Themes: Add queryRequestErrors reducer and tests

client/state/themes/reducer.js

@@ -211,6 +211,35 @@ export function queryRequests( state = {}, action ) {
 	return state;
 }
 
+/**
+ * Returns the updated query request error state after an action has been
+ * dispatched. The state reflects a mapping of site ID, query ID pairing to an
+ * object containing the request error. If there is no error null is stored.
+ *
+ * @param  {Object} state  Current state
+ * @param  {Object} action Action payload
+ * @return {Object}        Updated state
+ */
+export const queryRequestErrors = createReducer( {}, {
+	[ THEMES_REQUEST_FAILURE ]: ( state, { siteId, query, error } ) => {
+		const serializedQuery = getSerializedThemesQuery( query, siteId );
+		return {
+			...state,
+			[ siteId ]: {
+				...state[ siteId ],
+				[ serializedQuery ]: error
+			}
+		};
+	},
+	[ THEMES_REQUEST_SUCCESS ]: ( state, { siteId, query } ) => {
+		const serializedQuery = getSerializedThemesQuery( query, siteId );
+		return {
+			...state,
+			[ siteId ]: omit( state[ siteId ], serializedQuery ),
+		};
+	}
+} );
+
 /**
  * Returns the updated theme query state after an action has been dispatched.
  * The state reflects a mapping of serialized query key to an array of theme IDs

client/state/themes/test/reducer.js

@@ -27,6 +27,7 @@ import {
 } from 'state/action-types';
 import reducer, {
 	queryRequests,
+	queryRequestErrors,
 	queries,
 	lastQuery,
 	themeRequests,
@@ -181,6 +182,101 @@ describe( 'reducer', () => {
 		} );
 	} );
 
+	describe( '#queryRequestErrors()', () => {
+		it( 'should default to an empty object', () => {
+			const state = queryRequestErrors( undefined, {} );
+
+			expect( state ).to.deep.equal( {} );
+		} );
+
+		it( 'should create empty mapping on success if previous state was empty', () => {
+			const state = queryRequestErrors( deepFreeze( {} ), {
+				type: THEMES_REQUEST_SUCCESS,
+				siteId: 2916284,
+				query: { search: 'Twenty' }
+			} );
+
+			expect( state ).to.deep.equal( {
+				2916284: {}
+			} );
+		} );
+
+		it( 'should map site ID, query to error if request finishes with failure', () => {
+			const state = queryRequestErrors( deepFreeze( {} ), {
+				type: THEMES_REQUEST_FAILURE,
+				siteId: 2916284,
+				query: { search: 'Twenty' },
+				error: 'Request error'
+			} );
+
+			expect( state ).to.deep.equal( {
+				2916284: {
+					'2916284:{"search":"Twenty"}': 'Request error'
+				}
+			} );
+		} );
+
+		it( 'should reset error state after successful request after a failure', () => {
+			const state = queryRequestErrors( deepFreeze( {
+				2916284: {
+					'2916284:{"search":"Twenty"}': 'Request Error'
+				}
+			} ), {
+				type: THEMES_REQUEST_SUCCESS,
+				siteId: 2916284,
+				query: { search: 'Twenty' }
+			} );
+
+			expect( state ).to.deep.equal( {
+				2916284: {}
+			} );
+		} );
+
+		it( 'should accumulate mappings', () => {
+			const state = queryRequestErrors( deepFreeze( {
+				2916284: {
+					'2916284:{"blerch":"Twenty"}': 'Invalid query!'
+				}
+			} ), {
+				type: THEMES_REQUEST_FAILURE,
+				siteId: 2916284,
+				query: { search: 'Twenty' },
+				error: 'System error'
+			} );
+
+			expect( state ).to.deep.equal( {
+				2916284: {
+					'2916284:{"blerch":"Twenty"}': 'Invalid query!',
+					'2916284:{"search":"Twenty"}': 'System error'
+				}
+			} );
+		} );
+
+		it( 'never persists state', () => {
+			const state = queryRequestErrors( deepFreeze( {
+				2916284: {
+					'2916284:{"search":"Twenty"}': null
+				}
+			} ), {
+				type: SERIALIZE
+			} );
+
+			expect( state ).to.deep.equal( {} );
+		} );
+
+		it( 'never loads persisted state', () => {
+			const state = queryRequestErrors( deepFreeze( {
+				2916284: {
+					'2916284:{"search":"Twenty"}': null
+				}
+			} ), {
+				type: DESERIALIZE
+			} );
+
+			expect( state ).to.deep.equal( {} );
+		} );
+	} );
+
 	describe( '#queries()', () => {
 		it( 'should default to an empty object', () => {
 			const state = queries( undefined, {} );
@@ -502,9 +598,7 @@ describe( 'reducer', () => {
 		it( 'should switch from error to no mapping after successful request after a failure', () => {
 			const state = themeRequestErrors( deepFreeze( {
 				2916284: {
-					pinboard: {
-						error: 'Request Error'
-					}
+					pinboard: 'Request Error'
 				}
 			} ), {
 				type: THEME_REQUEST_SUCCESS,