Method highlightLines

blocks/code/code-editor.js:68–75

( lines, prevLines = [] )

	}

	highlightLines( lines, prevLines = [] ) {
		const doc = this.editor.codemirror;
		const className = 'CodeMirror-linebackground-highlight';
		const arrayDifference = ( array1, array2 ) => array1.filter( value => ! array2.includes( value ) );

		lines.forEach( line => doc.addLineClass( line, 'background', className ) );
		arrayDifference( prevLines, lines ).forEach( line => doc.removeLineClass( line, 'background', className ) );
	}

	updateLanguageSettings( value ) {
		const settings = getLanguageSettings( value );