Blockly.JavaScript[''] = function()

in generators/javascript/lists.js [83:160]

• 75 lines of code
• 25 McCabe index (conditional complexity)

Blockly.JavaScript['lists_getIndex'] = function(block) {
  // Get element at index.
  // Note: Until January 2013 this block did not have MODE or WHERE inputs.
  var mode = block.getFieldValue('MODE') || 'GET';
  var where = block.getFieldValue('WHERE') || 'FROM_START';
  var listOrder = (where == 'RANDOM') ? Blockly.JavaScript.ORDER_NONE :
      Blockly.JavaScript.ORDER_MEMBER;
  var list = Blockly.JavaScript.valueToCode(block, 'VALUE', listOrder) || '[]';

  switch (where) {
    case ('FIRST'):
      if (mode == 'GET') {
        var code = list + '[0]';
        return [code, Blockly.JavaScript.ORDER_MEMBER];
      } else if (mode == 'GET_REMOVE') {
        var code = list + '.shift()';
        return [code, Blockly.JavaScript.ORDER_MEMBER];
      } else if (mode == 'REMOVE') {
        return list + '.shift();\n';
      }
      break;
    case ('LAST'):
      if (mode == 'GET') {
        var code = list + '.slice(-1)[0]';
        return [code, Blockly.JavaScript.ORDER_MEMBER];
      } else if (mode == 'GET_REMOVE') {
        var code = list + '.pop()';
        return [code, Blockly.JavaScript.ORDER_MEMBER];
      } else if (mode == 'REMOVE') {
        return list + '.pop();\n';
      }
      break;
    case ('FROM_START'):
      var at = Blockly.JavaScript.getAdjusted(block, 'AT');
      if (mode == 'GET') {
        var code = list + '[' + at + ']';
        return [code, Blockly.JavaScript.ORDER_MEMBER];
      } else if (mode == 'GET_REMOVE') {
        var code = list + '.splice(' + at + ', 1)[0]';
        return [code, Blockly.JavaScript.ORDER_FUNCTION_CALL];
      } else if (mode == 'REMOVE') {
        return list + '.splice(' + at + ', 1);\n';
      }
      break;
    case ('FROM_END'):
      var at = Blockly.JavaScript.getAdjusted(block, 'AT', 1, true);
      if (mode == 'GET') {
        var code = list + '.slice(' + at + ')[0]';
        return [code, Blockly.JavaScript.ORDER_FUNCTION_CALL];
      } else if (mode == 'GET_REMOVE') {
        var code = list + '.splice(' + at + ', 1)[0]';
        return [code, Blockly.JavaScript.ORDER_FUNCTION_CALL];
      } else if (mode == 'REMOVE') {
        return list + '.splice(' + at + ', 1);';
      }
      break;
    case ('RANDOM'):
      var functionName = Blockly.JavaScript.provideFunction_(
          'listsGetRandomItem',
          ['function ' + Blockly.JavaScript.FUNCTION_NAME_PLACEHOLDER_ +
              '(list, remove) {',
           '  var x = Math.floor(Math.random() * list.length);',
           '  if (remove) {',
           '    return list.splice(x, 1)[0];',
           '  } else {',
           '    return list[x];',
           '  }',
           '}']);
      code = functionName + '(' + list + ', ' + (mode != 'GET') + ')';
      if (mode == 'GET' || mode == 'GET_REMOVE') {
        return [code, Blockly.JavaScript.ORDER_FUNCTION_CALL];
      } else if (mode == 'REMOVE') {
        return code + ';\n';
      }
      break;
  }
  throw Error('Unhandled combination (lists_getIndex).');
};