Convert Gulp 3 to Gulp 4 with a codemod

gulp-to-gulp4-codemod.js

// Use https://astexplorer.net/

export default function transformer(file, api) {
  const j = api.jscodeshift;
  const root = j(file.source);
  
  const gulpTaskCalls = root.find(j.CallExpression, {
    callee: {
      object: {
        name: 'gulp'
      },
      property: {
        name: 'task'
      }
    }
  });
  
  gulpTaskCalls.forEach(p => {
    if(p.node.arguments[1].type === 'ArrayExpression') {
	const dependentTasks = p.node.arguments[1].elements;
      
      	const isThirdArgFunction = p.node.arguments[2].type === "FunctionExpression" || p.node.arguments[2].type === "ArrowFunctionExpression"	
       
        if (isThirdArgFunction) {
        	dependentTasks.push(p.node.arguments[2])
          	delete p.node.arguments[2];
        }
        
    	p.node.arguments[1] = j.callExpression(
          j.identifier('gulp.series'),
          dependentTasks
        );
      
      	
    }
  });

  return root.toSource({quote: 'single'});
}