currentUser: Current user object.
+
 ### addEntities
 
 Returns an action object used in adding new entities.
@@ -256,4 +322,14 @@ permission to perform an action on a REST resource.
 *Parameters*
 
  * key: A key that represents the action and REST resource.
- * isAllowed: Whether or not the user can perform the action.
+ * isAllowed: Whether or not the user can perform the action.
+
+### receiveAutosaves
+
+Returns an action object used in signalling that the autosaves for a
+post have been received.
+
+*Parameters*
+
+ * postId: The id of the post that is parent to the autosave.
+ * autosaves: An array of autosaves or singular autosave object.

packages/core-data/CHANGELOG.md

@@ -1,3 +1,9 @@
+## 2.1.0 (Unreleased)
+
+### New features
+- The `getAutosave`, `getAutosaves` and `getCurrentUser` selectors have been added.
+- The `receiveAutosaves` and `receiveCurrentUser` actions have been added.
+
 ## 2.0.16 (2019-01-03)
 
 ### Bug Fixes

packages/core-data/src/actions.js

@@ -29,6 +29,20 @@ export function receiveUserQuery( queryID, users ) {
 	};
 }
 
+/**
+ * Returns an action used in signalling that the current user has been received.
+ *
+ * @param {Object} currentUser Current user object.
+ *
+ * @return {Object} Action object.
+ */
+export function receiveCurrentUser( currentUser ) {
+	return {
+		type: 'RECEIVE_CURRENT_USER',
+		currentUser,
+	};
+}
+
 /**
  * Returns an action object used in adding new entities.
  *
@@ -159,3 +173,20 @@ export function receiveUserPermission( key, isAllowed ) {
 		isAllowed,
 	};
 }
+
+/**
+ * Returns an action object used in signalling that the autosaves for a
+ * post have been received.
+ *
+ * @param {number}       postId    The id of the post that is parent to the autosave.
+ * @param {Array|Object} autosaves An array of autosaves or singular autosave object.
+ *
+ * @return {Object} Action object.
+ */
+export function receiveAutosaves( postId, autosaves ) {
+	return {
+		type: 'RECEIVE_AUTOSAVES',
+		postId,
+		autosaves: castArray( autosaves ),
+	};
+}

packages/core-data/src/controls.js

@@ -32,6 +32,23 @@ export function select( selectorName, ...args ) {
 	};
 }
 
+/**
+ * Dispatches a control action for triggering a registry select that has a
+ * resolver.
+ *
+ * @param {string}  selectorName
+ * @param {Array}   args  Arguments for the select.
+ *
+ * @return {Object} control descriptor.
+ */
+export function resolveSelect( selectorName, ...args ) {
+	return {
+		type: 'RESOLVE_SELECT',
+		selectorName,
+		args,
+	};
+}
+
 const controls = {
 	API_FETCH( { request } ) {
 		return triggerApiFetch( request );
@@ -40,6 +57,30 @@ const controls = {
 	SELECT: createRegistryControl( ( registry ) => ( { selectorName, args } ) => {
 		return registry.select( 'core' )[ selectorName ]( ...args );
 	} ),
+
+	RESOLVE_SELECT: createRegistryControl(
+		( registry ) => ( { selectorName, args } ) => {
+			return new Promise( ( resolve ) => {
+				const hasFinished = () => registry.select( 'core/data' )
+					.hasFinishedResolution( 'core', selectorName, args );
+				const getResult = () => registry.select( 'core' )[ selectorName ]
+					.apply( null, args );
+
+				// trigger the selector (to trigger the resolver)
+				const result = getResult();
+				if ( hasFinished() ) {
+					return resolve( result );
+				}
+
+				const unsubscribe = registry.subscribe( () => {
+					if ( hasFinished() ) {
+						unsubscribe();
+						resolve( getResult() );
+					}
+				} );
+			} );
+		}
+	),
 };
 
 export default controls;

packages/core-data/src/reducer.js

@@ -64,6 +64,23 @@ export function users( state = { byId: {}, queries: {} }, action ) {
 	return state;
 }
 
+/**
+ * Reducer managing current user state.
+ *
+ * @param {Object} state  Current state.
+ * @param {Object} action Dispatched action.
+ *
+ * @return {Object} Updated state.
+ */
+export function currentUser( state = {}, action ) {
+	switch ( action.type ) {
+		case 'RECEIVE_CURRENT_USER':
+			return action.currentUser;
+	}
+
+	return state;
+}
+
 /**
  * Reducer managing taxonomies.
  *
@@ -238,12 +255,36 @@ export function userPermissions( state = {}, action ) {
 	return state;
 }
 
+/**
+ * Reducer returning autosaves keyed by their parent's post id.
+ *
+ * @param  {Object} state  Current state.
+ * @param  {Object} action Dispatched action.
+ *
+ * @return {Object} Updated state.
+ */
+export function autosaves( state = {}, action ) {
+	switch ( action.type ) {
+		case 'RECEIVE_AUTOSAVES':
+			const { postId, autosaves: autosavesData } = action;
+
+			return {
+				...state,
+				[ postId ]: autosavesData,
+			};
+	}
+
+	return state;
+}
+
 export default combineReducers( {
 	terms,
 	users,
+	currentUser,
 	taxonomies,
 	themeSupports,
 	entities,
 	embedPreviews,
 	userPermissions,
+	autosaves,
 } );