text: 
  function addTable(table_id) {
    const body = document.getElementsByTagName('body')[0];
    const element = document.createElement('table');
    element.id = table_id;
    body.appendChild(element);
    return element;
  }
  
  describe("Create a field to play", function() {
  
    it("returns false if there is already one", function() {
      let table_id = "field_exists";
      let table = addTable(table_id);
      const table_cell = document.createElement('th');
      table.appendChild(table_cell);
      expect(createField(table_id)).toBe(false);
    });
  
    it("returns false if there is no place for a field", function(){
      let table_id = "place_exists";
      expect(createField(table_id)).toBe(false);
    });
  
    it("returns true if a playfield was succesfully added", function(){
      let table_id = "playfield";
      let table = addTable(table_id);
      const table_cell = document.createElement('th');
      table.appendChild(table_cell);
      expect(createField(table_id)).toBe(true);
    });
  
  });
  
  describe("Check if a HTML-element is a proper playfield", function(){
  
    let table_id = "proper_field";
    let element = document.getElementById(table_id);
    it("returns true", function(){
      expect(isProperField(element)).toBe(true);
    });
  
  })
  
  describe("Check if there is a field to play", function(){
  
    describe("if there is no one", function(){
      let table_id = "field_not_exist_test";
      addTable(table_id);
      it("returns false", function() {
        expect(isFieldExists(table_id)).toBe(false);
      });
    })
  
    describe("if there is a one", function() {
      let table_id = "field_exist_test";
      let table = addTable(table_id);
      const table_cell = document.createElement('th');
      table.appendChild(table_cell);
      
      it("returns true", function() {
        expect(isFieldExists(table_id)).toBe(true);
      });
    })
    
  });
  
  describe("Check if there is a place for a field", function(){
     
    describe("if there is no one", function(){
      let table_id = "place_not_exist_test";
      it("returns false", function(){
        expect(isFieldPlaceExists(table_id)).toBe(false);
      });
    })
  
    describe("if there is one", function(){
      let table_id = "place_exist_test";
      addTable(table_id);
  
      it("returns true", function(){
        expect(isFieldPlaceExists(table_id)).toBe(true);
      });
    })
  
  });