feat: add support for keyboard shortcuts

- Implemented most of the keyboard shortcuts specified in stdlib-js#26
- Moved shortcuts prop and related methods to client.jsx
- Made sure to not to overlap with the webaim keyboard shortcuts for web accessibility

public/css/docs/layout.css

@@ -1143,10 +1143,28 @@ h2 {
 	display: flex;
 }
 
+.readme.help h2 {
+	border-bottom: 0px;
+}
+
 .readme.help h1 span {
 	flex-grow: 1;
 }
 
+.readme.help .keyboard-shortcut {
+	display: flex;
+	margin-bottom: 2em;
+	flex-direction: row;
+	align-items: baseline;
+	justify-content: space-between;
+	border-bottom: 2px solid var(--heading-border-bottom-color);
+
+}
+
+.readme.help .keyboard-shortcut-section {
+	margin-bottom: 5em;
+}
+
 /*
 * Error decoder.
 */

public/css/docs/typography.css

@@ -184,14 +184,12 @@ a:active {
 */
 
 .readme kbd {
-	font-size: 0.6875em;
+	font-size: 1em;
 	font-family: var(--code-font-family);
 
 	color: #555555; /* charcoal */
 
 	line-height: 1em;
-
-	vertical-align: middle;
 }
 
 /*
@@ -338,6 +336,14 @@ a:active {
 	color: var(--feedback-error-text-color);
 }
 
+/*
+* Help page.
+*/
+
+.help h1 button.icon-button .icon {
+	fill: var(--theme-text-color);
+}
+
 /*
 * Search results.
 */

src/app.jsx

@@ -47,7 +47,7 @@ import routes from './routes.js';
 // VARIABLES //
 
 var RE_INTERNAL_URL = new RegExp( '^'+config.mount );
-var RE_SEARCH_URL = /\/search\/?/;
+var RE_SEARCH_OR_HELP_URL = /(\/search|\/help)\/?/;
 var RE_FORWARD_SLASH = /\//g;
 var RE_PLOT_PKG = /\/plot/;
 
@@ -161,14 +161,11 @@ class App extends React.Component {
 			// Boolean indicating whether to show the side menu:
 			'sideMenu': false,
 
-			// Boolean indicating whether keyboard shortcuts are active:
-			'shortcuts': true,
-
 			// Boolean indicating whether a notification is currently displayed:
 			'notification': props.location.search.indexOf( 'notification' ) >= 0
 		};
 
-		// Previous (non-search) location (e.g., used for navigating to previous page after closing search results):
+		// Previous (non-search/help) location (e.g., used for navigating to previous page after closing search results):
 		this._prevLocation = config.mount; // default is API docs landing page
 
 		// Create a `ref` to point to a DOM element for resetting focus on page change:
@@ -278,9 +275,9 @@ class App extends React.Component {
 		if ( this.state.query === '' ) {
 			return;
 		}
-		// If we are coming from a non-search page, cache the current location...
+		// If we are coming from a non-search/help page, cache the current location...
 		path = this.props.location.pathname;
-		if ( RE_SEARCH_URL.test( path ) === false ) {
+		if ( RE_SEARCH_OR_HELP_URL.test( path ) === false ) {
 			this._prevLocation = path;
 		}
 		// Resolve a search URL based on the search query:
@@ -291,65 +288,30 @@ class App extends React.Component {
 	}
 
 	/**
-	* Callback invoked upon closing search results.
-	*
-	* @private
-	*/
-	_onSearchClose = () => {
-		// Manually update the history to trigger navigation to a previous (non-search) page:
-		this.props.history.push( this._prevLocation );
-
-		// Update the component state:
-		this.setState({
-			'query': '' // reset the search input element
-		});
-	}
-
-	/**
-	* Callback invoked when the search input element receives focus.
+	* Callback invoked upon submitting a search query.
 	*
 	* @private
+	* @returns {void}
 	*/
-	_onSearchFocus = () => {
-		// Whenever the search input element receives focus, we want to disable keyboard shortcuts:
-		this.setState({
-			'shortcuts': false
-		});
-	}
+	_onHelpOpen = () => {
+		var path = config.mount + this.props.version + '/help';
 
-	/**
-	* Callback invoked when the search input element loses focus.
-	*
-	* @private
-	*/
-	_onSearchBlur = () => {
-		// Whenever the search input element loses focus, we can enable keyboard shortcuts:
-		this.setState({
-			'shortcuts': true
-		});
+		// Manually update the history to trigger navigation to the help page:
+		this.props.history.push( path );
 	}
 
 	/**
-	* Callback invoked when the side menu filter receives focus.
+	* Callback invoked upon closing search results.
 	*
 	* @private
 	*/
-	_onFilterFocus = () => {
-		// Whenever the side menu filter receives focus, we want to disable keyboard shortcuts:
-		this.setState({
-			'shortcuts': false
-		});
-	}
+	_onSearchClose = () => {
+		// Manually update the history to trigger navigation to a previous (non-search/help) page:
+		this.props.history.push( this._prevLocation );
 
-	/**
-	* Callback invoked when the side menu filter loses focus.
-	*
-	* @private
-	*/
-	_onFilterBlur = () => {
-		// Whenever the side menu filter loses focus, we can enable keyboard shortcuts:
+		// Update the component state:
 		this.setState({
-			'shortcuts': true
+			'query': '' // reset the search input element
 		});
 	}
 
@@ -464,22 +426,24 @@ class App extends React.Component {
 
 				onSearchChange={ this._onSearchChange }
 				onSearchSubmit={ this._onSearchSubmit }
-				onSearchFocus={ this._onSearchFocus }
-				onSearchBlur={ this._onSearchBlur }
+				onSearchFocus={ this.props.onSearchFocus }
+				onSearchBlur={ this.props.onSearchBlur }
 
-				onFilterFocus={ this._onFilterFocus }
-				onFilterBlur={ this._onFilterBlur }
+				onFilterFocus={ this.props.onFilterFocus }
+				onFilterBlur={ this.props.onFilterBlur }
 
 				onVersionChange={ this.props.onVersionChange }
 
+				onHelpOpen={ this._onHelpOpen }
+
 				onAllowSettingsCookiesChange={ this.props.onAllowSettingsCookiesChange }
 				onThemeChange={ this.props.onThemeChange }
 				onModeChange={ this.props.onModeChange }
 				onExampleSyntaxChange={ this.props.onExampleSyntaxChange }
 				onPrevNextNavChange={ this.props.onPrevNextNavChange }
 
 				sideMenu={ this.state.sideMenu }
-
+				shortcuts = { this.props.shortcuts }
 				allowSettingsCookies={ this.props.allowSettingsCookies }
 				theme={ this.props.theme }
 				mode={ this.props.mode }
@@ -565,6 +529,7 @@ class App extends React.Component {
 					prev={ prev }
 					next={ next }
 					url={ match.url }
+					shortcuts={ this.props.shortcuts }
 					content={ this.props.content }
 					onClick={ this._onReadmeClick }
 				/>
@@ -748,6 +713,7 @@ class App extends React.Component {
 					version={ match.params.version }
 					query={ query }
 					onClose={ this._onSearchClose }
+					shortcuts={ this.props.shortcuts }
 				/>
 			</Fragment>
 		);
@@ -771,6 +737,7 @@ class App extends React.Component {
 				/>
 				<Help
 					onClose={ this._onHelpClose }
+					shortcuts={ this.props.shortcuts }
 				/>
 			</Fragment>
 		);

src/client.jsx

@@ -40,6 +40,12 @@ var COOKIES = [
 	'prevnextnavigation'
 ];
 
+var THEMES = [
+	'light',
+	'dark'
+	// more to come... hopefully...
+]
+
 // MAIN //
 
 /**
@@ -131,7 +137,10 @@ class ClientApp extends React.Component {
 			'exampleSyntax': cookies.examplesyntax || config.exampleSyntax,
 
 			// Previous/next package navigation:
-			'prevNextNavigation': cookies.prevnextnavigation || config.prevNextNavigation
+			'prevNextNavigation': cookies.prevnextnavigation || config.prevNextNavigation,
+
+			// Boolean indicating whether keyboard shortcuts are active:
+			'shortcuts': true
 		};
 	}
 
@@ -269,6 +278,75 @@ class ClientApp extends React.Component {
 		});
 	}
 
+    /**
+	* Callback invoked when the search input element receives focus.
+	*
+	* @private
+	*/
+	_onSearchFocus = () => {
+		// Whenever the search input element receives focus, we want to disable keyboard shortcuts:
+		this.setState({
+			'shortcuts': false
+		});
+	}
+
+	/**
+	* Callback invoked when the search input element loses focus.
+	*
+	* @private
+	*/
+	_onSearchBlur = () => {
+		// Whenever the search input element loses focus, we can enable keyboard shortcuts:
+		this.setState({
+			'shortcuts': true
+		});
+	}
+
+	/**
+	* Callback invoked when the side menu filter receives focus.
+	*
+	* @private
+	*/
+	_onFilterFocus = () => {
+		// Whenever the side menu filter receives focus, we want to disable keyboard shortcuts:
+		this.setState({
+			'shortcuts': false
+		});
+	}
+
+	/**
+	* Callback invoked when the side menu filter loses focus.
+	*
+	* @private
+	*/
+	_onFilterBlur = () => {
+		// Whenever the side menu filter loses focus, we can enable keyboard shortcuts:
+		this.setState({
+			'shortcuts': true
+		});
+	}
+
+	/**
+	* Callback invoked upon a user press down a key to cycle through available themes
+	*
+	* @private
+	* @param {Object} event - event object
+	* @returns {void}
+	*/
+	_changeTheme = ( event ) => {
+		if ( event.shiftKey && event.key === "A" && this.state.shortcuts ) {
+			var changedTheme;
+			var currentThemeIndex = THEMES.indexOf( this.state.theme )
+			if( currentThemeIndex === THEMES.length - 1 ){
+				changedTheme = THEMES[0]  
+			}
+			else{
+				changedTheme = THEMES[currentThemeIndex + 1]
+			}
+			this._onThemeChange( changedTheme );
+		}
+	};
+
 	/**
 	* Callback invoked immediately after mounting a component (i.e., is inserted into a tree).
 	*
@@ -304,6 +382,17 @@ class ClientApp extends React.Component {
 				'data': data
 			});
 		}
+		document.addEventListener( "keyup", this._changeTheme );
+	}
+
+	/**
+	* Callback invoked immediately after unmounting a component (i.e., is removed from a tree).
+	*
+	* @private
+	*/
+	componentWillUnmount() {
+		// Clean up event listener
+		document.removeEventListener( "keyup", this._changeTheme );
 	}
 
 	/**
@@ -337,6 +426,12 @@ class ClientApp extends React.Component {
 						onModeChange={ this._onModeChange }
 						onExampleSyntaxChange={ this._onExampleSyntaxChange }
 						onPrevNextNavChange={ this._onPrevNextNavChange }
+
+						shortcuts={ this.state.shortcuts }
+						onSearchFocus={ this._onSearchFocus }
+						onSearchBlur={ this._onSearchBlur }
+						onFilterFocus={ this._onFilterFocus }
+						onFilterBlur={ this._onFilterBlur }
 					/>
 				</HelmetProvider>
 			</BrowserRouter>