确定是否从另一个任务调用Gulp任务

Question

是否有一种方法可以确定某个任务是直接调用的，还是从另一个任务调用的？

  runSequence = require 'run-sequence'

  gulp.task 'build', ->
     ....

  gulp.task 'run', ->
     runSequence 'build', -> gulp.start('server')

我需要一个if案例在build任务中说:如果它被直接调用- (gulp build)，那么做些什么；

或者，如果它是从run任务调用的，那么执行其他操作

Answer 1

这可能是一个X/Y problem。你到底想做什么？

，但要回答这个问题，；我认为唯一的方法是查看调用堆栈跟踪，并确保只有Gulp才能触及任务。我写了一个函数来找出谁策划了这个任务。您只需将该函数与您的gulpfile.js内联，并像布尔值一样使用它。

下面的代码依赖于npm parse-stack，所以请确保npm install parse-stack

用法：if(wasGulpTaskCalledDirectly()) { /*...*/ }

function wasGulpTaskCalledDirectly()
{
    var parseStack = require("parse-stack");

    var stack = parseStack(new Error());

    // Find the index in the call stack where the task was started
    var stackTaskStartIndex = -1;
    for(var i = 0; i < stack.length; i++)
    {
        if(stack[i].name == 'Gulp.Orchestrator.start')
        {
            stackTaskStartIndex = i;
            break;
        }
    }

    // Once we find where the orchestrator started the task
    // Find who called the orchestrator (one level up)
    var taskStarterIndex = stackTaskStartIndex+1;
    var isValidIndex = taskStarterIndex > 0 && taskStarterIndex < stack.length;
    if(isValidIndex && /gulp\.js$/.test((stack[taskStarterIndex].filepath || "")))
    {
        return true;
    }

    return false;
}

您可以在下面找到用于测试的完整gulpfile.js：

// This is a test for this SE question: http://stackoverflow.com/q/25928170/796832
// Figure out how to detect `gulp` vs `gulp build`

// Include gulp
var gulp = require('gulp');
var runSequence = require('run-sequence');


// Add this in from the above code block in the answer
//function wasGulpTaskCalledDirectly()
	// ...

gulp.task('build', function() {
	//console.log(wasGulpTaskCalledDirectly());
	if(wasGulpTaskCalledDirectly())
	{
		// Do stuff here
	}
	else
	{
		// Do other stuff here
	}

	return gulp.src('./index.html', {base: './'})
		.pipe(gulp.dest('./dist'));
});

// This does nothing
gulp.task('start-server', function() {
	return gulp.src('./index.html', {base: './'});
});


// Default Task
gulp.task('default', function(callback) {
	runSequence('build',
		['start-server'],
		callback
	);
});

​