title: React: validateDOMNesting: #text cannot appear as a child of <tr>
body: <p>Can you explain me why react show warning <code>Warning: validateDOMNesting(...): #text cannot appear as a child of &lt;tr&gt;. See Router &gt; RouterContext &gt; CarWashPage &gt; AllCarWashTable &gt; tr &gt; #text.</code>? I don't see any text inside tag <code>tr</code></p>
  
  <p><strong>Code that renders table</strong></p>
  
  <pre><code>export default class AllCarWashTable extends React.Component{
  
  constructor(props) {
      super(props);
      this.generateHeaders = this.generateHeaders.bind(this);
      this.generateRows = this.generateRows.bind(this);
  };
  
  static propTypes = {
      cols : React.PropTypes.array.isRequired,
      rows : React.PropTypes.array.isRequired
  }
  
  generateHeaders() {
      let cols = this.props.cols;  // [{key, label}]
      return cols.map(function(colData) {
          return &lt;th key={colData.key}&gt; {colData.label} &lt;/th&gt;;
      });
  }
  
  generateRows() {
      let cols = this.props.cols,  // [{key, label}]
          data = this.props.rows;
      if (this.props.rows.length &gt; 0) {
          return data.map(function(item) {
              var cells = cols.map(function(colData) {
                  return &lt;td key={colData.key}&gt; {item[colData.key]} &lt;/td&gt;;
              });
              return &lt;tr key={item.id}&gt; {cells} &lt;/tr&gt;;
          });
      }
  }
  
  render(){
      let headers = this.generateHeaders();
      let rows = this.generateRows();
  
      return (
           &lt;table className="table table-hove"&gt;
               &lt;thead&gt;
                  &lt;tr&gt;
                      {headers}
                  &lt;/tr&gt;
               &lt;/thead&gt;
               &lt;tbody&gt;
                      {rows}
               &lt;/tbody&gt;
  
           &lt;/table&gt;
      )
  }
  }
  </code></pre>
  
  <p>At the end, <strong>my table has the following structure</strong> </p>
  
  <p><a href="https://i.stack.imgur.com/ebTAe.png" rel="noreferrer"><img src="https://i.stack.imgur.com/ebTAe.png" alt="enter image description here"></a></p>
  
  <p>Where is the problem?</p>